Shared genetic factors in the co-occurrence of symptoms of depression and cardiovascular risk factors

BackgroundWe aim to investigate the extent to which shared genetic and shared environmental factors play a role in the co-occurrence of symptoms of depression and cardiovascular risk factors.MethodsThe analyses included 2383 individuals from a genetically isolated population in the Netherlands (mean age 48.7 years (standard deviation 15.1), percentage of women 56.9%). Symptoms of depression were assessed using the Center for Epidemiology Studies Depression Scale (CES-D) and the Depression subscale of the Hospital Anxiety and Depression Scale (HADS-D). Assessment of cardiovascular risk factors included systolic and diastolic blood pressure, plasma, glucose levels, high and low density lipoprotein (HDL, LDL) and total cholesterol levels.ResultsOverall, we found that HADS-D was significantly correlated to total cholesterol levels (correlation coefficient [ρ] = 0.05), and inversely associated to HDL (ρ = − 0.06). Statistically significant genetic correlations (ρG) were found between CES-D scores and total plasma cholesterol (ρG = 0.30), LDL (ρG = 0.31) and total cholesterol/HDL ratios (ρG = 0.25). For HADS-D scores, a significant genetic correlation was found with total cholesterol/HDL ratios (ρG = 0.27). Environmental correlations (ρE) with an opposite direction were found between CES-D and both total cholesterol (ρE = − 0.16) and LDL (ρE = − 0.15).LimitationBy adjusting for sibship, we are taking into account environmental effects, however we cannot exclude dominance variance.ConclusionsOur study shows that there is evidence for shared genetic factors contributing to the co-occurrence of symptoms of depression and lipid levels. This finding suggests a joint genetic pathogenesis. Future research is encouraged to assess susceptibility genes for mood disorders to be studied for cardiovascular disorders and vice versa.