[Analyses of work-relatedness of health problems among truck drivers by questionnaire survey]

In order to estimate occupational risk factors for health problems among truck drivers, a questionnaire survey of working conditions, job content in truck transportation, subjective symptoms and present illnesses was carried out among 541 truck transportation workers in 1997. The valid response rate was 85.7%, and 134 local truck drivers, 199 long-distance truck drivers and 71 clerical workers were analyzed. First, to examine occupational risk factors and health problems among the three groups, the authors analyzed working conditions, job content in truck transportation, subjective symptoms and present illnesses. Second, to estimate the work-relatedness of health problems among local truck drivers and long-distance truck drivers, logistic regression analyses were conducted, and odds ratios and 95% confidence intervals were computed. The prevalence rates of working factors affecting health problems of truck drivers were significantly higher than those of clerical workers in the items on irregular shift work, working environment, working posture, handling heavy materials, job stress due to overloading and long working time and limited time off. The prevalence rates for subjective symptoms (ringing in the ears, neck pain and low back pain) and present illnesses (hypertension, ulcers in the digestive tract, back injuries, whiplash injuries and hemorrhoids) among truck drivers were significantly higher than those of clerical workers. In logistic regression analyses, many work-related items except age, BMI and smoking habit showed significantly higher odds ratios for subjective symptoms and present illnesses of truck drivers. Odds ratios for hypertension, heart diseases and related subjective symptoms among local truck drivers were significantly increased by job career, twisting posture, vibration and driving stress. Odds ratios for gastro-duodenal diseases and related subjective symptoms were significantly increased by narrow working space, sleeping in the truck, driving distance, squatting posture and driving stress. Odds ratios for ringing in the ears among local truck drivers were significantly increased by job career, long working time, narrow working space, sleeping in the truck and driving stress. Odds ratios for musculo-skeletal diseases and related subjective symptoms were significantly increased by overwork, vibration, narrow working space, sitting posture and shortage of recess. Odds ratios for fatigue symptoms were significantly increased by the shortage of recess, vibration and driving stress. In order to cope with the health problems of truck drivers, it is recommended that working conditions and work loads for among truck drivers as described above be improved.