Elevated depressive symptoms and compositional changes in LDL particles in middle-aged men
Lehto, S.M., A. Ruusunen, L. Niskanen, T. Tolmunen, S. Voutilainen, H. Viinamaki, George A. Kaplan, and J. Kauhanen. 2010. "Elevated depressive symptoms and compositional changes in LDL particles in middle-aged men." European Journal of Epidemiology, 25(6): 403-409.
Depression and cardiovascular disease (CVD) are closely associated, but the mechanisms underlying this connection are unclear. Regardless of the low cholesterol levels observed in depression, a small particle size of low-density lipoproteins (LDL), as well as elevated apolipoprotein B (ApoB) levels, are related to increased CVD risk, even when levels of LDL cholesterol are low. We examined the association between elevated depressive symptoms and compositional changes in serum LDL particles in a sample of 2,456 middle-aged Finnish men. Depressive symptoms were assessed with the 18-item Human Population Laboratory Depression Scale, and the study population was divided into two groups (elevated depressive symptoms, n = 269; non-depressed, n = 2,187). The levels of serum total cholesterol (TC), low- and high-density lipoprotein cholesterol (LDL-C, HDL-C), triglycerides (TG), and ApoB were determined. The LDL-C/ApoB ratio, a marker of compositional changes in LDL particle size, was calculated. The group with elevated depressive symptoms had lowered levels of serum TC (P = 0.028) and LDL-C (P = 0.008). No differences were observed in the LDL-C/ApoB ratio. The likelihood for belonging to the group with elevated depressive symptoms increased 10% for each 0.5 mmol/l decrease in the levels of TC (P = 0.002) or LDL-C (P = 0.001) in regression models adjusted for age, examination years, marital and socioeconomic status, energy expenditure, body mass index, CVD history, alcohol consumption, smoking, and the use of lipid-lowering, antidepressant and antipsychotic medications. Our findings suggest that greater small-particle LDL levels are not associated with depression, and are thus unlikely to underlie the association between cardiovascular risk and depression.
Country of focus: Finland.