Suicide and dementia: Systematic review and meta-analysis

Abstract

Introduction

To analyze the possible relationship between dementia in the elderly and the subsequent development of suicide ideation, attempts and/or completed suicides.

Methods

Systematic review and meta-analysis. Selection criteria: studies that analyzed the relationship between dementia and suicide. Search strategy: (i) in PubMed, EMBASE, CINAHL, IME and Lilacs until December 2018; (ii) manual search of the bibliography of selected articles; (iii) contact with leading authors. Article selection and data extraction according to a predefined protocol, including bias risk assessment, were performed by independent peer reviewers. The effect size index was calculated using Odds Ratio (OR) and its 95% confidence interval (random-effects model). Heterogeneity was evaluated with forest plots, Cochran's Q and I² index. Assessment of publication bias using funnel plots (“trim-and-fill” method) and the Egger test. The analysis of moderating variables was performed using a multiple meta-regression under a mixed-effects model.

Results

37 studies and 47 basic units of study were identified. Effect size of the association of dementia with: Suicidal Ideation OR = 1.37 (95% CI: .78–2.39); Suicide Attempt: OR = 2.24 (95% CI: 1.01–4.97); and Completed Suicide: OR = 1.28 (95% CI: .77–2.14). Possible publication bias was ruled out.

Conclusions

A trend toward suicidal events is identified, especially suicide attempts in people with dementia. Greater attention and care are recommended after a recent diagnosis of dementia, especially with adequate assessment of comorbidities, which could influence the occurrence and outcome of suicidal events.