The burden of inflammatory bowel disease in the United States: a moving target?

Inflammatory bowel disease patients undergoing total hip arthroplasty have higher odds of implant-related complications

PURPOSE

This study evaluates whether IBD patients are at increased risk of implant-related complications after THA.

MATERIALS AND METHODS

A retrospective study from 01 January 2010 to 31 October 31 2020 using an administrative claims database was performed. IBD patients undergoing THA (n = 11,025), without corticosteroid treatment, were propensity score matched to controls in a 1:5 ratio (n = 55,121) based on age, sex, and the Charlson Comorbidity Index (CCI). Outcomes evaluated included periprosthetic fracture, aseptic loosening, prosthetic joint infection, and THA revision within 2 years of index procedure. Chi-square analyses were used to compare the matched cohorts. The association of IBD and implant-related complications was evaluated using logistical regression to calculate odds ratios (ORs), 95% confidence intervals (95% CIs), and p-values. A p-value < 0.001 was used as the significance threshold.

RESULTS

Patients with IBD had a greater incidence and odds of total implant complications (7.03% vs. 3.98%; OR 1.76; p < 0.001) compared with matched controls. IBD patients had significantly higher incidence and odds of developing periprosthetic fracture (0.50% vs. 0.20%; OR 2.46; p < 0.001), THA revisions (2.21% vs. 1.17%; OR 1.91; p < 0.001), aseptic loosening (1.45% vs. 0.84%; OR 1.75; p < 0.001), and prosthetic joint infection (2.87% vs. 1.77%; OR 1.64; p < 0.001).

CONCLUSIONS

Patients with IBD who underwent primary THA had a significantly higher risk of implant-related complications compared to matched controls. Providers should use this study to appropriately assess post-complication risk factors for their patients with IBD.

Metabolomics activity screening of T cell-induced colitis reveals anti-inflammatory metabolites

[Figure: see text].

Coping Among Parents of Teens With Inflammatory Bowel Disease

Parents of teens with inflammatory bowel disease must prepare their children for independent disease self-management. This study characterizes the stressors and coping strategies adopted among parents of teens with inflammatory bowel disease. Teens aged 16-22 years with inflammatory bowel disease who were consecutively seen by a pediatric gastroenterologist prior to transition to adult-centered care and their parents completed sociodemographic data, and two validated questionnaires for coping (Coping Health Inventory for Parents) and stress (Pediatric Inventory for Parents). Sixty-six patient-parent pairs were enrolled in this study-impairment was highest in role function (e.g., trying to attend to the needs of other family members, being unable to go to work, and feeling uncertain about how to maintain consistent discipline). These concerns seemed to be most pronounced among parents of children 18 years and older (χ (df) = 1, p = .04) with Crohn disease (χ (df) = 1, p = .02). The top five listed concerns differed depending on the caregiver's gender. Parents of teens with inflammatory bowel disease are concerned about parenting role function. Parents of teens 18 years and older with Crohn disease reported the highest stress. Caregiver gender differences were noted.

De-escalation of IBD Therapy: When, Who, and How?

When patients with inflammatory bowel disease reach clinical remission with biologic therapy, a question that often comes up is, “when can I stop my biologic medication?” This is a question fraught with challenges for both physicians and patients. For physicians, there are valid concerns that stepping down from a successful therapy will lead to relapse and disease exacerbation, and that stepping down could lead to anti-biologic antibodies. For patients, the question is often driven by concerns about long-term side effects and costs of biologics. This review provides an overview of the rationale for, and risks of, withdrawal of IBD therapy. Selected studies have shown how to identify subsets of patients in whom de-escalation can be performed with low risk of relapse. Practical guidance on when and how to de-escalate IBD therapy is provided.

Identifying Patients With Inflammatory Bowel Diseases in an Administrative Health Claims Database: Do Algorithms Generate Similar Findings?

