Among a sexual minority and predominantly racial/ethnic minority population of MSM living with HIV, nearly 85% had evidence of sustained viral suppression. Our analyses resulted in four important findings. First, young MSM were significantly less likely to achieve sustained viral suppression. Second, racial disparities existed in sustained viral suppression, with Black MSM significantly less likely to achieve sustained viral suppression when compared with White MSM. Third, MSM experiencing drug/alcohol use, mental health symptoms including difficulty sleeping, homelessness and reporting a need for transportation help to appointments were less likely to achieve sustained viral suppression. Finally, clients with providers serving a larger volume of RWP clients were more likely to achieve sustained viral suppression. Notably, neighborhood factors were not associated with sustained viral suppression.
Our rate of sustained viral suppression among MSM (84.4%) was higher than that reported in previous national studies [7, 13,14,15,16]. This may be due to a significant upward trend in sustained viral suppression overtime nationwide [13, 17] and among PLHIV enrolled in the Ryan White Program  since previous studies used data from 2009 to 2016 and our study used 2017 data. Furthermore, previous studies have focused on the general population of PLHIV. Studies have reported that sustained viral suppression is higher among men compared with women  and among MSM compared with all other HIV risk groups .
Our finding that young MSM had lower odds of sustained viral suppression is consistent with national studies of the general population of PLHIV [7, 9, 13,14,15]. A study of 33 United States jurisdictions with complete reporting of viral load tests found that in 2014, 13–24 year old PLHIV were more likely to have unsuppressed viral loads at both their first and last test of the year and were more likely to have worsening viral load status (first test suppressed and last test unsuppressed) compared with all other age groups . Further, a study of New York City HIV surveillance data found that younger PLHIV were more likely to have at least 2 consecutive viral loads ≥100,000 copies/mL . It is worth noting that a study by Mandgasar et al.  suggested that age gaps in viral suppression among Ryan White Program clients decreased 2010–2016, thus disparities may be declining. However, this finding was not specific to MSM.
We identified racial disparities in sustained viral suppression with Black MSM having lower odds of sustained viral suppression when compared with White MSM. Our finding in Florida is consistent with findings at the national level for the general population of PLHIV [7, 13,14,15]. Although sustained viral suppression among Blacks has increased significantly in recent years , our findings suggest that Blacks continue to be disproportionately affected by challenges in sustaining viral suppression. Nevertheless, a study of Ryan White Program clients found significant declines in the difference between Blacks and Whites who were virally suppressed from 2010 (13.0 percentage point difference) to 2016 (8.1 percentage point difference) . Worth noting, the percentage of undiagnosed infections is disproportionately higher among some groups including young MSM compared with older MSM and Black MSM compared with White MSM . Given rates of undiagnosed infection, our study may underestimate disparities in sustained viral suppression among MSM. In a post hoc analysis, we tested the interaction between age and race/ethnicity but found it to be nonsignificant (p-value 0.3084).
After disaggregating the indices of psychosocial factors, we found that alcohol and drug use, reporting that drugs resulted in problems, and reporting that drugs prevented ART adherence were associated with decreased odds of sustained viral suppression. We were unable to identify other studies that examined the effect of these drug and alcohol-use related variables on sustained viral suppression with the exception of a study that found that reporting injection drug use (IDU) as an HIV risk factor was associated with decreased odds of sustained viral suppression compared with MSM behavior . Of note, our study included 47 MSM that also reported IDU as an HIV risk exposure. Our findings are particularly important among MSM, as the prevalence of drug and alcohol use among this population is high , and drug use has been associated with poor ART adherence . A recent study suggested that anticipated substance use stigma is associated with ART adherence among drug users, even after controlling for severity of drug and alcohol use . MSM with HIV may experience multiple stigmas related to their sexual orientation, their HIV status and substance using behavior. Thus, addressing the compounded stigmas in this population may be one mechanism to target to increase sustained viral suppression.
