Co-morbidities Help Predict NAFLD Progression

Abstract

Introduction: NAFLD is an increasingly prominent phenomenon with over 64 million people affected yearly in the US, with an annual economic burden of more than $100 billion. It is the most common liver disorder in Western countries, with metabolic syndrome being one of the major risk factors, and other associated comorbidities increasing in prevalence. Understanding which disorders predispose to the development and progression of NAFLD to NASH and cirrhosis will help us in prognostication, evaluation and treatment. Methods: We conducted a retrospective cohort study of outpatients with metabolic syndrome and NAFLD who underwent liver biopsy between 2008 and 2016. Biopsies were categorized based on the NAFLD activity score (NAS), which is the unweighted sum of steatosis grade, lobular inflammation and hepatocellular ballooning. NAS of 0-2 was classified as non-NASH, 3-4 as borderline and 5-8 as NASH. Patients with cirrhosis were excluded as NAS score is not an accurate representation of severity of disease in this group. Chi-square was used for categorical values and analysis of variance was used for numerical values. Results: 114 patients were included in the final analysis. Non-NASH, borderline steatohepatitis and NASH were seen in 8 (70%), 59 (51.7%) and 47 (41.2%), respectively. There was no statistical significance in age, gender, BMI or ethnicity between the three groups, however the cohort was predominantly white (82.4%). PCOS and CAD (coronary artery disease) were seen in only 4.4% and 1.8% of the population, respectively. NAFLD patients with CAD, GS (gallstone disease), OSA (obstructive sleep apnea) and PCOS were more likely to have borderline steatohepatitis or NASH (p < 0.05). Conclusion: NAFLD has been closely linked with various diseases, including metabolic syndrome, CAD, PCOS, hypothyroidism, OSA and hypopituitarism. Liver biopsies are helpful in determining severity of disease. Our study reveals a statistical significance between the three groups of NAFLD, in relation to CAD, PCOS, OSA and GS. This holds tremendous clinical value. However, this should be interpreted with some caution, as there were very few patients with PCOS and CAD, with no patients with either disease in the non-NASH group. By analyzing which comorbid conditions result in higher NAS, we may be able to predict which patient populations will develop more severe liver disease. Further evaluation with a larger population cohort is warranted to confirm these results and possibly create a prediction score.Figure: NASH, non-alcoholic steatohepatitis; BMI, body mass index; CAD, coronary artery disease; GS, gallstone disease; OSA, obstructive sleep apnea; PCOS, polycystic ovarian syndrome; NAS, NAFLD activity score. aNon-NASH is defined as patients with NAS 0-2. bBorderline steatohepatitis is defined as patients with NAS 3-4. cNASH is defined as patients with NAS 5-8. dNumber (%) of patients with the specified disease within each group.