Am. J. Respir. Crit. Care Med., Vol 150, No. 1, Jul 1994, 59-65.
Respiratory health among retired grain elevator workers
SM Kennedy, H Dimich-Ward, A Desjardins, A Kassam, S Vedal and M Chan-Yeung
Department of Medicine, University of British Columbia, Vancouver, Canada.
Previous studies of grain elevator workers have shown exposure-related
increased rates for respiratory symptoms and reduced levels of lung
function compared with those of other employed populations. However, some
reports have suggested that this effect may be reversible after cessation
of exposure. To investigate this, we conducted a respiratory health survey
among 75 retired grain elevator workers and 37 retired civic workers.
Methods included a standard respiratory questionnaire, routine spirometry,
chest radiography, a 6-min walk test, and a specialized questionnaire to
assess the impact of breathing trouble on the activities of daily life.
Grain retirees were slightly older than civic retirees (69 versus 67 yr, p
< 0.05) and less likely to be atopic (7 versus 35%, p < 0.01). Grain
elevator retirees reported more dyspnea (44 versus 11%, p < 0.01) and
had significantly lower levels for both FEV1 (78.6 versus 88.2% pred) and
FVC (90.0 versus 97.7% pred) (both p < 0.05). Compared with civic
retirees, grain retirees reported the same average level of breathlessness
after the 6-min walk test, but they walked a significantly shorter distance
(p < 0.01); they also scored higher on the impairment of activities
scale and had a greater proportion of persons reporting impairment of daily
activities caused by breathing trouble (p < 0.05). Comparison of the
changes in lung function from 1975 to the present study (i.e., from active
employment to retirement) showed that grain workers had consistently lower
levels of lung function than did civic workers while still employed, with
no reversibility after retirement.(ABSTRACT TRUNCATED AT 250 WORDS)
