Vitamin D for treatment of non‐alcoholic fatty liver disease detected by transient elastography: A randomized, double‐blind, placebo‐controlled trial

Abstract Aim To evaluate the effects of vitamin D on transient elastography (TE, FibroScan) indices of liver steatosis (controlled attenuation parameter [CAP]) and fibrosis (liver stiffness measurement [LSM]) in adults with non‐alcoholic fatty liver disease (NAFLD). Patients and Methods In this randomized (2:1), double‐blind, single‐centre, 12‐month trial, patients with NAFLD were treated with vitamin D (1000 IU/day) (n = 201) or a matching placebo (n = 110). Two co‐primary outcomes were changes in CAP and LSM after 360 days of treatment versus baseline. Two main secondary outcomes were CAP/LSM changes after 180 days of treatment. Results Both CAP and LSM gradually decreased in vitamin D‐treated patients and slightly increased in the placebo arm. Vitamin D was superior to placebo for both primary outcomes (mean differences in CAP and LSM changes (−49.5 dB/m [95% CI −59.5 to −39.4] and −0.72 kPa [95% CI −1.43 to 0.00], respectively) and both secondary outcomes (−22.1 dB/m [−32.1 to −12.1] and −0.89 kPa [−1.61 to −0.17], respectively). Of a number of exploratory outcomes (change at 12 months vs. baseline), vitamin D reduced serum uric acid (−17.9 μmol/L [−30.6 to −5.2]), gamma‐glutamyltransferase (−8.9 IU/L [−15.5 to −2.3)] and fasting serum insulin levels (−5.1 pmol/L [−9.3 to −0.8]) as well as the homeostatic model assessment of insulin resistance index (−1.6 [−3.1 to −0.2]) (false discovery rate [5%]‐adjusted P ‐values between .0572 and .0952). Conclusion Low‐medium dose supplementation of vitamin D (1000 IU/day) over 12 months reduces TE indices of liver steatosis (CAP) and fibrosis (LSM) in NAFLD patients.