Table 5.
Urinary excretion of N1-MN + 2Py, N1-MN, 2Py and 2Py/N1-MN, and dietary intake of niacin equivalents across tertiles of N1-MN + 2Py excretion stratified by sex in KTR 1,2.
| Variable | Tertiles of Sex-Stratified N1-MN + 2Py Excretion | Std. β | p-Value | ||
|---|---|---|---|---|---|
| T1 n = 219 |
T2 n = 221 |
T3 n = 220 |
|||
| Urinary excretion | |||||
| N1-MN + 2Py, μmol/day | 131.5 (110.5–150.9) | 203.6 (181.5–225.6) | 313.8 (274.2–382.8) | - | - |
| N1-MN, μmol/day | 14.7 (10.9–19.4) | 21.5 (17.6–27.7) | 34.7 (26.1–45.3) | 0.74 | <0.001 |
| 2Py, μmol/day | 114.5 (94.0–131.6) | 178.2 (155.6–198.3) | 280.0 (242.1–340.4) | 0.99 | <0.001 |
| 2Py/N1-MN | 7.8 (6.0–9.7) | 8.3 (6.5–10.4) | 8.8 (6.4 –11.5) | −0.16 | <0.001 |
| Dietary intake | |||||
| Niacin equivalents intake, mg/day | 33.1 ± 8.5 | 36.6 ± 9.7 | 36.9 ± 9.1 | 0.18 | <0.001 |
1 Normally distributed, skewed, and nominal data are presented as mean ± SD, median (IQR) and absolute number (percentage), respectively. 2 Cross-sectional associations of urinary excretion of N1-MN, 2Py and 2Py/N1-MN, and dietary intake of niacin equivalents with N1-MN + 2Py excretion were investigated with linear regression analyses, with adjustment for sex, of which std. β and p-value are presented. N1-MN, N1-methylnicotinamide; KTR, kidney transplant recipients; std. β, standardized β; 2Py, N1-methyl-2-pyridone-5-carboxamide; 2Py/N1-MN, ratio of 2Py to N1-MN.