The specific relationship among depression, obesity, and wet-overactive bladder (wet-OAB) lacked comprehensiveness.

This cross-sectional study included 23,154 participants from the 2005–2020 National Health and Nutrition Examination Survey (NHANES). The study outcome was wet-OAB risk. depression levels were the primary exposure and graded to none (0–4), low (5–9), moderate (10–14), and severe (≥ 15) using the Patient Health Questionnaire-9. General and abdominal obesity were assessed based on body mass index (BMI) and waist circumference (WC), respectively. The logistic regression and restricted cubic spline (RCS) analysis were applied to probe their association based on complex multistage sampling designs. Mediation effect analysis was constructed to address the mediating role of obesity.

In fully adjusted models, a positive association was suggested between wet-OAB and depression levels with OR(95 %CI) of 2.34(1.98–2.75) in mild, 2.66(2.13–3.31) in moderate, and 3.14(2.34–4.20) in severe depression. General and abdominal obesity were significantly associated with increasing depression levels and wet-OAB risk (P for trend < 0.001). RCS analyses showed Log-shaped non-linear associations between depression levels and wet-OAB, especially in overweight, obesity subgroups, and abdominal obesity. General obesity with BMI and abdominal obesity with WC performed respectively a partially mediated proportion of 5.16 % and 4.25 % between depression levels and wet-OAB (P for indirect effect < 0.001).

Individuals with elevated depression levels tend to have a higher risk of wet-OAB, especially in obesity. General and abdominal obesity are important partial mediators in the effects of depression levels on wet-OAB. Patients with wet-OAB need to pay attention to mental health interventions and weight control.