The four epidemiological stages in the global evolution of inflammatory bowel disease

In the paper

“Initially, the incidence was low and flat (0.27 and 0.09 per 100,000 in 1933 and 1943, respectively), but showed a spike towards the 1980s (0.98 per 100,000 in 1953, 2.4 per 100,000 in 1963, 5.2 per 100,000 in 1973 and 9.1 per 100,000 in 1983). Thereafter, the incidence stabilized (6.0 per 100,000 in 1993 and 7.0 per 100,000 in 2003)29–31.”

What the sources say

• Partly supported

  The Introduction and Discussion report a Cardiff peak in the early 1980s, supporting the broad historical pattern. Table 2 gives decade-average rates near 6 and 7 per 100,000 for 1986–1995 and 1996–2005, but does not establish the claimed rates for 1993 and 2003 specifically. The Discussion says incidence continued to rise slowly rather than stabilizing. (LLM, conf=0.86)

  cites [29] Gunesh, S., Thomas, G. A., Williams, G. T., Roberts, A. & Hawthorne, A. B. The incidence of Crohn’s disease in Cardiff over the last 75 years: an update for 1996–2005. Aliment. Pharmacol. Ther. 27, 211–219 (2008). sourceExperimental — accuracy not yet measured
• Partly supported

  The Results report a low incidence in the 1930s and a rise through the 1970s, from 0.18 per 100,000 per year in 1931–35 to 4.83 in 1971–75. The study covers only 1934–77, so it cannot support the claimed 1983 spike or stabilization in 1993 and 2003; it also does not establish that incidence was flat in the early decades. (LLM, conf=0.91)

  cites [30] Mayberry, J., Rhodes, J. & Hughes, L. E. Incidence of Crohn’s disease in Cardiff between 1934–1977. Gut 20, 602–608 (1979). sourceExperimental — accuracy not yet measured
• Partly supported

  The Results report low incidence in the 1930s and a rise to 8.3 per 100,000 per year in 1981–1985. The paper does not give the claimed 9.1 figure for 1983, and its data end in 1985, so it cannot support the 1993 and 2003 figures or the subsequent stabilization. (LLM, conf=0.88)

  cites [31] Rose, J. D., Roberts, G. M., Williams, G., Mayberry, J. F. & Rhodes, J. Cardiff Crohn’s disease jubilee: the incidence over 50 years. Gut 29, 346–351 (1988). sourceExperimental — accuracy not yet measured

In the paper

“For example, in Canada, 0.51% prevalence of IBD in 2008 represented 169,564 individuals with IBD, whereas 402,853 individuals are predicted to be living with IBD in 2030 — a 238% increase from 2008.”

In the paper

“In 2020, developing countries are in the Emergence stage, newly industrialized countries are in the Acceleration in Incidence stage, and Western regions are in the Compounding Prevalence stage.”

In the paper

“By combining epidemiological principles with temporal prevalence trends, a fourth stage can be postulated: Prevalence Equilibrium, the countervailing force between the increasing mortality of an ageing IBD population and the incidence of IBD (Fig. 1).”

In the paper

“By the 1950s, ulcerative colitis and Crohn’s disease were established in the Western world, which was then in the process of shifting to the second epidemiological stage in the evolution of IBD.”

In the paper

“Since 2000 (that is, the end of the second stage within the Western world), the Coalescing Incidence Ranges of Crohn’s disease and ulcerative colitis were 6–11 per 100,000 and 6–15 per 100,000, respectively (12–26 per 100,000 collectively) in the Western world (Fig. 2).”

What the sources say

• Not checked yetcites [4] Ng, S. C. et al. Worldwide incidence and prevalence of inflammatory bowel disease in the 21st century: a systematic review of population-based studies. Lancet 390, 2769–2778 (2018). source

In the paper

“This stage is associated with rapidly rising incidence and low prevalence.”

In the paper

“The investigators articulated an elegant argument that the increased incidence of IBD in the Faroe Islands is not simply an artefact of improved awareness, diagnosis and data capture44.”

