Research indicates that older people living with HIV (PLWHIV) have overall poorer health outcomes than people of a similar age without HIV. Allostatic load (AL) markers can be used as indicators of the wear and tear of stress on biological systems that could help PLWHIV and their physicians plan care, explains Pariya L. Fazeli Wheeler, PhD. However, data are limited on AL markers in PLWHIV.
Dr. Wheeler and colleagues conducted a study, published in the Journal of Acquired Immune Deficiency Syndromes, to examine the potential risks of high AL and its relationship with outcomes in older PLWHIV. Participants completed a neurobehavioral assessment and provided a blood sample for calculating AL. AL was combined creating a sum of markers in the highest risk group for 12 categories: cortisol, DHEA, IL-6, TNF-alpha, C-reactive protein, glucose, total cholesterol, high-density lipoprotein cholesterol, triglycerides, albumin, systolic and diastolic blood pressure, and BMI. A sample of seronegative controls also had available data for the blood AL markers. PLWHIV were found to have higher risk levels than seronegative controls for several of the individual AL markers. Additionally, the study team found that higher AL was associated with lower psychological resilience, less physical activity, poorer neurocognitive functioning, greater basic activity of daily living complaints, and diabetes among African Americans with HIV. Dr. Wheeler believes the increased impact on African Americans with HIV represents a potential intervention target to buffer negative effects of stress and AL on outcomes in this population that is overrepresented in the HIV epidemic, yet underrepresented in this type of research.
“Our study confirms what other studies have found; the whole of AL seems to be greater than the sum of its parts,” notes Dr. Wheeler. “Therefore, calculating an AL composite is both useful in a research context and possibly useful in future clinical settings to predict risk for poor functioning and outcomes, such as morbidity and mortality.”
Dr. Wheeler believes longitudinal studies with diverse samples of older PLWHIV are needed to expand upon the study findings. “This was a first step,” she explains. “Understanding the temporal associations of risk and protective factors of AL, as well as the association of AL with future health trajectories is important, with the ultimate goals of predicting and preventing disease and mortality.”