Table 2.
Associations of weight-related measures with LBP and physician-diagnosed low back disorders
| LBP, preceding 30 days (n=1363) |
Chronic LBP syndrome (n=1350) |
Radiating LBP, preceding 30 days (n=1363) |
Sciatica, assessed by physician (n=1350) |
|||||
|---|---|---|---|---|---|---|---|---|
| PR/OR | 95% CI* | PR/OR | 95% CI* | PR/OR | 95% CI* | PR/OR | 95% CI* | |
| Longitudinal associations between BMI at baseline and outcomes at follow-up | ||||||||
| BMI at baseline† | 1.07 | 0.96 to 1.19 | 1.18 | 0.96 to 1.44 | 1.26 | 1.08 to 1.46 | 1.15 | 0.89 to 1.50 |
| Life course BMI (Z score)‡ | 0.99 | 0.86 to 1.14 | 1.09 | 0.87 to 1.36 | 1.23 | 1.03 to 1.48 | 1.10 | 0.83 to 1.46 |
| Cross-sectional associations between weight-related factors, and outcomes at follow-up | ||||||||
| BMI (continuous)§ | 0.95 | 0.84 to 1.07 | 1.09 | 0.90 to 1.33 | 1.16 | 0.99 to 1.35 | 1.10 | 0.86 to 1.41 |
| BMI (categorical), kg/m2 | ||||||||
| <25 | 1.00 | 1.00 | 1.00 | 1.00 | ||||
| 25–29.9 | 1.03 | 0.80 to 1.34 | 0.95 | 0.60 to 1.51 | 1.42 | 0.97 to 2.08 | 0.84 | 0.47 to 1.51 |
| ≥30 | 0.88 | 0.61 to 1.25 | 1.13 | 0.63 to 2.00 | 1.64 | 1.02 to 2.65 | 1.04 | 0.50 to 2.15 |
| Waist circumference (continuous)¶ | 1.00 | 0.88 to 1.12 | 1.13 | 0.92 to 1.38 | 1.15 | 0.98 to 1.35 | 1.18 | 0.92 to 1.52 |
| Waist circumference (categorical), cm | ||||||||
| <94 | 1.00 | 1.00 | 1.00 | 1.00 | ||||
| 94–101.9 | 1.11 | 0.83 to 1.47 | 1.04 | 0.63 to 1.73 | 1.03 | 0.69 to 1.53 | 0.91 | 0.47 to 1.75 |
| ≥102 | 1.03 | 0.77 to 1.39 | 1.24 | 0.75 to 2.03 | 1.31 | 0.88 to 1.96 | 1.19 | 0.64 to 2.23 |
| Waist-to-height ratio | ||||||||
| Normal (≤0.5) | 1.00 | 1.00 | 1.00 | 1.00 | ||||
| Critical (>0.5) | 0.96 | 0.76 to 1.22 | 1.33 | 0.75 to 1.72 | 1.44 | 1.02 to 2.04 | 0.88 | 0.52 to 1.49 |
Significant associations have been marked with bold.
*PRs (for the longitudinal analyses) and ORs (for cross-sectional analyses) and their 95% CIs are adjusted for age, smoking and education.
†Continuous variable, one SD increase, corresponding to 3.0 kg/m2 for baseline BMI.
‡One unit increment in Z score, corresponding to 2.92 units of BMI during follow-up.
§Continuous variable, one SD increase, corresponding to 4.0 kg/m2 for follow-up BMI.
¶Continuous variable, one SD increase, corresponding to 11 cm for waist circumference at follow-up.
BMI, body mass index; LBP, low back pain; PR, prevalence ratio.