Abstract
Youth aged 13‒24, are less likely to be retained in HIV care and be virally suppressed than older age groups. This study aimed to assess predictors of retention in HIV care and viral suppression among a population-based cohort of youth (N=2,872) diagnosed with HIV between 1993 and 2014 in Florida. We used generalized estimating equations (GEE) to estimate prevalence ratios (PRs). Retention in care was defined as evidence of engagement in care (at least one laboratory test, physician visit, or antiretroviral therapy prescription refill), two or more times, at least three months apart during 2015. Viral suppression was defined as having evidence of a viral load <200 copies/mL among those in care during 2015. Among the 2,872 youth, 65.4% were retained in care, and among those in care, 65.0% were virally suppressed. Older youth (18‒24 years-old) and non-Hispanic Blacks (NHBs) were less likely to be retained in care; whereas those with male-to-male sexual HIV transmission, perinatal HIV transmission, living in low socioeconomic neighborhoods, and those diagnosed with AIDS before 2016 were more likely be retained in care. Those diagnosed with AIDS before 2016 and NHBs were less likely to be virally suppressed; whereas those with male-to-male sexual HIV transmission and foreign-born persons were more likely to be virally suppressed. Results suggest the need for targeted retention and viral suppression interventions for NHB youth, and older youth (18‒24 years-age).
Keywords: HIV, youth, retention, viral suppression, individual, neighborhood
Introduction
Youth (those aged 13‒24 years), account for a considerably high proportion of human immunodeficiency virus (HIV) diagnoses compared with other age groups. In 2015, youth accounted for 22% of newly diagnosed persons.1Florida ranked second in the nation for the rate of HIV diagnoses in 2014.2 Youth with HIV in Florida have the lowest level of viral suppression of any age group.2
Understanding the health outcomes of persons living with a diagnosis of HIV is important for prevention and care activities. In general, individuals flow along the five steps of the HIV care continuum: HIV diagnosis, linkage to care, retention in care, adherence to antiretroviral therapy (ART), and viral suppression (defined as viral load <200 copies/ml).2 Viral suppression is the goal of the care continuum and benefits the individual by slowing disease progression and increasing survival.4,5 It also benefits the community as virally suppressed individuals are less likely to transmit the virus to others.6 To achieve viral suppression, individuals should be retained in care and adhere to ART. Youth with HIV are the least likely of any age group to be linked to care and achieve viral suppression.1, 7–9
The likelihood of retention in care and viral suppression is associated with individual and neighborhood factors. Individual-level factors associated with retention and viral suppression include young age,1,7–9 belonging to a minority ethnic group,1poor health literacy, lack of transportation to appointments, and history of depression.10 Neighborhood-level factors such as socioeconomic deprivation,11,12 unstable housing,10,13 perceived lack of a youth-friendly clinic atmosphere,6 unemployment and racial segregation are also associated with HIV care outcomes.12
Many studies have assessed predictors of retention in HIV care and viral suppression.8,11,14–16 However, few studies have used a multilevel approach to concurrently assess neighborhood predictors. A multilevel approach is important because it accounts for for the correlation between individuals living in the same neighborhood. Two studies11,17 used a multilevel approach to predict factors associated with medication adherence and viral suppression. Older youth (18–24) and youth who had reported engaging in recent unprotected sex were less likely to be virally suppressed; whereas youth with a longer time since HIV diagnosis and youth with a high school education or greater were more likely to achieve viral suppression.11
The objective of the current study was to assess the individual and neighborhood factors associated with retention in care and viral suppression during 2015 among a population-based cohort of youth (13–24 years old) diagnosed with HIV during 1993–2014, and living with HIV in Florida during 2015.
Methods
Datasets
This retrospective cohort study combined two datasets. The first was de-identified individual-level data from the Florida Department of Health enhanced HIV/AIDS Reporting System (eHARS) that had been previously linked with data from the Ryan White Program and the AIDS Drug Assistance Program (ADAP). All viral load measurements are reportable in Florida, these data are also included in eHARS. Data on people living with HIV, aged 13–24 during 2015, diagnosed between 1993 and 2014, and met the Centers for Disease Control and Prevention (CDC) HIV surveillance case definition18 were extracted from this dataset. The second data source was 5-year estimates (2009–2013) of neighborhood-level data from the American Community Survey (ACS).
