Prior Appendectomy Is Associated With a Milder Clinical Course in Crohn's Disease: A Nationwide Population-based Cohort Study

BACKGROUND

Appendectomy may affect the clinical course of Crohn's disease (CD), but rigorous evidence is sparse and contradicting. The aim of this study was to examine the association between appendectomy and the clinical course of CD.

METHODS

All patients diagnosed with CD in Denmark in the period from 1977 to 2017 were identified from the Danish National Patient Registry. Patients with appendectomy were matched with up to 10 comparators with CD and no appendectomy; and rates of CD-related hospital admissions were compared between CD patients with and without appendectomy using incidence rate ratios (IRRs). We used stratified Cox regression analysis to calculate adjusted hazard ratios (aHRs) of initiating treatment with biologics or undergoing intestinal resections.

RESULTS

In all, 21 189 CD patients (1936 with appendectomy and 19 253 without) were identified and followed for a median of 13.6 years. Crohn's disease patients who had undergone appendectomy experienced a lower rate of CD-related hospital admissions (appendectomy before CD: IRR = 0.83; 95% confidence interval [CI], 0.81-0.85; appendectomy after CD: IRR = 0.85; 95% CI, 0.81-0.88) compared with CD patients without appendectomy. For patients with appendectomy before CD diagnosis, the rate of initiating biologics was lower compared with CD patients with no appendectomy (aHR1-<5 years = 0.61; 95% CI, 0.46-0.81; aHR5-<10 years 0.47; 95% CI, 0.33-0.66; aHR10-20 years = 0.61; 95% CI, 0.47-0.79), as was the risk of undergoing colorectal resections (aHR1-<5 years = 0.94; 95% CI, 0.77-1.15; aHR5-<10 years 0.63; 95% CI, 0.47-0.85; aHR10-20 years = 0.75; 95% CI, 0.54-1.04). Rates of small bowel resections were comparable for CD patients with or without appendectomy prior to CD. Appendectomy performed after CD did not influence the rate of initiating treatment with biologics or undergoing intestinal resections.

CONCLUSION

The clinical course of CD is milder for those who have previously undergone appendectomy.

Short-term outcomes following total colectomy for inflammatory bowel disease in Denmark after implementation of laparoscopy: a nationwide population-based study

AIM

A laparoscopic approach to total colectomy (TC) for inflammatory bowel disease (IBD) is being increasingly used, but data on its comparative benefits over open TC are conflicting. The aim of this study was to examine 90-day outcomes following laparoscopic and open TC for IBD in a nationwide cohort after the introduction of laparoscopy.

METHOD

IBD patients undergoing TC in Denmark from 2005 to 2017 were identified from the Danish National Patient Registry. We used Kaplan-Meier methodology to estimate mortality and Cox regression analysis to estimate adjusted mortality rate ratios (aMRRs) and adjusted hazard ratios (aHRs) of reoperation, readmission and intensive care unit (ICU) transfer, comparing patients undergoing laparoscopic versus open TC.

RESULTS

We identified 1095 patients undergoing laparoscopic TC and 1523 patients undergoing open TC. Following emergency TC, 90-day mortality was 2.8% (1.6%-4.9%) after laparoscopic TC and 9.1% (7.0%-11.8%) after open TC. Ninety-day mortality was 0.9% (0.3%-2.5%) after laparoscopic TC and 2.6% (1.5%-4.3%) after open elective TC. The aMRRs associated with laparoscopic TC were 0.45 (95% CI 0.25-0.80) in emergency cases and 0.29 (95% CI 0.10-0.86) in elective cases. Risks of readmission were comparable following laparoscopic versus open TC, both in emergency [aHR = 0.93 (95% CI 0.76-1.15)] and elective [aHR = 0.83 (95% CI 0.68-1.02)] cases, while risks of ICU transfer and reoperation were lower following laparoscopic TC, both in emergency cases [aHR = 0.53 (95% CI 0.35-0.82) and aHR = 0.26 (95% CI 0.15-0.47)] and elective [aHR = 0.58 (95% CI 0.35-0.95) and aHR = 0.37 (95% CI 0.21-0.66)] cases.

CONCLUSION

The introduction of laparoscopic TC for IBD in Denmark was not associated with increased mortality or morbidity. In fact, laparoscopic TC for IBD may be associated with lower short-term mortality and morbidity compared with open TC.

Appendectomy and Risk of Advanced Colorectal Neoplasia in Inflammatory Bowel Disease: A Nationwide Population-based Cohort Study

BACKGROUND

The aim of this study was to examine the association between appendectomy and advanced colorectal neoplasia (aCRN) in patients with inflammatory bowel disease (IBD).

