Changing association between schooling levels and HIV-1 infection over 11 years in a rural population cohort in south-west Uganda.

BACKGROUND: Previous studies have found that in Africa, a greater risk of HIV infection is often found in groups with higher educational attainment. However, some serial cross-sectional studies have found greater reductions in HIV prevalence among more educated groups, especially in cohorts of young adults. More recent studies have found some instances where higher schooling levels are associated with lower HIV prevalence. METHODS: We describe changes in the association between schooling levels, HIV prevalence and condom use in a rural population-based cohort between 1989/1990 and 1999/2000, in Masaka District, Uganda. RESULTS: In 1989-1990, higher educational attainment was associated with higher risk of HIV-1 infection, especially among males, but once odds ratios are adjusted for age, no significant relation between schooling and HIV infection remains. In 1999-2000, there is, for females aged 18-29 years, a significant relationship between higher educational attainment and lower HIV prevalence, even after adjustment for age, gender, marital status and wealth (P for trend 0.01). Tests for interaction, significant for males and both genders combined, show that more schooling has been shifting towards an association with less HIV infection between 1989-1990 and 1999-2000, especially for young individuals. Condom use increased during the study period and this increase has been concentrated among more educated individuals. CONCLUSIONS: These findings suggest that over a decade more educated young adults, especially females, have become more likely to respond to HIV/AIDS information and prevention campaigns by effectively reducing their sexual risk behaviour.