Individual-level variables
Individual-level data extracted from eHARS included race/ethnicity, year of HIV diagnosis, year of AIDS diagnosis, sex at birth, age at HIV diagnosis, mode of HIV transmission, birth country, year of death, current ZIP code of residence, retention in HIV care in 2015, results of the last viral load test in 2015, whether the person was diagnosed at a correctional facility, and whether the person was living in Florida in 2015. Race/ethnicity was categorized as non-Hispanic White (NHW), non-Hispanic Black (NHB), Hispanic, and others. Mode of HIV transmission was categorized as heterosexual transmission, male-to-male sexual transmission (MSM), injection drug use (includes injection drug use [IDU] only or IDU with male-to-male sexual contact), perinatal and other/unknown. Youth (13‒24 years old) who were diagnosed at a correctional facility (n=20), who died prior to January 1st 2016 (n=110), who were no longer living in Florida during 2015 (n=188), and whose ZIP code was missing or invalid (n=57) were excluded from the study, leaving 2,872 youth diagnosed with HIV in the dataset for analysis.
Neighborhood-level variables
Data on neighborhood-level socioeconomic status (SES) were obtained from the ACS by ZIP Code Tabulation Areas (ZCTA). ZCTAs are areal representations of United States Postal Service (USPS) ZIP Code service areas.19 Thirteen variables were extracted from ACS by ZCTA. We used principal component analyses to create a SES index (categorized into quartiles). The final SES index included 7 indicators, namely, percent below federal poverty level, median household income, percent of households with annual income <$15,000, percent of households with annual income ≥$150,000, income disparity, percent of population age ≥25 with less than a 12th grade education, and high-class work (managerial, business, science, and arts occupations).
Additionally, NHB density (percentage of NHB from total population and a proxy for segregation) and rural-urban status were extracted. NHB density was categorized into three levels (<25%, 25–50% and ≥50%). Rural-urban categorization was based on Categorization C Version 2.0 of Rural-Urban Commuting Area (RUCA) codes, developed by the University of Washington.20 Details of the neighborhood variables and procedure for calculation of SES index and rural-urban categorization are explained elsewhere.21
Outcome measurement
Outcomes of interest in this study were retention in care and viral suppression. Retention in care was defined as evidence of engagement in care two or more times, at least three months apart during 2015. Engagement in care was defined as evidence of at least one documented CD4 or viral load test, a prescription filled through ADAP, or a physician visit documented in one of the Ryan White Program databases. HIV viral load suppression was defined as having evidence of a viral load <200 copies/mL in the last laboratory test performed during 2015. The last viral load test during the measurement year is used by the U.S. Health Resources and Services Administration (HRSA) to measure Ryan White Program performance.22 Viral load suppression analysis was limited to those who were in care in 2015 (i.e. at least one laboratory test, physician visit, or receipt of ART medication during 2015).
Analysis
Individual- and neighborhood-level variables were merged by matching the current ZIP code of each person with the ZIP code’s corresponding ZCTA. All analyses were performed using SAS, version 9.4 (SAS Institute, 2011) using the GENMOD procedure. The log-binomial regression model (binomial distribution with logarithm link) did not converge. Therefore, we used Poisson regression modeling with robust error variance estimation provided by the generalized estimating equations (GEE) approach.23 First, we calculated the crude prevalence ratio (PR) for each variable separately for both outcomes (retention and viral suppression). Then we calculated the adjusted prevalence ratios (aPR) of each individual-level variable by simultaneously including all individual-level variables (year of HIV diagnosis, birth sex, race/ethnicity, current age group, birth country, mode of HIV transmission and AIDS status before 2016) in one model. Then we calculated the aPR of every individual- and neighborhood-level (SES index, rural-urban residence, and percent of NHB density) variable by simultaneously including them all in one model. Lastly, we tested the interaction between birth country and other covariates, and race/ethnicity and other covariates for both outcomes (retention in care and viral suppression).
The Florida International University Institutional Review Board approved this study, and the Florida Department of Health Institutional Review Board designated this study as nonhuman subjects research.
Results
Table 1 shows the demographic characteristics and outcomes of the population by age group. Most of the cohort was male (68.1%), NHB (68.7%), and U.S. born (84.7%). Of the 2,872-youth included in the analysis, 1,877 (65.4%) were retained in care, and 1405 (65.0%) of the 2,162 who were in care in 2015 were virally suppressed. In the bivariate analysis, there was a significant association between age group and year of HIV diagnosis, sex at birth, mode of HIV transmission, in care status during 2015, and retention in care during 2015.
