Increased risk of suicidality in patients with psoriasis: A Nationwide cohort study in Korea.

BACKGROUND: Psoriasis has a devastating psychological impact on patients' quality of life. However, the relationship between suicidality and psoriasis remains unclear. OBJECTIVE: This study analysed and compared the risk of suicidality (suicidal ideation, suicide attempt and completed suicide) between patients with psoriasis and the general population. METHODS: This nationwide, population-based, retrospective, cohort study analysed the Korean National Health Insurance Service claim data from 2005 to 2018. RESULTS: The study included 348,439 patients with psoriasis aged over 18 years and with age- and sex-matched controls. The risk of suicidality was higher in the psoriasis group than in the control group [adjusted hazard ratio (aHR) 1.21; 95% confidence interval (CI), 1.18-1.24]. The aHR of suicidality was higher in the psoriatic arthritis group (aHR, 1.46; 95% CI, 1.39-1.54) than in the psoriasis-alone group (aHR, 1.17; 95% CI, 1.13-1.20). However, the severity of psoriasis and suicidality showed no correlation (mild psoriasis group: aHR, 1.22; 95% CI, 1.18-1.25; moderate-to-severe psoriasis group: aHR, 1.16; 95% CI, 1.10-1.23). CONCLUSION: Patients with psoriasis have an increased risk of suicidality. In particular, the presence of arthritis in patients had a more significant effect on the risk of suicidality.