Our findings indicate a high prevalence of hazardous alcohol consumption, and that illicit drug use is frequent among FSW and MSM and are associated with high-risk behaviors. Several studies indicates that alcohol consumption is highly prevalent among key population (5, 15–17). For FSW, hazardous drinking use may serve as a coping mechanism to deal the nature of their work (stress, violence, criminalization and stigmatization), while for MSM alcohol consumption may serve as a mechanism to deal with stigma and related stress (4, 17). These results emphasize the need for alcohol risk reduction programmes for key populations specifically focused on the adoption of safer drinking practices integrated into HIV prevention packages.
In our study hazardous drinking was more frequent among MSM with younger age. This likely mirrors social behavior related to alcohol use in the general population to enhance pleasure, to be more social, and/or life histories of traumatic experiences such as sexual orientation-based discrimination and childhood sexual abuse (18). Several studies demonstrate alcohol use in younger ages to be associated with a greater number of lifetime sexual partners, non-protected sexual intercourse, elevated levels of depressive symptoms, and alcohol abuse later in life (15, 18, 19). Within younger MSM, where there is an increased risk of acquiring HIV compared to their older counterparts, alcohol use preceding sex events represents a double risk for HIV and other STI (18, 20, 21) .
Unweighted pooled estimates conducted in our study demonstrate that FSW with hazardous alcohol consumption have an increased number of sexual partners, a higher occurrence of self-reported STI, higher perception of their HIV risk, and have higher HIV prevalence. Other studies demonstrate that hazardous alcohol consumption likely account for the positive association between frequency of drinking and increased number of clients (2). Alcohol affects decision-making about negotiating for safer sex, which can increase risk of HIV and other STI transmission. In addition hazardous heavy drinking and drug use have also been associated with poor adherence to antiretroviral therapy (ART) among HIV positive people and the interaction between all those substances usually leads to a higher susceptibility to co-morbidities and opportunistic infections (22).
Physical and sexual violence is recognized as a widespread public health problem and a violation of human rights. We found FSWs that use alcohol are enmeshed in a dynamic of physical and sexual violence victimization. A prior study conducted among FSW in the country found a high prevalence of physical and sexual violence, confirming the need for specific interventions to address this vulnerability (23).
The profile of FSW that use illicit drugs is consistent with what has been observed in other studies among KP in Mozambique, where drug use occurs more frequently in younger ages, individuals with higher number of sexual partners, and HIV and STI prevalence is higher among those that use drugs (10, 24). Several additional studies demonstrate that there is a strong relationship between substance use and unsafe sexual practices that increases the risk for HIV and STIs. FSW may also use substances as a way to numb the stigmatized experiences related to sexual practice and can also increase hazardous drinking.
Our study had some potential limitations. First, we measured the alcohol and drug use consumption by self-report; thus, the data might be under-reported due to social desirability bias. Second, due to missing data we were not able to assess the drug consumption among MSM. Third, like other cross-sectional surveys, we could not assess cause-and-effect relationships. Fourth, the FSW and MSM network assessed in the study may be missing important sub-groups (Eg. FSW and MSM with higher economic status). Finally, the analysis of pooled results from across the survey cities may affect social networks and chains could affect how representative sample was of the population. As a result, these findings need to be interpreted with caution and cannot be generalized to the entire MSM and FSW population in the survey cities or to KP nationally.