Excess Longitudinal Decline in Lung Function in Grain Farmers

ABSTRACT

Workers in intensive agricultural operations are exposed to dust and endotoxin that are associated with respiratory effects. The authors investigated the longitudinal changes in lung function in male grain farmers. In this study, male grain farmers (n = 263) and male nonfarming control subjects (n = 261) studies initially in 1990/91 were followed-up in 1994/95 and 2003/04. After controlling for potential confounders, grain farmers had an excess annual decline of 9.2 ml/year (95% confidence interval [CI]: 2.7, 15.8, p = .006) in forced vital capacity (FVC) in comparison to control. Long-term exposure to grain dust and other substances in lifetime grain farmers results in progressive loss in lung function.

KEYWORDS:

• Decline in lung function
• grain farmers
• longitudinal study

This study was supported by grant MOP-57907 from the Canadian Institutes of Health Research. The research contained herein was conducted through the University of Saskatchewan.

The authors are grateful for the technical assistance of Nathalie Delmaire, RN, and Sandra Halliday, RN, for their roles in obtaining the data. The authors are also grateful to Ernie Barber, PhD, and Charles Rhodes, DVM, for their contributions to the 1990/91 and 1994/95 portions of the study, before going on to become Deans of the College of Agriculture and Western College of Veterinary Medicine, University of Saskatchewan, respectively. Finally, the authors are most appreciative of the assistance provided by the local rural hospitals in Saskatchewan that provided locations for all the studies and to the farmers and rural residents who contributed their interest and time over the 13 years of the project.