Abstract
Objectives
The impact of a syringe services program (SSP) policy on risk behaviors and its durability are not as well studied as the impact of the SSPs themselves. We examined whether trends in syringe sharing among persons who inject drugs (PWID) were associated with changes to syringe access policies in 3 US cities: Denver, New Orleans, and Philadelphia.
Methods
PWID were surveyed through National HIV Behavioral Surveillance System surveys in each city in 2005, 2009, 2012, and 2015. We assessed changes in syringe sharing from 2005 to 2015 by city. We used multivariable stepwise logistic regression analysis to measure the associations among syringe sharing and injection works sharing, time, and SSP access.
Results
From 2005 to 2015, syringe sharing decreased significantly from 49.1% to 33.1% in Denver (P < .001), increased significantly from 32.0% to 50.5% in New Orleans (P < .001), and remained unchanged in Philadelphia (30.4% to 31.5%; P = .87). Compared with persons who obtained syringes from any nonsterile source, the adjusted odds of syringe sharing among PWID were significantly lower in each city if syringes were obtained from sterile sources only: Denver adjusted odds ratio (aOR) = 0.23 (95% confidence interval [CI], 0.18-0.30; New Orleans aOR = 0.26 (95% CI, 0.19-0.35), and Philadelphia aOR = 0.43 (95% CI, 0.33-0.57).
Conclusions
The lowest proportion of PWID reporting syringe sharing was in Philadelphia, which has a long-standing legal SSP. Implementation of a legal SSP in Denver in 2012 corresponded to a decrease in sharing, whereas the lack of a legal SSP in New Orleans corresponded to an increase in sharing. Universal long-term access to legal SSPs could further the progress made in HIV prevention among PWID.
Keywords: syringe service program policy, persons who inject drugs, syringe access, syringe sharing, NHBS
At the end of 2015, nearly 1 million persons (n = 973 846) were living with diagnosed HIV infection in the United States, of whom 126 704 (13.0%) were persons who inject drugs (PWID).1 PWID accounted for 2224 (5.7%) new HIV infections in 2016, representing a group at continued risk for HIV infection.1 In addition to the continued spread of HIV infection among PWID, an upward trajectory of drug overdose death rates has developed in the United States; in 30 states, including Colorado, Louisiana, and Pennsylvania, drug overdose death rates increased from 2010 to 2015.2
The effectiveness of syringe services programs (SSPs) in reducing the transmission of HIV and hepatitis C virus (HCV) infections by offering sterile syringes and injection equipment is well documented.3-7 Many SSPs also offer access to health and social services (medical clinics, HIV/HCV testing, drug treatment, legal services) that have been shown to further decrease HIV risk behaviors8,9 and promote entry into drug treatment programs.10,11 In addition, SSPs benefit PWID who do not access services directly by increasing the number of sterile syringes in the local PWID networks.12 Studies have shown decreased odds of receptive syringe sharing (using a syringe after it was used by someone else) among PWID who indirectly receive sterile syringes distributed by SSPs.13,14 Implementation of SSPs also has been shown to be effective in reducing HIV risk behaviors among PWID, even in the current opioid epidemic.15
Despite the known individual and population-level benefits of SSPs, access to SSPs varies widely across the United States. Until 2015, the use of federal funding for SSPs was strictly prohibited. Since 2015, federal funding for SSPs can be used only to support certain components of SSPs, such as personnel, HIV and HCV test kits, educational materials, community outreach, naloxone, and planning and evaluation activities, but not to purchase syringes.16 Restrictive SSP policies, which allow only 1-for-1 exchange of syringes, also have been associated with increased risk of syringe sharing (using the same syringe as someone else)17 and exposure to HIV.18 SSPs operated in 41 states (including the District of Columbia) as of August 1, 2019.19 In 39 of these states, 1 or more laws consistent with or explicitly authorizing the legal operation of SSPs were in effect. Thirty-three states had 1 or more laws that were consistent with legal possession of syringes by SSP clients, although legal possession is often conditioned on SSP participation. Legal barriers have declined in recent years, but legal ambiguity, particularly concerning paraphernalia and syringe possession, remains a concern among many PWID.
Community activism and public health practitioners have driven policy changes to syringe access at the local level.20,21 Research has demonstrated the positive effect of permissive policy changes on SSPs, which had previously operated without local governmental approval. For example, support of SSPs through local policy changes in California was shown to increase access to syringes in high-need areas, increase resources available to programs, and decrease police harassment of clients.22 Conversely, restrictive SSP policies can make SSP implementation, management, and use more difficult for staff members and clients. For example, Indiana SSP legislation passed in May 2015 in response to an HIV outbreak was ambiguous with limited guidance or support about how to meet the requirement for individual counties to declare an epidemic.23,24 The piecemeal change in syringe access policies presents a unique opportunity to measure the effect of such policies on risk behaviors among networks of PWID with varying access to syringes over time. One study found that SSP policies that supported widespread distribution of syringes were more effective in reducing the rates of HIV risk behaviors than SSP policies that restricted syringe distribution.25 Another study found syringe policy change itself to be an effective structural intervention for HIV prevention.26 However, research focused on changes in injection works sharing (ie, used the same cooker, cotton, water, syringe for dividing drugs but not injecting, or other injection works that someone else had already used) and syringe-sharing behaviors in the context of SSP policy change is lacking, and the durability over time of these behavior changes is unknown. We examined how injection works sharing and syringe sharing behaviors compared in 3 cities with varying syringe access policies and how these behaviors changed from 2005 to 2015.
The cities of Denver, New Orleans, and Philadelphia are geographically diverse and feature differing SSP policies and syringe possession laws. SSPs have been operating legally in Philadelphia since 199227 and in Denver since 2012.28 SSPs operated in New Orleans illegally starting in 200629 and became legal in 2017.30 SSP policy change in Denver and additional pharmacy syringe access through a 2009 policy change in Philadelphia represent natural interventions to study. In addition, all 3 cities collected serial cross-sectional surveys among PWID through the National HIV Behavioral Surveillance (NHBS) System, which provided a unique opportunity to analyze injection works sharing and syringe sharing behaviors in the context of differential syringe policies. The purpose of our study was to determine whether trends in injection works sharing and syringe sharing among PWID from 2005 to 2015 were associated with the year of initiation of legal SSPs or with changes to syringe access policies in 3 cities.
Methods
Sampling Design and Recruitment
We collected survey data in 2005, 2009, 2012, and 2015 as part of the NHBS System among PWID in Denver, New Orleans, and Philadelphia. NHBS is an in-person, cross-sectional behavioral health survey of populations at high risk for HIV that uses respondent-driven sampling (RDS) methods for data collection among PWID.31 NHBS and RDS methods are described elsewhere.32,33 The NHBS was approved by the Colorado Multiple Institutional Review Board (IRB), Louisiana Department of Health IRB, Louisiana State University Health Sciences Center in New Orleans IRB, and the Philadelphia Department of Public Health IRB.
Measures
We obtained data on new HIV diagnoses for each year of the NHBS from local health departments. We obtained overdose death data from the National Center for Health Statistics,34 and we obtained data on legal syringe distribution from SSPs in Denver (unpublished data, Harm Reduction Action Center, 2012-2015) and Philadelphia (unpublished data, Prevention Point Philadelphia, 2005-2015). Our main outcomes of interest were syringe sharing and injection works sharing in the past year. We chose to analyze both outcomes because differences in the availability of SSPs and laws on pharmacies distributing syringes without a prescription in the 3 cities may have a measurable effect on sharing injection works. We defined syringe sharing as 1 or more instances in the past year in which the participant used the same syringe that someone else had previously used to inject drugs. We defined injection works sharing as 1 or more instances in the past year in which the participant used the same cooker, cotton, water, syringe for dividing drugs but not injecting, or other injection works that someone else had already used.
The main predictors of interest were year of study and syringe source, categorized into sterile source only (obtaining syringes from only an SSP, pharmacy, physician, hospital, or some combination of these sources) or nonsterile source (at least 1 instance in the past year in which the participant obtained syringes from a dealer, friend, or some other source not included in the sterile sources). HIV risk behaviors and medical history questions with yes/no responses included noninjection drug use in the past year, binge drinking in the past 30 days, current health insurance, having had a medical visit in the past year, and drug treatment in the past year. Other covariates included in the analysis were primary injection drug (heroin, cocaine, speedball, methamphetamine, or other/unknown), poverty status (≥federal poverty level or <federal poverty level for each survey year), and homelessness (stably housed or homeless, defined as living in the streets, a shelter, a single-room occupancy hotel, or a car at any point in the past 12 months). Additional demographic variables included race/ethnicity (non-Hispanic white, non-Hispanic black, Hispanic, other), age (18-24, 25-34, 35-44, 45-54, ≥55), sex at birth (male, female), and education (<high school or ≥high school/general educational diploma).
