Results
In total 38 participants were included in this study, of whom 19 IBD
walkers, 19 non-IBD walkers. One IBD walker fell during exercise on day
1 and dropped out, he was excluded from all statistical analysis.
Clinical disease characteristics of IBD patients are shown in Table 1.
The IBD study groups consisted of 8 patients with Crohn’s disease and 10
patients with ulcerative colitis. The mean age of diagnosis was 33 ± 13
years. One year before the walking event, a total of 8 (44%) IBD
patients had no flare-ups, 6 patients had one to two flare-ups and 4
patients had three of more flare-ups. Baseline characteristics of both
between the IBD walkers and the age/gender-matched control group are
shown in table 2. The mean age of the study population was 54 ± 12 years
and the average BMI of all participants was 26.0 ± 3.8 kg/m2. In each
group, 11 participants were female. No significant differences were
found between IBD walkers and non-IBD walkers regarding participant
characteristics, except for training distance during the last two weeks
before the walking event (IBD walkers vs non-IBD walkers, p=0.03).
Responsiveness to fMLF, determined by flow cytometric determination of
innate immune markers, is shown in Figure 1. The cellular responsiveness
to fMLF is shown as the Median Fluorescent Intensity(MFI) of innate
immune markers: Neprilysine (CD10) (Figure 1A), Complement receptor 3
(CD11b) (Figure 1C-D) , Complement receptor 1 (CD35) (Figure 1 E-G) and
L-selectin (CD62L) (Figure 1H-J).
Smaller increased responsiveness to fMLF was shown after 3 days of
prolonged exercise in the expression of the activation markers CD11b and
CD35 in IBD walkers compared to non-IBD walkers in neutrophils (p=0.01;
p=0.03) and monocytes (p=0.001; p=0.008). No difference in CD11b and
CD35 expression was demonstrated between the study groups at baseline
measurements. No difference in responsiveness was seen in the cell
adhesion receptor CD62L in neutrophils, monocytes and eosinophils
between the study groups. The maturation/activation marker CD10 showed
similar smaller increased responsiveness to fMLF after 3 days of
repeated prolonged exercise in IBD walkers compared to non-IBD walkers
in neutrophils (p=0.005). However, already at day 0, a lower expression
of CD10 was demonstrated in the neutrophil compartment of IBD walkers
compared to non-IBD walkers (p=0.01).