Association Between Severity of Obstructive Sleep Apnea and Blood Markers of Liver Injury

Obstructive sleep apnea (OSA) may contribute to the development of nonalcoholic fatty liver disease. We performed a multisite cross-sectional study to evaluate the association between the severity of OSA and blood markers of liver steatosis (using the hepatic steatosis index), cytolysis (based on alanine aminotransferase activity), and significant liver fibrosis (based on the FibroMeter [Echosens] nonalcoholic fatty liver disease score) in 1285 patients with suspected OSA in France. After adjusting for confounders including central obesity, the risk of liver steatosis increased with the severity of OSA (P for trend < .0001) and sleep-related hypoxemia (P for trend < .0003 for mean oxygen saturation). Decreasing mean oxygen saturation during sleep also was associated independently with a higher risk of liver cytolysis (P for trend < .0048). Severe OSA conferred an approximate 2.5-fold increase in risk for significant liver fibrosis compared with patients without OSA, but the association between OSA severity and liver fibrosis was not maintained after adjusting for confounders

Independent association between nocturnal intermittent hypoxemia and metabolic dyslipidemia

International audienceBACKGROUND: There is growing evidence from animal models that intermittent hypoxemia (IH) may induce dyslipidemia. Altered lipid metabolism may contribute to the increased cardiovascular risk observed in obstructive sleep apnea (OSA). In this multisite, cross-sectional study, we tested the hypothesis that there is an independent association between nocturnal IH and dyslipidemia in OSA.METHODS: Fasting serum lipid levels were measured in 2,081 patients (638 women) undergoing nocturnal recording for clinical suspicion of OSA. Multivariate regression analyses were performed to evaluate the independent associations between oxygen desaturation index (ODI) and lipid profile after adjustment for potential confounders, including components of the metabolic syndrome (MS) or the MS itself. Adjusted OR for metabolic dyslipidemia (triglycerides [TG] ≥ 150 mg/dL and high-density lipoprotein cholesterol [HDL-C] ≤ 50 mg/dL for women and ≤ 40 mg/dL for men) according to quartiles of ODI were determined by logistic regression.RESULTS: Total cholesterol and low-density lipoprotein cholesterol were not associated with ODI. In contrast, nocturnal IH and OSA severity were associated with higher TG levels and lower HDL-C levels after adjustment for confounding factors. The association between ODI and TG and HDL-C levels was independent of the MS. Adjusted OR (95% CIs) for metabolic dyslipidemia were 1 (reference), 1.56 (1.24-1.96), 1.72 (1.29-2.29), and 1.93 (1.55-2.41) for ODI ≤ 7, &gt; 7 to ≤ 18, &gt; 18 to ≤ 38, and &gt; 38, respectively (P &lt; .0001 for linear trend).CONCLUSIONS: Nocturnal IH is independently associated with metabolic dyslipidemia, which may predispose patients with OSA to a higher risk of cardiovascular disease.</p