Statistical Methods
We present here unweighted, serial cross-sectional data. Similar analyses have been conducted using serial cross-sectional survey data to identify trends, assuming time alone was sufficient to overcome correlation between observations35 and could represent actual changes in the population between measurement points.36 We analyzed data from all 3 cities separately and performed Pearson χ2 tests for homogeneity on demographic variables to determine significant differences across populations, with P < .05 considered significant.
We used Cochran-Armitage tests for trend to analyze trends across multiple years. Cochran-Armitage is a modified version of the Pearson χ2 test used in categorical data analysis to assess for an association between 2 variables with an ordering of effects in the second variable, time.37 We used bivariable and stepwise multivariable logistic regression models to determine associations between injection works sharing and syringe sharing with sociodemographic characteristics and other HIV risk behaviors. We included variables in multivariable models if their significance level was ≤.05, and they remained in the model if their significance level remained ≤.05.
Results
From 2005 to 2015, the number of new HIV diagnoses among PWID decreased in all 3 cities (Denver: 46 to 22; New Orleans: 221 to 116; Philadelphia: 328 to 35); the number of overdose deaths increased in New Orleans (28 to 102) and Philadelphia (391 to 568) and decreased in Denver (140 to 117) (Table 1). Legal syringe distribution increased from 1 253 417 in 2005 to 2 046 191 in 2015 in Philadelphia and from 116 671 in 2012 (when syringes were first legally distributed) to 599 318 in 2015 in Denver.
Table 1.
Number of new HIV diagnoses,a overdose deaths,b and syringes distributed among persons who inject drugs by legal SSPsc in Denver, New Orleans, and Philadelphia, 2005-2015
| Year | Denver | New Orleans | Philadelphia | ||||||
|---|---|---|---|---|---|---|---|---|---|
| No. of New HIV Diagnoses | No. of Overdose Deaths | No. of Syringes Distributed | No. of New HIV Diagnoses | No. of Overdose Deaths | No. of Syringes Distributed | No. of New HIV Diagnoses | No. of Overdose Deaths | No. of Syringes Distributed | |
| 2005 | 46 | 140 | NAd | 221 | 28 | NAd | 328 | 391 | 1 253 417 |
| 2009 | 25 | 169 | NAd | 224 | 49 | NAd | 129 | 351 | 1 489 288 |
| 2012 | 20 | 126 | 116 671 | 135 | 72 | NAd | 94 | 457 | 1 701 379 |
| 2015 | 22 | 117 | 599 318 | 116 | 102 | NAd | 35 | 568 | 2 046 191 |
Abbreviations: NA, not available; SSP, syringe services program.
aData sources: unpublished data, email communication with Colorado Department of Public Health and Environment (Denver), 2005-2015; unpublished data, email communication with Louisiana Office of Public Health (New Orleans), 2005-2015; and unpublished data, communication with Philadelphia Department of Public Health (Philadelphia), 2005-2015.
bOverdose deaths were based on the International Classification of Diseases, 10th Revision code.38 Multiple-cause-of-death data are from 1999-2017. Data source: CDC WONDER.34
cNumber of syringes distributed legally by local SSPs. Unpublished data sources: Prevention Point Philadelphia (Philadelphia) 2005-2015, Harm Reduction Action Center (Denver) 2012-2015.
dIndicates years for which syringes were not legally distributed.
The 6303 PWID (2064 in Denver, 1979 in New Orleans, and 2260 in Philadelphia) interviewed from 2005 to 2015 differed substantially across cities by demographic characteristics (Table 2). Compared with PWID who obtained syringes from nonsterile sources, PWID who obtained syringes from only sterile sources had significantly lower adjusted odds of syringe sharing (77% less in Denver, 74% less in New Orleans, and 57% less in Philadelphia) and significantly lower adjusted odds of injection works sharing, even after controlling for year (73% less in Denver, 69% less in New Orleans, and 48% less in Philadelphia) (Table 3).
Table 2.
Demographic and drug injection characteristics among samples of persons who inject drugs in Denver, New Orleans, and Philadelphia (n = 6303), 2005-2015a
| Characteristic | Denver (n = 2064) | New Orleans (n = 1979) | Philadelphia (n = 2260) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2005 | 2009 | 2012 | 2015 | 2005 | 2009 | 2012 | 2015 | 2005 | 2009 | 2012 | 2015 | |
| No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | |
| Total | 519 | 428 | 516 | 601 | 231 | 621 | 507 | 620 | 504 | 535 | 564 | 657 |
| Race/ethnicityb | ||||||||||||
| Non-Hispanic white | 251 (48.4) | 220 (51.4) | 265 (51.4) | 350 (58.2) | 45 (19.5) | 233 (37.5) | 185 (36.5) | 309 (49.8) | 170 (33.7) | 194 (36.3) | 274 (48.6) | 433 (65.9) |
| Non-Hispanic black | 77 (14.8) | 56 (13.1) | 62 (12.0) | 47 (7.8) | 96 (41.6) | 346 (55.7) | 276 (54.4) | 259 (41.8) | 285 (56.5) | 249 (46.5) | 193 (34.2) | 72 (11.0) |
| Hispanic | 145 (27.9) | 113 (26.4) | 150 (29.1) | 152 (25.3) | 7 (3.0) | 14 (2.3) | 20 (3.9) | 23 (3.7) | 38 (7.5) | 81 (15.1) | 90 (16.0) | 129 (19.6) |
| Other/unknown | 46 (8.9) | 39 (9.1) | 39 (7.6) | 52 (8.7) | 83 (35.9) | 28 (4.5) | 26 (5.1) | 29 (4.7) | 11 (2.2) | 11 (2.1) | 7 (1.2) | 23 (3.5) |
| Age, yb | ||||||||||||
| 18-24 | 34 (6.6) | 28 (6.5) | 40 (7.8) | 58 (9.7) | 22 (9.5) | 13 (2.1) | 25 (4.9) | 39 (6.3) | 23 (4.6) | 13 (2.4) | 23 (4.1) | 54 (8.2) |
| 25-34 | 87 (16.8) | 83 (19.4) | 96 (18.6) | 164 (27.3) | 28 (12.1) | 92 (14.8) | 103 (20.3) | 169 (27.3) | 81 (16.1) | 95 (17.8) | 160 (28.4) | 259 (39.4) |
| 35-44 | 145 (27.9) | 105 (24.5) | 147 (28.5) | 141 (23.5) | 56 (24.2) | 139 (22.4) | 104 (20.5) | 197 (31.8) | 164 (32.5) | 143 (26.7) | 149 (26.4) | 185 (28.2) |
| 45-54 | 200 (38.5) | 119 (27.8) | 134 (26.0) | 148 (24.6) | 98 (42.4) | 273 (44.0) | 187 (36.9) | 141 (22.7) | 194 (38.5) | 144 (26.9) | 122 (21.6) | 111 (16.9) |
