Combined effect of lung function level and decline increases morbidity and mortality risks
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Lung function level and decline are each predictive of morbidity and mortality. Evaluation of the combined effect of these measurements may help further identify high-risk groups. Using Copenhagen City Heart Study longitudinal spirometry data (n = 10,457), 16–21 year risks of chronic obstructive pulmonary disease (COPD) morbidity, COPD or coronary heart disease mortality, and all-cause mortality were estimated from combined effects of level and decline in forced expiratory volume in one second (FEV1). Risks were evaluated using Cox proportional hazards models for individuals grouped by combinations of baseline predicted FEV1 and quartiles of slope. Hazard ratios (HR) and 95 % confidence intervals (CI) were estimated using stratified analysis by gender, smoking status, and baseline age (≤45 and >45). For COPD morbidity, quartiles of increasing FEV1 decline increased HRs (95 % CI) for individuals with FEV1 at or above the lower limit of normal (LLN) but below 100 % predicted, reaching 5.11 (2.58–10.13) for males, 11.63 (4.75–28.46) for females, and 3.09 (0.88–10.86) for never smokers in the quartile of steepest decline. Significant increasing trends were also observed for mortality and in individuals with a baseline age ≤45. Groups with ‘normal’ lung function (FEV1 at or above the LLN) but excessive declines (fourth quartile of FEV1 slope) had significantly increased mortality risks, including never smokers and individuals with a baseline age ≤45.
KeywordsChronic obstructive pulmonary disease Morbidity Mortality Respiratory symptoms Spirometry
The National Institute for Occupational Safety and Health funded this research. The authors thank Dr. Michael Andrew, of the National Institute for Occupational Safety and Health, for his helpful comments.
Conflict of interest
The authors declare that they have no conflict of interest.
- 3.Krzyzanowski M, Jedrychowski W, Wysocki M. Factors associated with the change in ventilatory function and the development of chronic obstructive pulmonary disease in a 13-year follow-up of the Cracow Study. Risk of chronic obstructive pulmonary disease. Am Rev Respir Dis. 1986;134:1011–9.PubMedGoogle Scholar
- 20.American Thoracic Society/European Respiratory Society Task Force. Standards for the diagnosis and management of patients with COPD, version 1.2. 2004. www.thoracic.org/go/copd. Accessed 17 Feb 2011.
- 30.Quanjer PH, Tammeling GJ, Cotes JE, Pedersen OF, Peslin R, Yernault JC. Lung volumes and forced ventilatory flows. Report working party standardization of lung function tests, European community for steel and coal. Official statement of the European Respiratory Society. Eur Respir J Suppl. 1993;16:5–40.PubMedGoogle Scholar