Suicide risk within 1 year of dementia diagnosis in older adults: a nationwide retrospective cohort study

Suicide risk within 1 year of dementia diagnosis in older adults: a nationwide retrospective cohort study

J Psychiatry Neurosci 2021;46(1):E119-E127 | PDF | Appendix

Jae Woo Choi, PhD; Kang Soo Lee, MD, PhD; Euna Han, PhD

Background: Although severe dementia could protect against suicide death by decreasing a person’s capacity to implement a suicide plan, patients with early dementia may have better cognition, giving them more sustained insight into their disease and better enabling them to carry out a suicide plan. This study investigated suicide risk in older adults within 1 year of receiving a diagnosis of dementia.

Methods: This study used National Health Insurance Service Senior Cohort data and included 36 541 older adults with newly diagnosed dementia (a Mini-Mental State Examination score ≤ 26 and a Clinical Dementia Rating score ≥ 1 or a Global Deterioration Scale score ≥ 3), including Alzheimer disease, vascular dementia and other/unspecified dementia, from 2004 to 2012. We selected older adults without dementia through 1:1 propensity-score matching using sex, age, comorbidities and index year, with follow-up throughout 2013. We estimated adjusted hazard ratios (AHRs) of suicide deaths within 1 year after diagnosis using a time-dependent Cox proportional hazards model.

Results: We verified 46 suicide deaths during the first year after a dementia diagnosis. Older adults with dementia had an increased risk of suicide death compared to those without dementia (AHR 2.57; 95% confidence interval [CI] 1.49–4.44). Older adults with Alzheimer disease (AHR 2.50; 95% CI 1.41–4.44) or other/unspecified dementia (AHR 4.32; 95% CI 2.04–9.15) had an increased risk of suicide death compared to those without dementia. Patients with dementia but without other mental disorders (AHR 1.96; 95% CI 1.02–3.77) and patients with dementia and other mental disorders (AHR 3.22; 95% CI 1.78–5.83) had an increased risk of suicide death compared to patients without dementia. Patients with dementia and schizophrenia (AHR 8.73; 95% CI 2.57–29.71), mood disorders (AHR 2.84; 95% CI 1.23–6.53) or anxiety or somatoform disorders (AHR 3.53; 95% CI 1.73–7.21), respectively, had an increased risk of suicide death compared to patients with those conditions but without dementia.

Limitations: This study examined only elderly patients in South Korea, a population with a substantially higher suicide rate than the global population. Caution must be exercised when generalizing the results to populations with dissimilar backgrounds.

Conclusion: Patients with dementia had an increased risk of suicide death within 1 year after diagnosis compared to those without dementia.


Submitted Dec. 23, 2019; Revised Jun. 26, 2020; Accepted Jul. 10, 2020; Early-released Oct. 29, 2020

Acknowledgments: The authors thank Enago (enago@enago.co.kr) for English-language editing.

Affiliations: From the College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, South Korea (Choi, Han); and the Department of Psychiatry, CHA University College of Medicine, Bundang CHA Hospital, Gyeonggi-do, South Korea (Lee).

Competing interests: None declared.

Contributors: All authors designed the study. J. Choi and E. Han acquired the data, which all authors analyzed. All authors wrote and reviewed the article. All authors approved the final version to be published and can certify that no other individuals not listed as authors have made substantial contributions to the paper.

Funding: This work was supported by the National Research Foundation of Korea [grant number: 2019R1A2C1003259], the Yonsei University Research Fund (Post Doc. Researcher Supporting Program) of 2019 [2019-12-0129], and the National Research Foundation of Korea [grant number: 2020R1I1A1A01053104].

Content licence: This is an Open Access article distributed in accordance with the terms of the Creative Commons Attribution (CC BY-NC-ND 4.0) licence, which permits use, distribution and reproduction in any medium, provided that the original publication is properly cited, the use is non-commercial (i.e. research or educational use), and no modifications or adaptations are made. See: https://creativecommons.org/licenses/by-nc-nd/4.0/

DOI: 10.1503/jpn.190219

Correspondence to: E. Han, College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, 162-1 Songdo-Dong, Yeonsu-Gu, Incheon, South Korea; eunahan@yonsei.ac.kr