| ≥55 | 53 (10.2) | 93 (21.7) | 99 (19.2) | 90 (15.0) | 27 (11.7) | 104 (16.7) | 88 (17.4) | 74 (11.9) | 42 (8.3) | 140 (26.2) | 110 (19.5) | 48 (7.3) |
| Sexb | ||||||||||||
| Male | 371 (71.5) | 295 (68.9) | 393 (76.2) | 427 (71.0) | 193 (83.5) | 508 (81.8) | 410 (80.9) | 473 (76.3) | 346 (68.7) | 402 (75.1) | 407 (72.2) | 493 (75.0) |
| Female | 148 (28.5) | 133 (31.1) | 123 (23.8) | 174 (29.0) | 38 (16.5) | 113 (18.2) | 97 (19.1) | 147 (23.7) | 158 (31.3) | 133 (24.9) | 157 (27.8) | 164 (25.0) |
| Education | ||||||||||||
| <High school | 171 (32.9) | 117 (27.3) | 125 (24.2) | 140 (23.3) | 59 (25.5) | 239 (38.5) | 189 (37.3) | 231 (37.3) | 204 (40.5) | 176 (32.9) | 183 (32.4) | 194 (29.5) |
| ≥High school | 348 (67.1) | 311 (72.7) | 391 (75.8) | 461 (76.7) | 170 (73.6) | 381 (61.4) | 316 (62.3) | 389 (62.7) | 300 (59.5) | 359 (67.1) | 381 (67.6) | 463 (70.5) |
| ≤FPL | 392 (75.5) | 257 (60.0) | 289 (56.0) | 303 (50.4) | 100 (43.3) | 471 (75.8) | 403 (79.5) | 457 (73.7) | 375 (74.4) | 431 (80.6) | 346 (61.3) | 554 (84.3) |
| Recent homelessnessc | 284 (54.7) | 185 (43.2) | 286 (55.4) | 399 (66.4) | 88 (38.1) | 488 (78.6) | 349 (68.8) | 423 (68.2) | 233 (46.2) | 238 (44.5) | 269 (47.7) | 456 (69.4) |
| Primary injection drugd | ||||||||||||
| Heroin | 251 (48.4) | 310 (72.4) | 322 (62.4) | 351 (58.4) | 76 (32.9) | 357 (57.5) | 301 (59.4) | 422 (68.1) | 437 (86.7) | 460 (86.0) | 395 (70.0) | 559 (85.1) |
| Cocaine | 113 (21.8) | 21 (4.9) | 21 (4.1) | 16 (2.7) | 32 (13.9) | 158 (25.4) | 111 (21.9) | 28 (4.5) | 33 (6.5) | 16 (3.0) | 30 (5.3) | 17 (2.6) |
| Speedball | 103 (19.8) | 35 (8.2) | 55 (10.7) | 32 (5.3) | 7 (3.0) | 48 (7.7) | 47 (9.3) | 109 (17.6) | 31 (6.2) | 56 (10.5) | 137 (24.3) | 79 (12.0) |
| Methamphetamine | 11 (2.1) | 57 (13.3) | 106 (20.5) | 178 (29.6) | 1 (0.4) | 26 (4.2) | 26 (5.1) | 40 (6.5) | 1 (0.2) | 2 (0.4) | 0 | 0 |
| Other/unknown | 41 (7.9) | 5 (1.2) | 12 (2.3) | 24 (4.0) | 115 (49.8) | 32 (5.2) | 22 (4.3) | 21 (3.4) | 2 (0.4) | 1 (0.2) | 2 (0.4) | 2 (0.3) |
| Syringe sourcee | ||||||||||||
| Sterile only | 159 (30.6) | 155 (36.2) | 139 (26.9) | 129 (21.5) | 126 (54.5) | 100 (16.1) | 71 (14.0) | 86 (13.9) | 147 (29.2) | 111 (20.7) | 96 (17.0) | 133 (20.2) |
| Some nonsterile | 360 (69.4) | 273 (63.8) | 377 (73.1) | 472 (78.5) | 105 (45.5) | 521 (83.9) | 436 (86.0) | 534 (86.1) | 357 (70.8) | 424 (79.3) | 467 (82.8) | 524 (79.8) |
| Noninjection drug usef | 430 (82.9) | 395 (92.3) | 409 (79.3) | 509 (84.7) | 191 (82.7) | 535 (86.2) | 423 (83.4) | 484 (78.1) | 378 (75.0) | 346 (64.7) | 386 (68.4) | 497 (75.6) |
| Binge drinkingg | 374 (72.1) | 313 (73.1) | 395 (76.6) | 413 (68.7) | 117 (50.6) | 372 (59.9) | 339 (66.9) | 222 (35.8) | 252 (50.0) | 158 (29.5) | 125 (22.2) | 148 (22.5) |
| Current health careh | 193 (37.2) | 196 (45.8) | 277 (53.7) | 532 (88.5) | 12 (5.2) | 172 (27.7) | 227 (44.8) | 263 (42.4) | 292 (57.9) | 402 (75.1) | 399 (70.7) | 505 (76.9) |
| Recent medical visiti | 384 (74.0) | 322 (75.2) | 409 (79.3) | 487 (81.0) | 153 (66.2) | 442 (71.2) | 384 (75.7) | 488 (78.7) | 386 (76.6) | 402 (75.1) | 447 (79.3) | 477 (72.6) |
| Recent drug treatmentj | 192 (37.0) | 176 (41.1) | 184 (35.7) | 244 (40.6) | 55 (23.8) | 194 (31.2) | 119 (23.5) | 219 (35.3) | 152 (30.2) | 203 (37.9) | 265 (47.0) | 327 (49.8) |
| Share worksk | 343 (66.1) | 239 (55.8) | 272 (52.7) | 343 (57.1) | 118 (51.1) | 382 (61.5) | 316 (62.3) | 459 (74.0) | 314 (62.3) | 317 (59.3) | 334 (59.2) | 427 (65.0) |
| Share syringel | 255 (49.1) | 172 (40.2) | 168 (32.6) | 199 (33.1) | 74 (32.0) | 247 (39.8) | 209 (41.2) | 313 (50.5) | 153 (30.4) | 151 (28.2) | 137 (24.3) | 207 (31.5) |
| Share anythingm | 373 (71.9) | 261 (61.0) | 288 (55.8) | 366 (60.9) | 129 (55.8) | 390 (62.8) | 330 (65.1) | 469 (75.6) | 319 (63.3) | 321 (60.0) | 340 (60.3) | 439 (66.8) |
Abbreviations: FPL, federal poverty level; SSP, syringe services program.
aData sources: unpublished data, email communication with Colorado Department of Public Health and Environment (Denver), 2005-2015; unpublished data, email communication with Louisiana Office of Public Health (New Orleans), 2005-2015; and unpublished data, communication with Philadelphia Department of Public Health (Philadelphia), 2005-2015.
bSignificant at P < .05 using the Pearson χ2 test for homogeneity across populations.
cReport of homelessness in the 12 months before the survey.
dDrug that the participant reported injecting the most often in the 12 months before the survey.
eDefined as obtaining syringes only from an SSP, pharmacy, physician, hospital, or some combination of these sources in the past year. Obtaining syringes from a nonsterile source was defined as at least 1 instance in the past year in which the participant obtained syringes from such sources as a dealer, friend, or some other source.
fReport of 1 or more instances in the past year in which the participant used noninjected illicit drugs.
gReport of binge drinking in the past 30 days.
hReport of having current health insurance or health care coverage.
iReport of visiting a physician, nurse, or other health care provider in the 12 months before the survey.
jReport of participating in a drug treatment program in the 12 months before the survey.
kOne or more instances in the past year in which the participant used the same cooker, cotton, water, syringe for dividing drugs but not injecting, or other injection works that someone else had already used.
lOne or more instances in the past year in which the participant used the same syringe that someone else had previously used to inject drugs.
mOne or more instances in the past year in which the participant used the same syringe or injection works that someone else had already used.
Table 3.