What the sources say

• Not checked yetcites [44] Hammer, T., Nielsen, K. R., Munkholm, P., Burisch, J. & Lynge, E. The Faroese IBD study: incidence of inflammatory bowel diseases across 54 years of population-based data. J. Crohns Colitis. 10, 934–942 (2016). source

In the paper

“By contrast, recognition of IBD in the first half of the twentieth century in developing countries of the time lagged behind that in the Western world”

• Also stated in: § Stage one: Emergence of IBD · plain

  “The emergence of IBD in Asia and Latin America occurred later in the twentieth century.”

What the sources say

• Not checked yetcites [21] Chopra, R. N. & Ray, P. N. Chronic ulcerative colitis. Ind. Med. Gaz. 74, 65–74 (1939).
• Not checked yetcites [2] Kaplan, G. G. & Ng, S. C. Globalisation of inflammatory bowel disease: perspectives from the evolution of inflammatory bowel disease in the UK and China. Lancet Gastroenterol. Hepatol. 1, 307–316 (2016). source
• Not checked yetcites [22] Jiang, X. L. & Cui, H. F. An analysis of 10218 ulcerative colitis cases in China. World J. Gastroenterol. 8, 158–161 (2002). source

In the paper

“Inflammatory bowel disease (IBD) is a global disease; its evolution can be stratified into four epidemiological stages: Emergence, Acceleration in Incidence, Compounding Prevalence and Prevalence Equilibrium.”

In the paper

“Whereas the incidence of IBD in the Western world increased in the twentieth century, the incidence began to increase in newly industrialized countries at the turn of the twenty-first century4.”

What the sources say

• Not checked yetcites [4] Ng, S. C. et al. Worldwide incidence and prevalence of inflammatory bowel disease in the 21st century: a systematic review of population-based studies. Lancet 390, 2769–2778 (2018). source

In the paper

“For Crohn’s disease, the Ceiling Incidence Range is in the range 23.8–29.3 per 100,000 (refs4,40,43), and for ulcerative colitis, it is in the range 23.1–57.9 per 100,000 (refs4,43,44).”

What the sources say

• Not checked yetcites [4] Ng, S. C. et al. Worldwide incidence and prevalence of inflammatory bowel disease in the 21st century: a systematic review of population-based studies. Lancet 390, 2769–2778 (2018). source
• Not checked yetcites [40] Su, H. Y., Gupta, V., Day, A. S. & Gearry, R. B. Rising incidence of inflammatory bowel disease in Canterbury, New Zealand. Inflamm. Bowel Dis. 22, 2238–2244 (2016). source
• Not checked yetcites [43] Leddin, D., Tamim, H. & Levy, A. R. Decreasing incidence of inflammatory bowel disease in eastern Canada: a population database study. BMC Gastroenterol. 14, 140 (2014). source
• Not checked yetcites [44] Hammer, T., Nielsen, K. R., Munkholm, P., Burisch, J. & Lynge, E. The Faroese IBD study: incidence of inflammatory bowel diseases across 54 years of population-based data. J. Crohns Colitis. 10, 934–942 (2016). source

In the paper

“The journey from a few sporadic cases of inflammatory bowel disease (IBD) to millions of people with IBD is a 250-year path beginning with the industrial revolution1.”

What the sources say

• Not checked yetcites [1] Kaplan, G. G. The global burden of IBD: from 2015 to 2025. Nat. Rev. Gastroenterol. Hepatol. 12, 720–727 (2015). source

In the paper

“In this milieu, IBD emerged in the Western world, starting as a handful of case studies published at the end of the eighteenth century to taking root as a new affliction of health2.”

What the sources say

• Not checked yetcites [2] Kaplan, G. G. & Ng, S. C. Globalisation of inflammatory bowel disease: perspectives from the evolution of inflammatory bowel disease in the UK and China. Lancet Gastroenterol. Hepatol. 1, 307–316 (2016). source

In the paper

“the annual incidence of IBD in Bahrain increased from an average of 3 per 100,000 to 12 per 100,000 during the period 1984–2014, but the total prevalent population remained under 200 persons at 26 per 100,000 (0.026%) (ref.47).”

What the sources say

• Not checked yetcites [47] Abdulla, M. et al. Inflammatory bowel disease in Bahrain: single-center experience. Clin. Exp. Gastroenterol. 10, 133–145 (2017). source

In the paper

“Furthermore, incidence continues to increase in certain countries including New Zealand40 and some countries/regions in Europe, such as Spain41 and Denmark42.”

