Table 1.
General characteristics of the study participants
| Baseline variables | Total cohort, n = 3011 | Study subjects, n = 1335 | |||
|---|---|---|---|---|---|
| All subjects at baseline | OA at baseline, n = 238 | OA at follow-up, n = 326 | No OA at follow-up, n = 955 | ||
| Female, n (%) | 1694 (56) | 743 (55.7) | 144 (60.5) | 195 (59.8) | 519 (54.4) |
| Age* | 65.2 (8.43) | 63.1 (6.48) | 66.4 (7.90) | 66.02 (7.72) | 62.13 (5.71) |
| Body mass index, kg/m2* | 27.3 (4.23) | 27.04 (3.85) | 27.96 (4.11) | 28.01 (4.29) | 26.69 (3.65) |
| Current alcohol drinker, n (%) | 2455 (81.5) | 1146 (85.8) | 205 (86.1) | 277 (85) | 822 (86.2) |
| Current smoking, n (%) | 692 (23) | 298 (22.3) | 37 (15.5) | 59 (18.1) | 226 (23.7) |
| Low level of education, n (%) | 424 (31.8) | 999 (33.9) | 74 (31.1) | 103 (31.6) | 298 (31.2) |
| Diabetes, n (%) | 182 (6.0) | 68 (5.1) | 12 (5.0) | 21 (6.4) | 42 (4.4) |
| Knee pain, n (%) | 725 (24.1) | 328 (24.6) | 96 (40.3) | 128 (39.3) | 185 (19.4) |
| Hip pain, n (%) | 458 (15.2) | 207 (15.5) | 48 (20.2) | 62 (19) | 132 (13.8) |
| Knee OA, n (%) | 339 (11.3) | 185 (13.9) | 185 (78.1) | 185 (56.7) | - |
| Hip OA, n (%) | 141 (4.7) | 68 (5.1) | 68 (28.7) | 68 (20.9) | - |
| uCTX-II*, ng/mmol | - | 2.3 (0.23) | 2.42 (0.27) | 2.40 (0.26) | 2.27 (0.22) |
| COMP*, U/L | - | 1.03 (0.10) | 1.06 (0.10) | 1.06 (0.10) | 1.02 (0.10) |
| CRP*, mg/l | - | 0.02 (0.49) | 0.07 (0.48) | 0.12 (0.49) | -0.02 (0.48) |
| CRPM*, ng/ml | - | 1.01 (0.18) | 1.01 (0.18) | 1.02 (0.18) | 1.01 (0.17) |
| C1M*, ng/ml | - | 1.59 (0.17) | 1.60 (0.18) | 1.61 (0.18) | 1.58 (0.17) |
OA osteoarthritis, uCTX-II (urinary) type II collagen degradation, COMP cartilage oligomeric protein, CPR C-reactive protein, CRPM matrix metalloproteinase-dependent degradation of CRP, C1M connective tissue type I collagen turnover
*Mean (SD); levels of biomarkers are log10-trasformed