Unadjusted and adjusted odds of syringe sharing and injection works sharinga among samples of persons who inject drugs, by year and syringe source, Denver, New Orleans, and Philadelphia, 2005-2015b
| Year and Syringe Sourcec | Denverd | New Orleansf | Philadelphiag | |||
|---|---|---|---|---|---|---|
| OR (95% CI) [P Value]e | aOR (95% CI) [P Value]e | OR (95% CI) [P Value]e | aOR (95% CI)[P Value]e | OR (95% CI) [P Value]e | aOR (95% CI) [P Value]e | |
| Year | Syringe Sharing | |||||
| 2005 | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] |
| 2009 | 0.70 (0.54-0.90) [.01] | —h | 1.40 (1.02-1.93) [.04] | —h | 0.90 (0.69-1.18) [.45] | —h |
| 2012 | 0.50 (0.39-0.64) [<.001] | 0.56 (0.43-0.72) [<.001] | 1.49 (1.07-2.07) [.02] | —h | 0.74 (0.56-0.97) [.03] | 0.60 (0.44-0.81) [.001] |
| 2015 | 0.51 (0.40-0.65) [<.001] | 0.52 (0.40-0.67) [<.001] | 2.16 (1.57-2.97)[<.001] | 1.99 (1.28-3.09)[.002] | 1.06 (0.82-1.36) [.68] | 0.65 (0.48-0.87) [.004] |
| Syringe source | ||||||
| Some not sterile | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] |
| Sterile only | 0.26 (0.20-0.32) [<.001] | 0.23 (0.18-0.30) [<.001] | 0.31 (0.24-0.40)[<.001] | 0.26 (0.19-0.35) [<.001] | 0.36 (0.28-0.47) [<.001] | 0.43 (0.33-0.57) [<.001] |
| Injection Works Sharing | ||||||
| Year | ||||||
| 2005 | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] |
| 2009 | 0.65 (0.50-0.84) [.001] | —h | 1.53 (1.13-2.08) [.01] | —h | 0.88 (0.69-1.13) [.32] | —h |
| 2012 | 0.57 (0.45-0.74) [<.001] | 0.78 (0.62-0.98) [.03] | 1.58 (1.16-2.17) [.004] | —h | 0.88 (0.69-1.12) [.30] | —h |
| 2015 | 0.68 (0.53-0.87) [.002] | —h | 2.73 (1.99-3.74) [<.001] | 1.88 (1.21-2.91) [.01] | 1.12 (0.88-1.43) [.34] | —h |
| Syringe source | ||||||
| Some not sterile | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] | 1.00 [Reference] |
| Sterile only | 0.31 (0.25-0.38) [<.001] | 0.27 (0.22-0.34) [<.001] | 0.29 (0.23-0.37) [<.001] | 0.31 (0.24-0.41) [<.001] | 0.41 (0.34-0.51) [<.001] | 0.52 (0.42-0.64) [<.001] |
Abbreviations: —, nonsignificant aORs; aOR, adjusted odds ratio; OR, unadjusted odds ratio; SSP, syringe services program.
aSyringe sharing refers to 1 or more instances in the past year in which the participant used the same syringe that someone else had previously used to inject drugs. Injection works sharing refers to 1 or more instances in the past year in which the participant used the same cooker, cotton, water, syringe for dividing drugs but not injecting, or other injection works that someone else had already used.
bData sources: unpublished data, email communication with Colorado Department of Public Health and Environment (Denver), 2005-2015; unpublished data, email communication with Louisiana Office of Public Health (New Orleans), 2005-2015; and unpublished data, communication with Philadelphia Department of Public Health (Philadelphia), 2005-2015.
cA sterile source was defined as obtaining syringes from only an SSP, pharmacy, physician, hospital, or some combination of these sources in the past year. Obtaining syringes from a nonsterile source was defined as at least 1 instance in the past year in which the participant obtained syringes from such sources as a dealer, friend, or some other source.
dSSPs became legal in Denver in 2012. Denver syringe-sharing multivariable models adjusted for year, age, homelessness, primary injection drug, and syringe source. Denver works sharing multivariable models adjusted for year, poverty, primary injection drug, syringe source, and drug treatment.
eThe likelihood ratio test of significance was used, with P < .05 considered significant.
fSSPs were not legal in New Orleans for the duration of follow-up. New Orleans syringe-sharing multivariable models adjusted for year, race/ethnicity, age, sex, primary injection drug, non-injection drug use, and syringe source. New Orleans works-sharing multivariable models adjusted for year, age, poverty, primary injection drug, syringe source, binge drinking, and drug treatment.
gSSPs were legal in Philadelphia for the duration of follow-up. Pharmacy sales of syringes became legal in 2009. Philadelphia syringe-sharing multivariable models adjusted for year, race/ethnicity, age, education, homelessness, syringe source, binge drinking, and medical visit. Philadelphia works-sharing multivariable models adjusted for year, race/ethnicity, age, education, homelessness, primary injection drug, syringe source, and binge drinking.
haORs were displayed only if they were significant. Individual years needed to maintain a significance level of <.05 to remain in the final adjusted model.
Denver
Denver PWID reporting methamphetamine as their primary injection drug increased from 2.1% in 2005 to 29.6% in 2015 (Table 2). Syringe sharing decreased significantly overall, from 49.1% to 33.1% (P < .001), and among persons who were non-Hispanic white (53.4% to 34.3%; P < .001), Hispanic (44.8% to 31.6%; P = .01), aged 35-44 (49.7% to 31.9%; P < .001), aged 45-54 (46.0% to 19.6%; P < .001), aged ≥55 (43.4% to 22.2%; P = .01), male (47.7% to 32.6%; P < .001), and female (52.7% to 34.5%; P < .001) from 2005 to 2015 (Table 4). Injection works sharing declined significantly overall (66.1% to 57.1%; P = .002), with significant downward trends observed among persons who were non-Hispanic white (68.5% to 55.4%; P < .001), aged 45-54 (69.5% to 44.6%; P < .001), and male (65.6% to 55.5%; P = .004) from 2005 to 2015 (Table 5).
Table 4.
Syringe sharinga among samples of persons who inject drugs, by demographic characteristics, Denver, New Orleans, and Philadelphia, 2005-2015b
| Characteristic | Denver | New Orleans | Philadelphia | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2005 | 2009 | 2012 | 2015 | 2005 | 2009 | 2012 | 2015 | 2005 | 2009 | 2012 | 2015 | |
| No. (%)c | No. (%) | No. (%) | No. (%) [P Value]c | No. (%) | No. (%) | No. (%) | No. (%) [P Value]c | No. (%) | No. (%) | No. (%) | No. (%) [P Value]c | |
| Overall | 255/519 (49.1) | 172/428 (40.2) | 168/516 (32.6) | 199/601 (33.1) [<.001] | 74/231 (32.0) | 247/621 (39.8) | 209/507 (41.2) | 313/620 (50.5) [<.001] | 153/504 (30.4) | 151/535 (28.2) | 137/564 (24.3) | 207/657 (31.5) [.87] |
| Race/ethnicity | ||||||||||||
| Non-Hispanic white | 134/251 (53.4) | 97/220 (44.1) | 99/265 (37.4) | 120/350 (34.3) [<.001] | 22/45 (48.9) | 98/233 (42.1) | 98/185 (53.0) | 174/309 (56.3) [.004] | 78/170 (45.9) | 81/194 (41.8) | 90/274 (32.8) | 156/433 (36.0) [.01] |
| Non-Hispanic black | 35/77 (45.5) | 19/56 (33.9) | 17/62 (27.4) | 17/47 (36.2) [.13] | 26/96 (27.1) | 135/346 (39.0) | 89/276 (32.2) | 109/259 (42.1) [.09] | 61/285 (21.4) | 36/249 (14.5) | 27/193 (14.0) | 10/72 (13.9) [.03] |
| Hispanic | 65/145 (44.8) | 41/113 (36.3) | 42/150 (28.0) | 48/152 (31.6) [.01] | 2/7 (28.6) | 3/14(21.4) | 7/20(35.0) | 12/23 (52.2) [.08] | 12/38 (31.6) | 30/81 (37.0) | 17/90 (18.9) | 35/129 (27.1) [.19] |
| Other | 21/46 (45.7) | 15/39 (38.5) | 10/39 (25.6) | 14/52 (26.9) [.03] | 24/83 (28.9) | 11/28 (39.3) | 15/26 (57.7) | 18/29 (62.1) [<.001] | 2/11(18.2) | 4/11(36.4) | 3/7(42.9) | 6/23 (26.1) [.82] |
| Age, y | ||||||||||||
| 18-24 | 22/34 (64.7) | 15/28 (53.6) | 13/40 (32.5) | 31/58 (53.4) [.23] | 8/22 (36.4) | 7/13(53.9) | 13/25 (52.0) | 24/39 (61.5) [.07] | 8/23(34.8) | 5/13(38.5) | 11/23 (47.8) | 30/54(55.6) [.07] |
| 25-34 | 46/87 (52.9) | 35/83 (42.2) | 46/96 (47.9) | 74/164 (45.1) [.43] | 10/28 (35.7) | 44/92 (47.8) | 51/103 (49.5) | 103/169 (60.9) [.004] | 31/81 (38.3) | 38/95 (40.0) | 50/160 (31.3) | 87/259(33.6) [.27] |
| 35-44 | 72/145 (49.7) | 46/105 (43.8) | 44/147 (29.9) | 45/141 (31.9) [<.001] | 14/56 (25.0) | 64/139 (46.0) | 39/104 (37.5) | 99/197 (50.3) [.01] | 39/164 (23.8) | 49/143 (34.3) | 35/149 (23.5) | 56/185(30.3) [.50] |
| 45-54 | 92/200 (46.0) | 46/119 (38.7) | 39/134 (29.1) | 29/148 (19.6) [<.001] | 36/98 (36.7) | 103/273 (37.7) | 76/187 (40.6) | 60/141 (42.6) [.26] | 65/194 (33.5) | 38/144 (26.4) | 27/122 (22.1) | 28/111(25.2) [.05] |
| ≥55 | 23/53 (43.4) | 30/93 (32.3) | 26/99 (26.3) | 20/90 (22.2) [.01] | 6/27 (22.2) | 29/104 (27.9) | 30/88 (34.1) | 27/74 (36.5) [.10] | 10/42 (23.8) | 21/140 (15.0) | 14/110 (12.7) | 6/48 (12.5) [.14] |
| Sex | ||||||||||||
| Male | 177/371 (47.7) | 120/295 (40.7) | 132/393 (33.6) | 139/427 (32.6) [<.001] | 62/193 (32.1) | 193/508 (38.0) | 162/410 (39.5) | 222/473 (46.9) [<.001] | 113/346 (32.7) | 103/402 (25.6) | 86/407 (21.1) | 150/493(30.4) [.48] |
| Female | 78/148 (52.7) | 52/133 (39.1) | 36/123 (29.3) | 60/174 (34.5) [<.001] | 12/38 (31.6) | 54/113 (47.8) | 47/97 (48.5) | 91/147 (61.9) [<.001] | 40/158 (25.3) | 48/133 (36.1) | 51/157 (32.5) | 57/164 (34.8) [.12] |
aOne or more instances in the past year in which the participant used the same syringe that someone else had previously used to inject drugs.
