Department of Occupational and Environmental Medicine, Sahlgrenska Academy, University of Gothenburg, Medicinaregatan 16, Po 414, SE-405 30 Gothenburg, Sweden.
Scand J Work Environ Health. 2014 Mar;40(2):203-9. doi: 10.5271/sjweh.3386. Epub 2013 Sep 25.
The aim of this study was to investigate the exposure-response relationship of hand-arm vibration exposure to neurological symptoms (numbness) of the hand in a cohort of vibration-exposed workers.
The baseline cohort comprised 241 office and manual workers with and without exposure to hand-arm vibration. Numbness (the symptom or event) in the hand was assessed for all subjects at baseline and follow-ups after 5, 10, and 16 years. The workers were stratified into quartiles with no exposure in the first quartile and increasing intensity of exposure in quartiles 2-4 (groups 1-3). Data analysis was performed using survival analysis (time to event). Information on cumulative exposure and years of exposure to event was collected via questionnaires. Measurements were performed in accordance with the International Organization for Standardization (ISO) 5349-1.
The hazard ratio (HR) of risk of event (numbness) differed statistically significantly between the non-exposed group (group 0) and the two higher exposure groups (groups 2 and 3). There was also a significant ratio difference between the lowest exposure group (group 1) and the two higher groups. The ratio for group 1 was 1.77 [95% confidence interval (95% CI) 0.96-3.26] compared with 3.78 (95% CI 2.15-6.62) and 5.31 (95% CI 3.06-9.20) for groups 2 and 3, respectively.
The results suggest a dose-response relationship between vibration exposure and numbness of the hands. This underlines the importance of keeping vibration levels low to prevent neurological injury to the hands.
本研究旨在调查手臂振动暴露与手部神经症状（麻木）之间的暴露-反应关系。
本研究的基线队列包括 241 名接触和不接触手臂振动的办公室和体力劳动者。所有研究对象在基线以及 5、10 和 16 年随访时均评估手部麻木（症状或事件）。将工人按 quartiles 分层，第 1 quartiles 为无暴露，第 2-4 quartiles 为接触强度递增（分为组 1-3）。采用生存分析（事件时间）进行数据分析。通过问卷调查收集累积暴露量和暴露于事件的年数。测量按照国际标准化组织（ISO）5349-1 进行。
在非暴露组（组 0）和两个较高暴露组（组 2 和 3）之间，事件（麻木）的风险比（HR）有统计学显著差异。在最低暴露组（组 1）和两个较高组之间也存在显著的比值差异。组 1 的比值为 1.77 [95%置信区间（95% CI）0.96-3.26]，而组 2 和 3 的比值分别为 3.78（95% CI 2.15-6.62）和 5.31（95% CI 3.06-9.20）。
结果表明，振动暴露与手部麻木之间存在剂量-反应关系。这强调了保持低振动水平以防止手部神经损伤的重要性。
