Objective: To investigate whether time on antiretroviral treatment (ART) is associated with improvements in food security and nutritional status, and the extent to which associations are mediated by improved physical health status (PHS).

Design: The Uganda AIDS Rural Treatment Outcomes study (UARTO), a prospective cohort of HIV-infected adults newly initiating ART in Mbarara, Uganda.

Methods: Participants initiating ART underwent quarterly structured interview and blood draws. The primary explanatory variable was time on ART, constructed as a set of binary variables for each three-month period. Outcomes were food insecurity, nutritional status and PHS. We fit multiple regression models with cluster-correlated robust estimates of variance to account for within-person dependence of observations over time, and analyses were adjusted for clinical and socio-demographic characteristics.

Results: 228 ART-naive participants were followed for up to 3 years, and 41% were severely food insecure at baseline. The mean food insecurity score progressively declined (test for linear trend P<0.0001), beginning with the second quarter (b=-1.6; 95% CI, -2.7 to -0.45) and ending with the final quarter (b=-6.4; 95% CI, -10.3 to -2.5). PHS and nutritional status improved in a linear fashion over study follow-up (P<0.001). Inclusion of PHS in the regression model attenuated the relationship between ART duration and food security.

Conclusions: Among HIV-infected individuals in Uganda, food insecurity decreased and nutritional status and PHS improved over time after initiation of ART. Changes in food insecurity were partially explained by improvements in PHS. These data support early initiation of ART in resource-poor settings prior to decline in functional status to prevent worsening food insecurity and its detrimental effects on HIV treatment outcomes.