Cumulative inequality in social determinants of health in relation to depression symptom: an analysis of nationwide cross-sectional data from U.S. NHANES 2005-2018

Social determinants of health (SDoH) have been linked to a higher likelihood of experiencing mental health problems. This study aimed to investigate whether the accumulation of unfavorable SDoH is associated with depression symptom. Data was gathered from a representative population participating in the U.S. National Health and Nutrition Examination Survey spanning from 2005 to 2018. Self-reported SDoH were operationalized according to the criteria outlined in Healthy People 2030, with a cumulative measure of unfavorable SDoH calculated for analysis. The presence of depression symptom was identified using the Patient Health Questionnaire in a representative sample of 30,762 participants (49.2% males) representing 1,392 million non-institutionalized U.S. adults, with 2,675 (8.7%) participants showing depression symptom. Unfavorable SDoH were found to be significantly and independently associated with depression symptom. Individuals facing multiple unfavorable SDoHs were more likely to experience depression symptom (P for trend < 0.001). For instance, a positive association was observed in participants exposed to six or more unfavorable SDoHs with depression symptom (AOR = 3.537, 95% CI: 1.781, 7.075, P-value < 0.001). The findings emphasize that the likelihood of developing depression symptom significantly increases when multiple SDoHs are present, compared to just a single SDoH.