Geographic distributions of microscopic colitis and inflammatory bowel disease in the United States

Similar geographic distribution of mortality from multiple sclerosis, Hodgkin lymphoma, and inflammatory bowel disease in the United States

BACKGROUND

Previous epidemiologic studies have suggested a linkage between the occurrence of multiple sclerosis (MS), Hodgkin lymphoma (HL), Crohn's disease (CD), and ulcerative colitis (UC). It was hypothesized that the 4 diagnoses would be characterized by similar geographic distributions within the United States.

AIMS

To compare the US geographic distributions of these 4 diagnoses in a cross-sectional study.

METHODS

Using the US vital statistics, state-specific death rates and age-specific proportional mortality ratios (PMR) were calculated for each diagnosis. Similarities in the geographic distributions of the 4 diagnoses were tested by linear and Poisson regression analyses. The PMR values from different states were correlated among pairs of consecutive age-groups.

RESULTS

The 6 linear correlation coefficients (r) among the geographic distributions of the 4 diseases were as follows: HL vs. MS (r = 0.28), HL vs. CD (r = 0.74), HL vs. UC (r = 0.64); MS vs. CD (r = 0.18), MS vs. UC (r = 0.66); CD vs. UC (r = 0.58). Using Poisson regression, the geographic distributions of MS, HL, CD, and UC were all found to be significantly correlated with each other. In MS, significant correlations between the PMR values of each two consecutive age-groups started with the age-group 25-44 years. In HL, such significant correlations started at age 10-14, in CD at age 20-24, and in UC at age 20-24 years.

CONCLUSIONS

Within the United States, mortality from MS, HL, CD, and UC are characterized by similar geographic distributions. The environmental influences responsible for these resembling geographic distributions start exerting their influence during early lifetime.

Similar geographic distributions of death rates from inflammatory bowel disease and Hodgkin lymphoma or multiple sclerosis

BACKGROUND

A previous comparative analysis of the time trends of Hodgkin lymphoma (HL), multiple sclerosis (MS), Crohn's disease (CD), and ulcerative colitis (UC) suggested that the occurrence of all four diseases was precipitated by exposure to similar environmental risk factors during early lifetime. In the present cross-sectional study, it was hypothesized that besides their resembling temporal variations the four diseases would also show similar geographic distributions.

METHODS

Using the vital statistics of 21 countries from 1951 to 2020, overall and age-specific death rates from the four diseases were calculated for each individual country. The death rates of different countries were compared using linear regression analysis.

RESULTS

The data revealed strikingly similar geographic distributions of all four diseases. Their occurrence was common in Europe and relatively uncommon in countries outside Europe. Further stratification by consecutive age groups showed that for each disease analyzed separately, there were significant correlations amongst each two sequential age groups. In HL and UC, the inter-age correlations started at age 5 years or less. In MS and CD, the inter-age correlations only started at age 15 years.

CONCLUSIONS

The similarities in the geographic distributions of death rates from HL, MS, CD, and UC suggest that these four diseases share a set of one or more common environmental risk factors. The data also support the contention that the exposure to such shared risk factors starts during an early period of lifetime.

High levels of fecal calprotectin and C-reactive protein in patients with colitis

Inflammatory bowel disease (IBD) with a poor prognosis may be due to persistent colitis. According to the latest guidelines, monitoring has become a part of the treatment process for colitis. Adequate monitoring of the patient's condition is necessary to determine the course of the disease to prevent the worsening of the condition and suppress the subclinical inflammatory process. This analytical study with a cross-sectional design was conducted to evaluate the activity of colitis using the results of C-reactive protein (CRP) and fecal calprotectin (FC) assays. FC levels were analyzed by ELISA, while CRP levels were analyzed using Siemens Flex particle-enhanced turbidimetric immunoassay. In 30 subjects with endoscopy and biopsy of colitis, 16 men and 14 women had a median age of 52.5 (18-70) years. The median FC value increased by 67 (7.3-722 g/g) and was positive (≥50 g/g) in 20 subjects (66.7%), and the mean CRP value was 13.64 mg/L, positive (10-15 mg/L) in 13 subjects (43.33%), and negative (<10 mg/L) in 17 subjects (56.67%). This study demonstrated that FC had a significant relationship with CRP (r=0.57; p<0.001) in patients with colitis. Assessing the levels of FC and CRP among patients with colitis can be useful to assess the worsening of symptoms early and reduce mortality and morbidity.

Similar Time Trends of Hodgkin Lymphoma, Multiple Sclerosis, and Inflammatory Bowel Disease

BACKGROUND

The Epstein-Barr virus (EBV) plays a role in the causation of Hodgkin lymphoma (HL) and multiple sclerosis (MS). A previous study showed that the time trends of mortality from Crohn's disease (CD) and MS shared striking similarities. It was hypothesized that such similarities would also involve the time trends of ulcerative colitis and HL.

