Having a medical condition was associated with an increased risk of suicide in a dose-response-like manner, such that the higher the burden of disability, the higher the risk of suicide, according to an observational study in Denmark.
An analysis of more than 6.6 million people found that nine medical condition categories including 31 specific conditions were associated with a statistically significant increased risk of suicide, with the exception of endocrine disorders, reported Søren Dinesen Østergaard, MD, PhD, of Aarhus University Hospital, and co-authors.
The associations were most pronounced for gastrointestinal conditions (incidence rate ratio [IRR] 1.7, 95% CI 1.5-1.8), cancers (IRR 1.5, 95% CI 1.4-1.6), and hematological conditions (IRR 1.5, 95% CI 1.3-1.6), they wrote in .
The risk was highest in the first 6 months following diagnosis and subsequently faded over time, although the risk after certain medical conditions remained elevated up to 15 years after onset.
"In both sexes, for those without mental disorder but, somewhat surprisingly, not for those with mental disorder, there was a clear relationship between the disability burden of medical disease and suicide: the higher the burden, the higher the risk of suicide," Østergaard and team noted.
"Individuals with mental disorder requiring psychiatric hospital treatment appear to be at such elevated risk of suicide that additional disability associated with medical conditions has little impact in this regard," they added.
Østergaard told that it was surprising that increased disability burden was not associated with increased risk of suicide among those individuals with prior psychiatric hospital treatment, and this finding suggests that the risk of suicide can reach "a ceiling due to the mental illness."
"From a clinical perspective," the authors wrote, "the results of this study underscore that there should be awareness of the risk of suicide not only among individuals with severe mental disorder but also for those with certain medical morbidities, especially in the period immediately after their diagnosis, and for those having a large disability burden due to multiple medical morbidities."
For this cohort study, Østergaard and team used data on 6,635,857 individuals living in Denmark at some point between 2000 and 2020 identified in the Danish Civil Registration System. A little more than half were women (n=3,337,613), and there were a total of 12,876 suicides.
The authors identified nine categories of medical conditions for the analysis, including circulatory, endocrine, pulmonary, gastrointestinal, urogenital, musculoskeletal, hematological, cancers, and neurological.
Individuals with these medical conditions were identified using data from medical/surgical hospital diagnoses assigned during inpatient admissions and outpatient and emergency visits from the Danish National Patient Register (but not from general practitioners and other private-practice physicians who do not report diagnostic data to this register), as well as prescriptions for disease-specific medications in the Danish National Prescription Register.
Among this cohort, suicide was more common for males than for females, which is also the case in the Danish general population, but the point estimates for the associations between medical conditions and suicide tended to be higher for females, the authors noted.
The study had some limitations. First, the authors used registry data, which may leave out individuals who did not seek treatment or did not have diagnoses reported. Second, the analysis was based only on data from Denmark, and the results may not be generalizable to other countries or regions.
Disclosures
The study was funded by a grant from the Lundbeck Foundation.
Østergaard reported receiving the 2020 Lundbeck Foundation Young Investigator Prize, ownership of units of mutual funds from multiple companies, ownership/past ownership of units of exchange-traded funds, and grants from the Novo Nordisk Foundation, Lundbeck Foundation, Danish Cancer Society, Central Denmark Region Fund for Strengthening of Health Science, Danish Agency for Digitisation Investment Fund for New Technologies, and Independent Research Fund Denmark.
One co-author reported receiving personal fees from the WHO. Another co-author was supported by grants from the Independent Research Fund Denmark.
Primary Source
JAMA Psychiatry
Østergaard SD, et al "Risk of suicide across medical conditions and the role of prior mental disorder" JAMA Psychiatry 2024; DOI: 10.1001/jamapsychiatry.2024.2561.