Alcohol availability and prevalent Chlamydia trachomatis in young Australians: a multi-level analysis

Background Prevalence of sexually transmissible infections (STIs) has been associated with availability of alcohol. This paper investigates potential associations between prevalent cases of chlamydia in young people in Australia and the availability of alcohol within their local area, defined as postcode of residence. Methods Alcohol availability was determined at the postcode level using liquor licensing data, classified as total number of licences, number of 'take-away' licences and number of licenses by population. Participant data were drawn from a survey targeting Australians aged 16-29years in rural and regional Australia, capturing demographic details including postcode of residence, indicators of sexual behaviour including condom use and chlamydia test results. Mixed-effects logistic regression was used to examine potential associations between first, alcohol availability and chlamydia, and second, between condom use and chlamydia. Results We found little evidence of associations between alcohol availability and chlamydia in either unadjusted or adjusted models. After adjusting for alcohol availability, we observed significant associations between inconsistent condom use and chlamydia prevalence, whether alcohol availability was measured as total number (adjusted odds ratio (AOR) 2.20; 95% confidence interval (CI) 1.20, 3.70), number of take-away licenses (AOR 2.19; 95% CI1.30, 3.69) or licenses per 1000 population (AOR 2.19; 95% CI 1.30, 3.68). Conclusion Little evidence of association between alcohol availability and chlamydia at the postcode level was found. Further research is required to determine appropriate measures of 'local area' and how characteristics thereof may impact on sexual health.