Table 2. Multivariate logistic regression analysis: risk factors for knee pain.
| Unadjusted OR | 95% CI | P value* | |
|---|---|---|---|
| Age | 1.03 | 1.01–1.04 | <0.001 |
| Female | 2.15 | 1.67–2.79 | <0.001 |
| Obesity† | 1.18 | 0.95–1.46 | 0.146 |
| RKOA | 2.20 | 1.78–2.74 | <0.001 |
| DLEM‡ | 1.54 | 1.09–2.17 | 0.015 |
| Stiffness | 16.15 | 12.04–21.66 | <0.001 |
| Osteoporosis | 1.07 | 0.83–1.38 | 0.607 |
| Current smoker | 1.00 | 0.71–1.39 | 0.985 |
| Low income (Ref: high income) § | 1.26 | 0.93–1.69 | 0.133 |
| Education (Ref: high education) || | Ref | ||
| Low | 1.72 | 1.09–2.71 | 0.021 |
| Moderate | 1.07 | 0.68–1.68 | 0.784 |
| Experience of bed rest within a month | 2.49 | 1.81–3.43 | <0.001 |
Predictors for increased knee pain were examined using multivariate logistic regression analysis.
* P < 0.05 was considered significant. DLEM = Decreased lower extremity muscle mass; OR = odds ratio; RKOA = Radiographic knee osteoarthritis.
† Obesity was defined as BMI > 25 kg/m2.
‡ DLEM was defined as an LMI was below 2 standard deviations from the mean in a sex-matched young reference group.
§ Income status was categorized in three groups (low, less than 670 USD dollars a month; moderate, less than 2,200 USD dollars a month; high, more than 2,200 USD dollars a month).
|| Education level was categorized in three groups (low, less than elementary school; moderate, middle and high school; high, more than university).