Suicide and dementia: A systematic review and meta-analysis of prevalence and risk factors

Dementia is a global health concern with increasing numbers of people living long enough to develop dementia. People with dementia (PwD) may be particularly vulnerable to suicidality. However, suicide in PwD has not been thoroughly explored. The objective of this review was to determine the prevalence and risk factors of suicide in PwD. Five databases were searched from inception to July 2023. Peer-reviewed publications reporting prevalence, risk factors or quantitative summary data for suicide outcomes in PwD were included. Random effects models were used to calculate the pooled prevalence and effect sizes. 54 studies met inclusion criteria. In PwD, the point prevalence of suicidal ideation was 10 % (95 %CI=6 %;16 %), 2-year period prevalence of suicide attempts was 0.8 % (95 %CI=0.3 %;2 %), 10-year period prevalence of suicide attempts was 8.7 % (95 %CI=6.0 %%;12.7 %) and the incidence of death by suicide 0.1 % (95 %CI=0.1 %;0.2 %). Compared to not having dementia, a diagnosis of dementia increased risk of suicidal ideation (OR=1.62[95 %CI=1.17;2.24]) but not risk of suicide attempt (OR=1.77 [95 %CI=0.85;3.69]) or death by suicide (OR=1.30 [95 %CI=0.81;2.10]). People with moderate dementia had significantly increased risk of suicidal ideation than those with mild dementia (OR=1.59[95 %CI=1.11;2.28]), younger PwD were at increased risk of dying by suicide (OR=2.82[95 %CI=2.16;3.68]) and men with dementia were more likely to attempt (OR=1.28[95 %CI=1.25;1.31]) and die by suicide (OR=2.88[95 %CI=1.54;5.39]) than women with dementia. This review emphasises the need for mental health support and suicide prevention in dementia care, emphasising tailored approaches based on age, symptoms, and being male.