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

May combine two claims.

In Canada, 0.51% IBD prevalence in 2008 corresponded to 169,564 patients, while 402,853 are predicted for 2030, a 238% rise from 2008.

“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.”

Probably not a substantial claim: may not pass S4 (based). May combine two claims.

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 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.”

• AssumptionRests on an assumption: Reported incidence and prevalence values from different countries and regions are comparable enough to be combined into a single global staging framework.

May combine two claims.

A fourth stage, Prevalence Equilibrium, can be postulated as the balance between increasing mortality in an ageing IBD population and ongoing incidence; it has not yet occurred but provides a framework for predicting future global burden.

“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).”

May combine two claims.

By the 1950s, ulcerative colitis and Crohn's disease were established in the Western world, which was shifting to the second epidemiological stage.

“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.”

May combine two claims.

Since 2000, the Coalescing Incidence Range in the Western world was 6-11 per 100,000 for Crohn's disease and 6-15 per 100,000 for ulcerative colitis, or 12-26 per 100,000 collectively.

“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).”

• cites [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). sourceNot checked yet

  Not checked in the free run.

• AssumptionRests on an assumption: Reported incidence and prevalence values from different countries and regions are comparable enough to be combined into a single global staging framework.

May combine two claims.

The second stage in newly industrialized countries is associated with rapidly rising incidence and low prevalence.

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

Probably not a substantial claim: may not pass S3 (load-bearing).

The increased incidence of IBD in the Faroe Islands is not simply an artefact of improved awareness, diagnosis, and data capture.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Recognition of IBD in developing countries lagged behind the Western world in the first half of the twentieth century, and IBD emergence in Asia and Latin America occurred later in the twentieth century.

“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.”

• cites [21] Chopra, R. N. & Ray, P. N. Chronic ulcerative colitis. Ind. Med. Gaz. 74, 65–74 (1939).Not checked yet

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• cites [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). sourceNot checked yet

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• cites [22] Jiang, X. L. & Cui, H. F. An analysis of 10218 ulcerative colitis cases in China. World J. Gastroenterol. 8, 158–161 (2002). sourceNot checked yet

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May combine two claims.

IBD is a global disease whose evolution can be divided into four epidemiological stages: Emergence, Acceleration in Incidence, Compounding Prevalence, and Prevalence Equilibrium.

“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.”

May combine two claims.

IBD incidence increased in the Western world during the twentieth century, and began to increase in newly industrialized countries around the start of the twenty-first century.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

The Ceiling Incidence Range in the Western world is 23.8-29.3 per 100,000 for Crohn's disease and 23.1-57.9 per 100,000 for ulcerative colitis.

“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).”

• cites [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). sourceNot checked yet

  Not checked in the free run.

• cites [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). sourceNot checked yet

  Not checked in the free run.

• cites [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). sourceNot checked yet

  Not checked in the free run.

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

The path from a few sporadic IBD cases to millions of people spans about 250 years and began with the industrial revolution.

“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.”

• cites [1] Kaplan, G. G. The global burden of IBD: from 2015 to 2025. Nat. Rev. Gastroenterol. Hepatol. 12, 720–727 (2015). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

In Cardiff, Wales, Crohn's disease incidence was low and flat in the 1930s and 1940s, spiked to 9.1 per 100,000 in 1983, and then stabilized at 6.0 per 100,000 in 1993 and 7.0 per 100,000 in 2003.

“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.”

• 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). sourceNot checked yet

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• cites [30] Mayberry, J., Rhodes, J. & Hughes, L. E. Incidence of Crohn’s disease in Cardiff between 1934–1977. Gut 20, 602–608 (1979). sourceNot checked yet

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• 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). sourceNot checked yet

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May combine two claims.

IBD emerged in the Western world, beginning as a few case studies at the end of the eighteenth century and becoming recognized as a new disease.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

In Bahrain, annual IBD incidence increased from an average of 3 per 100,000 to 12 per 100,000 during 1984-2014, while the total prevalent population remained under 200 persons at 26 per 100,000.

“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).”

• cites [47] Abdulla, M. et al. Inflammatory bowel disease in Bahrain: single-center experience. Clin. Exp. Gastroenterol. 10, 133–145 (2017). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Incidence continues to increase in certain countries including New Zealand and some European regions such as Spain and Denmark.

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

• cites [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). sourceNot checked yet

  Not checked in the free run.

• cites [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 yet

  Not checked in the free run.

• cites [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). sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

The Ceiling Incidence Range must be interpreted cautiously because outliers can reflect unique clinical scenarios or methodological biases that skew the range upwards.

“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.”

May combine two claims.

In Malaysia, IBD incidence increased from 0.36 per 100,000 in the 1980s to 1.46 per 100,000 in 2010-2018, while prevalence remained low at 23 per 100,000 in 2018.

“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).”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

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

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

In southern Spain, IBD incidence increased from 3.5 per 100,000 in 1995-2000 to 14.7 per 100,000 in 2001-2014, which remains lower than most Western incidence values; the mean Western incidence for 2001-2014 was 19.77 per 100,000, 1.4 times higher.

“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.”