AIMS

To compare the time trends of CD and UC with those of HL and MS in 6 different countries.

METHODS

Using the vital statistics of England, Canada, Netherlands, Scotland, Switzerland, and United States from 1951 to 2020, the time trends of mortality from these 4 diseases were compared. The time-dependent changes of death rates were subjected to a birth-cohort analysis.

RESULTS

Similar trends were observed in all 6 countries. UC mortality rose among generations born during the nineteenth century and decreased among all generations born subsequently during the twentieth century. CD mortality was similarly characterized by a birth-cohort pattern with a rise and fall that were shifted by 20-30 years towards more recent generations when compared to UC. The birth-cohort pattern of UC was matched by a similar pattern of HL, whereas the birth-cohort pattern of CD was matched by a similar pattern of MS.

CONCLUSIONS

The similarities in the ubiquitous birth-cohort patterns of UC, CD, HL, and MS suggest that these 4 diseases share a common environmental risk factor. Such risk factor may be linked to EBV or its acquisition during an early period of a patient's lifetime.

The Meaning of Incidental Goblet Cells at the Gastroesophageal Junction

BACKGROUND AND AIMS

The causes for the occurrence of goblet cells at the gastroesophageal junction (GEJ-GC) are unknown. The aim of our study was to compare the concurrent histologic changes of the stomach in (1) patients with GEJ-GC, but without Barrett's esophagus (BE) to those in (2) patients with BE and in (3) controls without GEJ-GC or BE.

METHODS

We used an electronic database of histopathologic records from 1.3 million individual patients, who underwent esophago-gastro-duodenoscopy (EGD) in 2009-2018. We compared the prevalence of Helicobacter pylori-positive gastritis (HpG), gastric intestinal metaplasia (G-IM), chronic inactive gastritis (CIG), and reactive gastropathy (RG) among the 3 patient groups, using odds ratios and their 95% confidence intervals.

RESULTS

Of all EGD patients, 4.0% harbored BE and 2.4% GEJ-GC. The average age of patients with GEJ-GC (60 ± 14) was significantly younger than the age of patients with BE (63 ± 12) and significantly older than the age of controls (55 ± 17). Female subjects were more common among GEJ-GC (54%) than BE (37%), but less common than among controls (63%). The 3 gastric histopathology changes associated with H. pylori were significantly more common in GEJ-GC than BE (for HpG 2.42, 2.29-2.56; for G-IM 1.82, 1.73-1.92; for CIG 1.31, 1.22-1.41). The corresponding differences between GEJ-GC and controls were less striking (for HpG 0.97, 0.93-1.01; for G-IM 1.15, 1.11-1.19; for CIG 0.90, 0.85-0.95). RG was slightly less common in GEJ-GC than BE (0.89, 0.86-0.92) and controls (0.94, 0.91-0.96).

CONCLUSIONS

With respect to its demographic and histopathologic features, GEJ-GC likely represents gastric intestinal metaplasia as opposed to BE and should prompt gastric intestinal metaplasia screening and management.

Efficacy of stem cells therapy for Crohn's fistula: a meta-analysis and systematic review

BACKGROUND

Fistulas have puzzled us all the time and stem cell therapy for it is still in its infancy. We conducted a meta-analysis and systematic review to evaluate the efficacy of stem cells and its potential mechanisms in the management of Crohn's fistula.

METHODS

Electronic databases were searched comprehensively for studies reporting the efficacy and safety of stem cells in patients with any form of Crohn's fistula. A random-effects model was used, and all outcomes were calculated by SPSS 24.0.

RESULTS

Twenty-nine articles with 1252 patients were included. It showed that stem cell group had a higher rate of fistula healing compared to placebo group in patients of Crohn's fistula (61.75% vs 40.46%, OR 2.21, 95% CI 1.19 to 4.11, P < 0.05). 3 × 10⁷ cells/mL stem cell (SC) group had an advantage in fistula healing rate with 71.0% compared to other doses group of stem cells (RR 1.3, 95% CI 0.76 to 2.22). And the healing rates of patients with perianal and transsphincteric fistulas (77.95%, 76.41%) were higher than those with rectovaginal fistulas. It was an amazing phenomenon that CDAI and PDAI scores occurred an obviously transient rise with the use of stem cells after 1 month (both of P < 0.05), while they returned to the baseline level by giving stem cells 3 months later. Furthermore, the incidence rate of treatment-related adverse events in the stem cell group was significantly lower than in the placebo group (RR 0.58, 95% CI 0.30 to 1.14).

