BACKGROUND: Proper HIV management and prevention requires adherence to the HIV care continuum, which consist of diagnosis, linkage to care, retention in care, initiation of antiretroviral therapy, and achievement of viral suppression. Using spatial analysis to detect geographic hot spots of attrition from these steps may identify how best to target at risk populations for interventions.
METHODS: Using the Georgia Enhanced HIV/AIDS Reporting System’s routinely collected HIV case/laboratory surveillance data, a cohort of persons diagnosed with HIV in 2010 and 2011 in Fulton, DeKalb, Gwinnett, Clayton, Douglas, and Cobb counties in Georgia, was selected with follow-up to 2013 (n=2339). Spatial patterns of poor outcomes within the HIV care continuum were analyzed using hot spot analysis (Getis-Ord Gi*) to identify geographic areas of significant, non-random clustering, or hot spots. Logistic regression models were used to evaluate associations among hot spots, demographic factors, and each outcome, controlling for age at diagnosis, sex at birth, race/ethnicity, and transmission risk. Outcomes of interest were not linked to care, not linked to care within 90 days, not retained in care, and not virally suppressed. Linkage to care was defined as 1 or more CD4 count or viral load test results post-diagnosis. Retention in care was defined as completion of at least 1 CD4 count and/or viral load test result in each 6-month period over 24 months post-linkage with at least 60 days between results. Viral suppression was defined as a HIV-1 viral load <200 copies/mL at the end of the 24-month period 120 days.
RESULTS: Of the 2339 persons in the sample, 2067 persons (88.4%) linked to care; 1295 persons (62.6%) linked to care within 90 days among those linked; 663 persons (32.1%) were retained in care among those linked; 326 persons (49.2%) were virally suppressed among those retained. Persons residing in geographic hot spots had higher odds to not link to care [adjusted odds ratio: 1.51 (95% confidence interval 1.04-2.21)], not link to care within 90 days [2.73 (1.28-5.83)], not retain in care [2.47 (1.43-4.26)], and not achieve viral suppression [2.72 (1.56-4.76)] than persons residing outside of hot spots in the follow-up period.
CONCLUSIONS: Spatial patterns associated with clustering of poor outcomes were strong independent predictors of linkage to care, retention in care, and viral suppression in the metro-Atlanta area. The findings provide further evidence for the use of spatial analyses as a tool for characterizing areas to improve along the HIV care continuum.