Table 3: Comparison between young age and old age.

VariablesTotalAgeP values
<65-year old≧65-year old

Number of patients723735
Age (years)61.4 ± 11.353.0 ± 9.070.3 ± 4.8<0.001*
Gender
Male3723 (62.2%)14 (40.0%)0.060
Female3514 (37.8%)21 (60.0%)
Number of instrumented levels
One3117 (45.9%)14 (40.0%)0.611
Two4120 (54.1%)21 (60.0%)
Mean pre-op scores
VAS back pain6.3 ± 3.36.1 ± 3.46.4 ± 3.10.811
VAS leg pain7.0 ± 2.76.7 ± 3.07.4 ± 2.30.497
ODI (%)51.1 ± 19.650.4 ± 21.351.7 ± 17.80.612
Mean 24-month post-op scores
VAS back pain2.8 ± 2.92.9 ± 2.92.7 ± 2.90.754
VAS leg pain2.6 ± 3.22.7 ± 3.12.4 ± 3.20.474
ODI (%)23.4 ± 21.421.8 ± 22.025.2 ± 20.80.291
Serum glucose status
Type 2 DM153 (8.1%)12 (34.3%)0.006*
Euglycemia5734 (91.9%)23 (65.7%)
Blood pressure
Hypertensive94 (10.8%)5 (14.3%)0.656
Normotensive6333 (89.2%)30 (85.7%)

Mean values are presented ± SD.
* P < 0.05, statistically significant.
DM: diabetes mellitus.
VAS: visual analogue scale.
ODI: Oswestry disability index.