CONCLUSIONS

Our study has highlighted that stem cells was a promising method in the treatment of Crohn's fistula based on its higher efficacy and lower incidence of adverse events, especially ADSCs and Cx601. While it also needs more clinical and pre-clinical studies to strengthen evidences in the future.

The role of vitamin D in inflammatory bowel disease: a guide for clinical practice

INTRODUCTION

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract that carries significant morbidity and mortality. Given the need to identify modifiable risk factors to prevent IBD development and to mitigate disease severity, vitamin D has become a major candidate of interest.

AREAS COVERED

In this review, we discuss the regulatory role played by vitamin D in intestinal immune homeostasis, updates in the recent literature exploring its role in de novo IBD pathogenesis and established IBD activity. We also discuss societal recommendations on its therapeutic role in maintaining bone health and future directions for studying its role in regulating disease activity.

EXPERT OPINION

In contrast to findings from earlier studies suggesting a causal role in IBD, recent findings indicate that vitamin D deficiency may be a sequela rather than a cause of IBD. Additionally, clinical trials exploring vitamin D therapy in reducing disease activity remain inconclusive thus far, with the current evidence best supporting a therapeutic role of vitamin D in bone health. Future studies are needed to clarify the role of vitamin D in IBD development and disease activity and to determine its therapeutic potential for IBD disease activity.

The Role of Vitamin D in Inflammatory Bowel Disease - Assessing Therapeutic and Preventive Potential of Supplementation and Food Fortification

Inflammatory bowel diseases are a group of chronic inflammatory conditions that affect gastrointestinal tract due to inapt and continuous immune activation in response to a myriad of predisposing factors (most notably genetics, environmental impact and gut microbiota composition). It has been shown that vitamin D status can also play a role in the disease pathogenesis, as its deficiency is commonly observed in two major forms of inflammatory bowel diseases - Crohn's disease and ulcerative colitis. Mounting evidence supports the concept of intricate relationship between gut dysbiosis and vitamin D metabolism, while suboptimal levels of this vitamin have been linked to increased clinical disease relapse rates, inadequate response to drugs, as well as decreased quality of life in patients with Crohn's disease and ulcerative colitis. Consequently, the pertinent question is whether increased vitamin D supplementation and (on a population level) food fortification may bring significant benefit to the affected individuals. In this short review we discuss the synthesis, functions, status and food sources of vitamin D, appraise biotechnological facets of vitamin D status analysis and food fortification, and concentrate on novel developments in the field that describe its influence on intestinal microbiota and inflammatory bowel disease.

Health-Risk Behaviors and Chronic Conditions Among Adults with Inflammatory Bowel Disease - United States, 2015 and 2016

Inflammatory bowel disease (IBD), which includes Crohn's disease and ulcerative colitis, involves chronic inflammation of the gastrointestinal tract. In 2015, an estimated 3.1 million adults in the United States had ever received a diagnosis of IBD (1). Nationally representative samples of adults with IBD have been unavailable or too small to assess relationships between IBD and other chronic conditions and health-risk behaviors (2). To assess the prevalence of health-risk behaviors and chronic conditions among adults with and without IBD, CDC aggregated survey data from the 2015 and 2016 National Health Interview Survey (NHIS). An estimated 3.1 million (unadjusted lifetime prevalence = 1.3%) U.S. adults had ever received a diagnosis of IBD. Adults with IBD had a significantly lower prevalence of having never smoked cigarettes than did adults without the disease (55.9% versus 63.5%). Adults with IBD had significantly higher prevalences than did those without the disease in the following categories: having smoked and quit (26.0% versus 21.0%; having met neither aerobic nor muscle-strengthening activity guidelines (50.4% versus 45.2%); reporting <7 hours of sleep, on average, during a 24-hour period (38.2% versus 32.2%); and having serious psychological distress (7.4% versus 3.4%). In addition, nearly all of the chronic conditions evaluated were more common among adults with IBD than among adults without IBD. Understanding the health-risk behaviors and prevalence of certain chronic conditions among adults with IBD could inform clinical practice and lead to better disease management.

Solar radiation is inversely associated with inflammatory bowel disease admissions

OBJECTIVE

To explore the associations between latitude and solar radiation with inflammatory bowel disease admission rates in Chile, the country with the largest variation in solar radiation in the world.

PATIENTS AND METHODS

This is an ecological study, which included data on all hospital-admitted population for inflammatory bowel disease between 2001 and 2012, according to different latitudes and solar radiation exposures in Chile. The data were acquired from the national hospital discharge database from the Department of Health Statistics and Information of the Chilean Ministry of Health.

