Prevalence of primary painless chronic pancreatitis: A systematic review and meta-analysis

Background/objectives: While pain is the predominant symptom of chronic pancreatitis (CP), a subset of patients may experience a painless course. This systematic review aimed to determine the prevalence of primary painless CP. Methods: MEDLINE (PubMed), EMBASE and Web of Science Core Collection databases were searched for published studies through September 15, 2020 that included at least 10 consecutive patients with CP and which reported the number with painless CP. The presence of a history of recurrent acute pancreatitis (RAP), exocrine pancreatic insufficiency (EPI), diabetes mellitus (DM) and pancreatic adenocarcinoma (PA) in the painless CP patients was also recorded. A random effects model was used to determine pooled prevalence estimates with 95% confidence intervals (95% CI). Results: Among the 5057 studies identified and screened, 42 full-text articles were included in the final analysis. There were a total of 14,277 patients with CP among whom 1569 had painless CP. The pooled prevalence of painless CP was 12% (95% CI 10-15%). Among a subset of studies that reported on calcifications (n = 11), DM (n = 12), EPI (n = 8) and history of RAP (n = 14), the pooled prevalence estimates were 96% (95% CI 73-100%), 51% (95% CI 32-70%), and 47% (95% CI 15-81%), respectively. Alcohol, idiopathic/genetic and other etiologies were attributed tobe the cause of painless CP in 32.4%, 56.9% and 8.9% patients, respectively. Conclusion: Approximately one in ten patients with CP have primary painless disease with the majority being attributable to an idiopathic/genetic etiology. Further research is needed to determine the optimal management of these patients. (C) 2021 IAP and EPC. Published by Elsevier B.V. All rights reserved.