Exercise attenuates the association between household pesticide exposure and depressive symptoms: Evidence from NHANES, 2005-2014

BACKGROUND: The effect of household pesticide exposure on depressive symptoms in the general population is underexplored, and the role of exercise in the association between pesticide exposure and depressive symptoms is unclear.

OBJECTIVE: The goals of this study are to examine whether the associations between household pesticide exposure and depressive symptoms exist in the general population, and whether exercise can attenuate these associations.

METHODS: We used data from the 2005-2014 National Health and Nutrition Examination Surveys (NHANES), including a total of 14708 US adult participants who were 20 years or older. Depressive symptoms were assessed using the Patient Health Questionnaire (PHQ-9). Exercise information on the recreational physical activity (RPA) and pesticide exposure were self-reported in an interview.

RESULTS: Participants with exposure of household pesticide had a higher odds ratio ([OR]; OR = 1.32, 95% confidence intervals [CI]: 1.12-1.56) for depressive symptoms, compared to those who had not been unexposed. A significant interaction between exercise and pesticide exposure on depressive symptoms was observed (P = 0.038). Stratified analysis showed that household pesticide exposure was associated with a 50% higher risk of depressive symptoms (OR = 1.50, 95% CI: 1.20-1.86) in the population with light RPA. However, we did not find a significant association in the group with moderate + vigorous RPA (P = 0.305).

CONCLUSION: This study further confirms that household pesticide exposure is associated with an elevated risk of depressive symptoms in the general population. More importantly, we for the first time reports that moderate + vigorous RPA attenuates the positive association between household pesticide exposure and depressive symptoms.