The association between schizophrenia spectrum disorders and psoriasis: a large-scale population-based case-control study

T cell-mediated skin-brain axis: Bridging the gap between psoriasis and psychiatric comorbidities

Psoriasis, a chronic inflammatory skin condition, is often accompanied by psychiatric comorbidities such as anxiety, depression, suicidal ideation, and other mental disorders. Psychological disorders may also play a role in the development and progression of psoriasis. The intricate interplay between the skin diseases and the psychiatric comorbidities is mediated by the 'skin-brain axis'. Understanding the mechanisms underlying psoriasis and psychiatric comorbidities can help improve the efficacy of treatment by breaking the vicious cycle of diseases. T cells and related cytokines play a key role in the pathogenesis of psoriasis and psychiatric diseases, and are crucial components of the 'skin-brain axis'. Apart from damaging the blood-brain barrier (BBB) directly, T cells and secreted cytokines could interact with the hypothalamic-pituitary-adrenal axis (HPA axis) and the sympathetic nervous system (SNS) to exacerbate skin diseases or mental disorders. However, few reviews have systematically summarized the roles and mechanisms of T cells in the interaction between psoriasis and psychiatric comorbidities. In this review, we discussed several key T cells and their roles in the 'skin-brain axis', with a focus on the mechanisms underlying the interplay between psoriasis and mental commodities, to provide data that might help develop effective strategies for the treatment of both psoriasis and psychiatric comorbidities.

Multimorbidity clusters among people with serious mental illness: a representative primary and secondary data linkage cohort study

BACKGROUND

People with serious mental illness (SMI) experience higher mortality partially attributable to higher long-term condition (LTC) prevalence. However, little is known about multiple LTCs (MLTCs) clustering in this population.

METHODS

People from South London with SMI and two or more existing LTCs aged 18+ at diagnosis were included using linked primary and mental healthcare records, 2012-2020. Latent class analysis (LCA) determined MLTC classes and multinominal logistic regression examined associations between demographic/clinical characteristics and latent class membership.

RESULTS

The sample included 1924 patients (mean (s.d.) age 48.2 (17.3) years). Five latent classes were identified: 'substance related' (24.9%), 'atopic' (24.2%), 'pure affective' (30.4%), 'cardiovascular' (14.1%), and 'complex multimorbidity' (6.4%). Patients had on average 7-9 LTCs in each cluster. Males were at increased odds of MLTCs in all four clusters, compared to the 'pure affective'. Compared to the largest cluster ('pure affective'), the 'substance related' and the 'atopic' clusters were younger [odds ratios (OR) per year increase 0.99 (95% CI 0.98-1.00) and 0.96 (0.95-0.97) respectively], and the 'cardiovascular' and 'complex multimorbidity' clusters were older (ORs 1.09 (1.07-1.10) and 1.16 (1.14-1.18) respectively). The 'substance related' cluster was more likely to be White, the 'cardiovascular' cluster more likely to be Black (compared to White; OR 1.75, 95% CI 1.10-2.79), and both more likely to have schizophrenia, compared to other clusters.

CONCLUSION

The current study identified five latent class MLTC clusters among patients with SMI. An integrated care model for treating MLTCs in this population is recommended to improve multimorbidity care.