Bovenzi Massimo, Prodi Andrea, Mauro Marcella
Clinical Unit of Occupational Medicine, Department of Medical Sciences, University of Trieste, Centro Tumori, Via della Pietà 19, I-34129 Trieste, Italy.
Scand J Work Environ Health. 2015 May 1;41(3):247-58. doi: 10.5271/sjweh.3490. Epub 2015 Mar 16.
This cohort study aims to compare the performance of alternative frequency weightings of hand-transmitted vibration (HTV) for the assessment of the exposure-response relationships for neurosensory disorders and reduced work ability among HTV-exposed workers.
In a 3-year follow up study, the occurrence of neurosensory symptoms and reduced work ability, and the response to quantitative sensory testing (grip force, manipulative dexterity, touch sensation) were investigated in 249 HTV-exposed workers and 138 healthy controls. Among the HTV-exposed workers, the sensory outcomes were related to measures of daily vibration exposure expressed in terms of 8-hour energy-equivalent frequency-weighted acceleration magnitude [A(8)]. To calculate A(8), the acceleration magnitudes of vibration were weighted by means of four alternative frequency weightings of HTV.
The occurrence of neurosensory symptoms, reduced work ability, and abnormalities of sensory tests was greater among the HTV-exposed workers than the controls. Among the HTV-exposed workers, the deterioration of neurosensory outcomes and the reduction of work ability increased on par with the measures of vibration exposure. Exposure-response models revealed that the four alternative frequency weightings of HTV provided the same predictions for the probability of finger numbness among the exposed workers (observed 36% versus predicted 32%).
The findings of this study revealed significant dose-response relationships between measures of vibration exposure, sensory disorders, and reduced work ability among the HTV-exposed workers. There were no differences in the prediction of finger numbness between measures of vibration exposure calculated with alternative frequency weightings of HTV.
本队列研究旨在比较手部传递振动（HTV）的替代频率加权法在评估HTV暴露工人神经感觉障碍和工作能力下降的暴露-反应关系方面的表现。
在一项为期3年的随访研究中，对249名HTV暴露工人和138名健康对照者进行了神经感觉症状的发生情况、工作能力下降情况以及对定量感觉测试（握力、操作灵活性、触觉）的反应的调查。在HTV暴露工人中，感觉结果与以8小时能量等效频率加权加速度幅值[A(8)]表示的每日振动暴露量度相关。为了计算A(8)，振动的加速度幅值通过HTV的四种替代频率加权法进行加权。
HTV暴露工人中神经感觉症状的发生、工作能力下降以及感觉测试异常情况均比对照组更严重。在HTV暴露工人中，神经感觉结果的恶化和工作能力的下降与振动暴露量度呈同等程度的增加。暴露-反应模型显示，HTV的四种替代频率加权法对暴露工人手指麻木的概率提供了相同的预测（观察到的为36%，预测的为32%）。
本研究结果揭示了HTV暴露工人的振动暴露量度、感觉障碍和工作能力下降之间存在显著的剂量-反应关系。使用HTV替代频率加权法计算的振动暴露量度在预测手指麻木方面没有差异。
