Table 3.
Univariate analysis for TR jet velocity and FMD
| Parameter | Parameter estimate | 95% CI | R2 | P value |
|---|---|---|---|---|
| Univariate TR jet velocity (cm/s) vs (X) | ||||
| Transfusion status (transfused) | −13.07 | −20.84 to −5.28 | 0.13 | .001 |
| FMD (%) | −5.94 | −8.74 to −3.14 | 0.2 | <.0001 |
| Sex (female) | −8.8 | −16.4 to −1.3 | 0.06 | .02 |
| Height (cm) | 0.74 | 0.07 to 1.40 | 0.06 | .03 |
| Hct (%) | −3.35 | −5.01 to −1.68 | 0.18 | .0001 |
| Hb (g/dL) | −8.67 | −13.67 to −3.67 | 0.14 | .0009 |
| HgS (%) | 0.52 | 0.22 to 0.82 | 0.16 | .001 |
| Reticulocyte count (×106/μL) | 2.27 | 0.78 to 3.77 | 0.12 | .003 |
| LDH (U/L) | 0.02 | 0.006 to 0.04 | 0.09 | .01 |
| Arg:Orn | −98.3 | −175.5 to −21.2 | 0.08 | .01 |
| ln(plasma free Hb) | 22.06 | 10.9 to 33.2 | 0.19 | .0002 |
| Viscosity at 300 s−1 | −24.73 | −42.44 to −7.03 | 0.13 | .007 |
| Univariate FMD (%) vs (X) | ||||
| Transfusion status (nontransfused) | −0.65 | −1.55 to 0.25 | 0.08 | .15 |
| Transfusion status (pretransfusion) | −0.43 | −1.33 to 0.47 | .34 | |
| Sex (female) | 0.94 | 0.34 to 1.56 | 0.12 | .003 |
| Height (cm) | −0.07 | −0.12 to −0.03 | 0.12 | .003 |
| Body surface area (m2) | −2.67 | −5.13 to −0.19 | 0.06 | .04 |
| Cardiac stroke volume (mL) | −0.02 | −0.05 to 0.001 | 0.06 | .04 |
| Hct (%) | 0.14 | 0.005 to 0.28 | 0.06 | .04 |
| Reticulocyte count (×106/μL) | −0.14 | −0.26 to −0.03 | 0.09 | .01 |
| HgS (%) | −0.03 | −0.05 to −0.0005 | 0.07 | .05 |
| LDH (U/L) | −0.001 | −0.002 to 0.0001 | 0.05 | .07 |
| ln(plasma free Hb) | −1.98 | −2.79 to −1.16 | 0.27 | <.0001 |
Using the method of least squares, univariate linear regression was performed using either TR jet velocity or flow-mediated dilation of the brachial artery as the dependent variable, with multiple hematologic, rheologic, and vital sign/demographic data as the independent predictors.