Table 2. Multivariable-adjusted odds ratios for incidence of persistent low back pain by potential confounders.
| Characteristic | Participants | Odds Ratioa | 95% CI |
|---|---|---|---|
| Age (yrs) | 1,152 | 0.98 | 0.93–1.03 |
| VO2max (ml/kg/min) | |||
| 1st quartile ≤36 | 301 | 1.00 (reference) | |
| 2nd quartile 37–42 | 285 | 1.22 | 0.68–2.20 |
| 3rd quartile 43–49 | 309 | 0.90 | 0.48–1.67 |
| 4th quartile ≥50 | 257 | 0.81 | 0.41–1.58 |
| Alcohol intake | |||
| None | 413 | 1.00 (reference) | |
| 1–20 g/day | 517 | 0.73 | 0.44–1.22 |
| ≥21 g/day | 222 | 1.19 | 0.66–2.15 |
| Current smokers | |||
| None | 422 | 1.00 (reference) | |
| 1–20 cigarettes/day | 457 | 1.20 | 0.74–1.94 |
| ≥21 cigarettes/day | 273 | 0.68 | 0.36–1.28 |
aAdjusted for all items in the table.
CI: confidence interval; VO2max: maximal oxygen uptake