Association between bullous pemphigoid and psychiatric disorders: A systematic review and meta-analysis

Background and Objectives: Despite the well-established association between bullous pemphigoid (BP) and neurological diseases, the association between BP and psychiatric disorders remains unclear. In this study, we aimed to investigate the association between BP and various psychiatric disorders. Patients and Methods: PubMed, Embase, and Cochrane Library databases were searched for the identification of eligible cohort and case-control studies until May 30, 2021. Meta-analyses of crude estimates and adjusted estimates of odds ratio (OR) for case-control studies and hazard ratio (HR) cohort studies were then conducted. Results: Sixteen studies involving 637,285 patients were included for the qualitative synthesis. In the meta-analysis of adjusted estimates for case-control studies, patients with BP exhibited a significantly higher prevalence of psychiatric disorders (OR 1.77, 95 % confidence interval (CI) 1.07-2.92) and schizophrenia (OR 2.63, 95 % CI 2.033.39). Regarding the analysis of adjusted estimates of cohort studies, BP presented no significantly higher risk of depression (HR 1.09, 95 % CI 0.94-1.26) and schizophrenia (HR 1.35, 95 % CI 0.76-2.39). Conclusions: Psychiatric disorders, especially schizophrenia, have a significantly higher risk of preceding BP.