Table 1 Baseline characteristics of the study cohorts
From: The burden of hip and knee osteoarthritis in Finnish occupational healthcare
All OA patients | OCH subcohort | Controls | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Hip | Knee | Hip/Knee | Hip | Knee | Hip/Knee | |||||||||
n/mean | %/SD | n/mean | %/SD | n/mean | %/SD | n/mean | %/SD | n/mean | %/SD | n/mean | %/SD | n/mean | %/SD | |
Sample size | 9040 | 17.7% | 42,028 | 82.3% | 51,608 | 100% | 6416 | 18.3% | 28,693 | 81.7% | 35,109 | 100% | 35,101 | 100% |
Mean follow-up (years) | n/a | n/a | n/a | n/a | n/a | n/a | 3.4 | 2.3 | 3.5 | 2.4 | 3.4 | 2.4 | 3.5 | 2.4 |
Gender (female) | 4902 | 54.2% | 23,849 | 56.7% | 28,751 | 56.3% | 3407 | 53.1% | 15,633 | 54.4% | 19,040 | 54.2% | 19,034 | 54.2% |
Mean age at index | 56.8 | 10.4 | 56.6 | 10.1 | 56.6 | 10.1 | 53.3 | 7.9 | 53.2 | 7.6 | 53.3 | 7.7 | 52.4 | 7.6 |
Age group at index | ||||||||||||||
18–29 | 98 | 1.1% | 328 | 0.8% | 426 | 0.8% | 78 | 1.2% | 271 | 0.9% | 349 | 1.0% | 406 | 1.2% |
30–39 | 410 | 4.5% | 1845 | 4.4% | 2255 | 4.4% | 369 | 5.8% | 1620 | 5.6% | 1989 | 5.7% | 2170 | 6.2% |
40–49 | 1687 | 18.7% | 8139 | 19.4% | 9826 | 19.2% | 1528 | 23.8% | 6990 | 24.4% | 8518 | 24.3% | 9703 | 27.6% |
50–59 | 3902 | 43.2% | 18,795 | 44.7% | 22,697 | 44.4% | 3347 | 52.2% | 15,356 | 53.5% | 18,703 | 53.3% | 18,634 | 53.1% |
60–64 | 1479 | 16.4% | 6487 | 15.4% | 7966 | 15.6% | 981 | 15.3% | 3961 | 13.8% | 4942 | 14.1% | 3664 | 10.4% |
≥65 | 1464 | 16.2% | 6434 | 15.3% | 7898 | 15.5% | 113 | 1.8% | 495 | 1.7% | 608 | 1.7% | 524 | 1.5% |
BMI available | 4012 | 44.4% | 18,014 | 42.9% | 22,026 | 43.1% | 3799 | 59.2% | 17,134 | 59.7% | 20,933 | 59.6% | 16,400 | 46.7% |
Mean BMI (kg/m2) | 28.7 | 5.3 | 30.4 | 5.9 | 30.1 | 5.9 | 28.6 | 5.2 | 30.4 | 5.9 | 30.1 | 5.8 | 27.6 | 4.9 |
BMI group | ||||||||||||||
< 25 | 1001 | 25.0% | 2959 | 16.4% | 3960 | 18.0% | 943 | 24.8% | 2780 | 16.2% | 3723 | 17.8% | 5422 | 33.1% |
25–30 | 1678 | 41.8% | 6811 | 37.8% | 8489 | 38.5% | 1607 | 42.3% | 6506 | 38.0% | 8113 | 38.8% | 6809 | 41.5% |
30–35 | 881 | 22.0% | 4778 | 26.5% | 5659 | 25.7% | 833 | 21.9% | 4552 | 26.6% | 5385 | 25.7% | 2918 | 17.8% |
35–40 | 306 | 7.6% | 2211 | 12.3% | 2517 | 11.4% | 284 | 7.5% | 2093 | 12.2% | 2377 | 11.4% | 905 | 5.5% |
> 40 | 146 | 3.6% | 1255 | 7.0% | 1401 | 6.4% | 132 | 3.5% | 1203 | 7.0% | 1335 | 6.4% | 346 | 2.1% |
Smoking status available | 2126 | 23.5% | 9816 | 23.4% | 11,942 | 23.4% | 2102 | 32.8% | 9656 | 33.7% | 11,758 | 33.5% | 9686 | 27.6% |
Non-smoker | 1572 | 73.9% | 7149 | 72.8% | 8721 | 73.0% | 1556 | 74.0% | 7028 | 72.8% | 8584 | 73.0% | 6600 | 68.1% |