Lung function in relation to farm dwelling and farming activities in rural dwelling children

Background and objective: The relationship between farming exposures and pulmonary function in a rural paediatric population was evaluated. Methods: Baseline data collection records of the Saskatchewan Rural Health Study (SRHS), a population-based study, were used. A subset of children (6-14 years old) participated in clinical testing, including anthropometric measures and pulmonary function testing (PFT), using spirometry (n = 584). PFTs followed ATS criteria and all statistical analyses were controlled for age, sex and height. Results: Among clinical testing participants, 47.5% were females and 54.5% were farm dwelling. Of those living on farms, 77.5% were livestock farms. Mean percent predicted value (PPV) for forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) among children living on a farm were 104.8% and 105.4%, respectively. Mean PPV for FEV1 and FVC among children not living on a farm were 102.7% and 101.4%, respectively. After adjustment, higher FEV1 (= 0.079, SE = 0.033, P = 0.03) and FVC (= 0.110, SE = 0.039, P = 0.006) were seen among children living on a farm. A trend towards lower FEV1/FVC ratio (-0.013, SE = 0.008, P = 0.09) among children living on a farm was seen compared with children not living on a farm. Higher FVC and lower FEV1/FVC ratio were seen in children who regularly emptied grain bins (P < 0.05). Trends towards higher FEV1 (P = 0.14) and FVC (P = 0.08) were also seen with children living on a farm in the first year of life. Since the majority of the population was Caucasian (91%), the results were not race-corrected. Conclusion: We addressed the lack of knowledge regarding the association between lung function and rural exposures, and found that differences in lung function were seen between children living on a farm and not living on a farm in rural areas and certain farming activities, specifically emptying grain bins, where lung function was generally better in those living on a farm.