Allostatic Load and Depression Symptoms in Cancer Survivors: A National Health and Nutrition Examination Survey Study

Background: Individuals with cancer often experience stress throughout the cancer trajectory and have a high risk of experiencing depression. Objective: The aim of this study was to examine the relationship between allostatic load (AL), a measure of cumulative stress-related physiologic dysregulation of different body systems, and symptoms of depression in cancer survivors. Methods: Participants were 294 adult cancer survivors from the US National Health and Nutrition Examination Survey (NHANES 2007-2018). Allostatic load was measured using 14 indicators representing cardiometabolic risk, glucose metabolism, cardiopulmonary functioning, parasympathetic functioning, and inflammation. Depressive symptoms were measured with the Patient Health Questionnaire-9. The relationship between AL and depressive symptoms was investigated using multiple regression adjusted for diverse sociodemographic and diagnosis variables. Results: Higher AL was associated with higher depressive symptom scores. The higher risk of depression was concentrated among those survivors in the highest AL quartile, with 21% (95% confidence interval, 11%-32%) of survivors presenting a high risk of depression compared with 8% to 11% of survivors in the lower quartiles. In exploratory analyses, the relationship between AL and depressive symptoms was only significant among survivors with a lower income. In contrast, in survivors in the highest income group, depressive symptoms were lower and unrelated to AL. Conclusion: High AL is associated with more depressive symptoms among cancer survivors.