title: Frequency of progression from acute to chronic pancreatitis and risk factors: a meta-analysis.
abstract: OBJECTIVE
  Acute pancreatitis (AP) and chronic pancreatitis (CP) traditionally have been thought to be distinct diseases, but there is evidence that AP can progress to CP. Little is known about the mechanisms of pancreatitis progression. We performed a meta-analysis to quantify the frequency of transition of AP to CP and identify risk factors for progression.
  
  
  METHODS
  We searched PubMed, Scopus, and Embase for studies of patients with AP who developed CP, published from 1966 through November 2014. Pooled prevalence and 95% confidence intervals (CIs) were calculated for these outcomes, and sensitivity, subgroup, and meta-regression analyses were conducted.
  
  
  RESULTS
  We analyzed 14 studies, which included a total of 8492 patients. The pooled prevalence of recurrent AP was 22% (95% CI, 18%-26%), and the pooled prevalence of CP was 10% (95% CI, 6%-15%). Sensitivity analyses yielded a pooled prevalence of CP of 10% (95% CI, 4%-19%) and 36% (95% CI, 20%-53%) in patients after the first occurrence and recurrent AP, respectively. Subgroup analyses found alcohol use and smoking to be the largest risk factors for the development of CP, with pooled prevalence values of 65% (95% CI, 48%-56%) and 61% (95% CI, 47%-73%), respectively. Meta-regression analysis found that men were more likely than women to transition from AP to CP.
  
  
  CONCLUSIONS
  Ten percent of patients with a first episode of AP and 36% of patients with recurrent AP develop CP; the risk is higher among smokers, alcoholics, and men. Prospective clinical studies are needed to study pancreatitis progression.
authors: Department of Surgery, University of Auckland, Auckland, New Zealand.
authors: Sharanya J
authors: SJ
authors: Sankaran
authors: Department of Surgery, University of Auckland, Auckland, New Zealand.
authors: Amy Y
authors: AY
authors: Xiao
authors: Department of Surgery, University of Auckland, Auckland, New Zealand.
authors: Landy M
authors: LM
authors: Wu
authors: Department of Surgery, University of Auckland, Auckland, New Zealand.
authors: John A
authors: JA
authors: Windsor
authors: Division of Gastroenterology, Hepatology, and Nutrition, University of Florida College of Medicine, Gainesville, Florida.
authors: Christopher E
authors: CE
authors: Forsmark
authors: Department of Surgery, University of Auckland, Auckland, New Zealand. Electronic address: max.petrov@gmail.com.
authors: Maxim S
authors: MS
authors: Petrov
mesh_terms: D000208:Acute Disease; D000428:Alcohol Drinking / Q000453:epidemiology; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D010195:Pancreatitis / Q000453:epidemiology / Q000473:pathology*; D050500:Pancreatitis, Chronic / Q000453:epidemiology* / Q000473:pathology; D015995:Prevalence; D012008:Recurrence; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology
keywords: Natural Course; Pancreatic Disease; Prevalence; Systematic Review