ABSTRACT
The pathophysiology and risk factors of nonalcoholic fatty liver disease (NAFLD) among lean patients is poorly understood and therefore investigated. We performed a meta-analysis of observational studies. Of 1175 articles found through searching from Medline/PubMed, Banglajol, and Google Scholar by two independent investigators, 22 were selected. Data from lean (n = 6768) and obese (n = 9253) patients with NAFLD were analyzed; lean (n = 43 398) and obese (n = 9619) subjects without NAFLD served as controls. Age, body mass index, waist circumference, systolic blood pressure, and diastolic blood pressure (DBP) had significantly higher estimates in lean NAFLD patients than in lean non-NAFLD controls. Fasting blood sugar [MD(mean difference) 5.17 mg/dl, 95% CI(confidence interval) 4.14-6.16], HbA1c [MD 0.29%, 95% CI 0.11-0.48], and insulin resistance [HOMA-IR] [MD 0.49 U, 95% CI 0.29-0.68]) were higher in lean NAFLD patients than in lean non-NAFLD controls. All components of the lipid profile were raised significantly in the former group except high-density lipoprotein. An increased uric acid (UA) level was found to be associated with the presence of NAFLD among lean. Cardio-metabolic profiles of nonlean NAFLD patients significantly differs from the counter group. However, the magnitude of the difference of lipid and glycemic profile barely reached statistical significance when subjects were grouped according to lean and nonlean NAFLD. But DBP (slope: 0.19, P < 0.037), HOMA-IR (slope: 0.58, P < 0.001), and UA (slope: 0.36, P = 0.022) were significantly higher if NAFLD was present compared to that of non-NAFLD group. Lean and nonlean NAFLD patients are metabolically similar and share common risk factors.
ABSTRACT
OBJECTIVES: Nonalcoholic Fatty Liver Disease (NAFLD) is thought to be a hepatic manifestation of Metabolic Syndrome (MS) or Insulin Resistance (IR). The aim of the study was to explore the clinical, anthropometric, metabolic, biochemical and histological profile of NAFLD patients without IR by comparing it with NAFLD with IR. METHODS: Total 851 patients with sonographic evidence of fatty liver were included. These patients underwent clinical, anthropometric, biochemical and histological evaluation. IR was calculated using the homeostatic model assessment. Liver biopsy done in 285 patients who consented for the procedure and who had MS or raised ALT. RESULTS: Among 851 NAFLD patients, 561(65.9%) patients were without IR and 290 (34.1%) patients were with IR. The proportion of male sex [230 (41.0%) vs. 89 (30.7%); P = 0.046] were higher but diabetes [19.10% vs. 39.0%; P = 0.000] and MS were [58.80%vs. 78.10%; P = 0.014] significantly lower in non IR group. Body Mass Index (BMI) kg/m2 and Waist Circumference (WC) in cm were also lower in non IR group: [26.6 ± 3.5 vs. 27.9 ± 4.3; P = 0.002] and [93.3 ± 8.4 vs. 95.9 ± 8.4; P = .003]. Lipid profile, ALT, AST and ALP were not differed between the groups. Histopathology reports revealed that lobular inflammation, ballooning and fibrosis were similar in two groups, only steatosis score was higher in IR group [2.0 ± 0.7 vs. 1.8 ± 0.8; P = 0.007]. CONCLUSION: There are significant proportion of NAFLD patients without IR in Bangladesh. NAFLD patients without IR predominantly male, had lower BMI, WC, MS and diabetes. Histologically NAFLD without IR equally severe with ballooning, lobular inflammation and fibrosis except steatosis. Insulin resistance is the principal but not the sole factor for NAFLD in our population.