Additionally, we found that feelings of anxiety or depression, difficulty sleeping, receiving or needing mental health services, as well as reporting homelessness were associated with decreased odds of sustained viral suppression. While studies have examined mental health  and homelessness [23, 26] as it relates to viral suppression at one given time, none have looked at these factors in relation to consistent viral suppression which requires long-term ART adherence. A study of homeless PLHIV receiving ART found that 31% of study participants discontinued ART. Among those who discontinued ART, only 51% were adherent to ART and 9% had viral loads < 400 copies/mL . Further, among clients of a Ryan White Part-A funded Care Coordination Program (CCP), viral suppression was higher among those who were homeless at baseline but who obtained stable housing post-baseline compared with those who remained homeless . It is important to discuss the interaction of these psychosocial factors (substance use, mental health, and homelessness) because MSM who report drug use or binge drinking are more likely to report having unstable living environments and having a severe mental health disorder . These factors appear to be harder to address as a previous study showed smaller decreases in viral suppression among Ryan White Program clients who experience unstable or temporary housing compared with those with stable housing over a 6-year period . Our study also suggests other social service’s needs, such as reporting a need for transportation help to appointments, may also affect sustained viral suppression consistent with barriers to linkage to HIV care identified in a qualitative study of US clinics .
Clients with providers serving a larger volume of RWP clients were more likely to achieve sustained viral suppression in our study. Our study was only able to measure the volume of RWP clients a physician sees, not the volume of all HIV patients. Our findings are consistent with several other studies that found HIV physician volume associated with HIV care and treatment outcomes [29,30,31]. Our findings may reflect provider experience with caring for PLHIV, or characteristics of the clinics in which they practice. Clinics with providers that serve a large volume of RWP clients likely also have medical case managers that are well versed in RWP requirements and who also have substantial expertise in serving a racial/ethnic diverse and low socioeconomic status population with significant social services needs and psychosocial barriers. Thus, more research is needed to better understand the role of physician characteristics in HIV outcomes. Additionally, other provider factors, which we were unable to measure, may also be important. A longitudinal cohort study in Baltimore among PLHIV with a history of injection drug use found that only having the same HIV provider > 90% of the time was associated with decreased odds of virologic failure .
Being enrolled in the ACA was associated with sustained viral suppression in our study. The effect of the ACA may be due to differences in income as clients must have an income of at least 100% of the federal poverty level (FPL) to be eligible for ACA. In post hoc analyses, we found that sustained viral suppression among those below 100% of FPL was 74.4% compared with 88.7% for those with incomes ≥100% of FPL (p-value < 0.0001). Of note, similar to our study, the two national studies by Crepaz et al.  and Bradley et al.  that found disparities in sustained viral suppression across age and race/ethnicity included only people receiving care. Bradley et al.  further controlled for ART prescription but disparities remained, suggesting factors other than access to care and treatment are important in sustained viral suppression such as the psychosocial factors identified in this study.
Finally, neighborhood factors were not associated with sustained viral suppression in our study. Our finding is inconsistent with one study of New York City surveillance data which suggested that while neighborhood poverty was not associated with achieving viral suppression, it was associated with lower likelihood of maintaining viral suppression after diagnosis . However, the literature on the effect of neighborhoods on viral suppression is mixed with some studies showing an association between residing in areas of high deprivation and poor viral suppression [34, 35], and others showing no association [36, 37]. It is possible that neighborhood units smaller than the ZIP code or other neighborhood characteristics not measured in this study, particularly perceptions of one’s neighborhood, may be important. For example, a study found an association between perceived neighborhood disorder and ART non-adherence .
Our study has several limitations. The RWP serves PLHIV who are uninsured; thus, they are not representative of all MSM living with HIV. A second limitation relates to our definition of sustained viral suppression. While we are able to confidently say that those with only 1 viral load test that was ≥200 copies/ml did not achieve sustained viral suppression, we had to exclude those with only 1 viral load of < 200 copies/ml. We decided to exclude these clients because with only 1 viral load test result, we were unable to determine whether they were consistently suppressed. We compared demographic variables for those with missing vs. no missing sustained viral suppression data and found that those with missing data were more likely to be 34 years old or younger (p-value <.0001), black (p-value 0.0027), US born (p-value <.0001), English speaking (p-value <.0001), and less likely to be enrolled in the Affordable Care Act, all factors associated with not achieving sustained viral suppression. Finally, data were collected by numerous medical case managers for the purposes of service delivery. Thus, psychosocial information, particularly data about substance/alcohol use and mental health, were not collected using validated questionnaires, clinical evaluation tools, or procedures, and included only dichotomous yes/no response options.