Gastroenterology Research and Practice

Review Article

The Changing Phenotype of Inflammatory Bowel Disease

Table 1

The changing phenotype of patients with IBD [3].


Feature	Comment	Reference

Increased BMI	(i) Prevalence of obese and overweight patients in a Scottish IBD population was 18% and 38%, respectively.	[19]
	(ii) 17% of patients with CD in an Irish cohort were obese compared to 12% of controls.	[16]
	(iii) A third of patients with IBD attending metropolitan health services in Texas were obese.	[20]
	(iv) Increased weight of patients with CD enrolling in clinical trials (1991–2008).	[21]
	(v) 23% of paediatric patients with IBD in United States found to be overweight or obese.	[30]

Decreased rate of surgery	(i) Cumulative probability of first major surgery at 9 years decreased from 50% (1979–86) to 23% (2003–11) in patients with CD and 14% to 9% in patients with UC.	[69]
	(ii) Decreased risk of surgery in patients diagnosed with CD after 1996, associated with increased specialist care.	[70]
	(iii) Reduced surgical rates in patients with CD associated with increased and earlier immunomodulator use.	[71, 72]

Reduced proportion of patients with short bowel syndrome	(i) Largely due to improvements and specialization of surgical care. (ii) Partially due to improvements in medical treatments.	Almost a universal observation

Increasing prevalence of elderly onset IBD	(i) Increased proportion of colonic disease and inflammatory behavior, in elderly patients with CD.	[38, 46]
Increasing prevalence of elderly onset IBD	(ii) Progression of disease behavior less than in younger patients. Milder disease course than younger cohorts.	[38]

Reduced risk of colorectal cancer (CRC) in recent decades	(i) Meta-analysis of population studies found that CRC elevated in patients with IBD, but not as high as previously reported.	[73]
Reduced risk of colorectal cancer (CRC) in recent decades	(ii) Nationwide study in Denmark found that risk of CRC in patients with UC no longer exceeds that of general population.	[74]