This systematic review aimed to quantify the prevalence of substance use among female sex workers (FSWs) in low- and middle-income countries (LMICs).

Design: The review protocol was registered with PROSPERO (CRD42021242048). We searched Ovid, PubMed and Web of Science databases for peer-reviewed, quantitative studies from inception to 6th March 2023. Study designs included: cross-sectional, case–control, cohort study, case series analysis, or experimental studies. Study quality was assessed using the Centre for Evidence-Based Management (CEBM) Critical Appraisal Tool.

Setting: FSWs in LMICs.

Participants/Inclusion criteria: any measure of prevalence or incidence of substance use (not alcohol or tobacco) among FSWs aged 18+ years.

Measurements: A narrative synthesis was conducted across all studies meeting the inclusion criteria. Pooled prevalence estimates for ‘ever’ and ‘recent’ drug use were calculated using a random effects model.

3135 papers were identified; 161 papers reporting on 102 studies with 167,333 FSWs from 39 LMICs met the inclusion criteria. 26 studies scored high, 61 scored moderate, and 15 scored in the lower quality range. Only 4/102 studies used a validated measurement tool to assess levels of substance use dependence. The mean age of study participants was 28.9 years (SD 7.7). The pooled prevalence for recent (past month to past year) substance use among FSWs in LMICs is: illicit drug use 29% (95% CI: 14–34%), cannabis 20% (95% CI: 8–30%), cocaine 21% (95% CI: 9–32%), amphetamine type stimulants 19% (95% CI: 12–26%), opioids 8% (95% CI: 4–12%), sedatives and sleeping pills 6% (95% CI: 0–12%), inhalants 4% (95% CI: –4–12%), hallucinogens 0% (95% CI: 0–0%), and recent drug use during sex work 42% (95% CI: 15%–68%). Only 5/102 studies reported a substance use intervention. Key study limitations include the lack of a validated measurement tool by most studies (96%) meaning it was not possible to distinguish between any drug use vs. harmful drug use. The criminalisation of drug use may have led to under-reporting and an underestimate of true substance use prevalences.

FSWs in LMICs report a high prevalence of recent drug use – including during sex work – with cannabis, cocaine and amphetamine type stimulants the most commonly used. There is an urgent need for effective low-cost substance use interventions. Future studies should use validated substance-use measurement tools to assess the burden of substance use disorders.

Due to its widespread use in the sex work industry, female sex workers (FSWs) in low- and middle-income countries (LMICs) are at high risk of harmful alcohol use and associated adverse health outcomes. This systematic review and meta-analysis aims to provide an estimate of the prevalence of harmful alcohol use among FSWs in LMICs and to examine associations with common health and social concerns.

The review protocol was registered with PROSPERO, number CRD42021237438. We searched three electronic databases for peer-reviewed, quantitative studies from inception to 24th February 2021.

Inclusion criteria:

• • Any measure of prevalence or incidence of alcohol use among FSWs aged 18 years or older.

• • Countries defined as LMIC in accordance with the World Bank income groups 2019.

• • Study designs: cross-sectional survey, case–control study, cohort study, case series analysis, or experimental study with baseline measures for alcohol use.

Pooled prevalence estimates were calculated for:

1. 1. Any hazardous/harmful/dependent alcohol use

2. 2. Harmful/dependent alcohol use only, both overall and by region

3. 3. Daily alcohol use.

4. 4. Meta-analyses examined associations between harmful alcohol use and violence, condom use, HIV/STIs, mental health problems and other drug use.

In total, 435 papers were identified. After screening, 99 papers reporting on 87 unique studies with 51,904 participants from 32 LMICs met the inclusion criteria. Study designs included cross-sectional (n = 89), cohort (n = 6) and experimental (n = 4). Overall, 5 scored as high quality, 79 studies scored as moderate and 15 scored as weak quality. Twenty-nine papers reporting on 22 unique studies used validated alcohol use tools including AUDIT, CAGE and WHO CIDI. The pooled prevalence of any hazardous/harmful/dependent alcohol use was 41% (95% CI: 31–51%), and of daily alcohol use was 26% (95% CI: 17–36%). There was variation in harmful alcohol use by global region (Sub-Saharan Africa: 38%; South Asia/Central Asia/ East Asia and Pacific: 47% and Latin America and the Caribbean:44%). Harmful alcohol use was significantly associated with inconsistent condom use (pooled unadjusted RR: 1.65; 95% CI: 1.01–2.67), STIs (pooled unadjusted OR: 1.29; 95% CI 1.15–1.46); and other drug use (pooled unadjusted OR of 2.44; 95% CI 1.24–4.80), but not with HIV, violence or mental health problems.

We found a high burden of problem alcohol use and daily alcohol use among FSWs in LMICs. Harmful drinking was associated with HIV risk factors such as inconsistent condom use, STIs and other drug use. There is an urgent need for tailored interventions for FSWs in LMICs that address alcohol use as well as the associated sex work risk environment