Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine and School of Medicine, Seoul, South Korea.
Front Endocrinol (Lausanne). 2021 May 6;12:647459. doi: 10.3389/fendo.2021.647459. eCollection 2021.
The global incidence of NAFLD is rising sharply due to various risk factors. As previous studies reported adverse health impact of long working hours on metabolic diseases, such as diabetes mellitus and obesity, it is plausible that NAFLD is also associated with working excessive hours. However, data regarding this issue is limited.
In this cross-sectional study based on Korea National Health and Nutrition Examination Survey VII, 5,661 working adults without previous liver disease or heavy alcohol drinking habits were included. The subjects were categorized into three groups according to working hours: 36-42, 43-52, and 53-83 hours/week. NAFLD was defined using the hepatic steatosis index (HSI), which is a validated prediction model for determining NAFLD.
The prevalence of NAFLD (HSI ≥36) increased with longer working hours: 23.0%, 25.6%, and 30.6% in the 36-42, 43-52, and 53-83 hours/week group, respectively (p <0.001). Subjects who worked 53-83 hours/week had higher odds for NAFLD than those who worked the standard 36-42 hours/week (OR 1.23, 95% CI 1.02-1.50, p = 0.033) after adjusting for age, sex, body mass index, smoking, alcohol, exercise, diabetes mellitus, hypertension, serum triglyceride, and total cholesterol. This association was consistent across subgroups according to working schedule (daytime shift workers) or occupation type (office manual workers). In particular, the relationship between long working hours and NAFLD was pronounced in workers aged <60 years and in female workers.
Long working hours was significantly associated with NAFLD. Further prospective studies are required to validate this finding with causal relationship.
由于各种风险因素，非酒精性脂肪性肝病（NAFLD）的全球发病率正在急剧上升。由于先前的研究报告称长时间工作对代谢疾病（如糖尿病和肥胖症）有不良健康影响，因此可以推测 NAFLD 也与工作时间过长有关。然而，关于这个问题的数据是有限的。
在这项基于韩国国家健康和营养检查调查 VII 的横断面研究中，纳入了 5661 名没有既往肝脏疾病或大量饮酒习惯的在职成年人。根据工作时间将受试者分为三组：36-42 小时/周、43-52 小时/周和 53-83 小时/周。NAFLD 使用肝脂肪变性指数（HSI）定义，这是一种用于确定 NAFLD 的经过验证的预测模型。
随着工作时间的延长，NAFLD（HSI≥36）的患病率增加：36-42 小时/周、43-52 小时/周和 53-83 小时/周组的患病率分别为 23.0%、25.6%和 30.6%（p<0.001）。在校正年龄、性别、体重指数、吸烟、饮酒、运动、糖尿病、高血压、血清甘油三酯和总胆固醇后，每周工作 53-83 小时的受试者患 NAFLD 的可能性高于每周工作 36-42 小时的受试者（OR 1.23，95%CI 1.02-1.50，p=0.033）。这种关联在根据工作时间表（轮班制工人）或职业类型（办公室体力劳动者）划分的亚组中是一致的。特别是，在年龄<60 岁和女性劳动者中，长时间工作与 NAFLD 之间的关系更为显著。
长时间工作与 NAFLD 显著相关。需要进一步的前瞻性研究来验证这种关联的因果关系。