Table 1.
Demographic characteristics of youth (13–24) by age group in 2015 diagnosed with HIV infection between 1993 and 2014, Florida.
| Age group | |||||
|---|---|---|---|---|---|
| Characteristics | Total population (N=2872) | 13–17 years (n= 251, 8.7%) | 18–20 years (n= 509, 17.7%) | 21–24 years (n=2112, 73.5%) | p-value* |
| Individual-level factors | |||||
| Year of HIV diagnosis | <.0001 | ||||
| 1993‒1999 | 464 (16.2) | 73 (29.1) | 154 (30.3) | 237 (11.2) | |
| 2000‒2004 | 188 (6.6) | 99 (39.4) | 28 (5.5) | 61 (2.9) | |
| 2005‒2009 | 299 (10.4) | 36 (14.3) | 34 (6.7) | 229 (10.8) | |
| 2010‒2014 | 1921 (66.9) | 43 (17.1) | 293 (57.6) | 1585 (75.1) | |
| Sex at birth | <.0001 | ||||
| Female | 917 (31.9) | 155 (61.8) | 212 (41.7) | 550 (26.0) | |
| Male | 1955 (68.1) | 96 (38.3) | 297 (58.4) | 1562 (74.0) | |
| Race/ethnicity | 0.4350 | ||||
| Non-Hispanic white | 306 (10.7) | 16 (6.4) | 41 (8.1) | 249 (11.8) | |
| Hispanic | 520 (18.1) | 33 (13.2) | 82 (16.1) | 405 (19.2) | |
| Non-Hispanic black | 1972 (68.7) | 195 (77.7) | 371 (72.9) | 1406 (66.6) | |
| Other | 74 (2.6) | 7 (2.8) | 15 (3.0) | 52 (2.5) | |
| US born | 0.7684 | ||||
| Yes | 2433 (84.7) | 216 (86.1) | 436 (85.7) | 1781 (84.3) | |
| No | 439 (15.3) | 35 (13.9) | 73 (14.3) | 331 (15.7) | |
| Mode of HIV transmission | <.0001 | ||||
| Heterosexual contact | 526 (18.3) | 10 (4.0) | 83 (16.3) | 433 (20.5) | |
| Injection drug usea | 38 (1.3) | 0 (0.0) | 0 (0.0) | 38 (1.8) | |
| Male-to-male sexual contact | 1390 (48.4) | 7 (2.8) | 172 (33.8) | 1211 (57.3) | |
| Perinatal | 803 (28.0) | 224 (89.2) | 235 (46.2) | 344 (16.3) | |
| Other/unknown | 115 (4.0) | 10 (4.0) | 19 (3.7) | 86 (4.1) | |
| AIDS before 2016 | 0.0084 | ||||
| Yes | 824 (28.7) | 82 (32.7) | 182 (35.8) | 560 (26.5) | |
| No | 2048 (71.3) | 169 (67.3) | 327 (64.2) | 1552 (73.5) | |
| In care 2015b | <.0001 | ||||
| Yes | 2162 (75.3) | 218 (86.8) | 417 (81.9) | 1527 (72.3) | |
| No | 710 (24.7) | 33 (13.2) | 92 (18.1) | 585 (27.7) | |
| Retention in care in 2015c | <.0001 | ||||
| Yes | 1877 (65.4) | 208 (82.9) | 365 (71.7) | 1304 (61.7) | |
| No | 995 (34.6) | 43 (17.1) | 144 (28.3) | 808 (38.3) | |
| Viral suppression among those in care (n=2162)d | 0.2244 | ||||
| Yes | 1405 (65.0) | 142 (65.1) | 256 (61.4) | 1007 (66.0) | |
| No | 757 (35.0) | 76 (34.9) | 161 (38.6) | 520 (34.1) | |
| Neighborhood-level factors | |||||
| SES index, quartilese | 0.3265 | ||||
| 1 (lowest) | 1377 (48.0) | 120 (47.8) | 263 (51.7) | 994 (47.1) | |
| 2 | 764 (26.6) | 75 (29.9) | 123 (24.2) | 566 (26.8) | |
| 3 | 456 (15.9) | 33 (13.2) | 82 (16.1) | 341 (16.2) | |
| 4 (highest) | 275 (9.6) | 23 (9.2) | 41 (8.1) | 211 (10.0) | |
| Rural/urban classification | 0.2866 | ||||
| Urban | 2757 (96.0) | 245 (97.6) | 491 (96.5) | 2021 (95.7) | |
| Rural | 115 (4.0) | 6 (2.4) | 18 (3.5) | 91 (4.3) | |
| Non-Hispanic black density | 0.0593 | ||||
| <25 | 1340 (46.7) | 109 (43.4) | 221 (43.4) | 1010 (47.8) | |
| 25–49% | 687 (23.9) | 65 (25.9) | 113 (22.2) | 509 (24.1) | |
| >50% | 845 (29.4) | 77 (30.7) | 175 (34.4) | 593 (28.1) | |
Abbreviations: AIDS: acquired immune deficiency syndrome; HIV: human immunodeficiency virus; US: United States; SES: socioeconomic status.