Application of selective algorithms to administrative health claims databases allows detection of specific patients and disease or treatment outcomes. This study identified and applied different algorithms to a single data set to compare the numbers of patients with different inflammatory bowel disease classifications identified by each algorithm. A literature review was performed to identify algorithms developed to define inflammatory bowel disease patients, including ulcerative colitis, Crohn's disease, and inflammatory bowel disease unspecified in routinely collected administrative claims databases. Based on the study population, validation methods, and results, selected algorithms were applied to the Optum Clinformatics® Data Mart database from June 2000 to March 2017. The patient cohorts identified by each algorithm were compared. Three different algorithms were identified from literature review and selected for comparison (A, B, and C). Each identified different numbers of patients with any form of inflammatory bowel disease (323 833; 246 953, and 171 537 patients, respectively). The proportions of patients with ulcerative colitis, Crohn's disease, and inflammatory bowel disease unspecified were 32.0% to 47.5%, 38.6% to 43.8%, and 8.7% to 26.6% of the total population with inflammatory bowel disease, respectively, depending on the algorithm applied. Only 5.1% of patients with inflammatory bowel disease unspecified were identified by all 3 algorithms. Algorithm C identified the smallest cohort for each disease category except inflammatory bowel disease unspecified. This study is the first to compare numbers of inflammatory bowel disease patients identified by different algorithms from a single database. The differences between results highlight the need for validation of algorithms to accurately identify inflammatory bowel disease patients.

Predicting Hospitalization and Outpatient Corticosteroid Use in Inflammatory Bowel Disease Patients Using Machine Learning

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic disease characterized by unpredictable episodes of flares and periods of remission. Tools that accurately predict disease course would substantially aid therapeutic decision-making. This study aims to construct a model that accurately predicts the combined end point of outpatient corticosteroid use and hospitalizations as a surrogate for IBD flare.

METHODS

Predictors evaluated included age, sex, race, use of corticosteroid-sparing immunosuppressive medications (immunomodulators and/or anti-TNF), longitudinal laboratory data, and number of previous IBD-related hospitalizations and outpatient corticosteroid prescriptions. We constructed models using logistic regression and machine learning methods (random forest [RF]) to predict the combined end point of hospitalization and/or corticosteroid use for IBD within 6 months.

RESULTS

We identified 20,368 Veterans Health Administration patients with the first (index) IBD diagnosis between 2002 and 2009. Area under the receiver operating characteristic curve (AuROC) for the baseline logistic regression model was 0.68 (95% confidence interval [CI], 0.67-0.68). AuROC for the RF longitudinal model was 0.85 (95% CI, 0.84-0.85). AuROC for the RF longitudinal model using previous hospitalization or steroid use was 0.87 (95% CI, 0.87-0.88). The 5 leading independent risk factors for future hospitalization or steroid use were age, mean serum albumin, immunosuppressive medication use, and mean and highest platelet counts. Previous hospitalization and corticosteroid use were highly predictive when included in specified models.

CONCLUSIONS

A novel machine learning model substantially improved our ability to predict IBD-related hospitalization and outpatient steroid use. This model could be used at point of care to distinguish patients at high and low risk for disease flare, allowing individualized therapeutic management.

Considerations in Imaging Among Emergency Department Patients With Inflammatory Bowel Disease

Patients with inflammatory bowel disease who experience abdominal pain and gastrointestinal symptoms often seek care in the emergency department (ED). These patients commonly undergo abdominopelvic computed tomography (CT) as part of their evaluation, and the rate of imaging appears to be increasing without a corresponding increase in identification of clinically actionable findings or effect on disposition. Studies demonstrate that the yield of CT tends to be fairly high. Yet, because inflammatory bowel disease is often diagnosed at an early age, these patients are repeatedly imaged during their lifetime, a subset of whom accumulate high levels of ionizing radiation exposure, increasing their risk of cancer. This compounds an already increased risk of cancer in these patients because of inflammatory bowel disease alone. Lack of intimate knowledge of a patient's disease phenotype and disease progression contributes to uncertainty in distinguishing between an inflammatory exacerbation; a complication such as obstruction, abscess, perforation, fistula, or stricture; and a noninflammatory-bowel-disease-related condition. This uncertainty can lead to overuse of imaging with CT. Limited availability of and lack of awareness of alternate imaging modalities and strategies may prevent providers from pursuing strategies that avoid ionizing radiation. In this article, we review options for imaging inflammatory bowel disease patients in the ED and attempts undertaken to risk stratify these patients, and we discuss ways in which details of a patient's disease might guide imaging decisionmaking.

