HIV, TB Co-Infection Associated With Decreased Neurological Performance


Co-infection of human immunodeficiency virus (HIV) and tuberculosis (TB) may be associated with decreased neurological and neuropsychological functioning, according to a study published in Clinical Infectious Diseases.
In the study, researchers developed a cohort of 860 individuals who were HIV+ and were a subset of the AIDS Clinical Trial Group (ACTG) A5175 (a randomized antiretroviral therapy [ART] trial with HIV+) from Brazil, India, Malawi, Peru, South Africa, Thailand, and Zimbabwe. Of the participants, 47 individuals had active TB, 36 had pulmonary TB, 9 had extrapulmonary (non-CNS) TB, 1 had features of both, and 1 had central nervous system (CNS) TB alone.

Standardized neurological and brief neuropsychological examinations were obtained from participants every 6 months. These exams entailed timed gait, semantic verbal fluency, and finger tapping. Neurological exams included neurological history, symptom review, and cognitive, motor, sensory, and reflex assessments. Generalized estimating equation models evaluated the relationship between TB and neurological and neuropsychological performance.
Participants with TB co-infection had significantly poorer performance on Grooved Pegboard (a manipulative dexterity test) (P <.001) and finger-tapping with the non-dominant hand (P <.01). TB was associated with diffuse CNS disease (P <0.05). Further, among individuals with TB, odds of reporting a decreased quality of life were 9.27 times (P <.001) higher and odds of productivity loss were 8.02 times (P =.0005) higher. Neuropsychological test scores did improve (P <.05) after the initiation of ART, with the exception of semantic verbal fluency, and were maintained throughout the 3-year study. No differences in neurological and neuropsychological functioning between treatment regimens were detected (P >.10).

Researchers concluded that « co-infection of HIV and TB was associated with poorer neurological and neuropsychological functioning despite overall neurological improvement with successful antiretroviral therapy. » They emphasized, however, that improvements after the administration of ART therapy were encouraging.

This study was supported by The National Institute of Mental Health and the AIDS Clinical Trials Group, funded by The National Institute of Allergy and Infectious Diseases and Statistical and Data Analysis Center.