Suicidality and risk of suicidality in psoriasis: a critical appraisal of two systematic reviews and meta-analyses.

Abstract

Chi et al.¹ and Singh et al.² each conducted a systematic review and meta-analysis of observational studies examining the relationship between suicidality and psoriasis. Chi et al. included only cohort studies while Singh et al. included cohort, cross-sectional and case-control studies. The primary outcome, suicidality, was assessed in people with psoriasis (exposure) and people without psoriasis. Analyses were separated for suicidal ideation and behaviour. Chi et al. included five population-based cohort studies that were considered to be of high quality according to the Newcastle-Ottawa Scale (NOS). They found no significant increase in the risk of suicide [risk ratio (RR) 1·13, 95% confidence interval (CI) 0·87-1·46], suicide attempt (RR 1·25, 95% CI 0·89-1·75) or suicidality (RR 1·26, 95% CI 0·97-1·64) among people with psoriasis. Singh et al. included 18 studies that were rated to be of medium quality to high quality according to the NOS. They found a pooled odds ratio (OR) of 2·05 (95% CI 1·54-2·74) for suicidal ideation among patients with psoriasis. For suicidal behaviours (combined attempted and completed suicides) a pooled OR of 1·26 (95% CI 1·13-1·40) was obtained, suggesting a higher risk of these behaviours in people with psoriasis. Subgroup analysis showed that patients with psoriasis were more likely to attempt suicide (OR 1·32, 95% CI 1·14-1·54) and complete suicide (OR 1·20, 95% CI 1·04-1·39) than those without psoriasis. Singh et al. concluded that patients with psoriasis have a significantly higher risk of suicidal ideation, suicide attempts and completed suicides, while Chi et al. concluded that the available, limited, very low-quality evidence does not support the notion of an association between psoriasis on the one hand, and suicide, suicidal ideation and suicide attempts on the other.