TNFRSF1B Is Associated with ANCA in IBD

The genetic basis of antineutrophil cytoplasmic antibody, an important biomarker of inflammatory bowel disease (IBD), has never been thoroughly examined on a genome-wide scale. In this study, we performed a 2-stage genome-wide association study (GWAS) on antineutrophil cytoplasmic antibody in IBD cases. In the 2959 IBD cases in the discovery stage, we observed an association between a variant in the gene TNFRSF1B with antineutrophil cytoplasmic antibody level (rs5745994, minor allele frequency = 0.028, beta = 18.12, 95% CI, 11.82-24.22, P = 1.89 × 10). This association was replicated in an independent cohort of 419 IBD cases (beta = 16.91, 95% CI, 6.13-27.69, P = 2.38 × 10). With a Q-value of 0.036, we performed a fixed-effect meta-analysis for the association of rs5745994 in both cohorts and observed a stronger association signal (beta = 17.81, 95% CI, 12.36-23.25, P = 8.97 × 10). TNFRSF1B gene codes for tumor necrosis factor (TNF) receptor 2 (TNFR2), thereby we examined the reported TNFRSF1B variant with serum TNFR2 level. We observed a negative association with serum TNFR2 level being 8.23 EU/mL in carriers and 9.12 EU/mL in noncarriers (P = 0.033). This finding indicates the functional role of identified TNFRSF1B variant in IBD serology and may be reflective of the underlying biological mechanisms that determine clinical expression and/or response to certain therapies.

Vitamin D receptor pathway is required for probiotic protection in colitis

Low expression of vitamin D receptor (VDR) and dysfunction of vitamin D/VDR signaling are reported in patients with inflammatory bowel disease (IBD); therefore, restoration of VDR function to control inflammation in IBD is desirable. Probiotics have been used in the treatment of IBD. However, the role of probiotics in the modulation of VDR signaling to effectively reduce inflammation is unknown. We identified a novel role of probiotics in activating VDR activity, thus inhibiting inflammation, using cell models and VDR knockout mice. We found that the probiotics Lactobacillus rhamnosus strain GG (LGG) and Lactobacillus plantarum (LP) increased VDR protein expression in both mouse and human intestinal epithelial cells. Using the VDR luciferase reporter vector, we detected increased transcriptional activity of VDR after probiotic treatment. Probiotics increased the expression of the VDR target genes, such as antimicrobial peptide cathelicidin, at the transcriptional level. Furthermore, the role of probiotics in regulating VDR signaling was tested in vivo using a Salmonella-colitis model in VDR knockout mice. Probiotic treatment conferred physiological and histologic protection from Salmonella-induced colitis in VDR(+/+) mice, whereas probiotics had no effects in the VDR(-/-) mice. Probiotic treatment also enhanced numbers of Paneth cells, which secrete AMPs for host defense. These data indicate that the VDR pathway is required for probiotic protection in colitis. Understanding how probiotics enhance VDR signaling and inhibit inflammation will allow probiotics to be used effectively, resulting in innovative approaches to the prevention and treatment of chronic inflammation.

Anti-inflammatory activity on mice of extract of Ganoderma lucidum grown on rice via modulation of MAPK and NF-κB pathways

Ganoderma lucidum is a popular medicinal mushroom with anti-inflammatory potential. In the present study, the aim was to determine the anti-inflammatory effect and mode of action of G. lucidum grown on germinated brown rice (GLBR) in a mouse model of colitis. It was shown that GLBR suppressed the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in lipopolysaccharide (LPS)-stimulated macrophages and decreased the expression of COX-2, TNF-α, iNOS, IL-1β, IL-6, and IL-10 mRNAs. GLBR also inhibited activation of p38, ERK, JNK, MAPKs, and nuclear factor kappa-B (NF-κB). In a mouse model of colitis, colonic mucosal injury was evaluated using macroscopic, biochemical, and histopathological testing. Disease activity index (DAI), macroscopic score, and histological score significantly decreased upon GLBR treatment. Moreover, immunofluorescence studies indicated that DSS activates nuclear translocation of NF-κB in colon tissue, which is attenuated by GLBR extract. These findings suggest that GLBR is protective against colitis via inhibition of MAPK phosphorylation and NF-κB activation.

Decreasing incidence of inflammatory bowel disease in eastern Canada: a population database study

Background

Nova Scotia has one of the highest incidences of inflammatory bowel disease (IBD) in the world. We wished to determine trends of IBD over time.

