Table 2.
Hazard ratios for subsequent strokes after lumbar spinal fusion surgery (n = 18,135, 2005–2008)
| Stroke during 3-year follow-up | Comparison group | Lumbar spinal fusion group | (95 % CI) | P value |
|---|---|---|---|---|
| Any stroke | ||||
| Crude hazard ratio | 1.00 | 1.02 | (0.78–1.33) | 0.896 |
| Adjusted hazard ratioa | 1.00 | 0.83 | (0.59–1.17) | 0.293 |
| Hemorrhagic stroke | ||||
| Crude hazard ratio | 1.00 | 0.62 | (0.27–1.42) | 0.254 |
| Adjusted hazard ratioa | 1.00 | 0.74 | (0.27–2.04) | 0.739 |
| Ischemic stroke | ||||
| Crude hazard ratio | 1.00 | 1.07 | (0.81–1.42) | 0.619 |
| Adjusted hazard ratioa | 1.00 | 0.81 | (0.56–1.16) | 0.250 |
aAdjustment was made for demographic characteristics (e.g., age, sex, insurance level, geographic location, and urbanization level), comorbidities (i.e., hypertension, diabetes, valvular heart disease, arrhythmia, cardiovascular disease, and Charlson’s comorbidity index), medications (i.e., aspirin, nitrates, lipid-lowering drugs, anticoagulants, and NSAIDs), and baseline propensity scores