While the incidence of inflammatory bowel disease (IBD) is stable in the West, it is still rising in several newly industrialized countries, according to Min Zhao, MD, PhD, and other researchers from the Department of Gastroenterology at The First Affiliated Hospital, Sun Yat-Sen University in Guangzhou, China.
Therefore, they conducted a meta-analysis to potentially differentiate environmental and dietary IBD risk factors between Eastern and Western populations. The study’s article, published in Alimentary Pharmacology & Therapeutics, reported several factors that contributed to the development of IBD in both populations, but stated that “certain factors influenced IBD risk differently in these populations.”
The analysis reviewed data from a total of 255 studies using a random effects model. Researchers identified 25 risk factors for IBD, seven of which were shared between Eastern and Western individuals with a family history of Crohn’s disease (CD) or ulcerative colitis (UC): former smoking (CD/UC), smoking (CD), appendicectomy (CD), tonsillectomy (CD), consumption of meat and meat products (CD), and vitamin D deficiency (UC).
The remaining variables, which included urban living, current smoking, antibiotics, oral contraceptives, caesarean section, isotretinoin, total energy, fat, cholesterol, fatty acids and their sub-classifications, eggs, and soft drinks, were only associated with an increased risk of IBD in one of the populations.
Conversely, the researchers identified 21 protective factors for IBD, eight of which were common in the East and West: farm animals (CD/UC), Helicobacter pylori infection (CD/UC), multiple births (CD), physical activity (CD), history of breastfeeding (CD), pets (UC), current smoking (UC), and coffee intake (UC). Additionally, Western and Eastern individuals had 10 and eight protective factors, respectively, against IBD in just their population.
The study’s authors presented their results as evidence that various risk factors have different effects in predisposing an individual to IBD between Eastern and Western populations, indicating the possibility of more personalized care for patients.