Combined Effect of Grain Farming and Smoking on Lung Function and the Prevalence of Chronic Bronchitis

Abstract

The combined effect of grain farming and smoking on lung function and the prevalence of chronic bronchitis was examined in 1633 residents 20 to 65 years of age from the town of Humboldt, Saskatchewan. Multiple multivariate analysis indicated that in women grain farming and smoking had a significant synergistic effect on the values of forced expired volume in one second/forced vital capacity (FEV1/FVC), mid-expiratory flow rate (MMFR), flow rate at 50% and 25% of total volume (Vmax50 and Vmax25) after adjustment for covariates including age and height. No other factors were found to change the results. The combined effect of grain farming and smoking on lung function was not statistically significant in men. The data also show that female non-smoking grain farmers had an identical prevalence of chronic bronchitis compared with non-smoking female non-farmers, 2.0% versus 2.1%. But in women with a positive smoking history, the prevalence was 13.2% and 5.9% respectively, giving an adjusted odds ratio in grain farmers compared to non-farmers of 3.55 (95% confidence interval (Cl): 1.06-11.30). It was found that the prevalence of chronic bronchitis increased more rapidly with increasing cigarette consumption in grain farmers than in non-farmers in women. It was estimated that 85%, 72% and 66% of the prevalence of chronic bronchitis was attributed to the joint effects of grain farming and ex-smoking, light smoking (1-19 cigarettes/day) or heavy smoking (20+ cigarettes/day) status, respectively. In contrast to women, the effect of grain farming on the prevalence of chronic bronchitis was similar in men with and without a positive smoking history. Our data suggest that there is a positive interactive effect of grain farming exposure and smoking on lung function and the prevalence of chronic bronchitis in women. The difference in the interaction between men and women requires further study.

Chronic bronchitis among French adults: high prevalence and underdiagnosis

“…Daily cigarette consumption was highest among patients with CB. Neither occupation nor the place of living had detectable effects on the rate of CB, despite studies that have shown that some occupations increase the prevalence of CB [24][25][26][27][28][29][30][31], and other studies that have demonstrated differences in CB prevalence among geographical areas [32,33]. The present survey found differences only in CC and CE among people living either in the east of France or in Ile-de France.…”

Sex-related interactive effect of smoking and household pets on asthma incidence

“…Chronic exposure to grain dust and cigarette smoking are both associated with chronic airways disease. CHEN et al [28] reported an interactive effect between grain farming exposure and smoking on lung function and chronic bronchitis in females but not males. Heavy cigarette smokers have been reported to have a higher rate of emergency department visits for respiratory disease following days of high ozone levels compared with nonsmokers [29].…”

Effect of Particle Size on Respiratory Protection Provided by Two Types of N95 Respirators Used in Agricultural Settings

“…Several studies have shown that farmers growing different types of grain and soybeans (1,2) and farmers raising livestock (3) have respiratory symptoms and diseases. This may have considerable impact worldwide considering there are approximately 3 million farm workers in the United States alone.…”