Table 2.
Regression equations for permeability results. Table 2 shows regression equation for permeability results over age (18–82 years) for all participants and for men only as depicted in Fig. 1. The previously published historic results by Saltzman et al. (1995) were added for comparison. The number of women differed markedly in the three populations: all (43%), men only (0%) and Saltzman (80%). Despite the gender difference the development of permeability values along the age line was similar in all three computations speaking against any sexual dimorphism
| N | Regression equation | RC | P | |
|---|---|---|---|---|
| Permeability index (% lact/% man) | ||||
| All | 215 | 0.019 + 7*10−6*age | 0.01 | 0.85 |
| Men only | 122 | 0.018 + 2*10−5*age | 0.03 | 0.72 |
| Saltzman et al. (1995) | 56 | – | – | – |
| Lactulose (%, urinary recovery) | ||||
| All | 215 | 0.32−0.001*age | 0.12 | 0.09 |
| Men only | 122 | 0.35−0.001*age | 0.15 | 0.09 |
| Saltzman et al. (1995) | 56 | 0.21−0.001*age | 0.23 | 0.09 |
| Mannitol (%, urinary recovery) | ||||
| All | 215 | 18.21−0.06*age | 0.24 | <0.001 |
| Men only | 122 | 20.18−0.09*age | 0.33 | <0.001 |
| Saltzman et al. (1995) | 56 | 14.00−0.06*age | 0.27 | 0.05 |
RC, regression coefficient; % lact/% man, % urinary recovery of lactulose divided by % urinary recovery of mannitol.