Institute of Medical Research A. Lanari, University of Buenos Aires, Buenos Aires, Argentina.
Department of Clinical and Molecular Hepatology, Institute of Medical Research (IDIM), National Scientific and Technical Research Council (CONICET)-University of Buenos Aires, Buenos Aires, Argentina.
Aliment Pharmacol Ther. 2018 Jan;47(1):16-25. doi: 10.1111/apt.14401. Epub 2017 Oct 30.
Current evidence suggests that lean and obese patients with nonalcoholic fatty liver disease (NAFLD) share an altered metabolic and cardiovascular profile. However, there is an incomplete understanding of the natural history of "lean-NAFLD." Indeed, an unanswered question is whether lean (BMI ≤ 25 Kg/m ) NAFLD-patients are protected from severe histological outcomes.
To perform a meta-analysis with the goal of providing a quantitative estimation of the magnitude of fibrosis, as well as histological features associated with the disease severity, in lean versus overweight/obese-NAFLD patients.
Through a systematic search up to July 2017, we identified eight studies that compared histological outcomes in lean (n = 493) versus overweight/obese (n = 2209) patients.
Relative to lean-NAFLD, overweight/obese-NAFLD patients showed significantly (P = .032) higher fibrosis scores; the observed difference in means between the two groups, which is the absolute difference between the mean value of fibrosis score [0-4] ± standard error, was 0.28 ± 0.13. The risk of having nonalcoholic steatohepatitis-NASH (OR 0.58 95% CI 0.34-0.97) was significantly lower in lean-NAFLD (n = 322) than in overweight/obese-NAFLD (n = 1357), P = .04. Relative to lean-NAFLD, overweight/obese-NAFLD patients also have significantly greater NAFLD activity (difference in means ± SE: 0.58 ± 0.16, P = .0004) and steatosis (difference in means ± SE: 0.23 ± 0.07, P = .002) scores.
Lean-NAFLD patients tend to show less severe histological features as compared to overweight/obese-NAFLD patients. Subsequent longitudinal assessment is needed to understand the clinical impact of these findings; however, the significant ~ 25% increment of mean fibrosis score in overweight/obese patients suggests that obesity could predict a worse long-term prognosis.
目前的证据表明，非酒精性脂肪性肝病（NAFLD）的瘦型和肥胖型患者具有改变的代谢和心血管特征。然而，人们对“瘦型 NAFLD”的自然病史仍不完全了解。实际上，一个悬而未决的问题是，瘦型（BMI≤25kg/m2）NAFLD 患者是否免受严重的组织学结局影响。
进行荟萃分析，旨在提供量化估计，比较瘦型（n=493）与超重/肥胖型（n=2209）NAFLD 患者的纤维化程度以及与疾病严重程度相关的组织学特征。
通过系统检索，截至 2017 年 7 月，我们共确定了 8 项比较瘦型（n=493）与超重/肥胖型（n=2209）患者组织学结果的研究。
与瘦型 NAFLD 相比，超重/肥胖型 NAFLD 患者的纤维化评分显著升高（P=0.032）；两组之间观察到的平均差异（两组纤维化评分均值的绝对差值，即 [0-4]±标准误差）为 0.28±0.13。与超重/肥胖型 NAFLD 相比，瘦型 NAFLD（n=322）患者发生非酒精性脂肪性肝炎-NASH（OR 0.58，95%CI 0.34-0.97）的风险显著降低（P=0.04）。与瘦型 NAFLD 相比，超重/肥胖型 NAFLD 患者的 NAFLD 活动度（均值差异±SE：0.58±0.16，P=0.0004）和脂肪变性（均值差异±SE：0.23±0.07，P=0.002）评分也显著升高。
与超重/肥胖型 NAFLD 患者相比，瘦型 NAFLD 患者的组织学特征往往较轻。需要进行后续的纵向评估，以了解这些发现的临床意义；然而，超重/肥胖患者的平均纤维化评分显著增加约 25%，这表明肥胖可能预示着更差的长期预后。