METHODS

Inflammatory bowel disease patients diagnosed in Denmark in the period 1977 to 2017 were identified from the Danish National Patient Registry. Inflammatory bowel disease patients who underwent appendectomy were matched with up to 10 IBD patients without appendectomy and followed until aCRN, death, or emigration. Absolute risks of aCRN were calculated, treating death and bowel resections as competing risks. Stratified Cox regression was used to calculate adjusted hazard ratios (aHRs) of aCRN, comparing IBD patients with appendectomy to IBD patients without appendectomy.

RESULTS

We identified 3789 IBD patients with appendectomy and 37 676 IBD patients without appendectomy. A total of 573 patients (1.4%) developed aCRN, with an absolute risk of aCRN at 20 years of 4.9% (95% confidence interval [CI], 2.9%-7.7%) for ulcerative colitis (UC) patients with appendectomy after UC diagnosis compared with 2.8% (95% CI, 2.3%-3.3%) for UC patients without appendectomy. Appendectomy after UC was associated with an increased rate of aCRN 5 to 10 years (aHR, 2.5; 95% CI, 1.1-5.5) and 10 to 20 years after appendectomy (aHR, 2.3; 95% CI, 1.0-5.5). Appendectomy prior to UC diagnosis was not associated with an increased rate of aCRN, and Crohn's disease was not associated with the rate of aCRN, regardless of timing or histological diagnosis of the appendix specimen.

CONCLUSIONS

Although appendectomy may have a positive effect on the clinical course of UC, our study suggests that this may come at the expense of a higher risk of aCRN.

A population-based nationwide study on total colectomy for ulcerative colitis and risk of ten prevalent inflammatory or autoimmune diseases

BACKGROUND

There is growing evidence to support a role of the gut microbiome in the development of chronic inflammatory and autoimmune disease (IAD). We used total colectomy (TC) for ulcerative colitis (UC) as a model for a significant disruption in gut microbiome to explore an association with subsequent risk of IAD.

METHODS

We identified all patients with UC and no diagnosis of IAD prior to their UC diagnosis in Denmark from 1988 to 2015. Patients were followed from the date of UC to a diagnosis of IAD, death or end of follow-up, whichever occurred first. We used Cox regression to estimate hazard ratios (HRs) of IAD associated with TC, adjusting for age, sex, Charlson Comorbidity Index, and calendar year of UC diagnosis.

RESULTS

30,507 patients with UC (3,155 with TC and 27,352 without) were identified from the Danish National Patient Registry. During 43,266 person-years of follow-up, 2733 patients were diagnosed with an IAD. The risk of any IAD was higher for patients with TC compared to patients without (adjusted HR [aHR] 1.39 (95% CI: 1.24-1.57)). When the analyses were adjusted for exposure to antibiotics, immunomodulatory medicine and biologics (covering 2005-2018), the risk of IAD was still higher for patients with total colectomy (aHR = 1.41 (95% CI: 1.09;1.83)). Disease-specific analyses were weakened by a low number of outcomes.

CONCLUSIONS

The risk of IAD was higher for patients who underwent TC for UC compared to patients who did not.KEY MESSAGESWhat is already known?o The gut microbiome plays an important role in host immune homeostasis, and changes in gut bacterial diversity and composition may change the individual's risk of inflammatory and autoimmune disease (IAD).What is new here?o Patients with ulcerative colitis who undergo total colectomy have a higher risk of being diagnosed with IAD, compared to patients with ulcerative colitis who do not undergo total colectomy.How can this study help patient care?o Future research can help uncover the mechanisms responsible for the higher risk of certain IADs after total colectomy. If the microbiome plays a role, modifying the gut microbiome could prove a viable therapeutic strategy to reduce the risk of developing IADs.

Early-Life Exposure to Antibiotics and Risk for Crohn's Disease: A Nationwide Danish Birth Cohort Study

BACKGROUND

Early-life antibiotic use can alter the intestinal flora and modify the risk of developing Crohn disease (CD), but rigorous epidemiological evidence is limited, with inconsistent results.

METHODS

We identified all children born in Denmark from 1995 to 2009 and followed them from birth until death, emigration, a diagnosis of CD, or January 1, 2013. Using Cox regression, we assessed the association between antibiotic exposure in the first year of life and subsequent risk for CD, adjusting for sex, degree of urbanization, birth order, birth year, route of delivery, gestational age, smoking during pregnancy, intake of nonsteroidal anti-inflammatory drugs in the first year of life, and family history of CD.

