Capturing Missed HIV Pre-exposure Prophylaxis Opportunities – Sexually Transmitted Infection Diagnoses in the Emergency Department

Abstract

The United States Centers for Disease Control and Prevention (CDC) recommends HIV Pre-exposure Prophylaxis (PrEP) be considered for all patients diagnosed with a sexually transmitted infection (STI). Emergency departments (ED) are an important site for diagnosis and treatment of STIs for underserved populations. Consequently, we identified 377 patients diagnosed with a bacterial STI (gonorrhea, chlamydia, and/or syphilis) at a major New York City ED between 1/1/2014–7/30/2017 to examine associations between key sociodemographic characteristics and missed opportunities for PrEP provision. In this sample, 299 (79%) ED patients missed their medical follow-up 90-days after STI diagnosis, as recommended. Results from adjusted generalized estimating equation regression models indicate that patients >45yo (aOR=2.2, 95%CI 1.2–3.9) and those with a primary care provider (PCP) in the hospital system (aOR=6.8, 95%CI 3.8–12.0) were more likely to return for follow-up visits whereas Black patients (aOR=0.44, 95%CI 0.25–0.77) were less likely to return for follow-up visits. These findings indicate that lack of STI treatment follow-up visits are significant missed opportunities for PrEP provision and comprehensive HIV prevention care.

Introduction

There are approximately 1.1 million Americans at risk for HIV infection, of whom only a small proportion (~8%) are prescribed pre-exposure prophylaxis (PrEP)¹. Daily adherence to PrEP has been shown to effectively prevent HIV infection across all populations with minimal safety risks². To achieve the Ending the HIV Epidemic (ETE) goals across the US, expansion beyond HIV testing and treatment to primary prevention by identifying individuals who would benefit from PrEP must be prioritized with novel interventions.

One point to engage individuals at heightened risk for HIV and linkage to PrEP services is within emergency departments (EDs). EDs are important sites for HIV testing as well as diagnosis and treatment of bacterial sexually transmitted infections (STIs), particularly among individuals who experience social and structural barriers to accessing comprehensive sexual health care^3,4. The US Centers for Disease Control and Prevention (CDC) recommends routine follow-up and re-testing once a bacterial STI is diagnosed and treated⁵. Specifically, patients diagnosed with chlamydia or gonorrhea should be scheduled for follow-up within three months (90-days) of treatment, those with pharyngeal gonococcal infection^6,7 within 7–14 days after diagnosis as a “test-of-cure,” and those with syphilis within 6-months of diagnosis - although closer evaluation may be indicated if the opportunity for follow up is uncertain⁷. Further, CDC guidelines recommend medical providers offer PrEP^8,9 to HIV-negative patients diagnosed with a bacterial STI, as these individuals are considered PrEP eligible. While the ED represents a highly heterogenous patient population, a recent study conducted in two Washington, DC EDs demonstrated a high number of PrEP eligible patients accessing their services, with over half (52%) indicating a desire to learn more about PrEP¹⁰.

As the number of STI cases continue to increase¹¹, concomitant increases in patients accessing EDs for STI evaluation and treatment are anticipated¹². Thus, EDs represent an important site for identifying PrEP eligible patients who may be interested in PrEP as means of HIV primary prevention and linking these individuals to appropriate HIV prevention care. Additional information on patients who present to EDs for STI testing and miss opportunities for further follow-up and engagement in PrEP services is warranted. Thus, the objective of this study was to identify characteristics of HIV-negative patients who missed follow-up care after a bacterial STI diagnosis and therefore represent missed opportunities to be prescribed PrEP at a major New York City safety-net hospital ED.

Methods

For this retrospective cohort study, we reviewed data on all patients presenting to the ED at Health + Hospitals (H+H)/Bellevue Hospital, a member of the NYC H+H system, who received HIV testing at least once during the study period from January 1, 2014 through July 30, 2017. Patients were included in the study if they tested positive for at least one of the following bacterial STIs: Chlamydia trachomatis, Neisseria gonorrhoeae, or Treponema pallidum during a visit to the ED at NYC H+H/Bellevue, were ≥18 years old, and had a negative HIV antibody test at the time of study entry. Gonorrhea and chlamydia testing were performed via nucleic acid amplification testing as per standard clinic-based testing protocols. A diagnosis of active syphilis required both a positive rapid plasma reagin (RPR) and a treponemal-specific test. Bacterial STI diagnoses are made 24 to 48 hours after the specimen is obtained, followed by patient notification by ED staff at the time the positive result is posted in the medical record. Demographic characteristics, laboratory tests, and PrEP prescriptions data were collected during the ED visit.

