Table 4.
Crude rate and relative risk of KR due to primary OA in 161,700 Norwegian women
| No. of participants | Person-years | No. of knee replacements | KRs per 10,000 person-years (crude rate) | Multivariate adjusted RR* (95% CI) | |
|---|---|---|---|---|---|
|
Body Mass Index, kg/m
2
|
|
||||
| <21.6 |
40,526 |
489,541 |
35 |
0.7 |
1 |
| 21.7-23.5 |
39,562 |
477,775 |
73 |
1.5 |
1.93 (1.29-2.89) |
| 23.6-26.1 |
40,691 |
491,052 |
177 |
3.6 |
3.92 (2.72-5.64) |
| > = 26.2 |
40,911 |
491,705 |
608 |
12.4 |
11.06 (7.83-15.62) |
| P (test for trend) |
|
|
|
|
<0.0001 |
|
Physical activity at work
|
|
||||
| Sedentary |
46,050 |
555,499 |
201 |
3.6 |
1 |
| Moderate |
84,368 |
1,017,358 |
498 |
4.9 |
1.18 (1.00-1.40) |
| Intermediate |
27,744 |
334,751 |
149 |
4.5 |
1.30 (1.05-1.61) |
| Intensive |
3,343 |
40,230 |
45 |
11.2 |
2.29 (1.65-3.18) |
| P (test for trend) |
|
|
|
|
<0.0001 |
|
Physical activity at leisure
|
|
||||
| Sedentary |
31,322 |
377,346 |
190 |
5.0 |
1 |
| Moderate |
113,127 |
113,127 |
624 |
55.2 |
0.99 (0.84-1.16) |
| Intermediate |
16,204 |
16,204 |
75 |
46.3 |
0.92 (0.70-1.21) |
| Intensive |
968 |
11,687 |
4 |
3.4 |
1.72 (0.64-4.65) |
| P (test for trend) |
|
|
|
|
0.797 |
|
Height
|
|
||||
| < 161 |
44,123 |
531,632 |
325 |
6.1 |
1 |
| 162-165 |
42,320 |
510,399 |
238 |
4.7 |
1.10 (0.93-1.30) |
| 166-169 |
38,461 |
464,179 |
150 |
3.2 |
0.93 (0.77-1.14) |
| > = 170 |
36,791 |
443,925 |
180 |
4.1 |
1.48 (1.23-1.80) |
| P (test for trend) |
|
|
|
|
0.003 |
|
Smoking
|
|
||||
| Never smoker |
65,929 |
794,420 |
526 |
6.6 |
1 |
| Former smoker |
31,174 |
376,055 |
163 |
4.3 |
0.81 (0.68-0.96) |
| Smoker |
64,597 |
779,720 |
204 |
2.6 |
0.66 (0.56-0.78) |
| P (test for trend) | <0.0001 | ||||
*Adjusted for age at screening, height, smoking habits, BMI and physical activity at work, and at leisure time.