Non-alcoholic fatty liver disease and type 2 diabetes: Importance of glycemic control

Non-alcoholic fatty liver disease, metabolic goal achievement with incident cardiovascular disease and eGFR-based chronic kidney disease in patients with prediabetes and diabetes

AIMS/HYPOTHESIS

We aimed to evaluate the effect of NAFLD on the risk of incident cardiovascular disease (CVD) and estimated glomerular filtration rate (eGFR)-based chronic kidney disease (CKD), and further test the joint effects and interactions between NAFLD status and individual metabolic element, as well as the total 'ABCs' metabolic goal achievement, on the CVD and CKD risk among 101,296 patients with prediabetes or diabetes from a prospective cohort study.

METHODS

We conducted the study based on the China Cardiometabolic Disease and Cancer Cohort (4C) study, a large-scale, population-based prospective cohort. After excluding alcohol abuse and other cause of hepatic diseases, we used fatty liver index (FLI) ≥ 60 as a proxy of NAFLD and stratified the probability of fibrosis by aspartate transaminase/alanine transaminase ratio (AAR) with cut-offs of 0.8 and 1.4. 'ABCs' metabolic goal was defined as subjects who had HbA1c < 6.5% (A), SBP/DBP < 130/80 mmHg (B), and LDL-C < 100 mg/dL (C). During 3.8 years follow-up, we validated 2340 CVD events based on medical records and identified 1943 participants developed CKD based on centrally tested eGFR.

RESULTS

The multivariable adjusted hazard ratios (HRs) were 1.15 (95% confidence interval (CI), 1.05-1.27) for CVD events and 1.33 (95% CI, 1.20-1.48) for CKD among NAFLD patients, compared with participants without NAFLD. Of NAFLD patients, relative to individuals with low AAR (<0.8), those with high AAR (≥1.4) were more likely to experience CVD events [1.62 (1.21-2.18)] and CKD [1.63 (1.17-2.28)]. Participants with NAFLD and comorbid poorly controlled metabolic risk factors had higher risk of CVD events or CKD than having either alone, with a significant interaction between poor glycemic control and NAFLD on the risk of vascular complications.

CONCLUSIONS

NAFLD was associated with incident CVD and CKD among patients with prediabetes or diabetes. Such associations were substantially modified by the comprehensive achievement of metabolic goal.

Nonalcoholic Fatty Liver Disease: An Important Consideration for Primary Care Providers in Hawai'i

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. NAFLD is a broad term for both non-alcoholic fatty liver (NAFL), which describes simple fatty liver without inflammation, and non-alcoholic steatohepatitis (NASH), the more severe phenotype with hepatocellular inflammation. The population of Hawai'i is particularly vulnerable to the NAFLD and obesity epidemics due to its large proportions of high-risk ethnic minorities exposed to varying degrees of westernization. Unfortunately, primary care providers (PCPs) often face a lack of awareness on the diagnosis and disease spectrum of NAFLD. Early initiation of treatment for NAFLD is crucial to slow its progression and prevent liver-related morbidity and mortality. This review aims to raise awareness for NAFLD among PCPs in Hawai'i by summarizing the disease's epidemiology, diagnosis, and treatment. The diagnostic workup of NAFLD in the primary care setting involves exclusion of other liver disease etiologies and staging assessment of fibrosis and steatosis through non-invasive means such as serum biomarkers or elastography. Patients with overt signs and symptoms of cirrhosis or a high likelihood of advanced hepatic fibrosis should be referred to liver disease specialists. The role of PCPs in NAFLD management involves facilitating weight loss through therapeutic lifestyle modifications and treatment of comorbid cardiovascular conditions. Evidence-based pharmacologic therapies for NAFLD are available, such as vitamin E and pioglitazone, with more currently in development.