Background: This study investigated the structural-environmental and individual-level social factors associated with the numbers of commercial sex clients of female sex workers (FSWs) per month (CPM).
Methods: Data were analyzed from cross-sectional surveys of FSWs in 5 districts in Karnataka state, India (2004-2005). Bivariate and multivariable negative binomial regression models with generalized estimating equations were constructed for each district. Normalized weights were used to account for complex sampling design.
Results: Median (average) CPM varied significantly (P < 0.001) across districts, from 40.0 (56.9) CPM in the district with the highest immunodeficiency virus prevalence (33.9%) to 16.0 (26.1) in the district with the lowest prevalence (9.7%). In multivariable analysis, there was a significant positive association between rates of CPM and sex work as sole income in 4 districts (adjusted incidence rate ratios, AIRR: [95% confidence intervals]: AIRR: 1.3 [1.0-1.7], P < 0.005-1.7 [1.2-2.5], P < 0.01); age, typology (place of solicitation), and marital status were significantly associated with CPM in 3 districts, with an inverse association between age and CPM (P < 0.01). FSWs soliciting clients in brothels had higher rates of CPM than home-based FSWs in 2 districts (AIRR: 1.5 [1.1-2.0]-1.6 [1.0-2.7], P < 0.05), whereas public places-based FSWs had higher rates in 1 district (AIRR: 1.4 [1.1-1.8], P < 0.01); cohabiting FSWs had higher rates than married FSWs in 3 districts, whereas single FSWs had higher rates in one district.
Conclusions: These results provide support for the continued development of structural core group interventions that address common elements of sex work placing FSWs at higher risk for immunodeficiency virus, as well as geographically focused programs that account for local differences in sexual structure.