Gender matters? How does gender shape risk environment for syringe sharing among people who inject drugs in northern Mexico. Results from a cross-sectional survey

Introduction. HIV prevalence among people who inject drugs (PWID) is 5%. Studies have found a HIV prevalence around 10% among women who inject drugs (WWID) and 5% among men. Objective. To describe characteristics of risk environment that play different roles among men and women who inject drugs in Mexico that could be associated with those differentials. Method. In 2012 were interviewed in Hermosillo and Ciudad Juarez in places where population gathered. From them, 824 PWID 74.0% were men and 26.0% were women. Using chi-square test we analyzed associations of gender with demographics characteristics, drug use dynamics, and injecting behaviors. We fitted different generalized linear mixed models with random effects to test the hypothesis that predictors of receptive needle sharing have different effects on men and women. Results. Descriptive analysis showed that women live in conditions of higher vulnerability than men in terms of migration, educational attainment, occupation, and income. Women also reported a higher frequency of drug injection, a higher number of drugs used, and a higher prevalence of sharing needles. Variables significantly associated with the likelihood of sharing needles were: having being injected for someone else at first drug injection (adjusted odds ratio [AOR] = 1.60, 95% confidence interval CI [1.11, 2.25], p < .05); injecting once a day or more (AOR = 1.80, 95% CI [1.17, 2.70], p < .05), using alcohol or drugs at least half of the time at their sexual encounters (AOR = 1.64, 95% CI [1.16, 2.47], p < .05), experience of syringe confiscation by police (AOR = 1.54, 95% CI [1.13, 2.19], p < .05), and perceiving syringe availability as hard or very hard (AOR = 2.29, 95% CI [1.49, 3.32], p < .01). For women the most significant variable associated with syringe sharing was perception of syringe availability (AOR = 3.15, 95% CI [1.25, 7.91], p < .05), while for men was syringe confiscation by police (AOR = 1.74, 95% CI [1.20, 2.50], p < .05). Discussion and conclusion. Results suggests the need to design and implement harm reduction programs that tackle the specific need of WID. Enhancing syringe availability through permanent harm reduction programs, implemented in coordination between public health authorities and community-based organizations, is a basic action to stop HIV spreading among PWID in northern Mexico, along with the decriminalization policies towards these population.