Department of Internal Medicine.
Department of Gastroenterology and Hepatology.
Eur J Gastroenterol Hepatol. 2021 May 1;33(5):745-751. doi: 10.1097/MEG.0000000000001967.
Nonalcoholic fatty liver disease (NAFLD) and impaired lung function share similar risk factors and phenotypes, such as obesity and type 2 diabetes. The study is an updated meta-analysis to evaluate the association between NAFLD and impaired lung function.
A total of 696 articles were identified with mention of NAFLD and lung function (or pulmonary function testing) in MEDLINE, EMBASE, and Scopus. After de-duplication, 455 articles were screened, 18 underwent full-text review. Five studies met our review and inclusion criteria with an interrater reliability kappa score of 1.
Five studies with a total of 118 118 subjects (28.4% with NAFLD) were included. The cross-sectional studies supported a statistically significant relationship between decreased pulmonary function tests and NAFLD. There was no association observed with obstructive lung pattern. One of the longitudinal studies revealed an association with increased rate of decline in forced vital capacity in patients with NAFLD and FIB4 score ≥1.30 (-21.7 vs. -27.4 mL/year, P = 0.001 in males, -22.4 vs. -27.9 mL/year, P = 0.016 in females). The second longitudinal study revealed that patients with impaired pulmonary function had an increased hazard ratio of developing NAFLD dependent on the severity of pulmonary impairment.
This is the first systematic review that supports an association of NAFLD with decreased (restrictive) lung function. The estimated severity of liver fibrosis correlates with the rate of progression of restrictive lung function. There are also data showing that patients with impaired lung function have a higher risk of developing NAFLD.
非酒精性脂肪性肝病（NAFLD）和肺功能受损具有相似的风险因素和表型，如肥胖和 2 型糖尿病。本研究是一项更新的荟萃分析，旨在评估 NAFLD 与肺功能受损之间的关系。
通过 MEDLINE、EMBASE 和 Scopus 共检索到 696 篇提到 NAFLD 和肺功能（或肺功能测试）的文章。去重后，筛选出 455 篇文章，其中 18 篇进行了全文审查。有 5 项研究符合我们的综述和纳入标准，组内一致性kappa 值为 1。
共有 5 项研究纳入 118118 例受试者（28.4%患有 NAFLD）。横断面研究支持肺功能测试下降与 NAFLD 之间存在统计学显著关联。但未观察到与阻塞性肺模式有关联。其中一项纵向研究显示，在 FIB4 评分≥1.30 的 NAFLD 患者中，用力肺活量的下降率增加（男性为-21.7 与-27.4 mL/年，P=0.001；女性为-22.4 与-27.9 mL/年，P=0.016）。第二项纵向研究显示，肺功能受损患者发生 NAFLD 的风险比随着肺损伤严重程度的增加而增加。
这是第一项支持 NAFLD 与肺功能下降（限制性）相关的系统评价。估计的肝纤维化严重程度与限制性肺功能进展的速度相关。还有数据表明，肺功能受损的患者发生 NAFLD 的风险更高。
