Excessive lung function declines and risk of death: implications for medical monitoring.
Sircar-KD; Hnizdo-E; Petsonk-EL
Proc Am Thorac Soc 2006 Apr; 3(Abstracts):A494
Rate of decline in lung function has been found to predict all-cause mortality, but detailed quantitative relationships have not yet been derived for this outcome. This study investigates the predictive effect of certain numeric indices of excessive lung function decline and implications for subsequent mortality. Spirometry results were available for 2,467 US white male coal miners who had performed two spirometry tests at least 7 years apart (mean 13.4 yrs) and whose vital status was followed up to 20 years (mean 12.1 yrs) from the last test. A nonparametric locally weighted regression (LOESS) method was used to describe the relationship between rate of decline and mortality. Rates of decline were then categorized based on commonly used cutoff points (30, 60, and 90 mL/yr). A Cox proportional hazard model was used to estimate the adjusted relative risk of all-cause mortality (RR) by decline. Covariates included age, change in body mass index (BMI), smoking (pack-years), and height-adjusted initial FEV1. The adjusted RR was also calculated for never smokers and for those whose initial FEV1 was above the lower limit of normal (FEV1>LLN). FEV1 declines exceeding 60 mL/yr were associated with increasing risk of all-cause mortality in the overall cohort, and declines exceeding 90 mL/yr were associated with increased mortality in two subgroupsthose who had an initial normal FEV1 and, importantly, those who had never smoked.
Lung-function; Risk-factors; Risk-analysis; Mortality-rates; Mortality-data; Spirometry; Coal-miners; Coal-mining; Underground-miners; Underground-mining; Miners; Mining-industry; Surveillance
Abstract; Conference/Symposia Proceedings
Issue of Publication
Disease and Injury: Asthma and Chronic Obstructive Pulmonary Disease; Construction
Proceedings of the American Thoracic Society