Occurrence of radiographic knee osteoarthritis in relation to knee pain duration and persistence
| Adjusted OR (95% CI) | |||||
|---|---|---|---|---|---|
| Variable | Total | Patients with ROA,n (%) | OR (95% CI) | For age and sex | For age, sex and BMI |
| BMI, body mass index; ROA, radiographic osteoarthritis. | |||||
| When pain or aching or stiffness in the last month is dichotomised for most/all days with reference to no/few/some, the age-sex-adjusted OR (95% CI) is 1.6 (1.1 to 2.1). | |||||
| Total duration of symptoms (years) | |||||
| <1 | 91 | 46 (51) | 1 | 1 | 1 |
| 1–5 | 257 | 172 (67) | 2.0 (1.2 to 3.2) | 2.2 (1.3 to 3.7) | 2.0 (1.2 to 3.4) |
| 5–10 | 150 | 100 (67) | 2.0 (1.2 to 3.3) | 1.9 (1.1 to 3.4) | 1.9 (1.0 to 3.3) |
| ⩾10 | 247 | 191 (77) | 3.3 (2.0 to 5.5) | 3.2 (1.9 to 5.4) | 3.0 (1.7 to 5.2) |
| Last time pain free for a month | |||||
| <3 months | 232 | 153 (66) | 1 | 1 | 1 |
| 3–6 months | 94 | 60 (64) | 0.9 (0.6 to 1.5) | 0.9 (0.6 to 1.6) | 1.1 (0.6 to 1.8) |
| 7–12 months | 57 | 31 (54) | 0.6 (0.3 to 1.1) | 0.6 (0.3 to 1.1) | 0.5 (0.3 to 1.0) |
| 1–2 years | 68 | 46 (68) | 1.1 (0.6 to 1.9) | 1.3 (0.7 to 2.3) | 1.1 (0.6 to 2.1) |
| 3–5 years | 120 | 83 (69) | 1.2 (0.7 to 1.9) | 1.2 (0.7 to 2.0) | 1.1 (0.7 to 1.9) |
| 6–10 years | 83 | 60 (72) | 1.4 (0.8 to 2.3) | 1.2 (0.7 to 2.2) | 1.1 (0.6 to 2.0) |
| ⩾10 years | 91 | 76 (84) | 2.6 (1.4 to 4.9) | 2.5 (1.3 to 4.7) | 2.1 (1.1 to 4.1) |
| Knee pain in the past 12 months | |||||
| <7 days | 56 | 28 (50) | 1 | 1 | 1 |
| 1–4 weeks | 92 | 56 (61) | 1.6 (0.8 to 3.0) | 1.8 (0.9 to 3.6) | 1.8 (0.9 to 3.8) |
| 1–<3 months | 109 | 69 (63) | 1.7 (0.9, 3.3) | 1.8 (0.9, 3.6) | 1.9 (0.9 to 3.8) |
| ⩾3 months | 435 | 324 (74) | 2.9 (1.7 to 5.1) | 2.7 (1.5 to 5.0) | 2.7 (1.4 to 4.9) |
| Days of knee pain in the past 6 months | |||||
| 1–30 | 352 | 226 (64) | 1 | 1 | 1 |
| 31–89 | 192 | 125 (65) | 1.0 (0.7 to 1.5) | 1.0 (0.7 to 1.5) | 0.9 (0.6 to 1.3) |
| ⩾90 | 201 | 158 (79) | 2.1 (1.4 to 3.1) | 1.9 (1.2 to 2.8) | 1.6 (1.0 to 2.4) |
| Pain, aching or stiffness in the past month | |||||
| No days | 37 | 14 (38) | 1 | 1 | 1 |
| Few days | 176 | 120 (68) | 3.5 (1.7 to 7.4) | 4.0 (1.8 to 8.9) | 3.8 (1.7 to 8.4) |
| Some days | 192 | 123 (64) | 2.9 (1.4 to 6.1) | 3.2 (1.5 to 6.9) | 2.9 (1.3 to 6.3) |
| Most days | 218 | 153 (70) | 3.9 (1.9 to 8.0) | 4.1 (1.9 to 8.8) | 3.5 (1.6 to 7.6) |
| All days | 122 | 99 (81) | 7.1 (3.2 to 15.8) | 6.9 (3.0 to 16.1) | 5.6 (2.4 to 13.2) |