Methods

All Provincial residents have government provided health insurance and all interactions with the hospital, and physician billing systems, are captured on an administrative database. We used a validated measure to define incident cases of Crohn’s (CD), ulcerative colitis (UC) and undifferentiated IBD (IBDU). Incidence rates of these diseases for the years 1996–2009 were calculated.

Results

Over the study period, 7,153 new cases of IBD were observed of which 3,046 cases were categorized as CD (42.6%), 2,960 as UC (41.4%) and 1,147 as IBDU (16.0%). Annual age standardized incidence rates were very high but have declined for CD from 27.4 to 17.7/100,000 population and for UC from 21.4 to 16.7/100,000. The decline was seen in all age groups and both genders. The decrease was not explained by a small increase in IBDU.

Conclusion

The incidence of CD and UC are decreasing in Nova Scotia. If replicated elsewhere this indicates a reversal after a long period of increasing occurrence of IBD. This has implications for both epidemiology and health planning.

Real-world assessment of therapy changes, suboptimal treatment and associated costs in patients with ulcerative colitis or Crohn's disease

BACKGROUND

Treatments for Crohn's disease (CD) and ulcerative colitis (UC) are not uniformly effective, thus necessitating dose changes, switching, and augmentation and carry adverse event risk, often requiring discontinuation, which reduces treatment benefits.

AIM

To assess continuity of and changes to initial CD and UC treatments, as well as costs associated with specific parameters defining suboptimal therapy.

METHODS

Commercial US insurance claims (2006-2010) were retrospectively analysed. CD and UC patients receiving monotherapy with 5-aminosalicylates (5-ASAs), corticosteroids (CS), immunomodulators (IM) or biologics were included. Continuity of and changes to initial (index) therapy and associated costs (2011 US$) were assessed over 12 months following therapy initiation. Suboptimal therapy included discontinuation or switch (except for CS), dose escalation, augmentation, inadequate loading (biologics only), prolonged CS use (>3 months), surgery or hospitalisation.

RESULTS

The study included 13,005 CD and 19,878 UC patients. Augmentation was a common index therapy change (~20% of 5-ASA initiators, ~40% of CS initiators, ≥40% of IM initiators and 26-55% of biologic initiators) in both CD and UC patients. Approximately 50% of CD and UC 5-ASA initiators discontinued/interrupted treatment. Approximately 80% of CD and UC patients had ≥1 suboptimal therapy marker. Mean all-cause total costs per CD patient were significantly higher in those with vs. without suboptimal therapy ($18,736 vs. $10,878; P < 0.001); in UC, the disparity was smaller ($12,679 vs. $9653; P < 0.001).

CONCLUSIONS

Frequent dose and treatment changes were observed in all classes of initial UC and CD treatments. The economic impact of suboptimal therapy among UC and CD patients is substantial.

Racial/Ethnic and regional differences in the prevalence of inflammatory bowel disease in the United States

BACKGROUND

The magnitude of racial/ethnic and regional differences in the prevalence of inflammatory bowel disease (IBD) in the United States remains largely unknown.

AIMS

To estimate differences in the prevalence of IBD by race/ethnicity and region.

METHODS

The Medical Expenditure Panel Survey, a nationally representative survey of US households and medical conditions, was used. A multivariate logistic model was used in statistical analysis.

RESULTS

Among 202,468 individuals surveyed during 1996-2007, 316 were diagnosed with IBD (26 Blacks, 21 Hispanics, and 5 Asians). The prevalence of IBD was higher in Whites [Crohn's disease: 154; ulcerative colitis (UC): 89] than Blacks (Crohn's disease: 68; UC: 25), Hispanics (Crohn's disease: 15; UC: 35), and Asians (Crohn's: 45; UC: 40) (all p < 0.05, except for UC in Asians). The differences in Crohn's disease between Whites and minorities and the difference in UC between Whites and Blacks remained significant in multivariate analysis. In multivariate analysis, there was no regional difference in the prevalence of Crohn's disease, but the prevalence of UC was higher in the Northeast than the South (p < 0.05).

CONCLUSIONS

There were significant racial/ethnic differences in the prevalence of IBD in the USA. The underlying etiology of these differences warrants additional research.

