Omega-3 Fatty Acid Supplementation Decreases Liver Fat Content in Polycystic Ovary Syndrome: A Randomized Controlled Trial Employing Proton Magnetic Resonance Spectroscopy

Abstract

Both nonalcoholic fatty liver disease (NAFLD) and the polycystic ovary syndrome (PCOS) have a strong association with multiple cardiovascular risk factors. A number of studies have demonstrated a link between these 2 disorders. In patients with NAFLD, several interventions have reduced liver fat content through improved hepatic aminotransferases and liver histology as well as imaging markers of hepatic steatosis. There are no data, however, showing that such interventions provide a long-term prognostic advantage for hepatic or cardiovascular outcomes. Few studies have investigated these interventions in women with NAFLD and PCOS. In several small clinical studies, dietary supplementation with marine-derived omega-3 fatty acids improved biochemical and ultrasonographic features of NAFLD suggesting that omega-3 fatty acids may have beneficial effects in NAFLD. This double-blind, randomized, crossover study investigated whether dietary supplementation with omega-3 fatty acids in women with PCOS decreased liver fat content. The effects of this intervention on plasma lipids, blood pressure, and other cardiometabolic risk factors were also assessed. The participants were 25 women with PCOS at a mean age of 32.7 years and with a mean body mass index of 34.8 kg/m 2 . The study was conducted at a tertiary cardiovascular research center. All study subjects were randomized to either 4 g daily of omega-3 fatty acids or a control for 8 weeks. Liver fat content was determined using proton magnetic resonance spectroscopy. Fat content was determined in the whole liver and in subgroups of HLF (liver fat >5%, defined as hepatic steatosis) and NLF (liver fat ≤5%). Liver fat content was significantly reduced in women with PCOS by treatment with omega-3 fatty acids compared with the control (10.2 ± 1.1 vs. 8.4% ± 0.9%; P = 0.022). Treatment was also associated with significant decreases in systolic blood pressure (mean, 124.1 ± 12.1 vs. 122.3 ± 14.5 mm Hg; P = 0.018), diastolic blood pressure (mean, 73.2 ± 8.4 vs. 69.7 ± 8.3 mm Hg; P = 0.005), and triglycerides (geometric mean, 1.19; 95% confidence interval, 1.03-1.47 vs. 1.02; 95% confidence interval, 0.93-1.18) mmol/L; P = 0.002). Most of the decrease in liver fat content associated with dietary omega-3 fatty acids occurred among women with hepatic steatosis (placebo, 18.2 ± 11.1 vs. omega-3 fatty acids, 14.8% ± 9.3%, P = 0.03).