Zheng Jia-Rui, Wang Zi-Long, Jiang Su-Zhen, Chen Hong-Song, Feng Bo
Peking University Hepatology Institute, Peking University People's Hospital, Beijing 100044, China.
World J Hepatol. 2023 Jun 27;15(6):813-825. doi: 10.4254/wjh.v15.i6.813.
Serum alanine aminotransferase (ALT) levels are often considered a marker to evaluate liver disease and its severity.
To investigate the association between ALT levels and all-cause and cause-specific mortality in patients with nonalcoholic fatty liver disease (NAFLD).
The Third National Health and Nutrition Examination Survey (NHANES-III) from 1988 to 1994 and NHANES-III-related mortality data from 2019 onward were used to obtain the necessary data for the study. NAFLD was defined as hepatic steatosis, as diagnosed by ultrasound, with no other liver diseases. ALT levels were categorized into four groups according to the different recommended upper limits of normal (ULN) in men and women: < 0.5 ULN, 0.5-1 ULN, 1-2 ULN, and ≥ 2 ULN. The hazard ratios for all-cause mortality and cause-specific mortality were analyzed using the Cox proportional hazard model.
Multivariate logistic regression analysis demonstrated that the odds ratio of NAFLD correlated positively with increased serum ALT levels. In patients with NAFLD, all-cause mortality and cardiovascular mortality were the highest when ALT was < 0.5 ULN, yet cancer-related mortality was the highest when ALT was ≥ 2 ULN. The same results could be found in both men and women. Univariate analysis showed that severe NAFLD with normal ALT levels had the highest all-cause and cause-specific mortality, but the difference was not statistically significant after adjustment for age and multivariate factors.
The risk of NAFLD was positively correlated with ALT level, but all-cause and cardiovascular mortality were the highest when ALT was < 0.5 ULN. Regardless of the severity of NAFLD, normal or lower ALT levels were associated with higher mortality than elevated ALT levels. Clinicians should be aware that high ALT levels indicate liver injury, but low ALT levels are associated with a higher risk of death.
血清丙氨酸氨基转移酶（ALT）水平常被视为评估肝脏疾病及其严重程度的标志物。
探讨非酒精性脂肪性肝病（NAFLD）患者ALT水平与全因死亡率及特定病因死亡率之间的关联。
使用1988年至1994年的第三次全国健康和营养检查调查（NHANES - III）以及2019年起的NHANES - III相关死亡率数据来获取本研究所需数据。NAFLD定义为经超声诊断的肝脂肪变性，且无其他肝脏疾病。根据男性和女性不同的推荐正常上限（ULN），将ALT水平分为四组：<0.5 ULN、0.5 - 1 ULN、1 - 2 ULN和≥2 ULN。使用Cox比例风险模型分析全因死亡率和特定病因死亡率的风险比。
多因素逻辑回归分析表明，NAFLD的比值比与血清ALT水平升高呈正相关。在NAFLD患者中，当ALT <0.5 ULN时，全因死亡率和心血管死亡率最高，而当ALT≥2 ULN时，癌症相关死亡率最高。男性和女性均得到相同结果。单因素分析显示，ALT水平正常的重度NAFLD全因死亡率和特定病因死亡率最高，但在调整年龄和多因素后差异无统计学意义。
NAFLD风险与ALT水平呈正相关，但当ALT <0.5 ULN时全因死亡率和心血管死亡率最高。无论NAFLD的严重程度如何，正常或较低的ALT水平比升高的ALT水平与更高的死亡率相关。临床医生应意识到高ALT水平表明肝损伤，但低ALT水平与更高的死亡风险相关。
