Table 3.
Cumulative odds ratios (COR) and their 95% confidence intervals (CI) from multiple ordinal logistic regressions of the lumbar disk degeneration sum score (in four-class ordinal scale) on body mass index (BMI), physical activity per week and pack-years of smoking
|
Explanatory factors |
Males |
Females |
|---|---|---|
| N = 230 | N = 317 | |
| |
COR (95% CI) |
COR (95% CI) |
| BMI at 16 years (kg/m2; quartiles) |
|
|
| I |
1.00 |
1.00 |
| II |
1.44 (0.73–2.84) |
0.67 (0.37–1.23) |
| III |
1.64 (0.83–3.25) |
0.99 (0.54–1.81) |
| IV |
2.35 (1.19–4.65) |
1.29 (0.72–2.32) |
| Physical activity level# (MET hours/week; quartiles) |
|
|
| I |
1.00 (0.51–1.97) |
1.38 (0.76–2.50) |
| II |
1.00 |
1.00 |
| III |
1.27 (0.65–2.49) |
1.27 (0.69–2.34) |
| IV |
1.27 (0.65–2.50) |
1.52 (0.84–2.75) |
| Smoking (pack-years*) |
|
|
| None |
1.00 |
1.00 |
| 0.01-3.99 |
1.47 (0.76–2.83) |
1.09 (0.65–1.83) |
| ≥4.00 | 2.41 (0.99–5.86) | 1.59 (0.67–3.76) |
# Metabolic equivalent (MET) hours per week calculated from physical activity outside school hours; mean value at 16 and 19 years.
* Years of smoking multiplied by the packs of cigarettes smoked daily.