Table 2.
Onset of knee pain at three years among people aged 50 and over with no knee pain at baseline by body mass index (BMI) category.
| BMI category at baseline | Knee Pain at 3 years | Unadjusted analysis | Adjusted analysisa | |||||
| n | n (%) | Relative Risk (RR) (95% Confidence Interval (CI)) | RRb (95% CI) | Potential cases avoidedc (% of all incident cases) | RR (95% CI) | RRb (95% CI) | Potential cases avoidedc (% of all incident cases) | |
| Normald | 960 | 216 (22.5) | 1.00 | - | - | 1.00 | - | - |
| Overweight | 809 | 196 (24.2) | 1.08 (0.91, 1.28) | 1.00 | 14 (2.9) | 1.08 (0.89, 1.32) | 1.00 | 15 (3.1) |
| Obese | 227 | 71 (31.3) | 1.39 (1.11, 1.74) | 1.29 (1.03, 1.62) | 16 (3.3) | 1.26 (0.95, 1.67) | 1.17 (0.88, 1.56) | 10 (2.1) |
| Total | 1996 | 483 (24.2) | 30 (6.2) | 25 (5.2) | ||||
a adjusted for age, gender, deprivation, anxiety, depression, previous knee injury, widespread pain measured at baseline
b obesity category compared to overweight
c number of cases which could have been avoided by reducing overweight people to normal and obese people to overweight
d Normal weight category includes individuals who were underweight.