• cites [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 yet

  Not checked in the free run.

May combine two claims.

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 colitis.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

As most Western countries transitioned to the third stage at the end of the twentieth century, newly industrialized countries in Asia and Latin America entered the second stage, Acceleration in Incidence.

“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.”

• AssumptionRests on an assumption: Reported incidence and prevalence values from different countries and regions are comparable enough to be combined into a single global staging framework.

May combine two claims.

A systematic review of Latin American studies documented IBD emergence in the twentieth century with rapidly rising incidence during the twenty-first century.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

In 2008, IBD prevalence was 0.51% in Canada and 0.57% in Scotland, close to the 0.53% reported for Olmsted County in 2011.

“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).”

• cites [70] Coward S. Forecasting the Future: A Trek through the Changing Landscape of Inflammatory Bowel Disease. Thesis, Univ. Calgary (2019).Not checked yet

  Not checked in the free run.

• cites [69] Jones, G. R. et al. IBD prevalence in Lothian, Scotland, derived by capture-recapture methodology. Gut 68, 1953–1960 (2019). sourceNot checked yet

  Not checked in the free run.

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

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

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

May combine two claims.

Olmsted County IBD prevalence was 533 per 100,000 in 2011, nearly doubling again over the 20 years after 1991.

“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).”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Since IBD has no cure and mortality is relatively low, patients diagnosed at a young age may live for many years.

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

• cites [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). sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Life expectancy has risen because of public health advances and medical innovation.

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

• cites [74] Appleby, J. How long can we expect to live? BMJ 346, f331 (2013). sourceNot checked yet

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May combine two claims.

Canadian and Scottish population-based studies published in 2019 documented Compounding Prevalence, with prevalence increasing by 3% yearly in Canada and 4% yearly in Scotland during the twenty-first century.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

• cites [69] Jones, G. R. et al. IBD prevalence in Lothian, Scotland, derived by capture-recapture methodology. Gut 68, 1953–1960 (2019). sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

By 2030, the baby boomer generation will be 66-84 years old, and nearly one fifth of Western-world inhabitants will be over 65.

“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.”

• cites [71] Knickman, J. R. & Snell, E. K. The 2030 problem: caring for aging baby boomers. Health Serv. Res. 37, 849–884 (2002). sourceNot checked yet

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May combine two claims.

In São Paulo, Brazil, IBD incidence was 1.0 per 100,000 in 1986-1990, peaked at 13.3 per 100,000 in 2012-2015, and prevalence remained low at 22.6 per 100,000 in 2001-2005.

“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.”

• cites [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). sourceNot checked yet

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• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Forecasts place the 1% prevalence doubling point at 22 years for Canada (2008-2030) and 20 years for Scotland (2008-2028).

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

• cites [69] Jones, G. R. et al. IBD prevalence in Lothian, Scotland, derived by capture-recapture methodology. Gut 68, 1953–1960 (2019). sourceNot checked yet

  Not checked in the free run.

Classified as probably not a substantial claim.

Unmasking of Incidence is a diagnostic bias in which more new IBD cases are diagnosed as the ability to detect IBD improves.

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

May combine two claims.

In the ACCESS inception cohort (2011-2013), IBD incidence was 0.43 per 100,000 in the Philippines versus 2.98 per 100,000 in Hong Kong, and within mainland China varied from 0.54 per 100,000 in Xi'an to 3.64 per 100,000 in Guangzhou.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

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.

“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).”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Inhabitants of these urban environments have been exposed to westernization including diets higher in fat and refined sugars and lifestyle changes such as increased smoking, less breastfeeding, greater antibiotic exposure, and improved hygiene and sanitation.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Lifetime average disease duration cannot be feasibly estimated for IBD, so IBD prevalence cannot be obtained by multiplying incidence by average duration.

“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.”

May combine two claims.

In stage three, incidence greatly outweighs mortality, causing prevalence to rise.

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

May combine two claims.

Historically, IBD typically emerges in a population as ulcerative colitis, followed later by Crohn's disease, and over time Crohn's disease becomes more commonly diagnosed as its incidence approximates or surpasses ulcerative colitis.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

IBD diagnosis is skewed towards ulcerative colitis in lower income regions with limited technology, but as economies improve and health-care infrastructure develops, physicians can more accurately diagnose Crohn's disease.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

In the latter half of the twentieth century, Western-world IBD incidence climbed quickly while prevalence stayed comparatively low, corresponding to stage two.

“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).”

May combine two claims.

Prevalence is expected to rise over the next decade, but as regions enter stage four the prevalence slope will fall and doubling time will lengthen.

“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.”

May combine two claims.

The Western world is in stage three, Compounding Prevalence, and is expected to approach Prevalence Equilibrium within 30 years.

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

May combine two claims.

IBD can and does occur in people from developing countries.

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

• cites [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). sourceNot checked yet

  Not checked in the free run.

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

In South Korea, IBD prevalence was 57.37 per 100,000 in 2009 and had not quite doubled to 95.59 per 100,000 in 2016, suggesting a Prevalence Doubling Period near 10 years.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S4 (based).

Prevalence Equilibrium may reduce prevalence in some jurisdictions, lowering the overall IBD burden.

