Association between perfluorinated alkyl substances and depression

Background Perfluorinated alkyl substances (PFAS) are a class of synthetic organic fluorides, which have adverse health effects on brain function, and limited research has been conducted on their effects on depression.

Objective To assess potential correlation between serum PFAS and depression.

Methods Using the 2015—2016 and 2017—2018 National Health and Nutrition Examination Survey (NHANES) datasets, 2626 subjects with complete relevant information in people ≥20 years old were selected. Logistic regression and restricted cubic splines were used to analyze the association and dose-response relationship between serum PFAS concentration and depression. Subgroup analysis was performed on sex, age, race, education level, marital status, family income to poverty ratio, moderate exercise, body mass index, and drinking status.

Results Among the 2626 subjects, there were 666 patients (25.4%) with mild or above depression. After adjusting for race, education level, marital status, body mass index, moderate exercise, drinking history, cotinine, and other types of PFAS, serum perfluorooctane sulfonate (PFOS) was positively associated with the risk of depression (OR=1.85, 95%CI: 1.14, 3.02), and showed a nonlinear dose-response relationship (χ²=6.37, P_nonlinear=0.012). Perfluorononanoic acid (PFNA) was inversely associated with the risk of depression (OR=0.23, 95%CI: 0.14, 0.39), and showed a linear dose-response relationship (P_trend<0.001, χ²=35.13, P_overall<0.001). After subgroup analysis, it was found that males, 20-39 year-olds and 40-64 year-olds were more sensitive to PFNA exposure (OR=0.15, 95%CI: 0.06, 0.37; OR=0.16, 95%CI: 0.06, 0.40; OR=0.18, 95%CI: 0.08, 0.39). PFOS only showed a statistically significant health effect in people aged 20-39 years (OR=3.00, 95%CI: 1.14, 7.94). In addition, among subgroups of non-Hispanic blacks, cohabitants, current drinkers, high school graduates, and obese patients, exposure to PFAS was significantly associated with the risk of depression.

Conclusion PFOS exposure may be associated with increased levels of depression, whereas PFNA exposure may be protective.