RESULTS

During a median 9.5 years (9.3 million total person-years), CD was diagnosed in 208 of 979,039 children. Antibiotic use in the first year of life was associated with a higher risk of CD (adjusted hazard ratio, 1.4; 95% confidence interval [CI], 1.1-1.8), with the highest risk with ≥6 courses of antibiotics (adjusted hazard ratio, 4.1; 95% CI, 2.0-8.5). A family history of CD did not modify these risk associations. The cumulative risk of CD at the 11th birthday for children exposed to antibiotics in their first year of life was 0.16‰ (95% CI, 0.11‰-0.22‰) compared to 0.11‰ (95% CI, 0.08‰-0.15‰) for children unexposed to antibiotics in their first year of life.

CONCLUSIONS

Antibiotic use in the first year of life is associated with a modestly increased risk for CD, although the absolute risk is very low.

Extracolonic Cancer Risk After Total Colectomy for Inflammatory Bowel Disease: A Population-based Cohort Study

BACKGROUND

Patients with inflammatory bowel disease are at increased risk of extracolonic cancers. Little is known regarding this risk following total colectomy [TC].

METHODS

Patients who underwent TC for inflammatory bowel disease in Denmark during 1977-2013 were identified from the Danish National Patient Registry. Incidence rates of extracolonic cancers were determined through record linkage to the Danish Cancer Registry and compared with expected incidence rates in the general population. Standardized incidence ratios [SIRs] were calculated as the observed vs expected cancer incidence.

RESULTS

In total, 4430 patients (3441 with ulcerative colitis [UC]; 989 with Crohn's disease [CD]) were followed for 54,183 person-years after TC. Following their surgery, 372 patients were diagnosed with extracolonic cancer compared to 331 expected [SIR = 1.1 (95% confidence interval {CI}: 1.0-1.2)]. The risk of extracolonic cancer overall was increased among patients with CD and TC (SIR = 1.5 [95% CI: 1.2-1.8]), but not among patients with UC and TC (SIR = 1.0 [95% CI: 0.9-1.2]). Patients with UC and TC had a higher risk of intestinal extracolonic cancer (SIR = 2.0 [95% CI: 1.4-2.7]). Patients with CD and TC had a higher risk of smoking-related cancers (SIR = 1.9 [95% CI: 1.2-2.9]), intestinal extracolonic cancer (SIR = 3.1 [95% CI: 1.6-5.5]) and immune-mediated cancers (SIR = 1.5 [95% CI: 1.0-2.1]).

CONCLUSION

Patients with CD and TC had a higher risk of extracolonic cancer overall compared to the general population, while patients with UC and TC did not. Site-specific cancer risk varied according to inflammatory bowel disease type.

Long-term Risk of Cancer Following Ileal Pouch-anal Anastomosis for Ulcerative Colitis

BACKGROUND

The overall risk of cancer following ileal pouch-anal anastomosis [IPAA] is unknown, and pouch cancer surveillance is controversial. We evaluated long-term risk of cancer in a national cohort of patients with ulcerative colitis and IPAA, with emphasis on pouch cancer.

METHODS

Data on incident cancers were extracted from the national Danish Cancer Registry. Incidence rates for all site-specific cancers were compared between patients with IPAA and a gender- and age-matched comparison cohort from the background population to obtain incidence rate ratios [IRRs].

RESULTS

A total of 1723 patients with IPAA, operated for ulcerative colitis in the period 1980-2010, were matched to 8615 individuals from the background population. During a median follow-up of 12.9 years (interquartile range [IQR] 7.7-19.6 years), two pouch cancers [0.12%] were found after 16 and 27 years, respectively. In the population comparison cohort, 38 intestinal cancers [0.45%] were found, of which 35 were colorectal. The risk of hepatobiliary cancer was higher for patients with IPAA {IRR = 13.0 (95% confidence interval [CI]: 3.1-76.1)}, and half of the affected patients had coexisting primary sclerosing cholangitis. The risk of cancer overall following IPAA was identical to that of the comparison cohort: IRR = 1.05 [0.84-1.31].

CONCLUSIONS

Pouch cancer following IPAA is very rare, questioning the need for general, rather than selective, surveillance. The overall cancer risk is comparable to that of the background population, and the increased risk of hepatobiliary cancer is likely an effect of coexisting liver disease and not causally related to IPAA.

Pouch failures following ileal pouch-anal anastomosis for ulcerative colitis

AIM

Ileal pouch-anal anastomosis is a procedure offered to patients with ulcerative colitis who opt for restoration of bowel continuity. The aim of this study was to determine the risk of pouch failure and ascertain the risk factors associated with failure.

