Prevalence
Microscopic colitis (MC), in all of its various forms, including lymphocytic colitis, collagenous colitis, mastocytic enterocolitis, and less common forms, has been frequently misunderstood, misdiagnosed, under-diagnosed, and inadequately treated ever since it was first described several decades ago. Even though the inflammation is not readily visible to the naked eye (as is commonly the case with the other inflammatory bowel diseases), microscopic colitis is indeed an inflammatory bowel disease (IBD). And as any patient who has the disease can attest, the symptoms can be just as debilitating as the symptoms of any other IBD. Unfortunately though, microscopic colitis seems to receive only a tiny fraction of the attention devoted to the other types of IBD. This seems remarkable in view of the fact that recent research data suggest that MC is at least as common as Crohn's disease, and much more common than celiac disease. And yet a search of the literature or the Internet will turn up seemingly unlimited sources of information about Crohn’s disease and celiac disease, but comparatively limited detailed and reliable information about MC.
Is MC actually a rare disease, as was initially claimed by the medical community?
Definitely not, according to research data. As early as 2004, data published by Martin Olesen and colleagues showed that the annual incidence of microscopic colitis, in its various forms, is significantly higher than is commonly believed by most medical professionals, and in fact, they found that in Sweden, the annual incidence of microscopic colitis, in its combined forms, matched the incidence of Crohn’s disease, and it approached the incidence of ulcerative colitis.1
A more recent Canadian study, published in 2011, shows that microscopic colitis is even significantly more common than celiac disease.2 The Canadian study showed that the incidence of MC is more than 60 % higher than celiac disease.
The Canadian study also verified that the incidence of MC is increasing at an average annual growth rate of approximately 12 %, which is almost twice as fast as the growth rate of celiac disease. By comparison, celiac disease is claimed to be increasing at about a 7 % average annual rate. This calculated growth rate for celiac disease is based on a study done by the Mayo Clinic, that concluded that the risk of developing celiac disease increased to four times the initial rate, over a 50 year period, beginning in the 1950's.3
So it appears that microscopic colitis may be the most common of all the inflammatory bowel diseases, despite claims by some medical authorities to the contrary. If it isn't now, it soon will be, according to the comparison of growth rates in diagnoses.
Is MC actually a rare disease, as was initially claimed by the medical community?
Definitely not, according to research data. As early as 2004, data published by Martin Olesen and colleagues showed that the annual incidence of microscopic colitis, in its various forms, is significantly higher than is commonly believed by most medical professionals, and in fact, they found that in Sweden, the annual incidence of microscopic colitis, in its combined forms, matched the incidence of Crohn’s disease, and it approached the incidence of ulcerative colitis.1
A more recent Canadian study, published in 2011, shows that microscopic colitis is even significantly more common than celiac disease.2 The Canadian study showed that the incidence of MC is more than 60 % higher than celiac disease.
The Canadian study also verified that the incidence of MC is increasing at an average annual growth rate of approximately 12 %, which is almost twice as fast as the growth rate of celiac disease. By comparison, celiac disease is claimed to be increasing at about a 7 % average annual rate. This calculated growth rate for celiac disease is based on a study done by the Mayo Clinic, that concluded that the risk of developing celiac disease increased to four times the initial rate, over a 50 year period, beginning in the 1950's.3
So it appears that microscopic colitis may be the most common of all the inflammatory bowel diseases, despite claims by some medical authorities to the contrary. If it isn't now, it soon will be, according to the comparison of growth rates in diagnoses.
1. Olesen, M., Eriksson, S., Bohr, J., Järnerot, G., & Tysk, C. (2004). Microscopic colitis: A common diarrhoeal disease. An epidemiological study in Örebro, Sweden, 1993–1998. Gut, 53(1), 346–350. http://gut.bmj.com/content/53/3/346.long
2. Stewart, M., Andrews, C. N., Urbanski, S., Beck, P. L., & Storr, M. (2011). The association of coeliac disease and microscopic colitis: A large population-based study. Alimentary Pharmacology & Therapeutics, 33(12), 1340–1349. http://www.medscape.com/viewarticle/743426?src=mp&spon=20
3. Toman, B. (2010, July). Celiac Disease: On the Rise. Mayo Clinic's Online Research Magazine. http://discoverysedge.mayo.edu/celiac-disease/
2. Stewart, M., Andrews, C. N., Urbanski, S., Beck, P. L., & Storr, M. (2011). The association of coeliac disease and microscopic colitis: A large population-based study. Alimentary Pharmacology & Therapeutics, 33(12), 1340–1349. http://www.medscape.com/viewarticle/743426?src=mp&spon=20
3. Toman, B. (2010, July). Celiac Disease: On the Rise. Mayo Clinic's Online Research Magazine. http://discoverysedge.mayo.edu/celiac-disease/