Most HIV research in Sub-Saharan Africa (SSA) ignores persons aged 50 years and above, though a few studies have reported a high HIV prevalence among older people. This study aimed to estimate socio-demographic inequalities in HIV testing behaviour and HIV prevalence among adults aged 50+ years, living in Ifakara town, Tanzania. This cross-sectional study used data from the baseline measurement of the Ifakara MZIMA cohort study in 2012/13. Consenting participants were interviewed and tested for HIV. Associations between HIV testing behaviour and HIV prevalence with socio-demographic indicators were explored with multivariable logistic regression. Among the 1643 adults 50+ years included in the study, HIV prevalence and the HIV testing rate (ever tested) were 6% and 11.4% respectively. The HIV testing rate was lower for older people (aOR = 0.19 (95% CI 0.09-0.41 for 75+ versus 50-54 years); higher for those separated/divorced/widowed than those married (aOR = 1.46; 1.02-2.10); higher for "other Christians" than Muslims (aOR = 1.95; 1.06-3.58); and higher for primary (aOR = 1.54; 1.01-2.33) and secondary (aOR = 3.47; 2.11-5.70) school graduates than those without education. HIV prevalence was lower for older people (aOR = 0.27; 0.11-0.66 for 75+ versus 50-54); and for Catholics compared to Muslims (aOR = 0.54; 0.34-0.85). The high HIV prevalence among older adults and the low HIV testing behaviour call for more efforts on HIV prevention, treatment and care.
Keywords: HIV; older adults; prevalence; socio-economic inequalities; testing.