Table 2.
Univariate and Case-Mix–Adjusted Regression Analysis of Short Physical Performance Battery Score
| Univariate |
Case-Mix–Adjusted |
||||
|---|---|---|---|---|---|
| Variables | No. | OR (95% CI) | P | OR (95% CI) | P |
| Age (/decade) | 375 | 0.61 (0.53-0.71) | <0.001 | 0.60 (0.52-0.70) | <0.001 |
| Male | 375 | 2.03 (1.37-3.00) | <0.001 | 2.01 (1.34-3.01) | <0.001 |
| Black race | 375 | 0.58 (0.40-0.86) | 0.007 | 0.58 (0.39-0.87) | 0.009 |
| ESRD vintage (/1 y) | 375 | 1.01 (0.98-1.05) | 0.4 | 1.00 (0.97-1.03) | 0.9 |
| Primary language not English | 375 | 0.90 (0.55-1.49) | 0.7 | 0.53 (0.30-0.92) | 0.02 |
| Education levela | 372 | ||||
| <High school graduate | 3.80 (0.68-21.3) | 0.1 | 4.81 (0.78-29.7) | 0.09 | |
| High school graduate | 3.80 (0.68-21.0) | 0.1 | 5.98 (0.98-36.5) | 0.05 | |
| Does not live with family | 372 | 0.92 (0.60-1.42) | 0.7 | 0.92 (0.58-1.45) | 0.7 |
| Insurance statusb | 372 | ||||
| Employer group health insurance or privately purchased |
1.16 (0.71-1.89) | 0.5 | 1.49 (0.89-2.48) | 0.1 | |
| Government insurance for the poorc | 0.94 (0.59-1.51) | 0.8 | 0.82 (0.49-1.35) | 0.4 | |
| Diabetes | 370 | 0.30 (0.20-0.45) | <0.001 | 0.36 (0.23-0.54) | <0.001 |
| Congestive heart failure | 370 | 0.47 (0.29-0.77) | 0.003 | 0.77 (0.46-1.28) | 0.3 |
| Peripheral arterial disease | 370 | 0.20 (0.11-0.37) | <0.001 | 0.22 (0.12-0.42) | <0.001 |
| Stroke | 370 | 0.42 (0.20-0.88) | 0.02 | 0.65 (0.30-1.38) | 0.3 |
| enPCR (/0.1 g/kg/d) | 371 | 1.06 (0.99-1.13) | 0.1 | 1.04 (0.96-1.12) | 0.3 |
| Residual renal clearance (/1 mL/min) | 372 | 1.22 (0.74-2.01) | 0.4 | 1.27 (0.75-2.13) | 0.4 |
| Creatinine (/1 mg/dL) | 372 | ||||
| Daily Trial | 1.23 (1.13-1.34) | <0.001 | 1.16 (1.06-1.28) | 0.002 | |
| Nocturnal Trial | 1.02 (0.89-1.16) | 0.8 | 0.99 (0.85-1.16) | 0.9 | |
| Phosphate (/1 mg/dL) | 372 | ||||
| Daily Trial | 1.40 (1.21-1.61) | <0.001 | 1.25 (1.08-1.45) | 0.003 | |
| Nocturnal Trial | 1.02 (0.81-1.28) | 0.9 | 0.98 (0.77-1.24) | 0.8 | |
| Hemoglobin (/1 g/dL) | 346 | 1.05 (0.90-1.23) | 0.5 | 1.05 (0.90-1.24) | 0.5 |
| PTH (/0.1 pg/L) | 364 | 1.76 (1.13-2.93) | 0.9 | 1.68 (1.05-2.86) | 0.9 |
| Albumin (/0.1 g/dL) | 372 | 1.04 (1.00-1.09) | 0.07 | 1.04 (0.99-1.09) | 0.1 |
| Calcium (/1 mg/dL) | 364 | 0.85 (0.69-1.06) | 0.2 | 0.95 (0.76-1.20) | 0.7 |
| Bicarbonate (/1 mmol/L) | 363 | 0.93 (0.88-0.98) | 0.006 | 0.96 (0.91-1.01) | 0.1 |
| LV mass (/10 g) | 349 | 1.01 (0.97-1.05) | 0.7 | 0.97 (0.93-1.01) | 0.2 |
| BMI (/1 kg/m2) | 353 | 0.97 (0.94-0.99) | 0.007 | 0.97 (0.94-1.00) | 0.02 |
| ICW volume/weight (/1 dL/kg) | 351 | 2.97 (2.13-4.15) | <0.001 | 3.88 (2.17-6.93) | <0.001 |
| Phase angle (/0.1°) | 351 | 1.04 (1.03-1.06) | <0.001 | 1.02 (1.01-1.04) | 0.003 |
| Randomly assigned | 375 | 1.37 (0.79-2.41) | 0.3 | 1.53 (0.86-2.72) | 0.1 |
| Nocturnal Trial | 375 | 1.41 (0.91-2.18) | 0.1 | 1.45 (0.92-2.30) | 0.1 |
Note: The Short Physical Performance Battery is a direct measurement of lower-extremity function, measured using: (1) gait speed for a 4-m walk, (2) chair stand with a goal of standing unassisted without use of arms 5 times within 60 seconds, and (3) balance score, which measures the capacity to stand with feet together for 10 seconds. Each exercise was scored from 0-4, with higher scores representing fewer limitations. The Short Physical Performance Battery Score was the sum of these component scores.
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; OR, odds ratio; PTH, parathyroid hormone.
The reference group includes 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.