Includes persons with mode of transmission reported as injection drug use or injection drug use with male-to-male sexual contact.
Documentation of at least one HIV clinic visit through record of at least one viral load or CD4 count test, one Ryan White Program physician visit, or receipt of medication through AIDS Drug Assistance Program during 2015.
Documentation of at least two HIV clinic visits at least three months apart during 2015.
Viral load <200 copies/mL in the last laboratory test performed during 2015.
Quartiles of standardized SES scores.
p-value for individual level variables from Cochrane-Mantel-Haenszel chi square test controlling for ZCTA. p-value for neighborhood variables from chi square test.
Retention in care during 2015
Adjusting for individual- and neighborhood-level factors, those whose HIV infection was diagnosed between 2005 and 2009 were less likely to be retained in care (aPR 0.88, 95% confidence interval [CI] 0.79‒0.97) than those diagnosed between 2010 and 2014 (Table 2). Males were less likely to be retained in care compared with females (aPR 0.86, 95% CI 0.79‒0.93). Those aged 18–20 and 21–24 years were less likely to be retained in care (aPR 0.85, 95% CI 0.78‒0.93, and aPR 0.74, 95% CI 0.68‒0.80 respectively) compared to those aged 13–17. Compared to those reporting heterosexual mode of HIV transmission, those with MSM and perinatal HIV transmission were more likely to be retained in care (aPR 1.26, 95% CI 1.15‒1.39, and aPR 1.17, 95% CI 1.03‒1.33 respectively), whereas those with the other mode of HIV transmission were less likely to be retained in care (aPR 0.73, 95% CI 0.59‒0.91). Those diagnosed with AIDS before 2016 were more likely to be retained in care (aPR 1.22, 95% CI 1.16‒1.29).
Table 2:
Crude and adjusted prevalence ratios and 95% CI of retention in care during 2015 among youth (13‒24) diagnosed with HIV infection between 1993 and 2014 (N=2872)
| Total, n | Retained in care n,% | Crude PR (95% CI) | PR adjusted for individual-level factors (95% CI) | PR adjusted for individual-and neighborhood-level factors (95% CI) | |
|---|---|---|---|---|---|
| Individual-level factors | |||||
| Year of HIV diagnosis | |||||
| 1993–1999 | 464 | 331 (71.3) | 1.11 (0.99–1.23) | 0.90 (0.71–1.14) | 0.91 (0.80–1.03) |
| 2000–2004 | 188 | 141 (75.0) | 1.17 (0.98–1.39) | 0.92 (0.71–1.20) | 0.93 (0.82–1.06) |
| 2005–2009 | 299 | 175 (58.5) | 0.91 (0.78–1.07) | 0.87 (0.72–1.04) | 0.88 (0.79–0.97) |
| 2010–2014 | 1921 | 1230 (64.0) | Reference | Reference | Reference |
| Sex at birth | |||||
| Female | 917 | 625 (68.2) | Reference | Reference | Reference |
| Male | 1955 | 1252 (64.0) | 0.94 (0.85–1.03) | 0.86 (0.75–0.99) | 0.86 (0.79–0.93) |
| Race/ethnicity | |||||
| Non-Hispanic white | 306 | 213 (69.6) | Reference | Reference | Reference |
| Hispanic | 520 | 372 (71.5) | 1.03 (0.87–1.21) | 1.02 (0.86–1.21) | 1.02 (0.93–1.12) |
| Non-Hispanic black | 1972 | 1240 (62.9) | 0.90 (0.78–1.04) | 0.86 (0.74–1.00) | 0.88 (0.81–0.95) |