Chronic intestinal inflammation: inflammatory bowel disease and colitis-associated colon cancer

The inflammatory bowel diseases (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC), are chronic inflammatory disorders of the intestine. The prevalence in the United States is greater than 200 cases per 100,000, with the total number of IBD patients between 1 and 1.5 million. CD may affect all parts of the gastrointestinal tract, from mouth to anus, but most commonly involves the distal part of the small intestine or ileum, and colon. UC results in colonic inflammation that can affect the rectum only, or can progress proximally to involve part of or the entire colon. Clinical symptoms include diarrhea, abdominal pain, gastrointestinal bleeding, and weight loss. A serious long-term complication of chronic inflammation is the development of colorectal cancer. A genetic basis for IBD had long been recognized based on the increased familial risk. However, significant discordance for CD in twins, and a much less robust phenotypic concordance for UC, suggested additional factors play a role in disease pathogenesis, including environmental factors. In the past several years, progress in understanding the molecular basis of IBD has accelerated, beginning with the generation of animal models of colitis and progressing to the identification of specific genetic markers from candidate gene, gene linkage, and genome-wide association analyses. Genetic studies have also resulted in the recognition of the importance of environmental factors, particularly the crucial role of the gut microbiota in CD and UC. Altered immune responses to the normal intestinal flora are key factors in IBD pathogenesis. In this research topic, the genetic basis of IBD, the genetic and cellular alterations associated with colitis-associated colon cancer, and the emerging role of the intestinal microbiota and other environmental factors will be reviewed.

Imaging inflammation in mouse colon using a rapid stage-scanning confocal fluorescence microscope

Large area confocal microscopy may provide fast, high-resolution image acquisition for evaluation of tissue in pre-clinical studies with reduced tissue processing in comparison to histology. We present a rapid beam and stage-scanning confocal fluorescence microscope to image cellular and tissue features along the length of the entire excised mouse colon. The beam is scanned at 8,333 lines/sec by a polygon scanning mirror while the specimen is scanned in the orthogonal axis by a motorized translation stage with a maximum speed of 7 mm/sec. A single 1 × 60 mm(2) field of view image spanning the length of the mouse colon is acquired in 10 s. Z-projection images generated from axial image stacks allow high resolution imaging of the surface of non-flat specimens. In contrast to the uniform size, shape, and distribution of colon crypts in confocal images of normal colon, confocal images of chronic bowel inflammation exhibit heterogeneous tissue structure with localized severe crypt distortion.

Risk of diagnosed fractures in children with inflammatory bowel diseases

BACKGROUND

Decreased bone mass is common in children with inflammatory bowel disease (IBD); however, fracture risk is unknown. We sought to evaluate fracture risk in children with IBD as compared to unaffected controls and determine whether this risk is affected by geographical region (a proxy for sun/vitamin D exposure) and oral steroid use.

METHODS

We identified cases of Crohn's disease (CD) and ulcerative colitis (UC), less than 20 years of age, using administrative data from 87 health plans. Each case was matched to three controls on the basis of age, gender, and geographical region. We identified fractures in cases and controls using ICD-9 diagnosis codes and measured oral steroid exposure using NDC codes.

RESULTS

The study included 733 children with CD, 488 with UC, and 3287 controls (mean age 15 years). IBD was not associated with a higher risk of fracture at any site (CD odds ratio [OR] 0.8, 95% confidence interval [CI] 0.6-1.1; UC OR 1.4, 95% CI 1.0-2.1) or at multiple sites (CD OR 0.8, 95% CI 0.4-1.7; UC OR 0.4, 95% CI 0.1-1.4). Among IBD patients we did not identify any significant differences in the fracture rate between those residing in the Northeast/Midwest versus the South (OR 1.3, 95% CI 0.8-2.2). Steroid exposure was not associated with the occurrence of fractures (P = 0.6).

CONCLUSIONS

Children with IBD are no more likely to have experienced a diagnosed fracture than age-, sex-, and gender-matched controls.

Inflammatory bowel disease aggregation in Utah kindreds

BACKGROUND

The observed heritability of inflammatory bowel disease (IBD) is incompletely explained by known genetic risk factors. Kindred-specific genetic variants that cause IBD may be a source of "missing heritability." Given that they have been previously difficult to identify, we sought to identify high-risk IBD kindreds.