METHOD

The study included 1991 patients with ulcerative colitis who underwent ileal pouch-anal anastomosis in Denmark in the period 1980-2013. Pouch failure was defined as excision of the pouch or presence of an unreversed stoma within 1 year after its creation. We used Cox proportional hazards regression to explore the association between pouch failure and age, gender, synchronous colectomy, primary faecal diversion, annual hospital volume (very low, 1-5 cases per year; low, 6-10; intermediate 11-20; high > 20), calendar year, laparoscopy and primary sclerosing cholangitis.

RESULTS

Over a median 11.4 years, 295 failures occurred, corresponding to 5-, 10- and 20-year cumulative risks of 9.1%, 12.1% and 18.2%, respectively. The risk of failure was higher for women [adjusted hazard ratio (aHR) 1.39, 95% CI 1.10-1.75]. Primary non-diversion (aHR 1.63, 95% CI 1.11-2.41) and a low hospital volume (aHR, very low volume vs high volume 2.30, 95% CI 1.26-4.20) were also associated with a higher risk of failure. The risk of failure was not associated with calendar year, primary sclerosing cholangitis, synchronous colectomy or laparoscopy.

CONCLUSION

In a cohort of patients from Denmark (where pouch surgery is centralized) with ulcerative colitis and ileal pouch-anal anastomosis, women had a higher risk of pouch failure. Of modifiable factors, low hospital volume and non-diversion were associated with a higher risk of pouch failure.

Increased Risk of Gallstone Disease Following Colectomy for Ulcerative Colitis

OBJECTIVES

Biochemical studies suggest that patients who have had a colectomy or restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) are at an increased risk of developing gallstone disease, but epidemiological studies are lacking. We evaluated the risk of gallstone disease following colectomy and IPAA.

METHODS

Individuals who had a colectomy were identified from a national cohort of patients with ulcerative colitis (UC), and controls without colectomy were sampled from within the same cohort, matching on gender, calendar year, and year of birth. We used Cox regression to examine the effect of colectomy on the hazard rates of gallstone disease and cholecystectomy, adjusting for alcoholism, stroke, chronic obstructive pulmonary disease, cancer, cardiac disease, diabetes mellitus, hypothyroidism, hyperlipidemia, cirrhosis, obesity, renal failure, and transient ischemic attacks. The effect of an IPAA was determined for patients who had colectomy by including the procedure as a time-dependent variable.

RESULTS

We identified 4548 patients and matched these to 44 372 controls without colectomy. During a median follow-up of 11.9 years, 1963 patients were hospitalized for gallstone disease. Patients who had a colectomy were at an increased risk (adjusted hazard ratio (HR)=1.63 (1.39-1.91)), and sensitivity analyses of the risk of undergoing cholecystectomy revealed a similar association (adjusted HR=1.55 (1.22-1.98)). An IPAA did not affect the risk of developing gallstones among patients who had a colectomy (adjusted HR=1.03 (0.77-1.37)).

CONCLUSION

The risk of gallstone disease increases following colectomy for UC.

Magnetic endoscopic imaging as an adjuvant to elective colonoscopy: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND STUDY AIMS

The use of magnetic endoscopic imaging (MEI) to visualize scope configuration in three dimensions is thought to increase procedural efficiency and diminish discomfort associated with colonoscopy. The aim of this systematic review and meta-analysis was to evaluate the performance of MEI in colonoscopy.

METHODS

The electronic databases Medline, EMBASE, and the Cochrane Library of Randomized Trials were searched. Methodological quality was assessed using the Jadad score. Odds ratios (OR) or risk differences for dichotomous variables and mean differences for continuous outcomes were calculated with 95 % confidence intervals (CIs).

RESULTS

A total of 13 randomized studies met eligibility criteria and were included in qualitative and quantitative synthesis. MEI was associated with a significantly lower risk of failed cecal intubation (risk difference 4 %, 95 %CI 0 % - 7 %; P = 0.03), lower cecal intubation time (mean difference 0.58 minutes, 95 %CI 0.28 - 0.88; P < 0.001), and lower pain scores as estimated by visual analog scales (mean difference 0.45 cm, 95 %CI 0.03 - 0.86; P = 0.03) compared with conventional colonoscopy. On subgroup stratification of outcome according to endoscopist experience, failure rates were unaffected, but experienced colonoscopists reduced intubation times with MEI (mean difference 0.78 minutes, 95 %CI 0.12 - 1.43; P = 0.02). Sensitivity analyses of high-quality studies (Jadad score ≥ 3) showed no significant difference in failure rate (risk difference 4 %, 95 %CI 0 % - 8 %; P = 0.07) or intubation time (mean difference 0.56 minutes, 95 %CI - 0.15 to 1.28; P = 0.12).

CONCLUSION

Adjuvant MEI is associated with a lower failure risk and shorter time to cecal intubation during elective colonoscopy compared with conventional colonoscopy.