Lin HT, et al. - Researchers sought to determine if insomnia increases the risk of suicide attempts and verify the effects of insomnia on suicide risk. They identified that for suicide attempts, insomnia, low income, drug dependence, and mental disorders were the independent risk factors. A high risk of suicide due to insomnia was demonstrated by female patients and those aged 25–44 years. Insomnia, mental disorders, and low income displayed a synergistic effect on suicide attempts. Clinicians are recommended to consider the mental status and income level of insomnia patients.

Methods

• Researchers performed a cohort study using 2000–2013 hospitalization data from the National Health Insurance Research Database (NHIRD) to track the rate of suicide attempts among insomnia patients aged 15 years or older.
• Furthermore, based on sex, age, and date of hospitalization, they conducted a 1:2 pairing to identify the reference cohort (patients without insomnia).
• The effects of insomnia on suicide risk was assessed using Cox proportional hazard model.

Results

• Between 2000 and 2013, a total number of 479,967 patients aged 15 years or older were hospitalized (159,989 patients with insomnia and 319,978 patients without insomnia).
• Suicide risk in insomnia patients was 3.533-fold that of patients without insomnia, after adjusting for confounders (adjusted hazard ratio [HR]=3.533, 95% confidence interval [CI]=3.059–4.080, P < 0.001).
• Researchers noted that suicide risk in low-income patients was 1.434-fold (adjusted HR=1.434, 95% CI=1.184–1.736, P < 0.001) that of non-low-income patients.
• Patients with drug dependence and with mental disorders had a suicide risk 1.592-fold (adjusted HR=1.592, 95% CI=1.220–2.077, P < 0.001) and 4.483-fold (adjusted HR=4.483, 95% CI=3.934–5.109, P < 0.001) that of patients without drug dependence and without mental disorders, respectively.
• Suicide risk in female insomnia patient population was 4.186-fold (adjusted HR=4.186, 95% CI=3.429–5.111, P < 0.001) that of female patients without insomnia.
• Suicide risk in insomnia patients was 5.546-fold (adjusted HR=5.546, 95% CI=4.236–7.262, P < 0.001) that of patients without insomnia, among patients aged 25–44 years.
• In addition, patients with mental disorders and insomnia exhibited a suicide risk 18.322-fold that of patients without insomnia and mental disorders (P < 0.001).