Antiretroviral treatment of adult Kenyans in this cohort resulted in significant and persistent clinical and immunological benefit. These findings document the viability and effectiveness of large-scale HIV treatment initiatives in resource-limited settings.

Cognitive impairment short of dementia affects nearly one in four community-dwelling elders and is a major risk factor for later development of dementia.

Depressive symptoms were frequent and often persistent in this patient population. We identified patterns of oscillating severity of symptoms within individuals but relatively stable incidence and prevalence rates over a 9-month period. Patients who exceeded the threshold on the CES-D at any time during the study had significantly greater health services use and poorer perceived health.

This is the first report of incidence rate differences for dementia and AD in studies of 2 populations from nonindustrialized and industrialized countries using identical methods and the same group of investigators in both sites. Further explorations of these population differences may identify potentially modifiable environmental or genetic factors to account for site differences in dementia and AD.