S Yu1,2,3, C-L Yu4, Y-C Huang1,5, H-P Tu6,7, C-C E Lan2,8. 1. Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan. 2. Department of Dermatology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan. 3. Department of Dermatology, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan. 4. Taipei Cancer Center, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan. 5. Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan. 6. Department of Public Health and Environmental Medicine, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan. 7. Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan. 8. Department of Dermatology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
Abstract
BACKGROUND: Schizophrenia is a complex disease which proceeds from an interaction between genetic background and environmental factors. Recent studies showed T helper 17 (Th17) signalling, which is the main downstream immune response of psoriasis, is activated in schizophrenia. OBJECTIVE: To investigate whether patients with schizophrenia have higher risk of psoriasis. METHODS: In this nationwide retrospective cohort study, we analysed the 1 million enrollees' cohort from Taiwan's National Health Insurance Research Database. Psoriasis and schizophrenia were ascertained by International Classification of Diseases, 9th revision, Clinical Modification coding. The study cohort was comprised of enrollees diagnosed with schizophrenia during the period from 1 January 1996 through 31 December 2010, while the comparison population consisted of enrollees who had not been diagnosed with schizophrenia during the study period. Hazard ratio (HR) and 95% confidence interval (CI) were calculated for the risk of psoriasis associated with schizophrenia using Cox proportional hazard regression. RESULTS: The adjusted HR of psoriasis associated with schizophrenia was 2.32 (95% CI = 1.81-2.98). After 15 years, the cumulative incidence of psoriasis in patients with schizophrenia and comparison population was 2.82% and 1.17%, respectively. The Kaplan-Meier curves for the cumulative incidence of psoriasis in individuals with and without schizophrenia differed significantly (P < 0.0001, log-rank test). CONCLUSIONS: Patients with schizophrenia have higher risk of psoriasis, which may be due to common genetic susceptibilities and/or immunologic mechanisms in both diseases. Th17 signalling and pro-inflammatory cytokines may act as a link between these two diseases and are potential therapeutic targets for schizophrenia.
BACKGROUND:Schizophrenia is a complex disease which proceeds from an interaction between genetic background and environmental factors. Recent studies showed T helper 17 (Th17) signalling, which is the main downstream immune response of psoriasis, is activated in schizophrenia. OBJECTIVE: To investigate whether patients with schizophrenia have higher risk of psoriasis. METHODS: In this nationwide retrospective cohort study, we analysed the 1 million enrollees' cohort from Taiwan's National Health Insurance Research Database. Psoriasis and schizophrenia were ascertained by International Classification of Diseases, 9th revision, Clinical Modification coding. The study cohort was comprised of enrollees diagnosed with schizophrenia during the period from 1 January 1996 through 31 December 2010, while the comparison population consisted of enrollees who had not been diagnosed with schizophrenia during the study period. Hazard ratio (HR) and 95% confidence interval (CI) were calculated for the risk of psoriasis associated with schizophrenia using Cox proportional hazard regression. RESULTS: The adjusted HR of psoriasis associated with schizophrenia was 2.32 (95% CI = 1.81-2.98). After 15 years, the cumulative incidence of psoriasis in patients with schizophrenia and comparison population was 2.82% and 1.17%, respectively. The Kaplan-Meier curves for the cumulative incidence of psoriasis in individuals with and without schizophrenia differed significantly (P < 0.0001, log-rank test). CONCLUSIONS:Patients with schizophrenia have higher risk of psoriasis, which may be due to common genetic susceptibilities and/or immunologic mechanisms in both diseases. Th17 signalling and pro-inflammatory cytokines may act as a link between these two diseases and are potential therapeutic targets for schizophrenia.
Authors: Alexis E Cullen; Scarlett Holmes; Thomas A Pollak; Graham Blackman; Dan W Joyce; Matthew J Kempton; Robin M Murray; Philip McGuire; Valeria Mondelli Journal: Biol Psychiatry Date: 2018-06-28 Impact factor: 13.382