| Other | 74 | 52 (70.3) | 1.01 (0.74–1.36) | 0.97 (0.71–1.32) | 0.99 (0.85–1.16) |
| US born | |||||
| Yes | 2433 | 1598 (65.7) | Reference | Reference | Reference |
| No | 439 | 279 (63.6) | 0.97 (0.85–1.09) | 0.96 (0.84–1.10) | 0.96 (0.89–1.03) |
| Age group | |||||
| 13–17 | 251 | 208 (82.9) | Reference | Reference | Reference |
| 18–20 | 509 | 365 (71.7) | 0.87 (0.73–1.03) | 0.85 (0.70–1.02) | 0.85 (0.78–0.93) |
| 21–24 | 2112 | 1304 (61.4) | 0.74 (0.64–0.86) | 0.74 (0.61–0.88) | 0.74 (0.68–0.80) |
| Mode of HIV transmission | |||||
| Heterosexual contact | 526 | 303 (57.6) | Reference | Reference | Reference |
| Injection drug usea | 38 | 22 (57.9) | 1.01 (0.65–1.55) | 1.00 (0.64–1.55) | 1.00 (0.75–1.33) |
| Male-to-male sexual contact | 1398 | 919 (66.1) | 1.15 (1.01–1.31) | 1.26 (1.06–1.50) | 1.26 (1.15–1.39) |
| Perinatal | 803 | 585 (72.9) | 1.26 (1.10–1.45) | 1.18 (0.93–1.50) | 1.17 (1.03–1.33) |
| Other/unknown | 115 | 48 (41.7) | 0.72 (0.53–0.98) | 0.73 (0.54–1.00) | 0.73 (0.59–0.91) |
| AIDS before 2016 | |||||
| No | 2048 | 1265 (61.8) | Reference | Reference | Reference |
| Yes | 824 | 612 (74.3) | 1.20 (1.09–1.32) | 1.22 (1.10–1.36) | 1.22 (1.16–1.29) |
| Neighborhood‒level factors | |||||
| SES index, quartilesb | |||||
| 1 (lowest) | 1377 | 891 (64.7) | 1.04 (0.88–1.23) | 1.15 (1.02–1.30) | |
| 2 | 764 | 504 (66.0) | 1.06 (0.89–1.26) | 1.12 (0.99–1.26) | |
| 3 | 456 | 311 (68.2) | 1.10 (0.91–1.32) | 1.10 (0.97–1.24) | |
| 4 (highest) | 275 | 171 (62.2) | Reference | Reference | |
| Rural/urban classification | |||||
| Urban | 2757 | 1802 (65.4) | Reference | Reference | |
| Rural | 115 | 75 (65.2) | 1.00 (0.79–1.26) | 1.00 (0.88–1.13) | |
| Non-Hispanic black density | |||||
| <25 | 1340 | 916 (98.4) | Reference | Reference | |
| 25–49% | 687 | 438 (63.8) | 0.93 (0.83–1.05) | 0.94 (0.87–1.01) | |
| >50% | 845 | 523 (61.9) | 0.91 (0.81–1.01) | 0.90 (0.83–0.98) |
Abbreviations: AIDS: acquired immune deficiency syndrome; HIV: human immunodeficiency virus; US: United States; PR: prevalence ratio; CI: confidence interval; SES: socioeconomic status
Includes persons with mode of transmission reported as injection drug use or injection drug use with male-to-male sexual contact.
Quartiles of standardized SES scores.
With respect to the neighborhood-level factors, compared to living in the highest SES (4th quartile) areas, living in the low SES areas was associated with higher prevalence for retention in HIV care (aPR 1.15, 95% CI 1.02‒1.30). There was an interaction between race/ethnicity and living in NHB density areas for retention in care. In high NHB density areas, NHBs were less likely to be retained in care (aPR 0.72, 95% CI 0.59‒0.89) compared to NHWs. In medium NHB density areas, a similar NHB:NHW ratio was observed (aPR 0.70, 95% CI 0.61‒0.81). In the low NHB density areas, there was no difference in retention among NHWs, NHBs (aPR 0.94, 95% CI 0.85‒1.04). This effect modification by NHB density areas was not observed among Hispanics.
