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Risk factors and comorbidities in the preclinical stages of chronic obstructive pulmonary disease.

RATIONALE
There is little information about comorbidities and their risk factors in the preclinical stages of chronic obstructive pulmonary disease (COPD).


OBJECTIVES
This study aims to investigate the prevalence of premorbid risk factors and comorbid diseases and its association with daily physical activity in subjects detected with COPD by spirometry screening.


METHODS
Sixty subjects with preclinical COPD (63 ± 6 yr; 68% [n = 41] male) were compared with 60 smoking control subjects (62 ± 7 yr; 70% [n = 42] male) and 60 never-smoking control subjects (62 ± 6 yr; 57% [n = 34] male). Comorbidities (cardiovascular, metabolic, and musculoskeletal disease) and daily physical activity (by multisensor activity monitor) were measured objectively.


MEASUREMENTS AND MAIN RESULTS
The prevalence of premorbid risk factors and comorbid diseases was significantly higher in preclinical COPD compared with age-matched never-smoking control subjects, but was similar to smoking control subjects not suffering from COPD. In preclinical COPD and smoking control subjects, the combination of cardiovascular disease and musculoskeletal disease was the most prevalent (15% [n = 9] and 12% [n = 7], respectively). In a multivariate logistic regression analysis, physical inactivity and smoking were found to be independent risk factors for having greater than or equal to two comorbidities.


CONCLUSIONS
Premorbid risk factors and comorbid diseases were more prevalent in the preclinical stages of COPD and smokers without COPD. Physical inactivity and smoking were more strongly associated with the presence of comorbidities compared with airflow obstruction. Clinical trial registered with www.clinicaltrials.gov (NCT 01314807).