Long-term physical and mental health effects of unresolved disaster-related bereavement: evidence from an 8-year propensity score-matched cohort study.

Psychiatric outpatient utilisation among bereaved individuals showed a large initial spike and a second rise at year 8, far exceeding controls.

• Psychiatric outpatient utilisation among the bereaved increased from 10% pre-disaster to 38% in year 1, stabilised around 20%, and rose again to 38% in year 8.
• Controls showed only a gradual increase from 10% to 22% over the same period.
• The study followed 388 bereaved individuals matched to 1,552 controls using Korean National Health Insurance data.
• The second peak at year 8 may reflect unresolved or prolonged grief trajectories.

Difference-in-differences analyses showed significantly higher psychiatric outpatient visits in the bereaved group persisting across all post-disaster periods examined.

• Excess psychiatric outpatient visits were 2.87 (95% CI 1.52–4.22) in years 1–3.
• Excess visits persisted at 1.86 (95% CI 0.51–3.21) in years 4–6.
• Excess visits remained at 1.56 (95% CI 0.21–2.91) in years 7–8.
• Psychiatric admissions also increased significantly across all post-disaster periods.

Physical outpatient healthcare utilisation among the bereaved showed a delayed increase relative to psychiatric utilisation.

• Physical outpatient visits showed delayed excess increases, becoming significant only in years 4–6 and years 7–8.
• This delayed pattern contrasts with the immediate spike seen in psychiatric outpatient utilisation beginning in year 1.
• The findings suggest a temporal lag between mental and physical health consequences of disaster-related bereavement.

Cox proportional hazards models indicated elevated disease incidence risks across multiple organ systems and disease categories among bereaved individuals.

• Elevated risks were observed for infectious, benign neoplastic, endocrine, mental, neurological, digestive, dermatological, and musculoskeletal disorders.
• Elevated risks were also observed for abnormal findings and injury.
• These findings span a broad range of physical and mental health conditions, suggesting systemic health impacts of disaster-related bereavement.

The study used propensity score matching to create a retrospective cohort comparing bereaved individuals to controls over an 11-year observation window.

• 388 bereaved individuals were matched with 1,552 controls (approximately 1:4 ratio) using Korean National Health Insurance data.
• Healthcare utilisation and disease incidence were examined over three years pre-disaster and eight years post-disaster.
• Difference-in-differences and Cox proportional hazards models were used as the primary analytical methods.
• The Sewol ferry disaster occurred in April 2014 and resulted in the deaths of 304 people, predominantly high school students.

The study concluded that bereaved individuals exhibited unresolved grief eight years after the disaster, underscoring the need for long-term integrated physical and mental health support.

• Both psychiatric and physical healthcare utilisation remained elevated in the bereaved group through year 8.
• The authors highlight the need for 'long-term, integrated support addressing both mental and physical health beyond the immediate aftermath of disasters.'
• The recurrence of elevated psychiatric outpatient utilisation at year 8 (returning to 38%) was interpreted as evidence of persistent unresolved bereavement.