Insulin resistance and depressive symptoms in young adult males: findings from Finnish military conscripts.

OBJECTIVE: To investigate whether the association between insulin resistance (IR) and depressive symptoms is present already in young adult males. The association between IR and depression has been poorly studied, although the existence of a connection of Type II diabetes with depression is well established. We previously demonstrated at epidemiological level in two groups of men aged 31 years and 61 to 63 years that IR is linked with depressive symptoms.

METHODS: In a cross-sectional study, involving 1054 healthy Finnish male military conscripts of about 19 years of age, IR was defined through homeostasis model assessment (HOMA-IR). The severity of the depressive symptoms was evaluated through a Finnish modification of the 13-item Beck Depression Inventory (R-BDI). Moderate-to-severe depressive symptoms were said to be present, if the R-BDI score was > or = 8, and mild depressive symptoms were present if the R-BDI score was 5 to 7.

RESULTS: After adjusting for confounders, moderate-to-severe depressive symptoms increased the risk for IR, as defined by the highest decile of the HOMA-IR, up to 2.8-fold (odds ratio = 2.8; 1.2-6.5). Mild depressive symptoms were not significantly associated with IR.

CONCLUSIONS: In young adult males, co-occurring strictly defined IR seems to be positively associated with current moderate-to-severe depressive symptoms.