Abstract
Background There is an existing link between two of the most common diseases, obesity and depression. These are both of great public health concern, but little is known about the relationships between the subtypes of these conditions. We hypothesized that non-melancholic depressive symptoms have a stronger relationship with both body composition (lean mass and fat mass) and dysfunctional glucose metabolism than melancholic depression. Methods For this cross-sectional study 1 510 participants from the Helsinki Birth Cohort Study had their body composition evaluated as lean mass and fat mass (Lean Mass Index + Fat Mass Index = Body Mass Index). Participants were evaluated for depressive symptoms utilizing the Beck Depression Inventory, and had laboratory assessments including an oral glucose tolerance test. Results Higher than average Fat Mass Index (kg/m2) was associated with a higher percentage of participants scoring in the depressive range of the Beck Depression Inventory (p=0.048). Higher Fat Mass Index was associated with a higher likelihood of having depressive symptoms (OR per 1-SD Fat Mass Index=1.37, 95% CI: 1.13-1.65), whereas higher Lean Mass Index (kg/m2) was associated with a lower likelihood of having depressive symptoms (OR per 1-SD Lean Mass Index=0.76, 95% CI: 0.64-0.91). Participants with an above average Fat Mass Index more frequently had non-melancholic depressive symptoms (p=0.008) regardless of Lean Mass Index levels (p=0.38). There was no difference between the body composition groups in the likelihood of having melancholic depressive symptoms (Fat Mass Index p=0.83, Lean Mass Index p=0.93). The non-melancholic group had higher Fat Mass Index than either of the other groups (p<0.001), and a higher 2-hour glucose concentration than the non-depressed group (p=0.005). Conclusion As hypothesized, non-melancholic depressive symptoms are most closely related to high fat mass index and dysfunctional glucose metabolism.
Changes in testosterone related to body composition in late midlife: Findings from the 1946 British birth cohort study