Table 2.
Relationship between knee osteoarthritis, chronic obstructive pulmonary disease, and long-term physical activity in U.S. adults.
| Variable | Model 1 a | Model 2 b | ||||
|---|---|---|---|---|---|---|
| β | 95% CI | p | β | 95% CI | p | |
| Intercept | 211.4 | 203.1, 219.7 | <0.001 | 214.6 | 204.8, 224.4 | <0.001 |
| Time | −0.11 | −1.45, 0.67 | 0.708 | −0.10 | −0.52, 0.60 | 0.895 |
| Knee OA versus control | −9.44 | −17.7, −1.09 | 0.027 | −6.62 | −15.4, −2.19 | 0.014 |
| COPD versus knee OA | −16.9 | −26.7, −7.17 | 0.007 | −11.2 | −21.7, −0.67 | 0.037 |
Abbreviations: OA, osteoarthritis; CI, confidence interval; COPD, chronic obstructive pulmonary disease. a Model 1 adjusted for time, cohorts, age, sex, race, education, marital status, employment, and annual income. b Model 2 adjusted for Model 1 plus smoking, BMI, and comorbidities.