Epidemiology and Natural History of Inflammatory Bowel Diseases

https://www.thelancet.com/pdfs/journals/lancet/PIIS0140673612600269.pdf

Crohn's disease

Irritable bowel syndrome

Ulcerative colitis and Crohn’s disease are the principal forms of inflammatory bowel disease. Both represent chronic inflammation of the gastrointestinal tract, which displays heterogeneity in inflammatory and symptomatic burden between patients and within individuals over time. Optimal management relies on understanding and tailoring evidence-based interventions by clinicians in partnership with patients. This guideline for management of inflammatory bowel disease in adults over 16 years of age was developed by Stakeholders representing UK physicians (British Society of Gastroenterology), surgeons (Association of Coloproctology of Great Britain and Ireland), specialist nurses (Royal College of Nursing), paediatricians (British Society of Paediatric Gastroenterology, Hepatology and Nutrition), dietitians (British Dietetic Association), radiologists (British Society of Gastrointestinal and Abdominal Radiology), general practitioners (Primary Care Society for Gastroenterology) and patients (Crohn’s and Colitis UK). A systematic review of 88 247 publications and a Delphi consensus process involving 81 multidisciplinary clinicians and patients was undertaken to develop 168 evidence- and expert opinion-based recommendations for pharmacological, non-pharmacological and surgical interventions, as well as optimal service delivery in the management of both ulcerative colitis and Crohn’s disease. Comprehensive up-to-date guidance is provided regarding indications for, initiation and monitoring of immunosuppressive therapies, nutrition interventions, pre-, peri- and postoperative management, as well as structure and function of the multidisciplinary team and integration between primary and secondary care. Twenty research priorities to inform future clinical management are presented, alongside objective measurement of priority importance, determined by 2379 electronic survey responses from individuals living with ulcerative colitis and Crohn’s disease, including patients, their families and friends.

https://gut.bmj.com/content/gutjnl/68/Suppl_3/s1.full.pdf

British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults

Recent years have seen a rapid rise in the medical and recreational use of cannabis: a broad term that can be used to describe the various products and chemical compounds (e.g., marijuana, cannabinoids) derived from different species of the cannabis plant. Despite increased cannabis use and a changing state-level policy landscape, conclusive evidence regarding the shortand long-term health effects—both harms and benefits—of cannabis use remains elusive.

/pdf/the-health-effects-of-cannabis-and-cannabinoids-the-current-10v11e4i7b.pdf

The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research

Irritable bowel syndrome (IBS) is a functional condition of the bowel that is diagnosed using clinical criteria. This paper discusses the nature of the diagnostic process for IBS and how this impacts epidemiological measurements. Depending on the diagnostic criteria employed, IBS affects around 11% of the population globally. Around 30% of people who experience the symptoms of IBS will consult physicians for their IBS symptoms. These people do not have significantly different abdominal symptoms to those who do not consult, but they do have greater levels of anxiety and lower quality of life. Internationally, there is a female predominance in the prevalence of IBS. There is 25% less IBS diagnosed in those over 50 years and there is no association with socioeconomic status. IBS aggregates within families and the genetic and sociological factors potentially underlying this are reviewed. Patients diagnosed with IBS are highly likely to have other functional disease and have more surgery than the general population. There is no evidence that IBS is associated with an increased mortality risk. The epidemiological evidence surrounding these aspects of the natural history is discussed.

/pdf/the-epidemiology-of-irritable-bowel-syndrome-3qjlsexp4p.pdf

The epidemiology of irritable bowel syndrome.