Viral suppression among those in care during 2015
Contrasting between those diagnosed between 2010 and 2014, those diagnosed between 2005 and 2009 were less likely to be virally suppressed (aPR 0.80, 95% CI 0.70‒0.91) (Table 3). Furthermore, NHBs and those categorized as other/unknown race/ethnicity were less likely to be virally suppressed (aPR 0.86, 95% CI 0.79‒0.94, and aPR 0.80, 95% CI 0.66‒0.96 respectively) as compared with NHWs. Those who were more likely virally suppressed were among the foreign-born (aPR 1.12, 95% CI 1.04‒1.21), and those with heterosexual mode of HIV transmission, (aPR 1.14, 95% CI 1.02‒1.28). Those diagnosed with AIDS before 2016 were less likely to be virally suppressed (aPR 0.82, 95% CI 0.76‒0.89). None of the neighborhood factors were associated with viral suppression.
Table 3:
Crude and adjusted prevalence ratio and 95% CI of viral suppression during 2015 among youth (13‒24) diagnosed with HIV infection between 1993 and 2014 who were in care in 2015 (N=2162)
| Total, n | Virally suppressed n,% | Crude PR | PR adjusted for individual-level factors (95% CI) | PR adjusted for individual-and neighborhood-level factors (95% CI) | |
|---|---|---|---|---|---|
| Individual-level factors | |||||
| Year of HIV diagnosis | |||||
| 1993–1999 | 377 | 202 (53.6) | 0.76 (0.65–0.88) | 0.88 (0.67–1.17) | 0.90 (0.75–1.07) |
| 2000–2004 | 156 | 92 (59.0) | 0.83 (0.67–1.03) | 0.86 (0.63–1.18) | 0.88 (0.74–1.05) |
| 2005–2009 | 208 | 107 (51.4) | 0.73 (0.60–0.89) | 0.78 (0.63–0.98) | 0.80 (0.70–0.91) |
| 2010–2014 | 1421 | 1004 (70.7) | Reference | Reference | Reference |
| Sex at birth | |||||
| Female | 727 | 424 (58.3) | Reference | Reference | Reference |
| Male | 1435 | 981 (68.4) | 1.17 (1.05–1.31) | 1.01 (0.85–1.19) | 1.00 (0.89–1.11) |
| Race/ethnicity | |||||
| Non-Hispanic white | 246 | 189 (76.8) | Reference | Reference | Reference |
| Hispanic | 410 | 313 (76.3) | 0.99 (0.83–1.19) | 0.95 (0.79–1.14) | 0.96 (0.88–1.05) |
| Non-Hispanic black | 1444 | 865 (59.9) | 0.78 (0.67–0.91) | 0.82 (0.70–0.96) | 0.86 (0.79–0.94) |
| Other | 62 | 38 (61.3) | 0.80 (0.56–1.13) | 0.79 (0.56–1.12) | 0.80 (0.66–0.96) |
| US born | |||||
| Yes | 1851 | 1167 (63.1) | Reference | Reference | Reference |
| No | 311 | 238 (76.5) | 1.12 (1.06–1.40) | 1.12 (0.96–1.30) | 1.12 (1.04–1.21) |
| Age group | |||||
| 13–17 | 218 | 142 (65.1) | Reference | Reference | Reference |
| 18–20 | 417 | 256 (61.4) | 0.94 (0.77–1.16) | 0.87 (0.69–1.09) | 0.87 (0.76–1.00) |
| 21–24 | 1527 | 1007 (65.9) | 1.01 (0.85–1.21) | 0.87 (0.70–1.08) | 0.87 (0.76–1.00) |
| Mode of HIV transmission | |||||
| Heterosexual contact | 374 | 222 (59.4) | Reference | Reference | Reference |
| Injection drug usea | 27 | 19 (70.4) | 1.19 (0.74–1.89) | 1.15 (0.72–1.86) | 1.15 (0.90–1.48) |
| Male-to-male sexual contact | 1048 | 755 (72.0) | 1.21 (1.05–1.41) | 1.15 (0.94–1.41) | 1.14 (1.02–1.28) |
| Perinatal | 655 | 369 (56.3) | 0.95 (0.80–1.12) | 1.08 (0.82–1.44) | 1.05 (0.89–1.24) |
| Other/unknown | 58 | 40 (69.0) | 1.16 (0.83–1.63) | 1.10 (0.78–1.55) | 1.08 (0.90–1.29) |
| AIDS before 2016 | |||||
| No | 1462 | 1035 (70.8) | Reference | Reference | Reference |
| Yes | 700 | 370 (52.9) | 0.75 (0.66–0.84) | 0.82 (0.72–0.93) | 0.82 (0.76–0.89) |
| Neighborhood-level factors | |||||
| SES index, quartilesb | |||||
| 1 (lowest) | 1020 | 619 (60.7) | 0.79 (0.66–0.94) | 0.90 (0.81–1.00) | |
| 2 | 595 | 391 (65.7) | 0.85 (0.71–1.03) | 0.90 (0.81–1.00) | |
| 3 | 348 | 242 (69.5) | 0.90 (0.74–1.12) | 0.91 (0.82–1.02) | |
| 4 (highest) | 199 | 153 (76.9) | Reference | Reference | |
| Rural/urban classification | |||||
