Pulmonary impairment in a cotton textile factory in Nigeria: is lifetime alcohol intake with low cigarette smoking a confounding factor?

Abstract

A study of 60 Nigerian workers who seldom smoked and who were exposed for 2-15 yr in the printing, dyeing, and maintenance sections of a cotton textile factory showed a 38% airway and 20% "probably airway" symptoms. The airway symptoms were significantly (p less than .005) associated with a decrement in spirometric lung function before and after adjustment for age, height, and duration of employment. The change in residual pulmonary function (PFT) per year of employment was three times higher for the subjects with airway symptoms than for subjects presenting no symptoms. Lifetime alcohol intake was significantly (.025 greater than p less than .01) negatively correlated with pulmonary function and obstructive and restrictive lung disease parameters. Together with body weight, alcohol bottle-years accounted for between 18 and 22% of the variation in lung function, in a forward and reverse stepwise regression analysis. When duration of employment was standardized, subjects with considerable alcohol intake had significantly (.025 greater than p less than .005) lower pulmonary function before and after adjustment for age and height. When the residual PFT was further adjusted for duration of employment, the subjects with higher alcohol intake had significantly (.01 greater than p less than .005) higher residual per year of employment. The subjects presenting airway symptoms had significantly (.05 greater than p less than .005) higher alcohol intake than those in other symptom categories. These data suggest that alcohol intake is a probable confounder in the observed airway and PFT changes.