Serum lipids and suicidal risk among patients with schizophrenia spectrum disorders: Systematic review and meta‐analysis

Objective A systematic review of literature was conducted to determine the association between serum lipids and suicidality in people with schizophrenia spectrum disorders. Methods We undertook a systematic search of multiple databases for studies that ascertained an association between serum lipids and suicidality in adult patients with schizophrenia spectrum disorders (18–65 years) from database inception to 2 September 2020. Qualitative analysis was done using National Institute of Health (NIH) scales. The standard mean difference (SMD) and 95% confidence intervals (CI) were calculated for each study and standardized relative to the study. Adjusted p ‐value, Z‐test, and heterogeneity were calculated, as well as testing for publication bias. Results Of 1262 records identified, 17 studies ( n = 3113) were included in our systematic review, while 11 studies were included in the meta‐analysis. The majority of studies (11) rated fair on qualitative analysis. Data from seven studies ( n = 1597) revealed a medium effect size for an association between low total cholesterol and suicide attempts (SMD −0.560; 95% CI: 0.949–0.170; p = 0.005). People with history of suicide attempt had a mean cholesterol value 0.56 SD lower than the mean in those without suicide attempts. There were differences in how a suicide attempt was defined and there was high heterogeneity ( I 2 = 83.3%). No significant association was found between any of the serum lipid parameters and suicide ideation. Funnel‐plot analysis suggested small study effects with publication bias. Conclusions Suicide attempts in people with schizophrenia spectrum disorders are associated with low mean total cholesterol levels.