Psychotic (delusional) depression and completed suicide: a systematic review and meta-analysis

BACKGROUND: It remains unclear whether psychotic features increase the risk of completed suicides in unipolar depression. The present systematic review coupled with a meta-analysis attempts to elucidate whether unipolar psychotic major depression (PMD) compared to non-PMD presents higher rates of suicides. METHODS: A systematic search was conducted in Scopus, PubMed, and “gray literature” for all studies providing data on completed suicides in PMD compared to non-PMD, and the findings were then subjected to meta-analysis. All articles were independently extracted by two authors using predefined data fields. RESULTS: Nine studies with 33,873 patients, among them 828 suicides, met our inclusion criteria. PMD compared to non-PMD presented a higher lifetime risk of completed suicides with fixed-effect pooled OR 1.21 (95% CI 1.04–1.40). In a sub-analysis excluding a very large study (weight = 86.62%), and comparing 681 PMD to 2106 non-PMD patients, an even higher pooled OR was found [fixed-effect OR 1.69 (95% CI 1.16–2.45)]. Our meta-analysis may provide evidence that the presence of psychosis increases the risk of suicide in patients suffering from severe depression. The data are inconclusive on the contribution of age, mood congruence, comorbidity, and suicide method on PMD’s suicide risk. The lack of accurate diagnosis at the time of suicide, PMD’s diagnostic instability, and the use of ICD-10 criteria constitute the main study limitations. CONCLUSIONS: The presence of psychosis in major depression should alert clinicians for the increased risk of completed suicide. Thus, the implementation of an effective treatment both for psychotic depression and patients’ suicidality constitutes a supreme priority. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12991-018-0207-1) contains supplementary material, which is available to authorized users.