Global Impact of IBD
Traditionally, inflammatory bowel disease (IBD), comprising ulcerative colitis (UC) and Crohn’s disease (CD), has been regarded as a Western disease.
As more than 2 million Europeans and 1.5 million North Americans have IBD, and it was thought that other regions were spared.
However, studies over the last two decades have shown a rapidly increasing incidence in newly industrialized countries in the Middle East, Asia and South America.
Worldwide, IBD was estimated at 3.32 million cases in 1990, rising to 4.90 million cases in 2019—a 47% increase. This growth is particularly notable in countries like China and the USA, which have the highest number of cases.
The Evolution of IBD Globally
Emergence: In developing countries, IBD is just starting to appear, with only a few sporadic cases being reported.
Acceleration in Incidence: Newly industrialized countries see a sharp increase in IBD cases, but the overall number of people living with the disease (prevalence) remains relatively low.
Compounding Prevalence: Western countries, where IBD was first recognized after the Industrial Revolution, are now in this stage. Here, the number of new cases (incidence) has stabilized, but the total number of people living with IBD (prevalence) is rising quickly due to years of higher incidence and lower mortality.
The Rise of IBD
…can be explained by imagining an open tap filling a sink.
The flow of water from the tap represents incidence—the number of new cases of IBD. The sink holds the water, representing prevalence—the total number of existing cases of IBD.
What’s causing the tap to open wider?
Most researchers agree that the rapid increase in IBD cases worldwide over the past few years cannot be attributed to genetic changes alone, as genetic factors account for only 8.2% of UC and 13.1% of CD cases; instead, this rise is largely due to environmental factors acting on genetically susceptible individuals, triggering immune responses that contribute to the onset and progression of the disease.
Simultaneously, economic advances, like better access to colonoscopies, also help detect more cases.
Together, these factors raise the water level in the sink—the growing number of people with IBD.
Lifestyle and Environmental Factors
that are increasing IBD in genetically predisposed individuals.
Who is Most at Risk of IBD?
IBD affects males and females of all ages, but is more common in:
Adolescents and Young Adults
More common in teens and adulthood, typically between ages 15 and 35.
Immigrants
Studies of migrant populations have shown that the children of individuals who emigrated from regions in Asia with low IBD prevalence to developed countries have a similarly high incidence of IBD, comparable to the children of non-immigrants. This suggests that the risk of IBD may be triggered by early-life exposure to environmental factors in these developed regions.
People with a Family History of IBD
Those with a family history of IBD are at higher risk, though the disease can also appear in people without any family history.
Urbanization/ Westernization
People living in cities are more likely to develop IBD than those in rural areas, due to environmental factors as these regions urbanize and adopt westernized lifestyles.
It’s said…
“Genetics loads the gun, but environment and lifestyle pull the trigger.”
Remember, it’s not your fault that you have IBD. Many factors play a role in its development. However, following a healthy lifestyle alongside your prescribed medication can make a big difference in your recovery journey.
References
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