Which patients with atopic eczema and psoriasis develop depression, anxiety and severe mental illness: is the evidence clear?

https://doi.org/10.1093/bjd/ljad009 Adesanya et al. have performed a highly relevant and excellent methodological review of the factors related to mental illness in people with atopic eczema (AE) and psoriasis.1 Interestingly, compared to targeted treatment, placebo increased depression and anxiety. Observational studies on psoriasis revealed that being female and having psoriatic arthritis increased the risk of depression and anxiety. Interestingly, moderate-to-severe psoriasis was associated with increased anxiety but not with depression, hypothetically indicating different disease mechanisms. More evidence is needed to explore those relationships and possible inflammatory pathways.2 Only 21 of 9053 of the screened studies met the inclusion criteria; 10 of those included were cross-sectional. All included observational studies and several of the randomized controlled trials had a moderate-to-high risk of bias. Despite the slightly better study quality, the trials did not allow for any conclusions to be drawn on the long-term effects of psoriasis and AE on mental illness, as the follow-up was ≤ 6 months.