INTRODUCTION: Previous observational cohort studies showed an association between low serum lipid levels and suicide. This study was undertaken to examine the relationship between lipid parameters and impulsivity in suicidal patients with major depressive disorder (MDD).
METHODS: The current study included 100 patients with MDD distributed as 50 patients with recent suicidal attempts and 50 patients with no lifetime history of suicide. Participants were subjected to Structured Clinical Interview for DSM-IV Axis I Disorders (SCID I) to confirm the diagnosis. The risk of suicide was assessed through the Suicide Probability Scale (SPS), while the intent and seriousness of suicide were assessed through Beck's Suicidal Intent Scale. assessment of impulsivity was carried out through Barratt Impulsivity Scale. Serum lipid levels were measured in mg/dL after an overnight fast.
RESULTS: Total cholesterol (TC) was found significantly lower in the suicidal group compared to the non-suicidal depressed group (p = 0.040). Low high-density lipoprotein (HDL) level was significantly correlated with suicidality and high suicide intent was correlated with hopelessness. Logistic regression for lipid profile in both groups revealed significant TC and low-density lipoprotein (LDL) as predictors for suicide. There was no significant correlation between impulsivity and characteristics of depression, suicide probability, suicide intent, and all elements of the lipid profile.
CONCLUSIONS: Low TC and LDL could predict suicidal behavior in patients with MDD. Impulsivity could not be a mediator or predictor of suicide risk in patients with MDD.