bData sources: unpublished data, email communication with Colorado Department of Public Health and Environment (Denver), 2005-2015; unpublished data, email communication with Louisiana Office of Public Health (New Orleans), 2005-2015; and unpublished data, communication with Philadelphia Department of Public Health (Philadelphia), 2005-2015. Within each cell, numerators represent the number of persons who reported sharing syringes for the cell and denominators represent the total number of persons for that cell.
cThe Cochran-Armitage test for trend was used to test significance, with P < .05 considered significant. Cochran-Armitage is a modified version of the Pearson χ2 test used in categorical data analysis to assess for an association between 2 variables with an ordering of effects in the second variable, year.
Table 5.
Injection works sharinga among samples of persons who inject drugs, by demographic characteristics, Denver, New Orleans, and Philadelphia, 2005-2015b
| Characteristic | Denver | New Orleans | Philadelphia | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2005 | 2009 | 2012 | 2015 | 2005 | 2009 | 2012 | 2015 | 2005 | 2009 | 2012 | 2015 | |
| No. (%) | No. (%) | No. (%) | No. (%) [P Value]c | No. (%) | No. (%) | No. (%) | No. (%) [P Value]c | No. (%) | No. (%) | No. (%) | No. (%) [P Value]c | |
| Overall | 343/519 (66.1) | 239/428 (55.8) | 272/516 (52.7) | 343/601 (57.1) [.002] | 118/231 (51.1) | 382/621 (61.5) | 316/507 (62.3) | 459/620 (74.0) [<.001] | 314/504 (62.3) | 317/535 (59.3) | 334/564 (59.2) | 427/657 (65.0) [.29] |
| Race/ethnicity | ||||||||||||
| Non-Hispanic white | 172/251 (68.5) | 130/220 (59.1) | 144/265 (54.3) | 194/350 (55.4) [.001] | 26/45 (57.8) | 143/233 (61.4) | 119/185 (64.3) | 229/309 (74.1) [<.001] | 131/170 (77.1) | 137/194 (70.6) | 179/274 (65.3) | 294/433 (67.9) [.04] |
| Non-Hispanic black | 45/77 (58.4) | 32/56 (57.1) | 35/62 (56.5) | 26/47 (55.3) [.72] | 57/96 (59.4) | 218/346 (63.0) | 167/276 (60.5) | 189/259 (73.0) [.01] | 150/285 (52.6) | 119/249 (47.8) | 94/193 (48.7) | 39/72 (54.2) [.76] |
| Hispanic | 97/145 (66.9) | 62/113 (54.9) | 70/150 (46.7) | 93/152 (61.2) [.16] | 1/7(14.3) | 9/14(64.3) | 12/20 (60.0) | 20/23 (87.0) [<.001] | 26/38 (68.4) | 54/81 (66.7) | 54/90(60.0) | 77/129 (59.7) [.21] |
| Other | 29/46 (63.0) | 15/39 (38.5) | 23/39 (59.0) | 30/52 (57.7) [.94] | 34/83 (41.0) | 12/28 (42.9) | 18/26 (69.2) | 21/29 (72.4) [<.001] | 7/11 (63.6) | 7/11(63.6) | 7/7(100.0) | 17/23 (73.9) [.39] |
| Age, y | ||||||||||||
| 18-24 | 26/34 (76.5) | 21/28 (75.0) | 19/40 (47.5) | 38/58 (65.5) [.14] | 11/22 (50.0) | 10/13 (76.9) | 18/25 (72.0) | 32/39 (82.1) [.01] | 17/23 (73.9) | 12/13 (92.3) | 16/23(69.6) | 41/54 (75.9) [.82] |
| 25-34 | 53/87 (60.9) | 45/83 (54.3) | 57/96 (59.4) | 115/164 (70.1) [.05] | 12/28 (42.9) | 66/92 (71.7) | 74/103 (71.8) | 134/169 (79.3) [<.001] | 56/81 (69.1) | 66/95 (69.5) | 109/160 (68.1) | 176/259 (68.0) [.78] |
| 35-44 | 92/145 (63.4) | 57/105 (54.3) | 81/147 (55.1) | 77/141 (54.6) [.15] | 31/56 (55.4) | 92/139 (66.2) | 65/104 (62.5) | 153/197 (77.7) [<.001] | 97/164 (59.1) | 89/143 (62.2) | 91/149 (61.1) | 124/185 (67.0) [.16] |
| 45-54 | 139/200 (69.5) | 74/119 (62.2) | 64/134 (47.8) | 66/148 (44.6) [<.001] | 54/98 (55.1) | 158/273 (57.9) | 106/187 (56.7) | 98/141 (69.5) [.03] | 122/194 (62.9) | 90/144 (62.5) | 73/122 (59.8) | 65/111 (58.6) [.40] |
| ≥55 | 33/53 (62.3) | 42/93 (45.2) | 51/99 (51.5) | 47/90 (52.2) [.62] | 10/27 (37.0) | 56/104 (53.8) | 53/88 (60.2) | 42/74 (56.8) [.13] | 22/42 (52.4) | 60/140 (42.9) | 45/110 (40.9) | 21/48 (43.8) [.43] |
| Sex | ||||||||||||
| Male | 243/371 (65.5) | 159/295 (53.9) | 202/393 (51.4) | 237/427 (55.5) [.004] | 101/193 (52.3) | 305/508 (60.0) | 246/410 (60.0) | 341/473 (72.1) [<.001] | 220/346 (63.6) | 231/402 (57.5) | 232/407 (57.0) | 330/493 (66.9) [.20] |
| Female | 100/148 (67.6) | 80/133 (60.2) | 70/123 (56.9) | 106/174 (60.9) [.21] | 17/38 (44.7) | 77/113 (68.1) | 70/97 (72.2) | 118/147 (80.3) [<.001] | 94/158 (59.5) | 86/133 (64.7) | 102/157 (65.0) | 97/164 (59.1) [.97] |
aOne or more instances in the past year in which the participant used the same cooker, cotton, water, syringe for dividing drugs but not injecting, or other injection works that someone else had already used.
bData sources: unpublished data, email communication with Colorado Department of Public Health and Environment (Denver), 2005-2015; unpublished data, email communication with Louisiana Office of Public Health (New Orleans), 2005-2015; and unpublished data, communication with Philadelphia Department of Public Health (Philadelphia), 2005-2015. Within each cell, numerators represent the number of persons who reported injection works sharing for the cell and denominators represent the total number of persons for that cell.
cSignificant at P < .05 using the Cochran-Armitage test for trend. Cochran-Armitage is a modified version of the Pearson χ2 test used in categorical data analysis to assess for an association between 2 variables with an ordering of effects in the second variable, year.
Compared with Denver PWID surveyed in 2005, Denver PWID surveyed in 2012 had 44% (95% CI, 0.43-0.72) decreased adjusted odds of syringe sharing (Table 3).
