OBJECTIVES : Non-alcoholic fatty liver disease (NAFLD), the most common cause of chronic liver disease, is increasing alongside known risk factors like metabolic syndrome (METS). This study used the IBM^® MarketScan^® Explorys^® Claims-EMR Dataset to explore progression to NAFLD in METS patients.

METHODS : Adults with METS (ICD-9:277.7; ICD-10:E88.1) were identified and stratified by NAFLD risk. The first METS diagnosis served as the index date; continuous eligibility for 6 months prior and 24 months following index was required. Patients with baseline diagnoses of NAFLD or diagnoses of alcohol dependence, hepatitis, liver or metastatic cancer,or biliary cirrhosis at any time were excluded. High (HR) and low (LR) NAFLD risk groups were defined at index based on evidence of any of the following: BMI ≥25, AST or ALT ≥30, diabetes, a liver biopsy, or bariatric surgery. Clinical characteristics and the incidence of NAFLD were compared between groups.

RESULTS : The sample included 21,186 patients with METS; 40% of the sample (8,518) was classified as having a high risk of NAFLD. HR patients were older (54.9 v. 50.7) and more likely to be male (43.4% v. 37.8%) compared to LR patients, p<0.001. A higher proportion of HR patients (6.9% v. 3.9%) progressed to NAFLD and within a shorter time (253 v. 316 days) than LR patients. Clinically, progressors were more likely to have elevated liver enzymes, low HDL, hypertension, hyperlipidemia, diabetes, and obesity at baseline compared to non-progressors. Progression to NAFLD also resulted in a ~3-fold increase in annual healthcare costs over the study period compared to METS alone.

CONCLUSIONS : Within a population of METS patients, some patients remain at higher risk of NAFLD. Identification and treatment of METS patients with elevated NAFLD risk may help to delay the onset of chronic liver disease, improve outcomes, and mitigate increasing costs of care.