Predictors and impact of losses to follow-up in an HIV-1 perinatal transmission cohort in Malawi.

ABSTRACT

PIP: Predictors and the impact of losses to follow-up of infants born to a large HIV- infected cohort of delivering women in urban Malawi were studied. The women enrolled in an intervention trial including vaginal cleansing with chlorhexidine at the time of delivery. Findings showed that of the 2156 infants born to HIV- infected mothers, about 1359 (63.1%) had been diagnosed with HIV infection, 797 (36.9%) with undetermined status, 144 (6.7%) with missing status, and about 653 (30.3%) were never brought back for follow-up. The odds of HIV positivity decreased in the determination of infectious status (P = 0.03) despite the probability of additional transmission from breast-feeding. Late-coming and lost children of less educated parents had similar birth weight (P = 0.50) and were likely less to return. This was probably due to the fact that the fathers of the lost children were farmers. Besides, infant birth weight, twins vs. singletons, and maternal education were affiliated with significant variation in the observed risk of perinatal transmission among HIV-positive infants. Thus, with regard to the intervention trial, the LFU were approximately equal in both groups. There was no evidence that the losses were unbalanced between arms in relation to the predictors of transmission.