Between 1/1/2014 – 7/30/2017, 1,402 patients received a HIV-seronegative test result of whom 383 (27.3%) received at least one positive bacterial STI test. Among these 383 HIV-seronegative patients with at least one positive bacterial STI diagnosis, n=6 (1.6%) received a PrEP prescription during follow-up. We excluded these n=6 individuals from the analytic sample in order to describe the n=377 who were eligible but did not receive PrEP. Finally, among these n=377 individuals, n=365 patients presented at the ED for 1 visit for STI testing, 10 patients presented for 2 visits for STI testing, and 2 patients presented for 3 visits yielding a total of 403 patient-visits.

The main outcome for this study is a missed follow-up visit within 90-days of STI testing as it is a marker for a missed opportunity to engage these patients in HIV prevention care and prescribe PrEP. A 90-day follow-up period was selected as most patients (96%) tested positive for multiple bacterial STIs, including either gonorrhea or chlamydia at their ED visit and would require medical follow-up within this timeframe. Generalized estimating equation (GEE) regression models¹³ using a logit link to account for repeated, within-patient measures, were employed to examine sociodemographic and healthcare related factors for their association with a missed follow-up visit ≤90 days after STI diagnosis. Finally, Institutional Review Board (IRB) approval for this study was received from both New York University Langone Health School of Medicine IRB and the NYC H+H/Bellevue Research Office.

Results

In this sample of n=377 ED patients, 39% (148) of the sample was >45 years old, 66% (248) of the sample self-identified as male, and 51% (192) self-identified as Black (non-Hispanic), 39% (148) self-identified as Hispanic/Latinx, and 10% (39) self-identified as White (non-Hispanic). In addition, 88% (333) of this sample reported not having any health insurance coverage and 63% (239) of patients reported having a primary care provider (PCP) at H+H/Bellevue. By type of bacterial STI, 58.4% (220) patients tested positive for chlamydia, 85% (321) patients tested positive for gonorrhea, and 53% (198) patients tested positive for syphilis at their first visit during this study period. Overall, 79% (299) of patients did not have medical follow-up within 90 days after a positive STI diagnosis in the ED. In bivariable analysis, there were statistically significant differences in missed follow-up visits by race/ethnicity, health insurance status, having a medical provider at H+H/Bellevue (Table 1).

Table 1.

Demographic characteristics, healthcare factors and STI diagnoses by follow-up visit status among emergency department patients testing positive for bacterial STIs, 2014 – 2017

	Total n=377 (%)	Follow-up n=78 (%)	No follow-up n=299 (%)	p-value
Age (years)  18–24  25–34  35–44  45–54  55+	79 (21) 98 (26) 52 (14) 82 (22) 66 (18)	16 (21) 19 (24) 8 (10) 18 (23) 17 (22)	63 (21) 79 (26) 44 (15) 64 (21) 49 (16)	0.72
Sex at Birth  Male  Female	248 (66) 129 (34)	50 (64) 28 (36)	198 (66) 101 (34)	0.73
Race & Ethnicity  Non-Hispanic/Latinx White  Non-Hispanic/Latinx Black  Hispanic/Latinx	37 (10) 192 (51) 148 (39)	6 (8) 28 (36) 44 (56)	31 (10) 164 (55) 104 (35)	0.002
Health insurance  Uninsured  Medicare/Medicaid  Private	333 (88) 43 (11) 148 (39)	34 (44) 43 (55) 1 (1)	299 (100) 0 (0) 0 (0)	<0.001
Has Bellevue/H+H PCP  No  Yes	239 (63) 138 (37)	22 (28) 56 (72)	217 (73) 82 (27)	<0.001
Positive Chlamydia (initial visit)  No  Yes	220 (58) 157 (42)	46 (59) 32 (41)	174 (58) 125 (42)	0.91
Positive Gonorrhea (initial visit)  No  Yes	321 (85) 56 (15)	71 (91) 7 (9)	250 (84) 49 (16)	0.10
Positive Syphilis Diagnosis (initial visit)  No  Yes	198 (53) 179 (47)	36 (46) 42 (54)	162 (54) 137 (46)	0.21
Positive Diagnosis with 2 STIs (initial visit)  No  Yes	362 (96) 15 (4)	75 (96) 3 (4)	287 (96) 12 (4)	0.95

As shown in Table 2, in multivariable models adjusting for self-identified gender, ED patients who were >45 years old were more than 2-times as likely (aOR=2.2, 95% CI 1.2–3.9) and those with a PCP at H+H/Bellevue were more than 6-times as likely (aOR=6.8, 95% CI 3.8–12) to return for a medical follow-up within 90 days after diagnosis and treatment with a bacterial STI. However, individuals who self-identified as Black were 56% (aOR=0.44, 95% CI 0.25–0.77) less likely to return within 90 days for a STI medical follow-up.

