The association between allostatic load and cognitive function: A systematic and meta-analytic review

Previous research suggests that high allostatic load (AL), a biological indicator of physiological dysregulation due to chronic stress, is associated with poor cognitive functioning. To date, no studies have systematically reviewed the literature to evaluate the strength and consistency of this relationship. The objective of this study was to conduct a systematic and meta-analytic review of studies that have investigated the association between AL and performance on standardized cognitive tests among adults aged 18 years and older. A total of 18 studies were retained for review. Meta-analyses revealed a significant cross-sectional association between higher AL and poor global cognition (r = -0.08, p <  0.001) and executive function (r = -0.07, p =  0.02), but not memory (r = -0.07, p =  0.10). Due to variation in statistical methods used, longitudinal meta-analyses were not performed. Qualitative review of the literature suggests that AL algorithm, physiological systems and individual biomarkers included in the AL index, and sample age may be key moderators of the AL-cognition relationship. Although the magnitude of reported associations is small, findings support AL as a robust indicator of cognitive function among adults. Study limitations and future directions are discussed.