Context: Polycystic ovary syndrome (PCOS) has been linked to non-alcoholic fatty liver disease (NAFLD) that carries an increased risk of liver cirrhosis. The Enhanced Liver Fibrosis (ELF) score comprises serum hyaluronic acid (HA), procollagen III N-terminal peptide (PIIINP) and tissue inhibitor of metalloproteinase-1 (TIMP1) that correlate with hepatic fibrosis staging.
Objective: To determine the effect of vitamin D supplementation on liver fibrosis markers.
Design: A randomized, double-blind, placebo-controlled study.
Setting: A tertiary care setting in the UK.
Participants: Forty obese women with PCOS.
Intervention: Randomization to either vitamin D 3200 IU daily or placebo for 3 months.
Main outcome measures: The primary outcome was ELF score change, with alanine aminotransferase (ALT), hormonal, metabolic and cardiovascular risk marker changes as secondary outcomes.
Results: Vitamin D supplementation showed an ELF score reduction compared to placebo (−7.6±9.6% vs. 0.4±8.9; P=0.02) with a corresponding decrease in the component fibrosis markers; HA (−31.2±31.9% vs 16.9±57.1; P<0.01) and PIIINP (−18.6±20.4% vs 8.0±27.2; P<0.01), and a fall in ALT with vitamin D treatment (−16.7±25.7% vs 21.9±28.3; P<0.01). Within group analysis revealed vitamin D alone showed ELF score reduction (P<0.01) with a reduction in HA (P<0.01), PIIINP (P<0.01) and TIMP-1 (P<0.05). There were no changes in the hormonal, metabolic or cardiovascular risk profiles between groups.
Conclusion: Vitamin D supplementation improved hepatic fibrosis markers (HA, PIIINP, TIMP-1) in obese women with PCOS with a reduction in the ELF score.