Table 2. The risk factors of intracranial and extracranial arterial stenosis.
| OR | 95% CI | P | |
|---|---|---|---|
| Isolated ICAS | |||
| Age | 1.063 | 1.028–1.098 | <0.001 |
| Male | 1.872 | 1.296–2.704 | 0.001 |
| Average brachial SBP | 1.002 | 1.001–1.003 | 0.005 |
| Inter-arm DBP difference | 1.012 | 1.004–1.021 | 0.004 |
| Diabetes | 1.511 | 1.001–2.300 | 0.049 |
| Anti-hypertensive treatment | 0.539 | 0.291–0.998 | 0.048 |
| Isolated ECAS | |||
| Age | 1.064 | 1.026–1.104 | 0.001 |
| Inter-arm SBP difference | 1.01 | 1.004–1.017 | 0.001 |
| Low-density lipoprotein | 1.417 | 1.078–1.862 | 0.012 |
| COMB | |||
| Age | 1.129 | 1.083–1.178 | <0.001 |
| Male | 2.757 | 1.780–4.270 | <0.001 |
| Average brachial SBP | 1.002 | 1.001–1.003 | 0.003 |
| Low-density lipoprotein | 1.756 | 1.316–2.343 | <0.001 |
| Diabetes | 1.712 | 1.042–2.812 | 0.034 |
| Statin use | 0.314 | 0.154–0.641 | 0.001 |
Stepwise logistic regression in forward conditional method was performed to test the risk factors of stenosis. The variables tested in the equation included age, sex, body mass index, current smoking and drinking status, diabetes, logw-density lipoprotein, average brachial SBP, heart rate, anti-hypertensive treatment, statin use, inter-arm SBP difference and inter-arm DBP difference. The odds ratio expressed the risk in the ICAS and ECAS group compared with the non-stenosis group. Isolated ECAS, extracranial arterial stenosis only; Isolated ICAS, intracranial arterial stenosis only; COMB, combined extra- and intracranial arterial stenosis; OR, odds ratio; SBP, systolic blood pressure; DBP, diastolic blood pressure.