What the sources say

• Not checked yetcites [40] Su, H. Y., Gupta, V., Day, A. S. & Gearry, R. B. Rising incidence of inflammatory bowel disease in Canterbury, New Zealand. Inflamm. Bowel Dis. 22, 2238–2244 (2016). source
• Not checked yetcites [41] Chaaro Benallal, D. et al. Evolution of the incidence of inflammatory bowel disease in Southern Spain. Rev. Esp. Enferm. Dig. 109, 757–760 (2017).
• Not checked yetcites [42] Lophaven, S. N., Lynge, E. & Burisch, J. The incidence of inflammatory bowel disease in Denmark 1980–2013: a nationwide cohort study. Aliment. Pharmacol. Ther. 45, 961–972 (2017). source

In the paper

“The Ceiling Incidence Range needs to be interpreted cautiously because outliers can represent unique clinical scenarios or methodological biases that skew the incidence range upwards.”

In the paper

“a four-decade analysis of the incidence of IBD in Malaysia showed a slow increase from the 1980s (0.36 per 100,000), to the 1990s (0.48 per 100,000) and to the 2000s (0.63 per 100,000), and then more than doubling to 1.46 per 100,000 in the past decade (2010–2018); however, the prevalence of IBD in Malaysia remained low at 23 per 100,000 (0.023%) in 2018 (ref.48).”

What the sources say

• Not checked yetcites [48] Mokhtar, N. M. et al. A four-decade analysis of the incidence trends, sociodemographic and clinical characteristics of inflammatory bowel disease patients at single tertiary centre, Kuala Lumpur, Malaysia. BMC Public Health 19, 550 (2019). source

In the paper

“In many regions in the Western world, the rapidly increasing incidence of IBD levelled off in the last decades of the twentieth century and, in some regions, reduced at the turn of the twenty-first century.”

What the sources say

• Not checked yetcites [4] Ng, S. C. et al. Worldwide incidence and prevalence of inflammatory bowel disease in the 21st century: a systematic review of population-based studies. Lancet 390, 2769–2778 (2018). source

In the paper

“in southern Spain, the incidence of IBD increased from 3.5 per 100,000 in 1995–2000 to 14.7 per 100,000 in 2001–2014, which is still lower than most reported incidence values in the Western world, for which the mean incidence for the period 2001–2014 was 1.4 times higher (19.77 per 100,000)41.”

What the sources say

• Not checked yetcites [41] Chaaro Benallal, D. et al. Evolution of the incidence of inflammatory bowel disease in Southern Spain. Rev. Esp. Enferm. Dig. 109, 757–760 (2017).

In the paper

“By contrast, the Danish territory of the Faroe Islands had the highest worldwide average annual incidence of IBD at 84.2 per 100,000 in 2011, with a predominance of ulcerative colitis44.”

What the sources say

• Not checked yetcites [44] Hammer, T., Nielsen, K. R., Munkholm, P., Burisch, J. & Lynge, E. The Faroese IBD study: incidence of inflammatory bowel diseases across 54 years of population-based data. J. Crohns Colitis. 10, 934–942 (2016). source

In the paper

“As most countries in the Western world transitioned into the third stage in the evolution of IBD at the end of the twentieth century, newly industrialized countries in Asia and Latin America entered the second stage: the Acceleration in Incidence.”

In the paper

“Moreover, a systematic review of clinical and epidemiological studies on IBD from Latin America documented the emergence of IBD in the twentieth century with a rapidly rising incidence during the twenty-first century49.”

What the sources say

• Not checked yetcites [49] Kotze, P. G. et al. Progression of inflammatory bowel diseases throughout Latin America and the Caribbean: a systematic review. Clin. Gastroenterol. Hepatol. 18, 304–312 (2020). source

In the paper

“In 2008, the calculated prevalence of IBD in Canada and Scotland was 0.51%70 and 0.57%69, respectively, which was similar to the 0.53% reported in Olmsted County in 2011 (ref.28).”

What the sources say

• Not checked yetcites [70] Coward S. Forecasting the Future: A Trek through the Changing Landscape of Inflammatory Bowel Disease. Thesis, Univ. Calgary (2019).
• Not checked yetcites [69] Jones, G. R. et al. IBD prevalence in Lothian, Scotland, derived by capture-recapture methodology. Gut 68, 1953–1960 (2019). source
• Not checked yetcites [28] Shivashankar, R., Tremaine, W. J., Harmsen, W. S. & Loftus, E. V. Jr. Incidence and prevalence of Crohn’s disease and ulcerative colitis in Olmsted county, Minnesota from 1970 through 2010. Clin. Gastroenterol. Hepatol. 15, 857–863 (2017). source

In the paper

“Collectively, these factors reveal the incidence of IBD and, over time, the reported incidence steadily increases.”

