Prospective Cohort Study of Work Functioning Impairment and Subsequent Absenteeism Among Japanese Workers.

OBJECTIVE: This study examined the association of work functioning impairment as measured by work functioning impairment scale (WFun) and subsequent sick leave. METHODS: A prospective cohort study was conducted at a manufacturer in Japan, and 1263 employees participated. Information on sick leave was gathered during an 18-month follow-up period. RESULTS: The hazard ratios (HRs) of long-term sick leave were substantially increased for those with a WFun score greater than 25 (HR = 3.99, P = 0.003). The incidence rate ratios (IRRs) of days of short-term absence gradually increased as scores of WFun increased (IRR = 1.18, P < 0.001 in the subjects with WFun of over 25 comparing with those with WFun of 14 or less). CONCLUSIONS: Assessing work functioning impairment is a useful way of classifying risk for future sick leave among employees.

[Comparison of Work Ability Index and cognitive function tests].

The purpose of this study was to evaluate the effect of aging with regard to scores for certain cognitive function tests and WAI (Work Ability Index), and to examine the relationship between cognitive function test scores and work ability as measured by WAI. The subjects were 139 male employees of a factory producing steel plate, and their average age was 48.1 yr (SD 16.4). The WAI and cognitive function tests were conducted and valid scores were obtained from 134 subjects as to WAI, and from 88 subjects as to cognitive function tests. The subjects were divided into two groups: young workers (under 45 yr) and middle-aged to elderly workers (45 yr and over). The WAI scores of the two groups were compared, but no significant differences were observed. Nevertheless, for two WAI items, WAI-2 and WAI-7, the scores of the middle-aged to elderly worker group were significantly higher than those of the young worker group. In contrast, the scores for WAI-3 of the middle-aged to elderly group were significantly lower than those of the young worker group. The cognitive function test scores for the two groups were also compared. The scores for Working Memory test, Tracking test, and Sentence-to-sentence Comparison test of the middle-aged to elderly worker group were significantly lower than those of the younger group. Moreover, for the middle-aged to elderly worker group, the average WAI-3 scores for those with good cognitive function test results and those with poor cognitive function test results were compared, but there were no significant differences. This result shows that deterioration of physical function caused by aging is not related to deterioration of cognitive function caused by aging in the subjects of this study. The reason for this may be that the subjects are blue-collar workers, and thus cognitive functions are less important for their work.

[Association of working postures and some lifestyles with low back pain in a manufactory].

The aim of this study was to determine the relationship between work and low back pain (LBP) by examining both working postures and the workers' everyday lifestyle. Subjects were 118 male workers in a small-to-medium-sized factory having three kinds of workplaces: the slit line, the packing line, and the crane unit. Working posture analysis with OWAS and interviews were carried out. The result of posture analysis showed that the standing posture with both legs straight and back bent appeared most frequently in all three workplaces. Meanwhile, the prevalence of LBP was almost equal among these groups, with 70% of workers having experienced LBP in each group. But the main cause of LBP differed among the three groups. On the slit line, the result of regression analysis and interview suggested that exercises in the past affected the prevalence of LBP, and that aging and work made LBP worse. On the packing line, many workers were transferred to other positions after a few years, and thus might affect the prevalence of LBP in other workplaces. For the crane unit, it appeared that work in previous positions might affect the occurrence of LBP. Moreover, it seemed that activities in the workplace, rather than lifestyles, contribute to the occurrence of LBP in this factory.