Prioritizing clinical utility to use allostatic load as a biomarker of the consequences of stress.

Abstract

Allostatic load measures the physiological consequences of stress and is associated with disease outcomes. Clinical use of allostatic load is limited, in part, because its calculation requires biomarkers not routinely measured in clinical care. Presently, we evaluated associations between high allostatic load and depression as co-occurring consequences of stress among a cohort representing population subgroups largely excluded from existing literature. We emphasize clinical implementation potential by employing both an established and a recent consensus streamlined allostatic load score. Data arise from a nested case-control study within the Southern Community Cohort Study (N = 982); 72% self-identified as Black, 61% reported income < $15,000. At baseline, participants completed surveys and provided blood samples analyzed for immune, metabolic, and cardiovascular biomarkers. Biomarkers exceeding clinical cutoffs were summed; counts above median indicated high allostatic load. Established and streamlined scores include 10 (albumin, C-reactive protein, estimated creatinine clearance, BMI, HbA1C, homocysteine, systolic and diastolic blood pressure, total cholesterol, triglycerides) and a subset of 5 biomarkers, respectively. Logistic regression models assessed cross-sectional associations between depression and allostatic load at study entry (odds ratios [OR], 95% confidence intervals [CI]). Established and streamlined scores demonstrated 88% agreement in identifying high allostatic load. Depression was associated with high allostatic load using both scores (established: OR: 1.37, 95%CI: 1.02-1.86; streamlined: OR: 1.39, 95%CI: 1.03-1.87). Associations remained in sex, race, and CRC-status stratified analyses. Robust associations were observed between depression, as a proxy measure of stress, with high allostatic load, supporting its validity as a clinically actionable biomarker of physiological and psychological dysregulation within an understudied population. Implementing the streamlined score may increase feasibility of allostatic load as a clinical indicator of stress.