Chronic Respiratory Disease in Mining Communities in Marion County, West Virginia

Abstract

A study of respiratory disease has been carried out in five mining communities in Marion County, West Virginia, United States of America. Each of the five communities was defined by a private census. A questionnaire on respiratory symptoms, chest and other illnesses, smoking habits, and occupation was completed on all adults aged 20 years and over. All men aged 20-69 who lived in three of the towns were asked to attend at a centre for examination and 83% responded. The examination included the completion of a further questionnaire on respiratory symptoms, occupation, and smoking habits; examination of the chest; simple tests of ventilatory lung function; and a 14 × 17 in. postero-anterior radiograph of the chest. The prevalence of pneumoconiosis in these communities was low. In one of the three towns a pottery had operated intermittently in the past, giving rise to the possibility of pottery as well as mine dust exposure. Approximately 10-15% of miners and ex-miners aged 50-69 who had never worked in the pottery had category 1 or over pneumoconiosis. Only four cases of progressive massive fibrosis were found in this group, all in men aged 60 years and over. Pneumoconiosis was diagnosed only in men who had worked for 20 years or more underground. Among a group of potters who had never worked in mining the prevalence of pneumoconiosis was higher than in the miners and ex-miners, 27% in the 50-59 age group and 18% in the 60-69 age group being affected. The prevalence of symptoms was not appreciably higher in the miners and the ex-miners than in the non-miners except in the oldest decennial group where a somewhat higher prevalence of cough, breathlessness, and chest illness was noted. A significantly lower average forced expiratory volume in one second (F.E.V._1·0) was also found in this group. A higher prevalence of breathlessness, chest illness, and chronic bronchitis was found in non-miners who had worked in the pottery, and this increased prevalence was associated with a lower mean F.E.V._1·0. Smokers recorded a higher prevalence of symptoms, particularly cough and sputum, than non-smokers. Significantly lower mean F.E.V._1·0 values were found in smokers than in non-smokers aged 50 years and over. There was an association between the educational level attained and both the prevalence of symptoms and the F.E.V._1·0. Those with lower educational grades had a significantly higher prevalence of symptoms, especially cough and sputum. Those who had completed one year or more in college recorded higher F.E.V._s. These differences are the subject of further study. Differences in the prevalence of persistent cough, sputum or breathlessness between communities studied in the United States and the United Kingdom are small or absent. Bronchitic chest illnesses during the three years before interview, particularly those which recurred, appear however to be more common in Britain, and this may explain at least partly the greater disability and mortality from chronic respiratory disease in the United Kingdom than in the United States.