Clinical and Metabolic Characteristics of Non-Alcoholic Fatty Liver Disease Patients in Saudi Arabia: Data from the Systematic Observatory Liver Disease (SOLID) Registry

Background and Aims: The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing in Saudi Arabia (SA), but descriptions of the clinical and metabolic characteristics of these patients are limited. The present study aims to fill this gap. Methods: Demographic, clinical, and laboratory data of all NAFLD patients from 2009 to 2019 were retrieved from the Systematic Observatory Liver Disease Registry (SOLID) [n=832 (337 males; 495 females); mean (+/- standard deviation, SD) age was 42.6 +/- 13.6 years; mean body mass index (BMI) was 35.0 +/- 9.3kg/m(2)]. Non-invasive surrogate scores of fibrosis (eg AST to Platelet Ratio Index (APRI), Fibrosis-4 (FIB-4), and NAFLD fibrosis (NFS) scores) were calculated and analyzed. In addition, data from NAFLD patients with normal and high alanine aminotransferase (ALT) were compared using two different methods: the standard laboratory reference range which defines normal as ALT<61 IU/L, and the range proposed by a recent national study which sets upper limits of normal ALT at 33 IU/l for men and 22 IU/l for women. Results: Hyperlipidemia was the most common comorbidity (41.7%), followed by type 2 diabetes mellitus (T2DM) (35.3%) and hypertension (28.4%). Prevalence of advanced fibrosis varied widely across definitions [FIB-4, N=19 (2.5%); APRI, N=21 (2.8%); NFS, N=62 (8.6%)] and exhibited sexual dimorphism with males having worse metabolic characteristics. NAFLD patients with normal ALT were more likely to be older, female, have a lower BMI, and have a higher prevalence of cirrhosis, DM, hypertension, hyperlipidemia, and renal dysfunction. Conclusion: Patients with NAFLD have metabolic characteristics associated with several comorbidities, including NAFLD patients with normal ALT. Mechanistic studies are needed to examine and analyze complex, interactive effects between sex, age, and other factors that may accelerate NAFLD disease progression.