In the paper

“In 2011, the prevalence of IBD was 533 per 100,000 in Olmsted County, and therefore almost doubled again in the 20 years from 1991 (ref.28).”

What the sources say

• Not checked yetcites [28] Shivashankar, R., Tremaine, W. J., Harmsen, W. S. & Loftus, E. V. Jr. Incidence and prevalence of Crohn’s disease and ulcerative colitis in Olmsted county, Minnesota from 1970 through 2010. Clin. Gastroenterol. Hepatol. 15, 857–863 (2017). source

In the paper

“Without a cure, and owing to relatively low mortality, patients with IBD diagnosed at a young age can live a long life63.”

What the sources say

• Not checked yetcites [63] Bitton, A., Vutcovici, M., Sewitch, M., Suissa, S. & Brassard, P. Mortality trends in Crohn’s disease and ulcerative colitis: a population-based study in Quebec, Canada. Inflamm. Bowel Dis. 22, 416–423 (2016). source

In the paper

“Moreover, life expectancy has increased with advances in public health and innovations in medicine74.”

What the sources say

• Not checked yetcites [74] Appleby, J. How long can we expect to live? BMJ 346, f331 (2013). source

In the paper

“Population-based epidemiological studies from Canada and Scotland published in 2019 documented the Compounding Prevalence of IBD: during the twenty-first century, prevalence rose by 3% and 4% per year in Canada and Scotland, respectively9,69.”

What the sources say

• Not checked yetcites [9] Coward, S. et al. Past and future burden of inflammatory bowel diseases based on modeling of population-based data. Gastroenterology 156, 1345–1353 (2019). source
• Not checked yetcites [69] Jones, G. R. et al. IBD prevalence in Lothian, Scotland, derived by capture-recapture methodology. Gut 68, 1953–1960 (2019). source

In the paper

“In 2030, this generation will be aged 66–84 years, meaning that nearly one in five people living in the Western world will be over the age of 65 years71.”

What the sources say

• Not checked yetcites [71] Knickman, J. R. & Snell, E. K. The 2030 problem: caring for aging baby boomers. Health Serv. Res. 37, 849–884 (2002). source

In the paper

“in the state of São Paulo, Brazil, the incidence of IBD was 1.0 per 100,000 during the period 1986–1990 (ref.50) and peaked at 13.3 per 100,000 during the period 2012–2015, but the prevalence remained low at 22.6 per 100,000 (2001–2005)51.”

What the sources say

• Not checked yetcites [50] Victoria, C. R., Sassak, L. Y. & Nunes, H. R. Incidence and prevalence rates of inflammatory bowel diseases, in midwestern of Sao Paulo State, Brazil. Arq. Gastroenterol. 46, 20–25 (2009). source
• Not checked yetcites [51] Gasparini, R. G., Sassaki, L. Y. & Saad-Hossne, R. Inflammatory bowel disease epidemiology in Sao Paulo State, Brazil. Clin. Exp. Gastroenterol. 11, 423–429 (2018). source

In the paper

“Forecasting models indicate that the prevalence doubling point of 1% would occur over 22 years in Canada (2008 to 2030)9 and 20 years in Scotland (2008 to 2028)69.”

What the sources say

• Not checked yetcites [9] Coward, S. et al. Past and future burden of inflammatory bowel diseases based on modeling of population-based data. Gastroenterology 156, 1345–1353 (2019). source
• Not checked yetcites [69] Jones, G. R. et al. IBD prevalence in Lothian, Scotland, derived by capture-recapture methodology. Gut 68, 1953–1960 (2019). source

In the paper

“The Unmasking of Incidence is essentially a diagnostic bias: more new cases of IBD are diagnosed as the ability to detect IBD improves.”

In the paper

“the incidence of IBD (2011–2013) was a low 0.43 per 100,000 in the Philippines as compared with 2.98 per 100,000 in Hong Kong53. Furthermore, within nine separate regions in mainland China, the incidence varied from 0.54 per 100,000 in Xi’an to 3.64 per 100,000 in Guangzhou53.”