| Urban | 2071 | 1341 (64.8) | Reference | Reference | |
| Rural | 91 | 64 (70.3) | 1.09 (0.84–1.40) | 1.08 (0.93–1.26) | |
| Non-Hispanic black density | |||||
| <25 | 1047 | 746 (71.3) | Reference | Reference | |
| 25–49% | 513 | 322 (62.8) | 0.88 (0.77–1.00) | 0.96 (0.88–1.04) | |
| >50% | 602 | 337 (56.0) | 0.79 (0.70–0.89) | 0.91 (0.81–1.01) | |
Abbreviations: AIDS: acquired immune deficiency syndrome; HIV: human immunodeficiency virus; US: United States; PR: prevalence ratio; CI: confidence interval; SES: socioeconomic status.
Includes persons with mode of transmission reported as injection drug use or injection drug use with male-to-male sexual contact.
Quartiles of standardized SES scores
Discussion
Among youth living with HIV in Florida, we found the prevalence of retention in HIV care to be 65.4%, and that of viral suppression among those in care to be 65.0%. Our study has additional important findings. First, NHB youth were less likely to be retained in care and virally suppressed compared with NHW youth. Second, compared to heterosexual mode of HIV transmission, MSM mode of HIV transmission was associated with better outcome in retention and viral suppression, and perinatal mode of HIV transmission was associated with better outcomes in retention but not with viral suppression. Third, youth aged 18–24 were less likely to be retained in care relative to those aged 13–17. Fourth, those diagnosed with AIDS before 2016 were more likely to be retained in care but less likely to be virally suppressed. Fifth, foreign-born were more likely to be virally suppressed. Lastly, living in low SES areas was associated with higher likelihood of being retained in care.
In 2015, 66.2% of youth diagnosed and living with HIV in Florida were retained in care, and 65% of those in care were virally suppressed (HIV/AIDS profile in Florida, HIV care continuum, unpublished data from Florida Department of Health). Of all PLWH in Florida in 2015, 76% were retained in care, and 79.9% of those in care had a suppressed viral load (HIV/AIDS profile in Florida, HIV care continuum, unpublished data from Florida Department of Health). Our study has similar finding with the report of HIV care continuum among youth in 2015 in Florida in that 65.4% of youth diagnosed and living with HIV in Florida (1993‒2014) were retained in care in 2015, and of those in care, 65% were virally suppressed. Our study also shows that those diagnosed between 2005 and 2009 were less likely to be retained in care and virally suppressed compared to those diagnosed between 2010 and 2014. This suggests improvement in retention in care and viral suppression across time. The viral suppression among youth living with HIV is low compared to all PLWH in Florida. Monitoring youth-specific progress on objectives and activities in the HIV/AIDS strategic plan is critical to ensuring success in HIV care continuum among youth in Florida.
Our study found that racial disparities in retention and viral suppression exist among youth living with HIV in Florida. The finding that NHB youth were less likely to be virally suppressed is consistent with another study conducted among youth in Chicago.24 A previous study among all ages between 2000–2014 using Florida HIV surveillance data also found lower odds of retention and viral suppression among NHB adults in Florida.25 Perceptions that patients are excluded from the health decision-making process, fear and medical distrust,26 experiences of racism, quality of provider relationships,27 and low insurance coverage28 could affect the engagement of NHBs in HIV care.