New Orleans
We found significant increases in syringe sharing among PWID in New Orleans overall (32.0% to 50.5%; P < .001) and among PWID who were non-Hispanic white (48.9% to 56.3%; P = .004), aged 25-34 (35.7% to 61.0%; P = .004), aged 35-44 (25.0% to 50.3%; P = .01), male (32.1% to 46.9%; P < .001), and female (31.6% to 61.9%; P < .001) (Table 4). Injection works sharing increased significantly from 51.1% to 74.0% from 2005 to 2015 (Table 5), and injection works sharing increased among all racial/ethnic groups, men and women, and PWID aged <54.
PWID in 2015 had 1.99 (95% CI, 1.28-3.09) higher adjusted odds of syringe sharing and 1.88 (95% CI, 1.21-2.91) higher adjusted odds of injection works sharing than PWID in 2005 (Table 3).
Philadelphia
Syringe sharing decreased significantly among non-Hispanic white (45.9% to 36.0%; P = .01) and non-Hispanic black (21.4% to 13.9%; P = .03) PWID from 2005 to 2015 (Table 4). Injection works sharing decreased significantly among non-Hispanic white PWID (77.1% to 67.9%; P = .04) from 2005 to 2015 (Table 5).
PWID in Philadelphia had 40% (95% CI, 0.44-0.81) lower adjusted odds of syringe sharing in 2012 than in 2005 (Table 3).
Discussion
The number of PWID diagnosed with HIV decreased in all 3 cities from 2005 to 2015 and mirrored the downward trend in HIV diagnoses among PWID nationwide.39 Data demonstrated significant, protective associations between obtaining syringes from sterile sources only and both injection works sharing and syringe sharing in all 3 cities. This finding aligns with previous research on SSPs that found an association between reduced syringe sharing and increased harm-reduction strategies.40
Although PWID populations in Denver, New Orleans, and Philadelphia are geographically, demographically, and politically distinct from one another, data presented here suggest differential local syringe access policies may have a measurable effect on syringe-sharing behaviors. Denver had 1 underground SSP in operation before SSPs were legalized in 2010.41 Denver’s first legal SSP launched in 2012 and distributed more than 116 000 syringes in the first year of operation, which increased to nearly 600 000 syringes by 2015. The SSP also provided services such as HIV testing, substance abuse treatment referrals, and risk-reduction counseling. Although we were unable to determine the number of syringes distributed illegally in New Orleans, an underground SSP that opened in 2006 distributed syringes to approximately 80 PWID clients in 2013.29 The number of syringes distributed by Philadelphia’s SSP increased by roughly 800 000 from 2005 to 2015, even with the addition of legal pharmacy syringe purchases beginning in 2009.
Obtaining syringes from only sterile sources was highly protective in each city, and the survey year had a protective effect in Denver and Philadelphia in 2012 and 2015, corresponding to substantial changes in syringe access legislation. Although the unadjusted OR for syringe sharing by year was significant in Denver in 2009, before the implementation of legal SSPs, it did not remain significant after adjusting for other covariates, suggesting that part of the decreased odds of syringe sharing may be attributed to changes in the underlying PWID population. The reduced odds of syringe sharing in multivariable models in Denver beginning in 2012 corresponded to the year Denver’s SSP began legally distributing syringes.28 Similarly, the reduced odds of syringe sharing in Philadelphia beginning in 2012 corresponded to a September 2009 change in Pennsylvania law that allowed pharmacies to sell syringes without a prescription.42 These reduced odds of syringe sharing persisted and remained significant in 2015 in both cities, suggesting durability of these policies’ protective effects on sharing. The counterintuitive increase in odds of syringe sharing among PWID in New Orleans may be due to increased PWID population size or changes in the PWID population while syringe availability stagnated. This relationship could result in more PWID reusing or sharing a limited number of syringes in distribution, which warrants further study.
The availability of syringes from pharmacies starting in 2009 may partly explain the downward trend in sharing syringes observed among white PWID in Philadelphia, consistent with other studies of the sale of syringes by pharmacies.43-45 In 2012 and 2015, 15.4% and 28.2% of PWID, respectively, reported obtaining syringes from a pharmacy, an increase from 2005 (7.1%) and 2009 (4.5%) (data not shown). In the current study, increases were observed among all racial/ethnic minority groups, and racial/ethnic differences in pharmacy access were exaggerated after the policy change; the proportion of non-Hispanic white PWID in Philadelphia who reported obtaining syringes from pharmacies was twice that of non-Hispanic black PWID. Potential reasons for these differences could be rooted in racial/ethnic bias in nonprescription syringe sales by pharmacists46 and varied access to pharmacies by neighborhood.47 The lack of overall downward trends in risk behaviors in New Orleans and Philadelphia, as well as prevalent risk behaviors among Denver PWID, might be attributed to the proximity to SSPs, legal or otherwise. Several studies found that PWID who lived closer to SSPs were more likely to access these programs and less likely to engage in syringe sharing than PWID who lived farther from SSPs.48-50 Additional factors that may continue to affect syringe-sharing behaviors include varied access to prevention and treatment services, varied mental health needs, and increased fear of criminalization or stigmatization.51
Limitations
This analysis had several limitations. First, although RDS is considered the gold standard of sampling hidden populations,36,52 its validity depends on seeds producing successful referral chains. Because of the interruption of the 2005 survey among PWID in New Orleans by Hurricane Katrina, 2005 data from New Orleans combined data from a 2004 pilot study in New Orleans and the 2005 cycle data. In addition, a burglary during the first NHBS cycle in Philadelphia disrupted referral chains.
Second, although we interpreted differences between cycles as true changes, research suggests that these changes could also be the result of accessing different subpopulations of PWID between cycles, differences in drug-use patterns over time, and variability of RDS measurements.36 Although we were unable to account for differences arising from accessing different subpopulations and variability in RDS measurements, multivariable models were able to partially account for differences in drug-use patterns by controlling for primary injection drug when variability within a city fluctuated over time. The drug markets in the 3 cities in this analysis differed substantially, including the use of black tar heroin in Denver compared with powder heroin in Philadelphia.53 Previous research has demonstrated decreased HIV risk because of differences in drug preparation between black tar heroin users and powder heroin users.53 Our analysis was unable to account for differences in perceived HIV risk from syringe sharing as a result of drug market variability. In addition, we were unable to account for unmeasured variables associated with the rise of the opioid epidemic, including fentanyl use, expanding drug markets, overdose rates, and programs and policies implemented in response to these public health challenges. It is impossible to know for certain how the omission of these variables from multivariable analyses affected the direction and magnitude of the observed associations when compared with the true association between policy change and syringe-sharing behaviors.
Third, HIV and HCV status were not included in analyses because of changes in NHBS-funded testing by year of study and missing data on self-reported status. Exclusion of these variables from analyses is a limitation to the study if a true difference in syringe-sharing behaviors existed for persons with HIV or HCV infection compared with persons without either infection. Lastly, generalizability was limited because our results were not weighted, allowing for potential oversampling, including by race/ethnicity, age, and geography.
Conclusions
Findings from this study should be considered when reevaluating the public health impact of laws and policies on SSPs and syringe access. Trends in HIV diagnoses and overdose deaths may be used in conjunction with trends in syringe access policies and sharing to help identify cities or regions at increased risk for HIV outbreaks. Some US counties that are the most vulnerable to the rapid spread of HIV and HCV infections among PWID lack legal protection for syringe access.54,55 Persistent risk behaviors, demonstrated by increasing rates of HCV infection across the country56 and recent HIV outbreaks among PWID,57,58 indicate that PWID are at high risk for HIV acquisition despite comprising a smaller proportion of new diagnoses than observed historically. Removing barriers to syringe access and possession corresponded to reduced odds in injection works sharing and syringe sharing over time. For communities that are unable to change their laws, expanding access to sterile syringes, regardless of legality, can reduce the odds of sharing injection works and syringes.
Acknowledgments
The authors thank Toby LeRoux, Laura Weinberg, and Jesse Carlson for their contributions to the development of the local questions and for their data collection and field site supervision efforts; Lucy Alderton for her data management efforts in Denver; field staff and data management staff members in New Orleans; Nicole Bundy, Rafael Melecio, Dolicia Dobbs, and Paul Yarbor for their efforts in the field; and Joella Adams for data management efforts in Philadelphia. We also thank the reviewers for their constructive and helpful comments and ideas.