What the sources say

• Not checked yetcites [53] Ng, S. C. et al. Population density and risk of inflammatory bowel disease: a prospective population-based study in 13 countries or regions in Asia-Pacific. Am. J. Gastroenterol. 114, 107–115 (2019). source

In the paper

“in Malaysia the ulcerative colitis to Crohn’s disease ratio was 5:1 in the 1980s and fell to 1.7:1 from 2010 to 2018 (ref.48).”

What the sources say

• Not checked yetcites [48] Mokhtar, N. M. et al. A four-decade analysis of the incidence trends, sociodemographic and clinical characteristics of inflammatory bowel disease patients at single tertiary centre, Kuala Lumpur, Malaysia. BMC Public Health 19, 550 (2019). source

In the paper

“Inhabitants in these urban environments have been exposed to westernization of their society including diets containing higher levels of fat and refined sugars and changes in lifestyle behaviours, such as an increase in smoking, less breastfeeding, greater exposure to antibiotics and improved hygiene and sanitation56.”

What the sources say

• Not checked yetcites [56] Ng, S. C. et al. Environmental risk factors in inflammatory bowel disease: a population-based case-control study in Asia-Pacific. Gut 64, 1063–1071 (2015). source

In the paper

“Consequently, estimating average disease duration over the course of a lifetime is not feasible in IBD; that is, the prevalence of IBD cannot be estimated by multiplying incidence by average disease duration.”

In the paper

“In the third epidemiological stage, the ‘tug-of-war’ between incidence and mortality greatly favours incidence, and so prevalence increases.”

In the paper

“Historically, IBD typically emerges in a population as cases of ulcerative colitis, eventually followed by cases of Crohn’s disease. Over time, Crohn’s disease becomes more commonly diagnosed as the incidence approximates and, in some cases, surpasses that of ulcerative colitis49.”

What the sources say

• Not checked yetcites [49] Kotze, P. G. et al. Progression of inflammatory bowel diseases throughout Latin America and the Caribbean: a systematic review. Clin. Gastroenterol. Hepatol. 18, 304–312 (2020). source

In the paper

“The diagnosis of IBD is skewed towards ulcerative colitis in lower income regions with limited technology (for example, access only to sigmoidoscopy); however, as economies improve, so too does health-care infrastructure (for example, access to specialists and colonoscopy), which improves the ability of physicians to accurately diagnose Crohn’s disease49.”

What the sources say

• Not checked yetcites [49] Kotze, P. G. et al. Progression of inflammatory bowel diseases throughout Latin America and the Caribbean: a systematic review. Clin. Gastroenterol. Hepatol. 18, 304–312 (2020). source

In the paper

“During the second half of the twentieth century, incidence rapidly rose in the Western world, but prevalence remained relatively low (that is, second epidemiological stage).”

In the paper

“Although prevalence is anticipated to increase over the next decade, as regions transition to the fourth stage, the steep slope of prevalence will decline, leading to a lengthening of the prevalence doubling time.”

In the paper

“The Western world is in the third epidemiological stage (Compounding Prevalence), and is anticipated to cross towards Prevalence Equilibrium within the next 30 years.”

In the paper

“However, IBD can, and does, manifest among individuals from developing countries.”

What the sources say

• Not checked yetcites [66] Benchimol, E. I. et al. Inflammatory bowel disease in immigrants to Canada and their children: a population-based cohort study. Am. J. Gastroenterol. 110, 553–563 (2015). source
• Not checked yetcites [81] Bar-Gil Shitrit, A. et al. Inflammatory bowel disease: an emergent disease among Ethiopian Jews migrating to Israel. Inflamm. Bowel Dis. 21, 631–635 (2015). source

In the paper

“By contrast, in South Korea, which began westernizing earlier, the prevalence of IBD was 57.37 per 100,000 in 2009, but had not quite doubled to 95.59 per 100,000 in 2016, suggesting a Prevalence Doubling Period closer to 10 years79.”

What the sources say

• Not checked yetcites [79] Kwak, M. S. et al. Emerging trends of inflammatory bowel disease in South Korea: a nationwide population-based study. J. Gastroenterol. Hepatol. 34, 1018–1026 (2019). source

In the paper

“Moreover, Prevalence Equilibrium might result in a decline in prevalence in certain jurisdictions, which would reduce the overall burden of IBD to society.”

