4.1 Patient characteristics
The average age of the patients was 62.72 ± 12.10 years old, and 40.6% (n = 43) of them were men. 67.9% (n=72) had a medical history of hypertension, 20.8% (n=22) were diabetes, and 34.0% (n=36) were CHD. The mean ± SD of the diameter of the radial artery was 2.22 ± 0.41mm. The mean ± SD of the diameter of the distal radial artery was 2.0586 ± 0.33mm. There was a significant difference in the diameter of the radial artery and the distal radial artery (P = 0.002). The mean difference in size between radial artery and distal radial artery was 0.16 mm. The distal radial artery showed a mean diameter reduction of about 7.2%. The diameter of the distal radial artery in males and females was 0.217 ± 0.031, 0.198 ± 0.033, respectly (P = 0.003). According to the mean of the diameter of the distal radial artery, the patients were divided into two groups——diameter ≥ 2.0586 mm group (n = 53) and diameter < 2.0586 mm group (n = 53). Patients’ characteristics are presented in Table 1.
4.2 Univariate and multivariate logistic regression analysis
The male was 25.5% (n=27) in the diameter ≥ 2.0586 mm group and 15.1% (n=16) in the diameter < 2.0586 mm group (OR = 2.401, P = 0.031). The percentage of weight ≥ 63 kg in the diameter ≥ 2.0586 mm group was larger than the diameter < 2.0586 mm group (OR = 2.325, P = 0.034). By comparing the two groups, the related factors and independent predictors of the distal radial artery diameter ≥ 2.0586 mm were obtained. Male gender, height ≥ 160 cm, weight ≥ 63 kg, body mass index (BMI) ≥ 24 kg/m2, and body surface area (BSA) ≥ 1.6573 m2 were related factors. Male gender and BMI ≥ 24 kg/m2 were independent predictors. Both BMI and BSA were calculated according to height and weight, so we did not carry out multivariate logistics regression for them at the same time. We put them into multivariate logistics regression respectively. Therefore there were three models (Table 2).