METHODS

We used a large population-based database--the Utah Population Database (UPDB)--which contains genealogical and healthcare data to characterize the risk of Crohn's disease (CD), ulcerative colitis (UC), and IBD in kindreds. We identified CD and UC cases using ICD-9 codes. We calculated the adjusted relative risk to relatives of affected individuals. We calculated the familial standardized incidence ratio (FSIR) to quantify the kindred-specific disease risk.

RESULTS

In all, 3601 CD cases and 3976 UC cases met inclusion criteria. A total of 655 CD kindreds and 615 UC kindreds had a statistical excess of disease. Risk of disease varied among kindreds, with some kindreds demonstrating ≈ 20-fold elevated risk. For CD, UC, and IBD, relative risks were significantly elevated for first- and second-degree relatives and first cousins. The adjusted population attributable risks for familial CD, UC, and IBD were 0.20 (95% confidence interval [CI]: 0.17-0.23); 0.17 (0.14-0.21); and 0.19 (0.17-0.22), respectively.

CONCLUSIONS

We identified multiple kindreds with a statistical excess of CD, UC, and IBD, and validated the UPDB as a resource for family studies in IBD. Given the need for novel genetic mapping strategies to explain the apparent missing heritability in IBD, further studies of these high-risk kindreds is justified.

The contributions of child behavioral functioning and parent distress to family functioning in pediatric inflammatory bowel disease

The objective of this study was to examine the relative contributions of both parental and adolescent functioning to family functioning in adolescent patients with inflammatory bowel disease (IBD) and their families. Participants were 45 adolescents (27 male, 18 female) 13-17 years old (M = 15.41 years, SD = 1.32) with IBD and their parents. Families completed measures of patient behavioral functioning and depression, parent distress and family functioning. Disease severity assessments were completed via data provided by patients' gastroenterologists. Results indicated that parent-reported patient behavioral problems accounted for a significant 26% of variance in family functioning. Post-hoc analysis revealed that externalizing behavior problems accounted for the majority of this variance compared to internalizing behavior problems. These results suggest that externalizing problems may have a more significant impact on these families than previous research indicates. Moreover, externalizing behaviors may significantly impact family adaptation and should be taken into consideration during routine clinical care. Further research is needed to replicate and expand upon these findings.

Utilization of healthcare resources by U.S. children and adults with inflammatory bowel disease

BACKGROUND

The inflammatory bowel diseases (IBDs) Crohn's disease (CD) and ulcerative colitis (UC) affect over 1 million people in the United States, yet little is known about healthcare utilization by affected individuals. The objectives were to describe the healthcare utilization associated with IBD in an insured U.S. population and to determine how sociodemographic factors impact healthcare utilization in this population.

METHODS

Using an administrative database comprised of 87 health plans, we ascertained cases of CD and UC using an administrative definition. We identified inpatient, office-based, emergency (ED), and endoscopy services occurring between 2003-2004 in IBD patients and matched controls. For each case, excess utilization was determined by subtracting the mean number of control visits from the number of case visits. Multivariate logistic and linear regressions were used to identify the sociodemographic factors associated with excess utilization.

RESULTS

We identified 9056 CD patients and 10,364 UC patients. The mean number of annual excess hospitalizations, ED visits, and office visits per 100 patients for CD were 21.7, 20.1, and 493, respectively. These values for UC were 13.3, 10.3, and 364, respectively. In general, utilization was higher in CD compared with UC, and in younger patients compared with older patients. Utilization also varied by gender, geographical region, and insurance type (Medicaid versus commercial).

CONCLUSIONS

In the U.S., patients with IBD consume substantial healthcare resources. Resource utilization varies by patient age and disease type, and to a lesser extent, gender, geographical region, and insurance type. These findings may be used to inform health policy.

Trends in surgery for Crohn's disease in the era of infliximab

OBJECTIVE

To examine the use of surgical procedures for Crohn's disease since the introduction of infliximab.

SUMMARY BACKGROUND DATA

Prior studies have shown that the overall rate of surgery for Crohn's disease has not changed significantly since the introduction of infliximab, an immunomodulator considered particularly effective in treating Crohn's fistulas. How infliximab has affected individual rates of specific types of procedures, particularly surgery for intestinal fistulas, is unknown.