In this study, individuals with MSM mode of HIV transmission were more likely to be retained in care and virally suppressed. A study in a general population in Tennessee found similar results for viral suppression.29 Moreover, in our study, perinatal mode of transmission was associated with a higher likelihood of being retained in care. Kahana et al. reported higher rates of ART use among individuals with perinatal mode of HIV transmission.17 This could be due to comprehensive pediatric care, and early initiation of antiretroviral medication among those with a perinatal mode of HIV transmission.30
Compared with younger youth (13–17 years old), those aged 18–24 were less likely to be retained in care. This could be due to the transition from child-centered to adult-centered care.31 Logistical challenges related to health insurance and access to social services, psychosocial barriers, and stigma related to meeting new providers could also be reasons that may make this transition time more complex.32 Youth friendly services and adherence clubs that create supportive social environment and peer support can help to increase retention of youth in HIV care.33
Being diagnosed with AIDS before 2016 was associated with a higher likelihood of retention and lower likelihood of viral suppression. The fact that those who are symptomatic are more likely to seek medical care may explain the higher prevalence for being retained in care. This study did not assess adherence to ART, however, non-adherence to medication34 and the advanced nature of the disease35 could be reasons for the lower prevalence of those who had AIDS before 2016 being virally suppressed.
Considering immigration status (especially if undocumented) and the fact that foreign-born individuals are less likely to access health care, less likely to have health insurance and be less satisfied with the health care they receive,36 foreign-born youth would be expected to have a difficult time achieving viral suppression. Surprisingly, our study showed that foreign-born youth were more likely to achieve viral suppression. This result was consistent with the results from a nation-wide study of the general population within the U.S.37 Myers et al hypothesized that those who self-select for migration may have particular skills that enable them to successfully navigate healthcare systems, adhere to ART and maintain health-seeking behaviors after being diagnosed with HIV.37
Unexpectedly, living in low SES areas was associated with a higher likelihood of being retained in care. A previous study found that economic deprivation was inversely associated with residence in poor retention hot spots.38However, in our study, we could not adjust for individual SES. After adjustment for individual SES, the effect of neighborhood SES on health may not have been significant.39 In addition to this, it should be noted that an individuals’ SES may not necessarily coincide with the SES of the neighborhood they reside in.
The study by Kahana et al., 2016 found youth living in neighborhoods more densely populated by African Americans are less likely to report continued ART use.17 This is consistent with the lower prevalence of retention in care among those living in higher NHB density neighborhoods found in our study. This could be due to individual poverty levels, lack of education, stressful environment,40 lack of access to amenities.41 Further research is needed to explore the mechanisms by which high NHB density neighborhoods may be impacting success in engagement in care among youth.
To our knowledge, this is the first population-based study that examined individual and neighborhood-level determinants of retention in care and viral suppression among youth. The results of this study should be interpreted in the context of its limitations. First, we did not have individual-level socioeconomic variables which could have partially explained the disparities. Second, data about mode of HIV transmission and race/ethnicity were self-reported or abstracted from medical records leading to potential bias. Third, there may be higher ascertainment of retention in care among those enrolled in the Ryan White Program or ADAP relative to those not in those programs. This could lead to a smaller difference identified between those in low and those in high SES areas. Fourth, we do not have data about characteristics of the clinics the youth attended (e.g., available resources, provider-client relationship, and staff workloads), therefore these characteristics could confound the observed association.42
Conclusion
This study has identified individual- and neighborhood-level predictors of retention in care and viral suppression among youth living with HIV in Florida. Public health programs should address the disparities identified among youth found in this study. Activities to improve retention in care should target NHBs living in high NHB density areas, and youth aged 18–24 years. Activities to improve viral suppression should consider targeting NHBs. Further studies are needed to confirm and explore the reasons for the higher prevalence for viral suppression among foreign-born than U.S.-born youth in care. Moreover, our analysis used data from 2015; it will be important to assess these associations using current data.
Funding support
Research reported in this publication was supported by the National Institute on Minority Health and Health Disparities of the National Institutes of Health under Award Number K01MD013770. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
Footnotes
Declaration of Conflicting Interests
The Authors declare that there is no conflict of interest.
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