Mortality in bullous pemphigoid: A systematic review and meta-analysis of standardized mortality ratios

There are inconsistent data on mortality rates in patients with bullous pemphigoid (BP). Trends in mortality in BP throughout the years are yet to be established. The aim of the present study was to study the mortality in BP patients relative to the general population and to estimate trends in standardized mortality over the past 30 years. We performed a systematic review and meta-analysis of observational studies in Medline, Embase and Scopus (1823-2017). Reference lists of included studies were also searched for eligible studies. Quality of evidence was assessed using the Newcastle-Ottawa Scale (NOS). A meta-analysis was performed using random-effects models to estimate pooled standardized mortality ratios (SMR) with 95% confidence intervals (CI). Meta-regression models were used to investigate the secular trends in SMR. Ten studies were included covering the period 1960-2015 (1736 patients, 746 deaths). Pooled all-cause SMR was 3.6 (95% CI, 2.6-5.0). There was no trend in all-cause SMR across the last three decades (regression coefficient 0.02 [change in logSMR/year]; 95% CI, 0.04-0.08; P = 0.545). In conclusion, there is a 3.6-fold increased mortality among patients with BP as compared with the age-matched general population. The excess mortality in BP has not changed significantly over the past 30 years.