Associations between serum lipid levels and suicidal ideation among Korean older people

There have been inconsistent reports on the relationships between lipids and suicidality, and studies conducted in older adults are rare. This study examined associations between serum lipid levels and suicidal ideation in an older population.

This study used data obtained from a representative Korean sample of 4265 people age 65 years or older who completed a self-administered questionnaire about suicidal ideation over the last year. The fasting serum concentrations of total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides were measured and categorized into lower, intermediate (reference), and upper quartiles. A complex sample logistic regression stratified by gender was performed to determine the associations between serum lipid levels and suicidal ideation after controlling for covariates including age, education, marital status, current smoking, alcohol drinking, body mass index, hypertension, diabetes, diagnosed depression, antidepressant use, and lipid-lowering therapies.

In this study, the prevalence of suicidal ideation in an older Korean population was 22.9% (SE=0.9%). The prevalence was significantly higher in women than in men, 27.7% (1.2%) vs. 15.9% (1.1%) respectively. After adjusting for covariates, lower triglyceride levels were significantly associated with a decreased risk of suicidal ideation (OR=0.65; 95% CI=0.43-0.99) among men but no significant associations were observed among women. Additionally, there were no significant associations between any other measure of cholesterol levels and suicidal ideation in either men or women.

Cross-sectional design cannot infer temporality or the effects of changes in variables.

These results support the association between lower triglyceride levels and a reduced risk of suicidal ideation among Korean men over 65. Further studies are necessary to investigate gender difference and the biological mechanism.