Respiratory impairment measure | Prospective disability measure* | |
Primary | Secondary | |
Increase in proportion of activities unable to perform (n=1051) | Development of ≥1 activity unable to perform in those with no baseline disability (n=777) | |
Forced expiratory volume in 1 s | ||
Base model† |
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Base model + covariates† |
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Baseline oxygen saturation | ||
Base model |
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Base model + covariates |
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↵* Incident disability was based on two measures. Primary disability outcome = an increase in the proportion of activities that subject is unable to perform from wave 1 to wave 2. A significant increase was defined as that exceeding 1 SE of measurement (see Methods). Secondary outcome was development of at least one new activity that subject is unable to perform among subcohort who had no disability at baseline.
↵† Results are from logistic regression analysis and are presented as ORs (95% CIs). ORs are expressed for a 1 l decrement of FEV1 and 5% decrement of oxygen saturation. Baseline model used the following predictor variables: respiratory impairment measure plus age, sex, race, and height. Covariates (potential confounders) = race, educational attainment, household income, and smoking status.