Suicide in neurodegenerative diseases: a systematic review.

Clinical Snapshot

Key Findings

• P Value: Not reported

• Effect Size: Not quantified — no pooled effect size reported; narrative synthesis only

• Primary Outcome: Patients with AD, PD, ALS, and MS are at higher risk of suicidality compared to the general population, despite distinct pathophysiological profiles across diseases

• Nnt Or Sensitivity: Not applicable — no quantitative synthesis performed. Key qualitative findings: depression and low social connectivity are the most prevalent modifiable risk factors across all four diseases; suicidality risk is highest in the early post-diagnosis period for PD, ALS, and MS; findings in AD are described as 'confusing,' likely reflecting cognitive impairment limiting self-report validity

• Confidence Interval: Not reported

Clinical Application

The identified risk factors (depression, social isolation) are clinically assessable using validated tools already in routine use (e.g., PHQ-9, GDS, MADRS). Routine suicidality screening at diagnosis and during early disease course is feasible in specialist neurology and general practice settings. Referral pathways to psychiatry and psychology exist in most health systems. However, the evidence base is insufficient to support specific screening protocols or intervention thresholds. In Australia, all four diseases carry significant burden: approximately 400,000 Australians live with MS, PD affects approximately 100,000, and ALS/MND affects approximately 2,100 at any time. The RACGP Red Book and mental health care plans (MBS Item 2700 series) provide frameworks for depression screening and psychological referral in chronic disease. Beyondblue and Lifeline provide accessible crisis support. Notably, voluntary assisted dying (VAD) is now legal in all Australian states and territories, with ALS and MS among conditions that may qualify — this creates a distinct clinical and ethical context for suicidality assessment not addressed by this review. TGA-approved pharmacotherapies for depression in neurological disease (SSRIs, SNRIs) are PBS-listed. The MND Australia and MS Australia organisations provide peer support addressing social isolation. RACGP guidelines recommend routine mental health assessment in chronic neurological disease, consistent with this review's findings. Adults newly diagnosed with or living with Parkinson's disease, ALS, multiple sclerosis, or Alzheimer's disease; particularly those with comorbid depression or social isolation. Clinicians in neurology, psychiatry, palliative care, and general practice managing these patient groups.

Abstract

BACKGROUND AND OBJECTIVE: Suicide is a public health issue, which differs from suicidality, the continuum from suicidal ideation to the suicidal act, including suicide attempts and completed suicide. The main goal of the present study is to determine the relationship between Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS) with suicidality. METHODS: This is a systematic review aiming to determine the relationship between AD, PD, ALS, and MS with suicidality following PRISMA 2020 guidelines by collecting cross-sectional, case-control, and cohort studies; case series; case reports; and retrospective and prospective studies from Google Scholar, PubMed, and Cochrane Library. The protocol of this systematic review was registered on PROSPERO; the registration number is CRD420261422354. RESULTS: From 2247 records identified from electronic databases, only 24 articles were included: three studies focusing on AD, nine on PD, and six studies focusing on ALS and MS, respectively. These studies exhibited moderate to low risk of bias. Despite the broad differences regarding the neurochemistry, pathophysiology, diagnosis, symptoms, and treatments of the selected diseases, patients are at a higher risk of suicidality. Depression and low social connectivity are the most prevalent risk factors. Suicidality is mainly detected during the first years post-diagnosis in PD, ALS, and MS patients, while the results in AD are confusing. CONCLUSIONS: Data about this topic is scarce and largely varying. Further research is required to elucidate this paradigmatic realm, fostering awareness, enhancing therapies, and providing explanations and interpretations of the mechanisms involved.

References

1. 1.Abidar, S., Nhiri, M., & Bianchi, V. (2026). Suicide in neurodegenerative diseases: a systematic review. Neurological Sciences: Official Journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology. Advance online publication. PubMed ID: 42521895