Which Environmental Factors Cause IBD Relapses?

THE EFFECT OF DAILY PHYSICAL ACTIVITY ON THE ACTIVITY OF INFLAMMATORY BOWEL DISEASES IN THERAPY-FREE PATIENTS

It has been suggested that various environmental factors play a very important role in the etiology of inflammatory bowel diseases (IBDs) and that they have a significant effect on the course of these diseases. The aim of this study was to investigate the effect of daily physical activity on the activity of IBDs in therapy-free patients. This cross-sectional population based study was conducted in eastern Croatia from January to June 2016. The study included 312 patients, mean age 49.9±15.0 years, 53.2% of males and 46.8% of females; there were 63.4% of ulcerative colitis (UC) and 36.6% of Crohn’s disease (CD) patients. Sociodemographic characteristics of patients, data on their daily physical activity and type of therapy taken were collected through a specifically designed and validated questionnaire, while the activity of UC and CD was evaluated using the Mayo index and Harvey-Bradshaw index. The study showed that 24.0% of patients were not taking therapy. Daily physical activity was connected to IBD in study patients when taking both diseases collectively (Fisher exact test; p<0.001), as well as to the inactivity of CD (Fisher exact test; p=0.001) and UC (Fisher exact test; p=0.006), when observing each disease separately. Daily physical activity was connected to the inactivity of IBDs in patients not taking therapy. It is necessary to educate all IBD patients about the importance of physical activity in order to control their disease.

Genetic and environmental factors significant for the presentation and development of inflammatory bowel disease

OBJECTIVES

The aim of the study was to evaluate associations between inflammatory bowel disease (IBD) presentation and variants in NOD2, TLR4, TNF-α, IL-6, IL-1β, and IL-RN genes in order to identify possible environmental factors that may affect IBD occurrence, investigate potential predictors for surgical treatment of IBD, and correlate the presence of granulomas in biopsy specimens with clinical characteristics of Crohn's disease (CD) patients.

PATIENTS AND METHODS

We genotyped 167 IBD patients using PCR-based methodology and tested for disease genotype-phenotype associations.

RESULTS

In CD patients ileal localization of disease was more frequent in NOD2 variant carriers. Ileal CD was associated with IL-6 GC+CC genotypes, identifying C allele as a possible marker of increased risk for ileal CD. In CD patients a positive family history for IBD was related to earlier onset of disease, higher risk for CD-related surgery, and appendectomy. CD patients who are TLR4 299Gly carriers are at higher risk for surgery at onset of the disease compared with TLR4 299Asp variant carriers. The presence of granuloma in biopsy specimens was more frequent in patients in whom a diagnosis of CD was made during emergency surgery. Multivariate analysis showed that CD carriers of the 299Gly allele had a 4.6-fold higher risk for emergency surgery before CD diagnosis is established compared with noncarriers, suggesting an aggressive disease course. Granuloma in endoscopic biopsies is detected 5.4-fold more frequently in patients treated surgically at the time of diagnosis.

CONCLUSION

Genetic variants together with epidemiological and clinical data of IBD patients could potentially be used as predictors of the disease course.