Summary
Background Crohn's disease is associated with small bowel cancer whilst risk of colorectal cancer is less clear

Aim  To ascertain the combined estimates of relative risk of these cancers in Crohn's disease

Methods  MEDLINE was searched to identify relevant papers Exploding references identified additional publications When two papers reviewed the same cohort, the later study was used

Results  Meta-analysis showed overall colorectal cancer relative risk in Crohn's disease as 25 (13–47), 45 (13–149) for patients with colonic disease and 11 (08–15) in ileal disease Meta-regression showed reduction in relative risk over the past 30 years Subgroup analysis showed Scandinavia had significantly lower colorectal cancer relative risk than the UK and North America Cumulative risk analysis showed 10 years following diagnosis of Crohn's disease relative risk of colorectal cancer is 29% (15%–53%) Meta-analysis showed small bowel cancer relative risk in Crohn's disease is 332 (159–609) Small bowel cancer relative risk has not significantly reduced over the last 30 years

Conclusion  Relative risk of colorectal and small bowel cancers are significantly raised in Crohn's disease Cumulative risk of colorectal cancer of 29% at 10 years suggests a potential benefit from routine screening However, the value of screening requires rigorous appraisal

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2036.2006.02854.x

Meta-analysis: colorectal and small bowel cancer risk in patients with Crohn's disease.

Background: Irritable bowel syndrome (IBS) is a chronic functional disorder of the gastrointestinal system affecting a large number of people worldwide. Whilst it has no attributable mortality, it has substantial impact on patients' quality of life (QoL) and is associated with considerable healthcare resource use. 

Aim: To review the economic impact of IBS, firstly on the individual, secondly on healthcare systems internationally and thirdly to society. 

Methods: Appropriate databases were searched for relevant papers using the terms: Irritable Bowel Syndrome; IBS; irritable colon; functional bowel/colonic disease; economics; health care/service costs; health expenditure/resources; health care/service utilisation; productivity. 

Results: Irritable bowel syndrome impacts most substantially on patients' work and social life. Reduction in QoL is such that on average patients would sacrifice between 10 and 15 years of their remaining life expectancy for an immediate cure. Between 15% and 43% of patients pay for remedies. No studies quantify loss of earnings related to IBS. Direct care costs are substantial; 48% of patients incur some costs in any year with annual international estimates per patient of: USA $742–$7547, UK £90–£316, France €567–€862, Canada $259, Germany €791, Norway NOK 2098 (€262) and Iran $92. Minimising extensive diagnostic investigations could generate savings and has been shown as not detrimental to patients. Cost to industry internationally through absenteeism and presenteeism related to IBS is estimated between £400 and £900 per patient annually. 

Conclusions: costs to patients, healthcare systems and society. Considerable benefit could be obtained from effective interventions.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/apt.12938

Review article: the economic impact of the irritable bowel syndrome.

Summary Aim: To perform a meta-analysis is of published literature reporting standardized mortality ratios (SMR) for Crohn's patients from 1970 to date. Methods: Medline search identified relevant papers. Exploding references identified additional papers. When two papers reviewed mortality of one patient group at different times, the later publication was used. Results: Of 13 papers identified, three studies reported SMR below 1.0, two others had confidence intervals including 1.0. All other studies reported mortality higher than the general population. Meta-analysis using a random effects model shows the pooled estimate for SMR in Crohn's disease is 1.52 (95% CI: 1.32 to 1.74 [ P < 0.0001]). Meta-regression shows the SMR for these patients has decreased slightly over the past 30 years, but this decrease is not statistically significant ( P = 0.08). Conclusion: Assessing evidence from original studies and conducting a meta-analysis shows age-adjusted mortality risk from Crohn's disease is over 50% greater than the general population. Whilst mortality has improved since the condition was first recognized, further evaluation of the patients studied in the cohorts included here is necessary to assess more recent changes in clinical practice.

C. Canavan

Papers

The epidemiology of irritable bowel syndrome.

Meta-analysis: colorectal and small bowel cancer risk in patients with Crohn's disease.

Review article: the economic impact of the irritable bowel syndrome.

Meta-analysis: mortality in Crohn's disease.

Meta-analysis: colorectal and small bowel cancer risk in patients with Crohn's disease.