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

May combine two claims.

If IBD prevalence follows a similar trend in India and China, Asia alone might surpass the Western world in IBD cases before 2050.

“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).”

• cites [57] Kedia, S. & Ahuja, V. Epidemiology of inflammatory bowel disease in India: the great shift east. Inflamm. Intest. Dis. 2, 102–115 (2017). sourceNot checked yet

  Not checked in the free run.

• cites [89] Ye, L., Cao, Q. & Cheng, J. Review of inflammatory bowel disease in China. ScientificWorldJournal 2013, 296470 (2013). sourceNot checked yet

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• cites [1] Kaplan, G. G. The global burden of IBD: from 2015 to 2025. Nat. Rev. Gastroenterol. Hepatol. 12, 720–727 (2015). sourceNot checked yet

  Not checked in the free run.

• AssumptionRests on an assumption: The epidemiological trajectory of newly industrialized nations will mirror that of the Western world.

May combine two claims.

Over the next decade, adult gastroenterologists will face more IBD patients while managing an ageing group with longstanding IBD complications and age-related comorbidities.

“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.”

Classified as probably not a substantial claim.

The second Prevalence Equilibrium indicator will appear in future studies showing prevalence not rising by an expected 50% within 10-12.5 years.

“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.”

May combine two claims.

As IBD patients age, mortality rises; with stable or falling incidence, the steep positive prevalence slope will moderate until prevalence levels off and may decline.

“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.”

May combine two claims.

Japan and South Korea industrialized rapidly after World War II and entered stage two earlier than other Asian countries.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

In Taiwan, IBD prevalence doubled from 4.54 per 100,000 in 2001-2005 to 9.39 per 100,000 in 2006-2010 and nearly doubled again in 2011-2015, suggesting a roughly 5-year Prevalence Doubling Period.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Older IBD patients will form a larger share of adult gastroenterology patients, with EWAR-IBD above 0.5, and octogenarians with IBD will become more common.

“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.”

May combine two claims.

The Western world will move to Prevalence Equilibrium because its IBD population is ageing, as shown by EWAR-IBD.

“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).”

May combine two claims.

Developing countries are in stage one, Emergence, and can expect to enter stage two if their economies grow and societies westernize.

“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.”

• AssumptionRests on an assumption: Developing countries' economies will grow and their societies will westernize.

May combine two claims.

Newly industrialized countries with rapid incidence growth currently have very short Prevalence Doubling Periods, which lengthen as they approach stage three.

“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.”

May combine two claims.

Most newly industrialized countries are in stage two, Acceleration in Incidence, and if they follow Western patterns they will likely enter stage three within three decades.

“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.”

• AssumptionRests on an assumption: The epidemiological trajectory of newly industrialized nations will mirror that of the Western world.

May combine two claims.

Among SECURE-IBD patients over 60, 20% had a severe COVID-19 complication; 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) were linked to poor outcomes.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

All world regions are currently in one of the first three IBD stages and will pass through all four stages over time.

“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).”

• cites [1] Kaplan, G. G. The global burden of IBD: from 2015 to 2025. Nat. Rev. Gastroenterol. Hepatol. 12, 720–727 (2015). sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

A cure for IBD would sharply reduce its incidence.

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

May combine two claims.

Though Prevalence Equilibrium is conjectural, its arrival is indicated by a falling prevalence slope, a longer Prevalence Doubling Period, and a higher EWAR-IBD.

“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).”

May combine two claims.

New IBD diagnoses will keep adding to the prevalent population, sustaining Compounding Prevalence over the next decade, with prevalence forecast at 1% by 2030.

“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).”

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

The ageing IBD population will have shorter life expectancy from age-related comorbidities and a slightly higher death risk than age-matched controls without IBD.

“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.”

• cites [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). sourceNot checked yet

  Not checked in the free run.

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

After decades of accelerated incidence, prevalence will rise rapidly as newly industrialized regions enter Compounding Prevalence, as happened in the Western world around 2000.

“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.”

• AssumptionRests on an assumption: The epidemiological trajectory of newly industrialized nations will mirror that of the Western world.

May combine two claims.

In Japan, IBD prevalence was 24 per 100,000 in 1991, 76 per 100,000 in 2003-2005, and 228.5 per 100,000 in 2014.

“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).”

• cites [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 yet

  Not checked in the free run.

• cites [86] Asakura, K. et al. Prevalence of ulcerative colitis and Crohn’s disease in Japan. J. Gastroenterol. 44, 659–665 (2009). sourceNot checked yet

  Not checked in the free run.

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Newly industrialized countries in Asia and Latin America in stage two currently have rapidly rising incidence and low prevalence.

“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.”

May combine two claims.

South Korean IBD prevalence was 42 per 100,000 in 2005, 63.8 per 100,000 in 2010, and 92.8 per 100,000 in 2015.

“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).”

• cites [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). sourceNot checked yet

  Not checked in the free run.

• cites [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). sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Acceleration in Incidence is driven by Unmasking of Incidence, where economic advance improves IBD detection, and True Rise of Incidence from societal westernization.

“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.”