Corporate Environmental Safety Health and Quality Assurance, Asahi Kasei Corporation, Tokyo, Japan.
Scand J Work Environ Health. 2012 Jul;38(4):337-42. doi: 10.5271/sjweh.3297. Epub 2012 Apr 16.
The aim of this study was to investigate the effect of shift working on the risk of developing impaired glucose tolerance (IGT).
This study comprised 6413 male employees (5608 daytime workers, 512 3-shift workers and 293 2-shift workers) whose work schedules remained constant during the follow-up period (mean follow-up period 9.9 years). IGT was defined as Hemoglobin A1c ≥ 5.9%. The Cox proportional hazards model was used to estimate the risk of developing IGT, after making adjustments for age, smoking, alcohol consumption, leisure-time physical activity, body mass index (BMI) and Hemoglobin A1c (HbA1c) at baseline. Analysis was additionally performed for a sub-cohort of 1625 workers with BMI of 20.0-25.0 kg/m² that did not change by >2.0 kg/m² during the follow up period.
The risk of developing IGT was significantly elevated among both 3-shift workers [hazard ratio (HR) 1.78, 95% confidence interval (95% CI) 1.49- 2.14] and 2-shift workers (HR 2.62, 95% CI 2.17-3.17). Significant elevations of the risk were still observed at the additional analysis on the sub-cohort (3-shift work: HR 3.55, 95% CI 2.02-6.25; 2-shift work: HR 4.86, 95% CI 2.62-9.01).
Both 2- and 3-shift workers were associated with a high risk factor of developing IGT compared to day workers. Moreover, 2-shift workers had a higher risk than 3-shift workers. The risk was observed even among workers whose body mass remained within the normal range.
本研究旨在探讨轮班工作对发展为葡萄糖耐量受损（IGT）的风险的影响。
这项研究包括 6413 名男性员工（5608 名白班工人、512 名三班倒工人和 293 名两班倒工人），在随访期间（平均随访时间为 9.9 年）他们的工作时间表保持不变。IGT 定义为血红蛋白 A1c≥5.9%。使用 Cox 比例风险模型，在调整年龄、吸烟、饮酒、休闲时间体力活动、体重指数（BMI）和基线时的血红蛋白 A1c（HbA1c）后，估计发展为 IGT 的风险。此外，还对 1625 名 BMI 为 20.0-25.0kg/m²且在随访期间体重变化不超过 2.0kg/m²的工人亚组进行了分析。
三班倒工人（危险比 [HR]1.78，95%置信区间 [95%CI]1.49-2.14）和两班倒工人（HR2.62，95%CI2.17-3.17）发展为 IGT 的风险显著升高。在对亚组的额外分析中，仍观察到风险显著升高（三班倒工作：HR3.55，95%CI2.02-6.25；两班倒工作：HR4.86，95%CI2.62-9.01）。
与白班工人相比，两班倒和三班倒工人发展为 IGT 的风险因素较高。此外，两班倒工人的风险高于三班倒工人。即使在体重保持在正常范围内的工人中，也观察到了这种风险。
