Substance use among HIV-infected individuals is strongly correlated with increased morbidity and mortality, with four out of ten AIDS deaths directly related to substance abuse nationally. Historically, lower income HIV-infected persons in the United States access needed services through programs funded by the Ryan White (RW) Care Act, which acts as the "payer of last resort" for primary medical and ancillary service needs. This study examines the effects of substance use on ancillary service gaps (calculated as the difference between needed and received services) among a representative sample of RW recipients in Los Angeles County, California. The four aims were to: 1) describe the socio-demographic and service utilization characteristics of the population, 2) describe the role substance use plays in predicting service gaps, 3) investigate the role both stimulant use, and increased number of substances used, played at predicting service gaps among substance users and 4) investigate if newly identified service gap clusters differed by substance use behavior. Data from the 2011 Los Angeles Coordinated HIV/AIDS Needs Assessment (LACHNA) was utilized. Applied Individual levels weighting adjusted the effective sample size from 400 to 18,951 persons, similar to the 19,915 RW recipients in the system during the surveillance period. Among this sample 30% (119 unweighted, 5,743 weighted) reported recent substance use. Outcome measures of interest included the presence of service gaps (logistic regression) and the number of service gaps reported (Poisson regression). Comparisons of service utilization and socio-demographics characteristics between substance users and non-users revealed important differences in not only the number of gaps reported, but by age, gender and employment status as well. A series of logistic regression analysis revealed a consistent elevated risk of reporting a service gap (RR range: 2.87-3.45) among substance users. A secondary Poisson regression revealed risks among substance users for reporting an additional gap was less robust (RR range: 0.89-1.30). Among substance users those reporting both stimulant user (RR range: 1.54-1.75) and increased number of substances used (RR range: 1.32-1.56) were at similar increased risks for reporting additional service gaps. Substance users also reported increased needs for services related to secondary medical support (e.g., oral health and psychiatric services) as well as financial and housing assistance (e.g., section 8 housing and emergency shelter). Additionally, increased risks were also reported for those with current mental health conditions, female substance users and those reporting past lapses in care across multiple groups and models. These finding suggest that Ryan White providers should expand dissemination of available services system wide, as well as target interventions to specific populations not receiving adequate support services. This will ensure recipients are able to obtain the full spectrum of eligible services.
