Deficiency of fat-soluble vitamins in chronic pancreatitis: A systematic review and meta-analysis

Background and aims: Chronic pancreatitis (CP) patients are at risk for fat-soluble vitamins (A, D, E, K) deficiency, but available studies are small and heterogeneous. We conducted a systematic review and meta-analysis to determine the prevalence of fat-soluble vitamins deficiency in CP patients. Methods: Medline was searched up to January 2016 for case series and case-control studies reporting prevalence of fat-soluble vitamin deficiency in CP patients. The prevalent deficiency rate was pooled for included studies, and deficiency rate between CP and controls, with relative odds ratio (OR) and 95% confidence interval (CI) calculated for case-control studies. Results: Twelve studies including 548 patients included. With a random-effect model, the pooled prevalence rate of vitamin A, D and E deficiency were 16.8% (95%CI 6.9-35.7), 57.6% (95%CI 43.9-70.4) and 29.2% (95%CI 8.6-64.5) respectively, with considerable heterogeneity (I² = 75%, 87.1% and 92%). Only one study evaluated vitamin K deficiency. The pooled OR for vitamin D deficiency in CP cases compared with controls was 1.17 (95% CI 0.77-1.78). Sensitivity analyses showed lower prevalence of vitamin A and E, and higher prevalence of vitamin D deficiency in high-quality studies. The rate of pancreatic exocrine insufficiency did not seem affect the deficiency rates, while the use of different cut-offs influences results and heterogeneity for vitamin E, but not A. Conclusions: Fat-soluble vitamins deficiency is frequent in CP patients, with considerable heterogeneity. There is, however, no apparent increased risk of vitamin D deficiency in CP compared to controls. Larger, high-quality studies are necessary to better estimate the prevalence of fat-soluble vitamins deficiency, including vitamin K.