In the paper

“If the prevalence of IBD follows a similar trend in regions such as India and China with populations of more than one billion people57,89, Asia alone might have more cases of IBD than the Western world before 2050 (ref.1).”

What the sources say

• Not checked yetcites [57] Kedia, S. & Ahuja, V. Epidemiology of inflammatory bowel disease in India: the great shift east. Inflamm. Intest. Dis. 2, 102–115 (2017). source
• Not checked yetcites [89] Ye, L., Cao, Q. & Cheng, J. Review of inflammatory bowel disease in China. ScientificWorldJournal 2013, 296470 (2013). source
• Not checked yetcites [1] Kaplan, G. G. The global burden of IBD: from 2015 to 2025. Nat. Rev. Gastroenterol. Hepatol. 12, 720–727 (2015). source

In the paper

“Over the next decade, gastroenterologists involved in adult care will contend with an escalation in the number of patients living with IBD while simultaneously managing an ageing population that will have a mixture of complications of longstanding IBD and age-related comorbidities.”

In the paper

“This second indicator of the Prevalence Equilibrium will be seen in future studies that will document prevalence not rising by an anticipated 50% within a period of 10–12.5 years.”

In the paper

“As the IBD population ages, their mortality increases and, in conjunction with stable (and even more so with declining) incidence, the steep positive slope indicative of Compounding Prevalence will eventually become more moderate until the point where prevalence levels off, and potentially declines thereafter.”

In the paper

“For example, Japan and South Korea experienced rapid industrialization after World War II and transitioned into the second stage earlier than other countries in Asia55,84.”

What the sources say

• Not checked yetcites [55] Mak, W. Y., Zhao, M., Ng, S. C. & Burisch, J. The epidemiology of inflammatory bowel disease: East meets west. J. Gastroenterol. Hepatol. 35, 380–389 (2020). source
• Not checked yetcites [84] Ng, W. K., Wong, S. H. & Ng, S. C. Changing epidemiological trends of inflammatory bowel disease in Asia. Intest. Res. 14, 111–119 (2016). source

In the paper

“For example, in Taiwan, IBD prevalence doubled from 4.54 per 100,000 in 2001–2005 to 9.39 per 100,000 in 2006–2010 but was just short of doubling again in 2011–2015, suggesting a roughly 5-year Prevalence Doubling Period78.”

What the sources say

• Not checked yetcites [78] Yen, H. H. et al. Epidemiological trend in inflammatory bowel disease in Taiwan from 2001 to 2015: a nationwide populationbased study. Intest. Res. 17, 54–62 (2019). source

In the paper

“Older individuals with IBD will continue to make up a higher proportion of the adult patients attending gastroenterology clinics (that is, with EWAR-IBD exceeding 0.5) and octogenarians with IBD will become more common.”

In the paper

“The Western world will transition to Prevalence Equilibrium stage (stabilization of prevalence) owing to the advancing age of the IBD population as denoted by the ratio of the prevalence among older individuals (aged >64 years) to the prevalence among the working-age population (aged 15–64 years).”

In the paper

“Developing countries are currently in the first stage of evolution (Emergence) and can expect to transition to the second stage if their economies advance and their societies westernize.”

In the paper

“By contrast, newly industrialized countries that are undergoing rapid increases in incidence currently show very short Prevalence Doubling Periods, which extend as the regions get nearer to stage 3.”

In the paper

“Most newly industrialized countries are entrenched in the second stage (Acceleration in Incidence), but if these regions follow the epidemiological patterns of the Western world, they are likely to transition into the third stage over the next three decades.”

In the paper

“Among people over the age of 60 years who were reported in SECURE-IBD, 20% experienced a severe complication of COVID-19, with older age (adjusted OR 1.04, 95% CI 1.01–1.06) and two or more comorbidities (adjusted OR 2.9, 95% CI 1.1–1.78) associated with poor outcomes.”

What the sources say

• Not checked yetcites [97] Brenner, E. J. et al. Corticosteroids, but not TNF antagonists, are associated with adverse COVID-19 outcomes in patients with inflammatory bowel diseases: results from an international registry. Gastroenterology 159, 481–491 (2020). source

In the paper

“Every region in the world is currently in one of the first three epidemiological stages of IBD evolution and, with time, will transition through all four stages1 (Fig. 4).”

