Table 4.
Regression coefficients with 95% confidence intervals for the association of longitudinal GNRI changes with the rates of changes in nutritional parameters (slopes) over 18 months
| Variable | Change per 1-Unit Increase in GNRI | 95% Confidence Interval | ||
|---|---|---|---|---|
| Lower | Upper | P | ||
| Dietary intake | ||||
| DEI (kcal/kg per day) | −0.02 | −0.07 | 0.03 | 0.38 |
| DPI (g/kg per day) | −0.0001 | −0.002 | 0.002 | 0.94 |
| nPNA (g/kg per day) | 0.0007 | −0.002 | 0.003 | 0.56 |
| Biochemical markers | ||||
| Transferrin (mg/dl) | 0.59 | 0.31 | 0.87 | <0.001 |
| Creatinine (mg/dl) | 0.02 | 0.009 | 0.04 | 0.002 |
| Cholesterol (mg/dl) | 0.46 | 0.12 | 0.81 | 0.01 |
| TLC (x103/ml) | 2.17 | −2.94 | 7.27 | 0.40 |
| IL-6 (pg/ml) | −0.62 | −0.87 | −0.37 | <0.001 |
| EPO dosage (×103 U/wk) | −11.80 | −77.97 | 54.02 | 0.72 |
| Anthropometric measurements | ||||
| TSF (mm) | 0.06 | 0.02 | 0.10 | 0.01 |
| MAC (cm) | 0.04 | 0.02 | 0.06 | <0.001 |
| MAMC (cm) | 0.05 | 0.03 | 0.08 | <0.001 |
| Bioimpedance analysis | ||||
| TBW (kg) | 0.03 | −0.0005 | 0.07 | 0.05 |
| ECW (kg) | 0.03 | 0.002 | 0.05 | 0.04 |
| ECW/TBW | 0.0003 | 0.00004 | 0.0006 | 0.05 |
| FM (kg) | 0.21 | 0.16 | 0.26 | <0.001 |
| Body fat (%) | 0.21 | 0.15 | 0.27 | <0.001 |
| FFM (kg) | 0.06 | 0.03 | 0.09 | 0.001 |
| Phase angle (deg) | 0.02 | 0.007 | 0.02 | <0.001 |
All nutritional variables presented above were modeled separately as dependent variables, whereas independent variables included fixed factors (such as age, sex, diabetes status, dialysis vintage, and past cardiovascular disease), and GNRI as a continuous variable. The model takes into account every calculation of GNRI and presents nutritional variables at each time point separately for each patient. Regression coefficients indicate mean longitudinal change in outcome variables associated with a 1-unit longitudinal increase in GNRI, controlling for fixed factors (as mentioned above). GNRI, geriatric nutritional risk index; DEI, daily energy intake; DPI, daily protein intake; nPNA, normalized protein nitrogen appearance; TLC, total lymphocyte count; EPO, erythropoietin; TSF, triceps skinfold thickness; MAC, mid-arm circumference; MAMC, mid-arm muscle circumference calculated; TBW, total body water; ECW, extracellular water; ECW/TBW, extracellular water/total body water ratio; FM, fat mass; FFM, fat free mass.