Association of plasmatic lipids and suicidal ideation in bipolar disorders: a FACE-BD cohort study

Suicidal ideation and behaviours are highly prevalent in the general population and especially in patients with bipolar disorders (BD). Numerous studies examined the associations between lipids and suicidal behaviour, with conflicting results. Our study aimed to analyse retrospectively and prospectively whether plasma lipids (total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides) are associated with suicidal ideation and suicide attempts in BD patients. Clinical and biological data from the FondaMental Advanced Centre of Expertise for Bipolar Disorders (FACE-BD) cohort were used, including a lifetime history of suicidal ideation and suicide attempts. To assess factors associated with suicidal ideation, multivariate analyses using logistic regression with multiple adjustments were performed. 3736 BD patients were included at baseline, and 2245 had longitudinal data at one year. Exploratory longitudinal analysis showed that, in patients with no lifetime suicidal ideation at inclusion, baseline triglyceride level was associated with incident suicidal ideation during one-year follow-up, but it is hypothesis-generating rather than predictive. In multivariate analysis, at inclusion, total cholesterol (aOR=1.10, CI 95%[1.02;1.17], p = 0.008) and LDL cholesterol (aOR=1.10, CI 95%[1.01 to 1.17], p = 0.028) were positively associated with reporting history of suicidal ideation and suicidal attempts (aOR=1.02, CI 95% [1.03;1.18], p = 0.006 for total cholesterol and (aOR=1.14, CI 95% [1.05 to 1.23], p < 0.001 for LDL cholesterol). After further adjustment for psychotropic medications, only associations with suicide attempts remained significant. Our results suggested that total cholesterol and LDL cholesterol were positively associated with lifetime suicidal ideation and behaviours. Additional longitudinal studies on large cohorts over longer periods are needed.