Baseline characteristics by BMI group.
| Characteristic | Nonobese (N = 74) | Obese I (N = 27) | Obese II (N = 19) | Obese III (N = 8) | P Valuea,b |
| Age, y, mean ± SD | 50.36 ± 10.59 | 48.06 ± 8.03 | 52.32 ± 10.78 | 48.05 ± 10.35 | 0.502 |
| Sex, % ( n ) | 0.014 | ||||
| Female | 54.1% (40) | 18.5% (5) | 36.8% (7) | 37.5% (3) | |
| Male | 46.0% (34) | 81.5% (22) | 63.2% (12) | 62.5% (5) | |
| Smoking status, % (n) | 0.294 | ||||
| Nonsmoker | 82.4% (61) | 92.6% (25) | 94.7% (18) | 75.0% (6) | |
| Smoker | 17.6% (13) | 7.4% (2) | 5.3% (1) | 25.0% (2) | |
| Insurance status, % (n) | 0.062 | ||||
| Non-WC | 81.1% (60) | 55.6% (15) | 66.7% (12) | 62.5% (5) | |
| WC | 18.9% (14) | 44.4% (12) | 33.3% (6) | 37.5% (3) | |
| Diabetic status, % ( n ) | 0.042 | ||||
| Nondiabetic | 89.2% (66) | 81.5% (66) | 89.5% (17) | 50.0% (4) | |
| Diabetic | 10.8% (8) | 8.5% (5) | 10.5% (2) | 50.0% (4) | |
| Ageless CCI, mean ± SD | 0.66 ± 0.92 | 0.59 ± 0.50 | 0.78 ± 1.06 | 1.88 ± 1.73 | 0.007 |
| Spinal diagnoses, % (n) | |||||
| Herniated nucleus pulposus | 83.8% (62) | 88.9% (24) | 89.5% (17) | 87.5% (7) | 0.923 |
| Degenerative disc disease | 5.4% (4) | 3.7% (1) | 5.3% (1) | 0.0% (0) | 0.907 |
| Foraminal stenosis | 12.2% (9) | 3.7% (1) | 15.8% (3) | 12.5% (1) | 0.496 |
aP value was calculated for each category using multivariate linear regression (continuous) or either χ2 analysis or Fisher’s exact test (categorical).
bBoldface indicates statistical significance.
CCI, Charlson Comorbidity Index; SD, standard deviation; WC, workers’ compensation.