Footnotes
Declaration of Conflicting Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding: This journal article was supported by grants U1BP PS003251 (Denver), 5NU62PS005081 (New Orleans), and 6NU62PS005088 (Philadelphia), funded by the Centers for Disease Control and Prevention (CDC). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of CDC or the US Department of Health and Human Services.
References
- 1. Centers for Disease Control and Prevention Diagnoses of HIV infection in the United States and dependent areas, 2016. HIV Surveill Rep. 2017;28:1-125. [Google Scholar]
- 2. Rudd RA., Seth P., David F., Scholl L. Increases in drug and opioid-involved overdose deaths—United States, 2010-2015 [published correction appears in MMWR Morb Mortal Wkly Rep. 2017;66(1):35. doi:10.15585/mmwr.mm6601a10]. MMWR Morb Mortal Wkly Rep. 2016;65(50-51):1445-1452. doi:10.15585/mmwr.mm655051e1 [DOI] [PubMed] [Google Scholar]
- 3. Abdul-Quader AS., Feelemyer J., Modi S. et al. Effectiveness of structural-level needle/syringe programs to reduce HCV and HIV infection among people who inject drugs: a systematic review. AIDS Behav. 2013;17(9):2878-2892. 10.1007/s10461-013-0593-y [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4. Aspinall EJ., Nambiar D., Goldberg DJ. et al. Are needle and syringe programmes associated with a reduction in HIV transmission among people who inject drugs: a systematic review and meta-analysis. Int J Epidemiol. 2014;43(1):235-248. 10.1093/ije/dyt243 [DOI] [PubMed] [Google Scholar]
- 5. Jones L., Pickering L., Sumnall H., McVeigh J., Bellis MA. Optimal provision of needle and syringe programmes for injecting drug users: a systematic review. Int J Drug Policy. 2010;21(5):335-342. 10.1016/j.drugpo.2010.02.001 [DOI] [PubMed] [Google Scholar]
- 6. MacArthur GJ., van Velzen E., Palmateer N. et al. Interventions to prevent HIV and hepatitis C in people who inject drugs: a review of reviews to assess evidence of effectiveness. Int J Drug Policy. 2014;25(1):34-52. 10.1016/j.drugpo.2013.07.001 [DOI] [PubMed] [Google Scholar]
- 7. Palmateer N., Kimber J., Hickman M., Hutchinson S., Rhodes T., Goldberg D. Evidence for the effectiveness of sterile injecting equipment provision in preventing hepatitis C and human immunodeficiency virus transmission among injecting drug users: a review of reviews. Addiction. 2010;105(5):844-859. 10.1111/j.1360-0443.2009.02888.x [DOI] [PubMed] [Google Scholar]
- 8. Drucker E., Lurie P., Wodak A., Alcabes P. Measuring harm reduction: the effects of needle and syringe exchange programs and methadone maintenance on the ecology of HIV. AIDS. 1998;12(suppl A):S217-S230. [PubMed] [Google Scholar]
- 9. Keene J., Stimson GV., Jones S., Parry-Langdon N. Evaluation of syringe-exchange for HIV prevention among injecting drug users in rural and urban areas of Wales. Addiction. 1993;88(8):1063-1070. 10.1111/j.1360-0443.1993.tb02125.x [DOI] [PubMed] [Google Scholar]
- 10. Strathdee SA., Celentano DD., Shah N. et al. Needle-exchange attendance and health care utilization promote entry into detoxification. J Urban Health. 1999;76(4):448-460. 10.1007/BF02351502 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11. Hagan H., McGough JP., Thiede H., Hopkins S., Duchin J., Alexander ER. Reduced injection frequency and increased entry and retention in drug treatment associated with needle-exchange participation in Seattle drug injectors. J Subst Abuse Treat. 2000;19(3):247-252. 10.1016/S0740-5472(00)00104-5 [DOI] [PubMed] [Google Scholar]
- 12. Bastos FI., Strathdee SA. Evaluating effectiveness of syringe exchange programmes: current issues and future prospects. Soc Sci Med. 2000;51(12):1771-1782. 10.1016/S0277-9536(00)00109-X [DOI] [PubMed] [Google Scholar]
- 13. Lorvick J., Bluthenthal RN., Scott A. et al. Secondary syringe exchange among users of 23 California syringe exchange programs. Subst Use Misuse. 2006;41(6-7):865-882. 10.1080/10826080600669041 [DOI] [PubMed] [Google Scholar]
- 14. Huo D., Bailey SL., Hershow RC., Ouellet L. Drug use and HIV risk practices of secondary and primary needle exchange users. AIDS Educ Prev. 2005;17(2):170-184. 10.1521/aeap.17.3.170.62900 [DOI] [PubMed] [Google Scholar]
- 15. Patel MR., Foote C., Duwve J. et al. Reduction of injection-related risk behaviors after emergency implementation of a syringe services program during an HIV outbreak. J Acquir Immune Defic Syndr. 2018;77(4):373-382. 10.1097/QAI.0000000000001615 [DOI] [PubMed] [Google Scholar]
- 16. Centers for Disease Control and Prevention Syringe services programs for HIV prevention. Accessed January 3, 2019 https://www.cdc.gov/vitalsigns/hiv-drug-use/index.html
- 17. Golub ET., Bareta JC., Mehta SH., McCall LD., Vlahov D., Strathdee SA. Correlates of unsafe syringe acquisition and disposal among injection drug users in Baltimore, Maryland. Subst Use Misuse. 2005;40(12):1751-1764. 10.1080/10826080500259513 [DOI] [PubMed] [Google Scholar]
- 18. Sherman SG., Patel SA., Ramachandran DV. et al. Consequences of a restrictive syringe exchange policy on utilisation patterns of a syringe exchange program in Baltimore, Maryland: implications for HIV risk. Drug Alcohol Rev. 2015;34(6):637-644. 10.1111/dar.12276 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19. Fernández-Viña MH., Prood NE., Herpolsheimer A., Waimberg J., Burris S. State laws governing syringe services programs and participant syringe possession, 2014-2019. Public Health Rep. 2020;135(suppl 1):128S-137S. 10.1177/0033354920921817 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20. Downing M., Riess TH., Vernon K. et al. What’s community got to do with it? Implementation models of syringe exchange programs. AIDS Educ Prev. 2005;17(1):68-78. 10.1521/aeap.17.1.68.58688 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21. Gostin LO. The legal environment impeding access to sterile syringes and needles: the conflict between law enforcement and public health. J Acquir Immune Defic Syndr Hum Retrovirol. 1998;18(suppl 1):S60-S70. 10.1097/00042560-199802001-00012 [DOI] [PubMed] [Google Scholar]
- 22. Bluthenthal RN., Heinzerling KG., Anderson R., Flynn NM., Kral AH. Approval of syringe exchange programs in California: results from a local approach to HIV prevention. Am J Public Health. 2008;98(2):278-283. 10.2105/AJPH.2005.080770 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 23. Meyerson BE., Lawrence CA., Miller L. et al. Against the odds: syringe exchange policy implementation in Indiana. AIDS Behav. 2017;21(4):973-981. 10.1007/s10461-017-1688-7 [DOI] [PubMed] [Google Scholar]
- 24.Indiana Code Title 16, Art 41, Ch 7.5, Senate Enrolled Act 461.
