Table 4.
Univariate and Case-Mix–Adjusted Regression Analysis of Physical Function Score
| Univariate Results |
Case-Mix–Adjusted Results |
||||
|---|---|---|---|---|---|
| Variables | No. | Estimate (95% CI) | P | Estimate (95% CI) | P |
| Age (/decade) | 375 | ||||
| ≤50 y | −8.90 (−12.5 to −5.24) | <0.001 | −9.13 (−12.7 to −5.49) | <0.001 | |
| >50 y | −0.34 (−3.86 to 3.18) | 0.9 | −0.09 (−3.59 to 3.41) | 0.9 | |
| Male | 375 | 8.37 (2.98 to 13.7) | 0.002 | 8.66 (3.44 to 13.8) | 0.001 |
| Black race | 375 | −1.83 (−7.28 to 3.62) | 0.5 | −0.44 (−5.68 to 4.80) | 0.9 |
| ESRD vintage (y) | 375 | 0.32 (−0.12 to 0.76) | 0.1 | 0.25 (−0.18 to 0.67) | 0.3 |
| Primary language not English | 375 | 6.69 (−0.36 to 13.7) | 0.06 | 4.77 (−2.36 to 11.9) | 0.2 |
| Education levela | 372 | ||||
| <High school graduate | 1.61 (−5.45 to 8.68) | 0.7 | −0.67 (−7.52 to 6.17) | 0.8 | |
| High school graduate | 2.50 (−4.04 to 9.05) | 0.5 | 1.81 (−4.45 to 8.08) | 0.5 | |
| Does not live with family vs lives with family | 372 | 4.23 (−1.80 to 10.2) | 0.2 | 4.37 (−1.49 to 10.2) | 0.1 |
| Insurance statusb | 372 | ||||
| Employer group health insurance or privately purchased |
−0.75 (−7.51 to 6.02) | 0.8 | 0.71 (−5.78 to 7.20) | 0.8 | |
| Government insurance for the poorc | 1.56 (−4.48 to 7.95) | 0.6 | −0.11 (−6.37 to 6.16) | 0.9 | |
| Diabetes | 370 | −19.2 (−24.2 to −14.1) | <0.001 | −16.3 (−21.5 to −11.0) | <0.001 |
| Congestive heart failure | 370 | −9.81 (−16.6 to −3.01) | 0.005 | −5.45 (−12.2 to 1.31) | 0.1 |
| Peripheral arterial disease | 370 | −24.2 (−32.0 to −16.4) | <0.001 | −22.9 (−30.6 to −15.3) | <0.001 |
| Stroke | 370 | −18.5 (−28.8 to −8.20) | <0.001 | −13.7 (−23.7 to −3.70) | 0.008 |
| enPCR (0.1 g/kg/d) | 371 | 1.17 (0.20 to 2.14) | 0.02 | 1.35 (0.40 to 2.31) | 0.005 |
| Residual renal clearance (mL/min) | 372 | 4.39 (−1.89 to 310.0) | 0.2 | 0.76 (−0.78 to 2.29) | 0.3 |
| Creatinine (mg/dL) | 372 | 2.26 (1.39 to 3.14) | <0.001 | 1.80 (0.84 to 2.75) | <0.001 |
| Phosphate (mg/dL) | 372 | 1.46 (−0.11 to 3.04) | 0.07 | 0.73 (−0.85 to 2.31) | 0.4 |
| Hemoglobin (g/dL) | 346 | 2.69 (0.54 to 4.84) | 0.01 | 2.42 (0.35 to 4.48) | 0.02 |
| PTH (0.1 pg/L) | 364 | 1.93 (−0.96 to 192.0) | 0.6 | 0.19 (−0.47 to 0.86) | 0.6 |
| Albumin (g/dL) | 372 | 1.16 (0.55 to 1.76) | <0.001 | 0.96 (0.37 to 1.55) | 0.002 |
| Calcium (mg/dL) | 364 | 1.06 (−2.00 to 4.11) | 0.5 | 2.25 (−0.71 to 5.20) | 0.1 |
| Bicarbonate (mmol/L) | 363 | −0.79 (−1.49 to −0.09) | 0.03 | −0.59 (−1.27 to 0.09) | 0.09 |
| LV mass (10 g) | 349 | −0.05 (−0.57 to 0.47) | 0.8 | −0.46 (−1.02 to 0.09) | 0.1 |
| BMI (kg/m2) | 353 | −0.56 (−0.91 to −0.21) | 0.002 | −0.47 (−0.81 to −0.13) | 0.007 |
| ICW volume/weight (dL/kg) | 351 | 11.7 (7.60 to 15.8) | <0.001 | 15.0 (8.18 to 21.9) | <0.001 |
| Phase angle (0.1°) | 351 | 0.40 (0.20 to 0.60) | <0.001 | 0.23 (0.04 to 0.43) | 0.02 |
| Randomly assigned vs not randomly assigned | 375 | 9.46 (1.60 to 17.3) | 0.02 | 9.66 (2.15 to 17.1) | 0.01 |
| Nocturnal vs daily trial | 375 | 2.41 (−3.67 to 8.50) | 0.4 | 2.76 (−3.11 to 8.63) | 0.4 |
Note: Physical Functioning is composed of 10 questions about mobility (moving a table, pushing a vacuum, lifting or carrying groceries, climbing several flights of stairs, climbing 1 flight of stairs, bending or stooping, walking 1 mile, walking several blocks, and walking 1 block) and self-care (bathing or dressing oneself).
Abbreviations: BMI, body mass index; CI, confidence interval; enPCR, equilibrated normalized protein catabolic rate; ESRD, end-stage renal disease; ICW, intracellular water; LV, left ventricular; PTH, parathyroid hormone.
The reference group is individuals with education beyond high school.
The reference group is government insurance not awarded by income level (Medicare plus Canadian Health).
Medicaid and/or other state/county programs.