Liver phenotypes in PCOS: Analysis of exogenous and inherited risk factors for liver injury in two European cohorts

BACKGROUND & AIMS

Fatty liver disease (FLD) is common in women with polycystic ovary syndrome (PCOS). Here, we use non-invasive tests to quantify liver injury in women with PCOS and analyse whether FLD-associated genetic variants contribute to liver phenotypes in PCOS.

METHODS

Prospectively, we recruited women with PCOS and controls at two university centres in Germany and Poland. Alcohol abuse was regarded as an exclusion criterion. Genotyping of variants associated with FLD was performed using TaqMan assays. Liver stiffness measurements (LSM), controlled attenuation parameters (CAP) and non-invasive HSI, FLI, FIB-4 scores were determined to assess hepatic steatosis and fibrosis.

RESULTS

A total of 42 German (age range 18-53 years) and 143 Polish (age range 18-40 years) women with PCOS, as well as 245 German and 289 Polish controls were recruited. In contrast to Polish patients, Germans were older, presented with more severe metabolic profiles and had significantly higher LSM (median 5.9 kPa vs. 3.8 kPa). In the German cohort, carriers of the PNPLA3 p.I148M risk variant had an increased LSM (p = .01). In the Polish cohort, the minor MTARC1 allele was linked with significantly lower serum aminotransferases activities, whereas the HSD17B13 polymorphism was associated with lower concentrations of 17-OH progesterone, total testosterone, and androstenedione (all p < .05).

CONCLUSIONS

FLD is common in women with PCOS. Its extent is modulated by both genetic and metabolic risk factors. Genotyping of variants associated with FLD might help to stratify the risk of liver disease progression in women suffering from PCOS.

Effect of Short-Term Vitamin D Correction on Hepatic Steatosis as Quantified by Controlled Attenuation Parameter (CAP)

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in Western countries. A meta-analysis has confirmed decreased serum 25-hydroxyvitamin D levels in NAFLD patients. This intervention study investigates whether vitamin D correction ameliorates hepatic steatosis.

METHODS

We prospectively recruited 40 patients from an outpatient liver clinic with vitamin D deficiency (serum 25-hydroxyvitamin D < 20 ng/ml). Controlled attenuation parameter (CAP) during transient elastography quantified hepatic steatosis. Patients with significant liver fat accumulation were included, which was defined by a CAP value >/= 280 dB/m. Patients received 20,000 IU vitamin D/week for six months, while vitamin D status, liver function tests (LFTs), CAP and body composition were monitored.

RESULTS

The cohort comprised 47.5% women (age 54.9 +/- 12.1 years; BMI 29.5 +/- 3.0 kg/m2). Mean serum vitamin D level was 11.8 +/- 4.8 ng/ml. CAP decreased significantly from baseline (330 +/- 32 vs. 307 +/- 41 dB/m) during supplementation (P = 0.007). A mean CAP reduction relative to baseline was demonstrated at four weeks and three and six months: -5.3 +/- 13.8%; -6.0 +/- 14.6% and -6.4 +/- 13.0%, respectively. During these time points, restoration of serum vitamin D levels was observed (34.6 +/- 12.9, 36.3 +/- 10.2, 34.8 +/- 9.8 ng/ml; P < 0.0001). Liver function tests and body composition remained unchanged.

CONCLUSIONS

Hepatic steatosis, as assessed by CAP, significantly improves after only 4 weeks of vitamin D correction. Hepatic steatosis is a dynamic process, that can be monitored in the short-term using such non-invasive methods.