Rapid declines in FEV1 and subsequent respiratory symptoms, illnesses, and mortality in coal miners in the United States.

Coal mine dust exposure is associated with accelerated loss of lung function. We assessed long-term health outcomes in two groups of underground coal miners who during previous mine surveys had shown either high rates of FEV1 decline (cases, n = 310) or relatively stable lung function (referents, n = 324). Cases and referents were matched initially for age, height, smoking status, and FEV1. We determined vital status for 561 miners, and obtained a follow-up questionnaire for 121 cases and 143 referents. Responses on the follow-up questionnaire were compared with those on the last previous mine health survey questionnaire. Cases showed a greater incidence of symptoms than did referents for cough, phlegm production, Grades II and III dyspnea, and wheezing, and greater incidences than referents of chronic bronchitis and self- reported asthma and emphysema. More cases than referents (15% versus 4%) left mining before retirement because of chest illnesses. After controls were applied for age and smoking, cases had twice the risk of dying of cardiovascular and nonmalignant respiratory diseases and a 3.2-fold greater risk of dying of chronic obstructive pulmonary disease than did referents. Rapid declines in FEV1 experienced by some coal miners are associated with subsequent increases in respiratory symptoms, illnesses, and mortality from cardiovascular and nonmalignant respiratory diseases.