- 25. Kerr T., Small W., Buchner C. et al. Syringe sharing and HIV incidence among injection drug users and increased access to sterile syringes. Am J Public Health. 2010;100(8):1449-1453. 10.2105/AJPH.2009.178467 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26. Ruiz MS., O’Rourke A., Allen ST. Impact evaluation of a policy intervention for HIV prevention in Washington, DC. AIDS Behav. 2016;20(1):22-28. 10.1007/s10461-015-1143-6 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 27. Executive Order No. 4-92 in Philadelphia. July 27, 1992. Accessed April 13, 2020 https://www.phila.gov/ExecutiveOrders/Executive%20Orders/4-92.pdf
- 28. Denver Public Health HIV behavioral surveillance in the Denver metro area: understanding HIV risk & prevention behaviors among persons who inject drugs. 2014. Accessed April 9, 2020 http://www.denverpublichealth.org/-/media/dph-files-and-docs/clinics-and-services/hiv/dph-nhbs-idu-denver-summary-report-20180730.pdf?la=en&hash=0F695931553D0CDFE062DBA1A385F550F59ABC82
- 29. Human Rights Watch In harm’s way: state response to sex workers, drug users and HIV in New Orleans. Published 2015. Accessed January 16, 2019 https://www.hrw.org/report/2013/12/11/harms-way/state-response-sex-workers-drug-users-and-hiv-new-orleans
- 30. Woodward A. Clean needle programs allowed under New Orleans City Council measure. The Advocate. December 15, 2017. Accessed April 9, 2020 https://www.nola.com/gambit/news/the_latest/article_05a02fdd-6738-5d0d-8d0d-8ce132d5ba6c.html
- 31. Centers for Disease Control and Prevention, National HIV Behavioral Surveillance Team Model Surveillance Protocol, Injecting Drug Users (NHBS-IDU3), Heterosexuals at Increased Risk of HIV (NHBS-HET3). 2011. Accessed April 9, 2020 https://www.cdc.gov/hiv/pdf/statistics/systems/nhbs/nhbs-idu3_nhbs-het3-protocol.pdf
- 32. Gallagher KM., Sullivan PS., Lansky A., Onorato IM. Behavioral surveillance among people at risk for HIV infection in the U.S.: the National HIV Behavioral Surveillance System. Public Health Rep. 2007;122(suppl 1):32-38. 10.1177/00333549071220S106 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 33. Lansky A., Abdul-Quader AS., Cribbin M. et al. Developing an HIV behavioral surveillance system for injecting drug users: the National HIV Behavioral Surveillance System. Public Health Rep. 2007;122(suppl 1):48-55. 10.1177/00333549071220S108 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 34. Centers for Disease Control and Prevention About multiple cause of death, 1999-2018. Accessed August 5, 2019 http://wonder.cdc.gov/mcd-icd10.html
- 35. Hood JE., Buskin SE., Dombrowski JC. et al. Dramatic increase in preexposure prophylaxis use among MSM in Washington State. AIDS. 2016;30(3):515-519. 10.1097/QAD.0000000000000937 [DOI] [PubMed] [Google Scholar]
- 36. Burt RD., Thiede H. Evaluating consistency in repeat surveys of injection drug users recruited by respondent-driven sampling in the Seattle area: results from the NHBS-IDU1 and NHBS-IDU2 surveys. Ann Epidemiol. 2012;22(5):354-363. 10.1016/j.annepidem.2012.02.012 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 37. Armitage P. Tests for linear trends in proportions and frequencies. Biometrics. 1955;11(3):375-386. 10.2307/3001775 [DOI] [Google Scholar]
- 38. World Health Organization International Statistical Classification of Diseases and Related Health Problems, Tenth Revision. World Health Organization; 1992. [PubMed] [Google Scholar]
- 39. Wejnert C., Hess KL., Hall HI. et al. Vital signs: trends in HIV diagnoses, risk behaviors, and prevention among persons who inject drugs—United States. MMWR Morb Mortal Wkly Rep. 2016;65(47):1336-1342. 10.15585/mmwr.mm6547e1 [DOI] [PubMed] [Google Scholar]
- 40. Wodak A., Cooney A. Do needle syringe programs reduce HIV infection among injecting drug users: a comprehensive review of the international evidence. Subst Use Misuse. 2006;41(6-7):777-813. 10.1080/10826080600669579 [DOI] [PubMed] [Google Scholar]
- 41. Lee K. Denver’s first legal needle exchange on horizon. The Denver Post. April 11, 2011. Accessed April 9, 2020 https://www.denverpost.com/2011/04/11/denvers-first-legal-needle-exchange-on-horizon
- 42. State Board of Pharmacy, 49 Pa. Code Ch. 27, Sales of Hypodermic Needles and Syringes. Pennsylvania Bull. 2009;39(37):5312-5314. Accessed April 17, 2020 http://www.pacodeandbulletin.gov/secure/pabulletin/data/vol39/39-37/39-37.pdf
- 43. Siddiqui SS., Armenta R., Evans JL. et al. Effect of legal status of pharmacy syringe sales on syringe purchases by persons who inject drugs in San Francisco and San Diego, CA. Int J Drug Policy. 2015;26(11):1150-1157. 10.1016/j.drugpo.2015.06.002 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 44. Costenbader EC., Zule WA., Coomes CC. Racial differences in acquisition of syringes from pharmacies under conditions of legal but restricted sales. Int J Drug Policy. 2010;21(5):425-428. 10.1016/j.drugpo.2009.12.006 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 45. Rudolph AE., Crawford ND., Ompad DC., Benjamin EO., Stern RJ., Fuller CM. Comparison of injection drug users accessing syringes from pharmacies, syringe exchange programs, and other syringe sources to inform targeted HIV prevention and intervention strategies. J Am Pharm Assoc (2003). 2010;50(2):140-147. 10.1331/JAPhA.2010.09193 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 46. Compton WM., Cottler LB., Decker SH., Mager D., Stringfellow R. Legal needle buying in St. Louis. Am J Public Health. 1992;82(4):595-596. 10.2105/AJPH.82.4.595 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 47. Cooper HLF., Bossak BH., Tempalski B., Friedman SR., Des Jarlais DC. Temporal trends in spatial access to pharmacies that sell over-the-counter syringes in New York City health districts: relationship to local racial/ethnic composition and need. J Urban Health. 2009;86(6):929-945. 10.1007/s11524-009-9399-7 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 48. Rockwell R., Des Jarlais DC., Friedman SR., Perlis TE., Paone D. Geographic proximity, policy and utilization of syringe exchange programmes. AIDS Care. 1999;11(4):437-442. 10.1080/09540129947811 [DOI] [PubMed] [Google Scholar]
- 49. Williams CT., Metzger DS. Race and distance effects on regular syringe exchange program use and injection risks: a geobehavioral analysis. Am J Public Health. 2010;100(6):1068-1074. 10.2105/AJPH.2008.158337 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 50. Cooper HLF., Des Jarlais DC., Ross Z., Tempalski B., Bossak B., Friedman SR. Spatial access to syringe exchange programs and pharmacies selling over-the-counter syringes as predictors of drug injectors’ use of sterile syringes. Am J Public Health. 2011;101(6):1118-1125. 10.2105/AJPH.2009.184580 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 51. Belani H., Chorba T., Fletcher F. et al. Integrated prevention services for HIV infection, viral hepatitis, sexually transmitted diseases, and tuberculosis for persons who use drugs illicitly: summary guidance from CDC and the U.S. Department of Health and Human Services. MMWR Recomm Rep. 2012;61(RR-5):1-40. [PubMed] [Google Scholar]
- 52. Burt RD., Hagan H., Sabin K., Thiede H. Evaluating respondent-driven sampling in a major metropolitan area: comparing injection drug users in the 2005 Seattle area National HIV Behavioral Surveillance System Survey with participants in the RAVEN and Kiwi studies. Ann Epidemiol. 2010;20(2):159-167. 10.1016/j.annepidem.2009.10.002 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 53. Ciccarone D., Bourgois P. Explaining the geographical variation of HIV among injection drug users in the United States. Subst Use Misuse. 2003;38(14):2049-2063. 10.1081/JA-120025125 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 54. Van Handel MM., Rose CE., Hallisey EJ. et al. County-level vulnerability assessment for rapid dissemination of HIV or HCV infections among persons who inject drugs, United States. J Acquir Immune Defic Syndr. 2016;73(3):323-331. 10.1097/QAI.0000000000001098 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 55. Burris S. Syringe possession laws. Updated July 2017. Accessed February 24, 2019 http://lawatlas.org/datasets/paraphernalia-laws
- 56. Centers for Disease Control and Prevention Viral hepatitis surveillance—United States, 2014. Accessed March 27, 2019 http://www.cdc.gov/hepatitis/statistics/2014surveillance/commentary.htm#summary
- 57. Conrad C., Bradley HM., Broz D. et al. Community outbreak of HIV infection linked to injection drug use of oxymorphone—Indiana, 2015. MMWR Morb Mortal Wkly Rep. 2015;64(16):443-444. [PMC free article] [PubMed] [Google Scholar]
- 58. CDC joins Department of Public Health in investigating HIV cluster among people who inject drugs [press release] Massachusetts Department of Public Health; April 5, 2018. Accessed April 15, 2019 https://www.mass.gov/news/cdc-joins-department-of-public-health-in-investigating-hiv-cluster-among-people-who-inject