Abstract
RATIONALE: Disability guidelines are often based on pulmonary function testing, but factors other than lung function influence how an individual experiences physiologic impairment. Age may impact the perception of impairment in adults with chronic lung disease. OBJECTIVES: To determine if self-report of physical functional impairment differs between older adults with chronic lung disease compared with younger adults with similar degrees of lung function impairment. METHODS: The Lung Tissue Research Consortium provided data on 981 participants with chronic obstructive pulmonary disease and interstitial lung disease who were well characterized with clinical, radiological, and pathological diagnoses. We used multiple logistic regression to determine if responses to health status questions (from the Short Form-12 and St. George's Respiratory Questionnaire) related to perception of impairment differed in older adults (age ≥ 65 yr, n = 427) compared with younger adults (age < 65 yr, n = 393). MEASUREMENTS AND MAIN RESULTS: Pulmonary function was higher in older adults (median FEV1 %, 70) compared with younger adults (median FEV1 %, 62) (P < 0.001), whereas the median 6-minute-walk distance was similar between groups (372 m vs. 388 m, P = 0.21). After adjusting for potential confounders, older adults were less likely to report that their health limited them significantly in performing moderate activities (odds ratio [OR], 0.36; 95% confidence interval [CI], 0.22-0.58) or climbing several flights of stairs (OR, 0.51; 95% CI, 0.34-0.77). The odds of reporting that their physical health limited the kinds of activities they performed were reduced by 63% in older adults (OR, 0.37; 95% CI, 0.24-0.58), and, similarly, the odds of reporting that their health caused them to accomplish less than they would like were also lower in older adults (OR, 0.39; 95% CI, 0.25-0.60). The OR for reporting that their breathing problem stops them from doing most things or everything was 0.35 (95% CI, 0.22-0.55) in older adults versus younger adults. CONCLUSIONS: Older adults with chronic lung disease were less likely to report significant impairment in their activities compared with younger adults, suggesting they may perceive less limitation.