Researchers said they found no evidence that HIV accelerates aging-related brain changes over a 2-year period in middle-aged patients on successful ART.
“This provides reassurance that, with virological suppression, [people living with HIV (PLWH)] in middle age are not at increased risk of progressive cognitive decline and abnormal deterioration to brain health over 2 years,” James H. Cole, PhD, honorary research fellow in the division of brain sciences at Imperial College London and department of neuroimaging, Institute of Psychiatry, Psychology and Neuroscience at King’s College London, and colleagues wrote in Clinical Infectious Diseases.
Although combination ART (cART) has substantially reduced AIDS-related morbidity and mortality, PLWH continue to experience higher rates of neurological, cardiovascular, renal, hepatic and pulmonary disease, as well as cancer, osteoporosis and physical frailty. Because these conditions typically increase with age, there is concern that age-related deterioration may accelerate in PLWH, despite cART, according to the researchers.
Few longitudinal neuroimaging studies have investigated accelerated brain changes and cognitive decline in PLWH. Some have demonstrated accelerated brain pathology; however, Cole and colleagues noted that these studies have important limitations. Therefore, the researchers conducted a multicenter, longitudinal study involving 134 virologically suppressed PLWH (median age, 56 years) and 79 demographically matched HIV-negative controls (median age, 57.2 years) to clarify whether PLWH on cART have increased changes in age-related neuroimaging measures.
All study participants completed neuropsychological assessments and underwent multimodality neuroimaging during a baseline and 2-year follow-up visit. The researchers hypothesized that MRI measures would be abnormal among PLWH at baseline; that PLWH would have greater rates of change in MRI metrics vs. HIV-negative controls over 2 years; and changes in MRI metrics would be associated with a decline in cognitive function, despite cART.
At baseline, the researchers reported that PLWH had inferior global cognitive performance (P < .01), lower gray matter volume (P = .04), higher white matter hyperintensity load (P = .02), abnormal white matter microstructure (P < .005) and greater “brain-predicted age difference” (P = .01). Over the 2-year follow-up period, neuroimaging measures showed that both PLWH and controls experienced similar reductions in brain volumes, altered white matter structure, increased white matter hyperintensity load and reduced cerebral perfusion. The researchers also observed similar changes in neuropsychological tests between the groups. Cognitive performance, they reported, remained stable over time.
“Our results indicate that in PLWH on suppressive cART, any progressive changes to the brain that occur are no greater than those seen in appropriately matched HIV-negative controls,” the researchers concluded. “To better understand trajectories of cognitive aging in PLWH, future studies would benefit from larger numbers, more frequent assessments and run-in periods to mitigate practice effects.” – by Stephanie Viguers
Disclosure: One author reports receiving grants, personal fees and research grants from Bristol-Myers Squibb, Gilead Sciences, Janssen, Merck and ViiV Healthcare, but not directly related to the study.