Table 2.

Associations between demographic and healthcare factors with likelihood of returning for a follow-up visit among emergency department patients testing positive for bacterial STIs, 2014 – 2017

	Adjusted OR* (95% CI)
Age  ≤ 45  >45	Referent 2.2 (1.2–3.9)
Race/ethnicity  Black  All other race/ethnicities	0.44 (0.25–0.77) Referent
Have PCP within hospital system  No  Yes	Referent 6.8 (3.8–12.0)

^*controlling for self-identified gender

Discussion

Overall, our findings provide evidence of significant missed opportunities for linkage to PrEP services among individuals who test positive for a bacterial STI in the ED and who are at greater risk for HIV infection. Approximately 80% of patients with a bacterial STI did not return for follow-up within the recommended time frame. H+H/Bellevue is one of the largest safety net hospitals in the US. Our ED serves as a source of health care for individuals who lack medical insurance as well as those who face significant social and other structural barriers, which in turn limit their access to invaluable, primary health care services. Thus, missed follow-up appointments may represent missed opportunities for provision of comprehensive sexual healthcare services, including linkage to PrEP, for all who access the H+H/Bellevue ED.

Our findings do indicate that older patients, >45 yo, were more likely to return for an STI follow-up visit. This is an important consideration as epidemiologic trends indicate that risk of HIV seroconversion continues to increase among older adults and primary HIV prevention interventions targeting older efforts are less likely to be available for this age group¹⁴. Conversely, patients who were Black were less likely to return for follow-up medical care, as noted in an earlier study⁸. Efforts to increase provision of culturally competent care for Black and Indigenous People of Color (BIPOC) as well as identify better linkage to care after visits to the ED for STI treatment require particular attention. Novel methods to identify and refer those most in need of HIV prevention, such as EMR embedded risk calculator triggering discussion and ED prescription of PrEP described by Ridgway et al in 2018¹⁵, should also be considered to increase PrEP access, particularly in populations that face the greatest barriers to access. Leveraging existing EMR tools is especially important as it holds the potential to shift work from ED providers, who already practice in an environment where time is limited, and emergencies must be prioritized. Thus, efforts to facilitate the use of these existing EMR tools by ED providers can help identify and link PrEP eligible patients and serve as an important intervention point for HIV prevention.

Key study limitations must be considered before making final recommendations. First, information on follow-up visits outside of H+H/Bellevue were not available. Thus, patients who accessed the H+H/Bellevue ED for initial visits but sought follow-up care elsewhere may have had follow-up within 90 days that was not documented in our study. However, given that 88% of the sample was uninsured and only 11% had some form of public insurance, the degree of overestimating lack of follow-up visits is minimized. Additionally, syphilis diagnosis in this cohort was determined by a positive rapid plasma reagin (RPR) plus a positive treponemal-specific test; however, RPR titers were not compared within a patient overtime. As such, we likely overestimated active syphilis diagnoses within our analysis; our definition may have misclassified some patients with past, treated syphilis.

Other studies have documented the utilization of ED care for the diagnosis and treatment of STIs⁴. However, ours is the first study to assess follow-up visits after an ED diagnosed bacterial STI as a point of linkage to PrEP services. Ambulatory clinics across the US have been forced to significantly decrease in-person visits in the setting of the covid-19 pandemic, creating a chain reaction of limited access to medical providers and disengagement in routine timely care. Patients seeking sexual health services, including screening for STIs and HIV, may access EDs¹⁶. The need for robust STI screening, and linkage back to primary care for sexual healthcare services after an ED visit is critical to preventing new HIV infections. Emergency Departments and ED providers have the potential to serve as key stakeholders and points of health interventions to close the gap in HIV prevention. Instituting efforts to enhance retention in comprehensive sexual and HIV related healthcare, including linkage and prescription to PrEP, can bring us closer to ending the HIV epidemic.