Identifying Subgroups of People Living With HIV in British Columbia, Canada Based on Sexually Transmitted and Blood-Borne Infection Testing and Diagnostic Laboratory Data: A Retrospective Cohort Study.

BACKGROUND AND AIMS: Although combination antiretroviral therapy has decreased morbidity and mortality in people living with HIV (PLWH), the prevalence of other sexually transmitted and blood-borne infections (STBBIs) is rising within this population. We used Latent Class Analysis to examine the diverse lab testing and diagnostic patterns of PLWH in British Columbia (BC), Canada to identify subpopulations of PLWH for targeted STBBI interventions.

METHODS

Our study population included all known PLWH with at least one STBBI lab test or diagnosis in BC between December 2003 and March 2020. Lab data were sourced from the BC Center for Excellence in HIV/AIDS Drug Treatment Program. We used Latent Class Analysis to group study participants based on lab testing and diagnostic data for gonorrhea, chlamydia, syphilis, hepatitis C virus (HCV), and hepatitis B virus (HBV). To compare the demographic compositions of each class, we used two-tailed logistic regression.

RESULTS

We assigned 9,328 study participants to one of four classes. The 2029 participants assigned to Class 1 (21.7% of our study population) tested for syphilis and HCV, with few diagnoses. Those in Class 2 (n = 2868; 30.7%) tested for HBV, HCV, and syphilis, with some being diagnosed with HCV and HBV. Class 3, the largest group (n = 3154; 33.8%), tested for all STBBIs but had few diagnoses. Finally, Class 4 (n = 1279; 13.7%) had higher testing and diagnoses for all STBBIs. Demographic composition varied significantly between classes; for example, participants in Class 4 had 7.42 times greater odds of being men who have sex with men compared to those in Class 1 (95% CI: 6.20-8.89).

CONCLUSIONS

We identified key subpopulations of PLWH based on STBBI testing and diagnosis. By taking a holistic approach and studying overall patterns in STBBI lab data, this work will help inform public health efforts and guide interventions targeting STBBIs.