Evidence-based perspectives on the implementation of screening for neurocognitive impairment in HIV

Abstract

This review considers the justification, accuracy, limitations, and potential applications of screening instruments for neurocognitive impairment (NCI) in HIV-positive patients. Wilson and Jungner's classic screening principles provide thinking tools to guide discussion: the condition should be an important health problem; there should be an accepted treatment; there should be a suitable test; and the natural history of the condition should be adequately understood. NCI appears to be common among HIV-positive patients, but evidence of its progression in those established on suppressive antiretroviral therapy is inconclusive. Also, there are limited data on the optimum management in patients who are found to have NCI but are already receiving effective antiretroviral therapy. The accuracy of screening tests, such as the HIV Dementia Scale and the Montreal Cognitive Assessment, is such that their positive and negative likelihood ratios are close to 1; therefore, many false positive and negative results will arise when using these tests in most clinical scenarios. We argue that the place for screening for neurocognitive impairment is within a management pathway that aims to identify a range of psychological and neurological problems. Widespread implementation of screening for HIVassociated neurocognitive disorders is premature, on the basis of available evidence.