Having psoriasis is associated with an increased risk of any mental health disorder, not just depression, new research has found. The authors of both of the entirely separate studies, published as research letters in JAMA Dermatology, have urged doctors to be alert to the mental health of people they are treating for psoriasis.
The research team behind the first study*, all from Aarhus University Hospital in Denmark, used data from population-based registries covering all Danish hospitals to identify individuals born from 1900 to 1995 who had at least two hospital- or outpatient-based diagnoses of psoriasis from 1 January 1977 to 1 January 2012 and matched each of them with 10 age- and sex-matched controls identified using the Danish Civil Registration System.
They reported that among 13,675 individuals with psoriasis (50% male), the five- and 10-year cumulative incidences of any mental disorder were 2.6% and 4.9%. The overall hazard ratio (HR) for any mental disorder was 1.75, comparing people with psoriasis against controls. The HRs for selected mental disorders were 1.73 for vascular dementia, 1.64 for schizophrenia, 2.33 for bipolar disorder, 1.72 for unipolar depression, 1.88 for generalised anxiety disorder, and 2.06 for personality disorders.
However, patients’ educational level had a marked effect on the association: the risk of mental disorders among individuals with psoriasis who had completed short-term education gave an HR of 2.18, while those who had attained medium- and long-term educational levels HRs were 1.45 and 1.40, respectively.
The study authors pointed out that although previous research has found an association between psoriasis and depression, they were unaware of previously reported links with bipolar disorder, vascular dementia and the other mental health problems. They commented: “The findings reported herein support the need for an approach when treating individuals with psoriasis that focuses not only on their dermatologic condition, but also on their mental health.”
In the second study**, researchers led from The Catholic University of Korea in Seoul used population-based data (covering 1,116,789 people) from South Korea’s Health Insurance Research and Assessment Agency from 2002 to 2013, and identified people with psoriasis and depressive episode, other anxiety disorders, acute stress reaction, somatoform disorders, other neurotic disorders, and nonorganic sleep disorders. Their final study population included 12,762 patients with psoriasis.
They calculated that the risks of depressive episodes, anxiety disorders, somatoform disorders, neurotic disorders, and nonorganic sleep disorders were 2.19, 2.92, 2.62, 2.66, and 2.58 times higher respectively in patients with psoriasis than in control patients; these were slightly attenuated after adjusting for covariates.
The team also investigated the time to onset of mental health disorders in patients with psoriasis, and found that mental health disorders were shown to occur within two or three months of diagnosis of psoriasis. Men tended to have a shorter time to onset for most mental health disorders than women did, except for neurotic disorders and anxiety disorders. They said: “Therefore, when patients are diagnosed with psoriasis, multidisciplinary teams consisting of dermatologists and psychiatrists should be involved in the early stages of treatment.”
*Leisner MZ, Riis JL, Schwartz S, et al. Psoriasis and risk of mental disorders in Denmark. JAMA Dermatol. Published online May 08, 2019. DOI:10.1001/jamadermatol.2019.0039
**Bang CH, Yoon JW, Chun JH, et al. Association of psoriasis with mental health disorders in South Korea. JAMA Dermatol. Published online May 08, 2019. DOI:10.1001/jamadermatol.2019.0315