Relation of nonalcoholic fatty liver disease to the metabolic syndrome: The Multi-Ethnic Study of Atherosclerosis

Background: An overlap exists between risk factors for metabolic syndrome (MetS) and nonalcoholic fatty liver disease (NAFLD). Objectives: We studied the association of MetS and its components with NAFLD in a multi-ethnic population. Methods: Cross-sectional study was designed, including 6814 participants from the Multi-Ethnic Study of Atherosclerosis. Liver fat content was measured with cardiac CT scans by using liver-to-spleen ratio of <1.0 and liver attenuation < 40 HU. Participants with heavy alcohol intake (>14 drinks/week for men and >7 drinks/week for women), self-reported history of cirrhosis, and missing information were excluded. A total of 4140 participants met the criteria for inclusion in the study. Results: The odds ratios (ORs) for presence of NAFLD were highest for persons with diabetes (OR, 4.16; 95% CI, 3.24-5.33), followed by presence of MetS (OR, 3.97; 95% CI, 3.26-4.83). Among components of MetS central obesity was associated with higher odds for presence (OR, 3.41; 95% CI, 2.77-4.20) and severity (OR, 5.58; 95% CI, 3.86-8.06) of NAFLD The ORs for moderate-to-severe NAFLD were higher for presence of MetS (OR, 5.92; 95% CI, 4.29-8.19)] by using <40 HU as the cutoff. However, odds of NAFLD increased significantly for combination of MetS components: 9.49 (95% CI, 5.67-15.90) and 24.05 (95% CI, 12.73-45.45) for presence of 3 and 5 MetS components, respectively. Conclusion: Components of MetS are associated with increased odds for presence and severity of NAFLD and increased risk with increasing number of MetS components in a multi-ethnic population of middle-to-old age persons.