Table 1.
Characteristics of the study populationa
| Characteristic | Knee rOA (n = 1635)b | Knee sxOA (n = 1605)b |
|---|---|---|
| Mean whole blood Pbc, μg/dl (±SD) | 2.4 (2.5) | 2.4 (2.5) |
| Mean age, yr (±SD) | 65.3 (11.0) | 65.2 (11.0) |
| Mean BMI, kg/m2 (±SD) | 31.2 (7.1) | 31.2 (7.1) |
| African-Americans, n (%) | 582 (35.6%) | 573 (35.7%) |
| Women, n (%) | 1085 (66.4%) | 1069 (66.6%) |
| Current smoker, n (%) | 259 (16.5%) | 257 (16.6%) |
| Current drinker, n (%) | 333 (21.2%) | 329 (21.2%) |
| Knee outcomes | rOA | sxOA |
| Present, n (%) | 659 (40.3%) | 384 (23.9%) |
| Bilateral, n (%) | 377 (23.1%) | 170 (10.6%) |
| Moderate to severe, n (%) | 426 (26.1%) | 271 (16.9%) |
arOA, radiographic osteoarthritis; sxOA, symptomatic osteoarthritis; SD, standard deviation; Pb, lead; BMI, body mass index; bsamples with complete data for knee rOA and knee sxOA, respectively; cmedian, 1.8 μg/dl (range, 0.3 to 42.0 μg/dl).