Relationships of neurosensory disorders and reduced work ability to alternative frequency weightings of hand-transmitted vibration
本研究追踪249名手传振动暴露工人和138名健康对照者3年，发现振动暴露与神经感觉症状、工作能力下降及感觉测试异常存在剂量反应关系，且四种频率加权对指麻木的预测效果相同。
OBJECTIVE: 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. METHODS: 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. RESULTS: 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%). CONCLUSIONS: 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.