What the sources say

• Not checked yetcites [1] Kaplan, G. G. The global burden of IBD: from 2015 to 2025. Nat. Rev. Gastroenterol. Hepatol. 12, 720–727 (2015). source

In the paper

“A fundamental discovery that leads to a cure for IBD would dramatically decrease its incidence.”

In the paper

“Although the Prevalence Equilibrium stage is conjectural, several signs are indicative of its arrival: decline in the slope of prevalence over time; prolongation of the Prevalence Doubling Period; and an elevated ratio of the prevalence of IBD among older individuals to the prevalence among the working-age population (elderly to working-age ratio; EWAR-IBD).”

In the paper

“Consequently, individuals with newly diagnosed IBD will continue to add to the prevalent population, which will continue to drive Compounding Prevalence over the next decade, with prevalence forecast to be 1% by 2030 (ref.9).”

What the sources say

• Not checked yetcites [9] Coward, S. et al. Past and future burden of inflammatory bowel diseases based on modeling of population-based data. Gastroenterology 156, 1345–1353 (2019). source

In the paper

“The ageing IBD population will have reduced life expectancy from age-related comorbidities such as cardiovascular disease and cancer, as well as a small increased risk of death of patients with IBD as compared with age-matched individuals without IBD as controls63,76.”

What the sources say

• Not checked yetcites [63] Bitton, A., Vutcovici, M., Sewitch, M., Suissa, S. & Brassard, P. Mortality trends in Crohn’s disease and ulcerative colitis: a population-based study in Quebec, Canada. Inflamm. Bowel Dis. 22, 416–423 (2016). source
• Not checked yetcites [76] Bernstein, C. N., Nugent, Z., Targownik, L. E., Singh, H. & Lix, L. M. Predictors and risks for death in a population-based study of persons with IBD in Manitoba. Gut 64, 1403–1411 (2015). source

In the paper

“Moreover, after several decades of accelerated incidence, prevalence will begin to climb rapidly as these regions enter the Compounding Prevalence stage, similar to the experience in the Western world at the turn of the twenty-first century.”

In the paper

“A nationwide study in Japan demonstrated a prevalence of IBD of 24 per 100,000 in 1991 (ref.85), which increased to 76 per 100,000 in 2003–2005 (ref.86) and to 228.5 per 100,000 in 2014 (ref.87).”

What the sources say

• Not checked yetcites [85] Morita, N. et al. Incidence and prevalence of inflammatory bowel disease in Japan: nationwide epidemiological survey during the year 1991. J. Gastroenterol. 30 (Suppl. 8), 1–4 (1995).
• Not checked yetcites [86] Asakura, K. et al. Prevalence of ulcerative colitis and Crohn’s disease in Japan. J. Gastroenterol. 44, 659–665 (2009). source
• Not checked yetcites [87] Murakami, Y. et al. Estimated prevalence of ulcerative colitis and Crohn’s disease in Japan in 2014: an analysis of a nationwide survey. J. Gastroenterol. 54, 1070–1077 (2019). source

In the paper

“Newly industrialized countries in Asia and Latin America that are embedded in the second epidemiological stage are currently (in 2020) experiencing a juxtaposition of rapidly rising incidence with low prevalence.”

In the paper

“Similarly, the prevalence of IBD in South Korea was 42 per 100,000 in 2005 (ref.88), 63.8 per 100,000 in 2010 and 92.8 per 100,000 in 2015 (ref.79).”

What the sources say

• Not checked yetcites [88] Yang, S. K. et al. Epidemiology of inflammatory bowel disease in the Songpa-Kangdong district, Seoul, Korea, 1986–2005: a KASID study. Inflamm. Bowel Dis. 14, 542–549 (2008). source
• Not checked yetcites [79] Kwak, M. S. et al. Emerging trends of inflammatory bowel disease in South Korea: a nationwide population-based study. J. Gastroenterol. Hepatol. 34, 1018–1026 (2019). source

In the paper

“Acceleration in Incidence is driven by the Unmasking of Incidence, in which economic advance improves detection of IBD, and the True Rise of Incidence occurs owing to westernization of society.”