Interaction between depression and non-essential heavy metals (Cd, Pb, and Hg) on metabolic diseases

Metal exposure and depression have each been associated with adverse metabolic diseases, but no study has examined the potential interaction between them. We examined the interaction of depression on the association between metals and metabolic diseases among adults.

The interaction of depression in the relationship between metal and metabolic disease in adults was investigated using NHANES, a cross-sectional survey design.

By employing data from the NHANES database spanning the years 2007-2018, regression models were employed to investigate the independent impacts of heavy metals (cadmium, lead, and mercury) and depression on metabolic diseases (type 2 diabetes, hypertension, hyperlipidemia, metabolic syndrome). Subsequently, the association between metals and metabolic diseases was explored stratified by depression, and the interaction between heavy metals and depression was explored. Because of the complex NHANES design, statistical evaluations were adjusted through weighting to represent the populace of the United States.

We found log transformed-urinary lead was significantly associated with type 2 diabetes (OR: 2.33; 95 % CI: 1.23, 4.41) in adults with depression. Log transformed-urinary lead was not associated with type 2 diabetes (OR: 0.84; 95 % CI: 0.56, 1.27) in adults without depression. The interaction between Pb and depression in type 2 diabetes was significant (P for interaction = 0.033). Log transformed-urinary lead * depression was significantly associated with type 2 diabetes (OR: 1.82; 95 % CI: 1.01, 3.34) in adults. There was no significant interaction between cadmium and mercury exposure and depression in patients with type 2 diabetes, hypertension, hyperlipidemia, and metabolic syndrome (P for interaction > 0.05).

The presence of depression positively modified the adverse associations between urinary lead and type 2 diabetes.