METHODS

We used the Nationwide Inpatient Sample to identify all hospital admissions for Crohn's disease for each year from 1993 through 2004. Cases of Crohn's disease and relevant surgical interventions were identified using International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes. Using US Census data to establish population denominators, trends in population-based rates of use of these procedures were examined over time. Trends were tested for significance with Spearman rank correlation tests.

RESULTS

From 1993 to 2004, there was no statistically significant change in population-based rates of small bowel and right colon resection, while rates of left colon resection, other colon resection, and rectal resection declined moderately. However, rates of surgical repair of fistulas of the small intestine, the most commonly performed fistula operation, increased by 60%, from 1.5 per 1,000,000 in 1993 to 2.4 per 1,000,000 in 2004 (P = 0.04).

CONCLUSIONS

During the period of adoption of infliximab as a novel treatment for Crohn's disease, overall rates of bowel resections have either remained relatively stable or decreased moderately, while rates of small bowel fistula repair have increased significantly. These findings call into question the effectiveness of infliximab in preventing the need for surgery for Crohn's disease at the population level.

Stem cells as potential therapeutic targets for inflammatory bowel disease

The incidence and prevalence of Crohn's disease and ulcerative colitis, the two major forms of inflammatory bowel disease (IBD), are rising. According to some estimates >1 million new cases of IBD arise in the United States annually. The conventional therapies available for IBD range from anti-inflammatory drugs to immunosuppressive agents, but these therapies generally fail to achieve satisfactory results due to their side effects. Interest in a new therapeutic option, that is, biological therapy, has gained much momentum recently due to its focus on different stages of the inflammatory process. Stem cell (SC) research has become a new direction for IBD therapy due to our recent understanding of cell populations involved in the pathogenic process. To this end, hematopoietic and mesenchymal stem cells are receiving more attention from IBD investigators. The intestinal environment, with its crypts and niches, supports incoming embryonic and hematopoietic stem cells and allows them to engraft and differentiate. The above findings suggest that, in the future, SC-based therapy will be a promising alternative to conventional therapy for IBD. In this review, we discuss SCs as potential therapeutic targets for future treatment of IBD.

Inflammatory bowel disease, gut bacteria and probiotic therapy

Crohn's disease (CD) and ulcerative colitis (UC) are the two major forms of inflammatory bowel disease (IBD) and both diseases lead to high morbidity and health care costs. Complex interactions between the immune system, enteric commensal bacteria and host genotype are thought to underlie the development of IBD although the precise aetiology of this group of diseases is still unknown. The understanding of the composition and complexity of the normal gut microbiota has been greatly aided by the use of molecular methods and is likely to be further increased with the advent of metagenomics and metatranscriptomics approaches, which will allow an increasingly more holistic assessment of the microbiome with respect to both diversity and function of the commensal gut microbiota. Studies thus far have shown that the intestinal microbiota drives the development of the gut immune system and can induce immune homeostasis as well as contribute to the development of IBD. Probiotics which deliver some of the beneficial immunomodulatory effects of the commensal gut microbiota and induce immune homeostasis have been proposed as a suitable treatment for mild to moderate IBD. This review provides an overview over the current understanding of the commensal gut microbiota, its interactions with the mucosal immune system and its capacity to induce both gut homeostasis as well as dysregulation of the immune system. Bacterial-host events, including interactions with pattern recognition receptors (PRRs) expressed on epithelial cells and dendritic cells (DCs) and the resultant impact on immune responses at mucosal surfaces will be discussed.

Inflammatory bowel disease in the setting of autoimmune pancreatitis

BACKGROUND

Despite scattered case reports, the prevalence of inflammatory bowel disease (IBD) in patients with autoimmune pancreatitis (AIP) is unknown. We sought to better characterize the putative association between the conditions.

METHODS

Medical records of 71 patients meeting accepted criteria for AIP were reviewed to identify those with endoscopic and histological evidence of IBD. Colon samples in patients with both AIP and IBD were immunostained to identify IgG4-positive cells.

RESULTS

Four patients with AIP (5.6%) had a diagnosis of IBD: 3 had ulcerative colitis (UC) and 1 had Crohn's disease (CD). The diagnosis of IBD preceded or was simultaneous to that of AIP. Two AIP-UC patients treated for AIP with prednisone had a recurrence of AIP, and 1 required 6-mercaptopurine for long-term corticosteroid-sparing treatment. Two AIP-IBD patients underwent Whipple resections, and 1 had recurrent AIP. All 3 patients with UC presented with pancolitis, and 2 required colectomy. Colon samples from 1 patient with UC and 1 patient with CD were available for review. Increased numbers of IgG4-positive cells (10 per high-power field) were noted on the colon sample from the patient with UC.

