Intellectual quotient score comparison between HIV-infected and HIV exposed children at the Peruvian National Institute of Child Health, Lima Peru

Abstract

Objectives: Pediatric HIV (human immunodeficiency virus) encephalopathy includes motor and cognitive deficits and can result in poor school performance, borderline intelligence or mental retardation. We compared intellectual quotient (IQ) in HIV-infected and -uninfected children in Peru and examined the relationship between verbal and executive function with clinical stage of HIV infection (CDC classification), HIV viral load, CD4 cell count and other potential risk factors. Methods: We evaluated 28 HIV-infected children and 28 HIVuninfected children matched for age and gender. The majority of HIV-uninfected children were exposed to HIV during pregnancy but did not become infected. Neuropsychologic testing included the Wechsler-Revised (WPPSI-R) for children between 3 - 7 years and 3 months, and the Wechsler Third Edition (WISC-III) for children older than 7 years and 4 months. Clinical records were reviewed to obtain medical history, clinical and demographic data. T-test and Pearson's correlation (R) were used to compare groups. IQ score was categorized as average or above (score>90), low average (score 80-89), or borderline intellectual function or below (score<80). Results: The average IQ score among HIV-infected children was lower than in HIV-uninfected children (84.6 vs. 91.7, p =0.05). This difference was driven by the verbal sub test (81.2 vs. 90.3, p =0.05). The percentage of children with an average IQ score or higher was greater in the HIV-uninfected than -infected group (57.1 % vs. 32.1 %, resp.) (32.1 %); and more HIV-infected children scored in the borderline intellectual function or below range (35.7 % vs. 17.9 %, resp.); these differences were not statistically significant. Children with advanced HIV infection (CD4 cell count < 100 cells/ll) had lower IQ scores and verbal performance than children with less-advanced HIV infection, but these differences were not statistically significant. Verbal test scores were negatively correlated with HIV viral load (R=- 0.424, p=0.024). Conclusions: HIV infection was associated with lower IQ scores in Peruvian children. The comparison group of HIV-uninfected children, who were exposed to HIV in uterus, strengthened our ability to exclude many potential confounding demographic and socioeconomic factors. The associations between lower cognitive functioning and advanced HIV infection are not surprising, but emphasize the need for cognitive therapies for HIV-infected children in developing countries.