CONCLUSIONS

Almost 6% of patients with proven AIP had a diagnosis of IBD, compared to a prevalence of approximately 0.4%-0.5% in the general population, potentially implying a 12-15-fold increase in risk. Patients with both AIP and IBD may have increased extent and severity of IBD. The finding of IgG4-positive cells on colon biopsy suggests that IBD may represent an extrapancreatic manifestation of AIP.

The evolving epidemiology of inflammatory bowel disease

PURPOSE OF REVIEW

Epidemiologic studies in inflammatory bowel disease (IBD) include assessments of disease burden and evolving patterns of disease presentation. Although it is hoped that sound epidemiologic studies provide aetiological clues, traditional risk factor-based epidemiology has provided limited insights into either Crohn's disease or ulcerative colitis etiopathogenesis. In this update, we will summarize how the changing epidemiology of IBD associated with modernization can be reconciled with current concepts of disease mechanisms and will discuss studies of clinically significant comorbidity in IBD.

RECENT FINDINGS

The increased frequency of IBD, which has been consistently observed as society becomes developed or modernized, may be linked with changes in the gastrointestinal microbiota which, in turn, may affect the development of the immune system and influence the risk of inflammatory diseases. Although extra-intestinal disease associations have long been recognized to be linked to IBD, there is a disturbing increase in comorbidity with Clostridium difficile-associated disease, arterial and venous thromboembolism and abnormalities of cervical cytology. These have important implications in an era of increased use of immunomodulatory drugs.

SUMMARY

Advances in understanding the basic biology of IBD with rapidly emerging therapeutic strategies have prompted a shift in traditional epidemiologic approaches away from risk factor anthologies toward rapprochement with disease mechanisms and pursuit of changing patterns of comorbidity of clinical relevance.

Direct health care costs of Crohn's disease and ulcerative colitis in US children and adults

BACKGROUND & AIMS

Data regarding the health care costs of inflammatory bowel disease (IBD) in the United States are limited. The objectives of this study were to estimate the direct costs of Crohn's disease (CD) and ulcerative colitis (UC) in the United States, describe the distribution of costs among inpatient, outpatient, and pharmaceutical services, and identify sociodemographic factors influencing these costs.

METHODS

We extracted medical and pharmacy claims from an administrative database containing insurance claims from 87 health plans in 33 states, occurring between 2003 and 2004. We identified cases of CD and UC using an administrative definition. For each case, we selected up to 3 non-IBD controls. Claims were classified as inpatient, outpatient, or pharmaceutical according to Current Procedural Terminology codes or National Drug Codes. Costs were based on the paid amount of each claim. IBD-attributable costs were estimated by subtracting costs for non-IBD patients from those for patients with IBD. Logistic regression was used to identify the sociodemographic factors affecting these costs.

RESULTS

We identified 9056 patients with CD and 10,364 patients with UC. Mean annual costs for CD and UC were $8265 and $5066, respectively. For CD, 31% of costs were attributable to hospitalization, 33% to outpatient care, and 35% to pharmaceutical claims. The corresponding distribution for UC was 38%, 35%, and 27%, respectively. Costs were significantly higher for children younger than 20 years compared with adults, but this did not vary substantially by sex or region.

CONCLUSIONS

This study demonstrates a substantial economic burden of IBD and can be used to inform health policy.

Balsalazide disodium for the treatment of ulcerative colitis

5-aminosalicylates remain the first-line treatment for patients with ulcerative colitis. A number of formulations are available for the treatment of active ulcerative colitis, including encapsulated mesalazine and mesalazine in combination with other molecules. Balsalazide is an aminosalicylate prodrug that releases mesalazine in the colon, thus exerting its multiple anti-inflammatory effects in areas of colitis. This review will examine the pharmacological and therapeutic features of balsalazide as an anti-inflammatory agent in ulcerative colitis. The introduction of novel aminosalicylate formulations and an appreciation of their molecular mode of action, has renewed interest in these agents in both maintenance of disease remission and cancer prevention.