RESULTS

Between 2001 and 2012 there were 12,869 admissions due to inflammatory bowel disease (69% ulcerative colitis, 31% Crohn's disease). Median age was 36 years (IQR: 25-51); 57% were female. The national inflammatory bowel disease admission rate was 6.52 (95% CI: 6.40-6.63) per 100,000 inhabitants with increasing rates over the 12-year period. In terms of latitude, the highest admission rates for pediatric ulcerative colitis and Crohn's disease, as well as adult ulcerative colitis, were observed in the southernmost region with lowest annual solar radiation. Linear regression analysis showed that regional solar radiation was inversely associated with inflammatory bowel disease admissions in Chile (β: -.44, p = .03).

CONCLUSIONS

Regional solar radiation was inversely associated with inflammatory bowel disease admission rates in Chile; inflammatory bowel disease admissions were highest in the southernmost region with lowest solar radiation. Our results support the potential role of vitamin D deficiency on inflammatory bowel disease flares.

Differences in the socio-economic distribution of inflammatory bowel disease and microscopic colitis

AIM

Inflammatory bowel disease (IBD) and microscopic colitis are characterized by different geographical distributions across the USA. In this cross-sectional study we utilized demographic and socio-economic information associated with individual ZIP codes to further delineate the epidemiological characteristics of the two diseases.

METHOD

A total of 813 057 patients who underwent colonoscopy between 2008 and 2014 were extracted from an electronic database of histopathology reports. The prevalence of patients with IBD or microscopic colitis was expressed as percentage of the population associated with specific demographic (age, sex, ethnicity) and socio-economic characteristics (population size, housing value, annual income, tertiary education).

RESULTS

Both diseases were more common among subjects from ZIP codes with predominantly White residents and less common among subjects from ZIP codes with predominantly non-White residents such as Black, Hispanic and Asian. These ethnic variations were more pronounced in microscopic colitis than IBD. Markers of affluence, such as average residential house value and annual income, were positively associated with IBD and negatively with microscopic colitis. The prevalence of both diseases was positively correlated with tertiary education.

CONCLUSION

The occurrence of both IBD and microscopic colitis is influenced by environmental risk factors. The differences in the demographic, ethnic and socio-economic distributions of the two diseases suggest that different sets of risk factors affect the two diseases and that their aetiology is unrelated.

Vitamin D and the Pathogenesis of Inflammatory Bowel Disease

Vitamin D has traditionally been known for its role in bone metabolism, but emerging evidence has suggested a broader role for vitamin D in immune regulation. Vitamin D deficiency has been associated with the pathogenesis of diverse autoimmune disorders and has similarly been implicated as a contributor to inflammatory bowel disease. In this review, we discuss animal, in vitro, genetic, and epidemiologic studies that have linked vitamin D deficiency with inflammatory bowel disease pathogenesis or severity. Nonetheless, we present the caveat in interpreting these studies in the context of reverse causation: Does vitamin D deficiency lead to gastrointestinal disease, or does gastrointestinal disease (with related changes in dietary choices, intestinal absorption, nutritional status, lifestyle) lead to vitamin D deficiency?

The Role of T-Cell Subsets in Chronic Inflammation in Celiac Disease and Inflammatory Bowel Disease Patients: More Common Mechanisms or More Differences?

Background

Chronic intestinal inflammation due to noninfectious causes represents a growing health issue all over the world. Celiac disease as well as inflammatory bowel diseases (IBD) like Crohn's disease and ulcerative and microscopic colitis involve uncontrolled T-cell activation and T-cell-mediated damage as common denominators. Therefore, diagnosis and treatment decisions clearly benefit from the knowledge of the intricacies of the systemic and the local T-cell activity.

Summary

Depending on the cytokine milieu, CD4⁺ T cells can differentiate into proinflammatory T helper 1 (Th1), anti-inflammatory Th2, antimicrobial Th17, pleiotropic Th9, tissue-instructing Th22 cells, and in the regulatory compartment forkhead box protein 3⁺ Treg, suppressive Tr1 or Th3 cells. Additionally, follicular Th cells provide B-cell help in antibody class switching; cytotoxic CD8⁺ T cells target virus-infected or tumor cells. This review discusses our current knowledge on the contribution of defined T-cell subpopulations to establishing and maintaining chronic intestinal inflammation in either of the above entities. It also puts emphasis on the differences in the prevalence of these diseases between Eastern and Western countries.

Key Messages

In celiac disease, the driving role of T cells in the lamina propria and in the epithelium mainly specific for two defined antigens is well established. Differences in genetics and lifestyle between Western and Eastern countries were instrumental in understanding underlying mechanisms. In IBD, the vast amount of potential antigens and the corresponding antigen-specific T cells makes it unlikely to find universal triggers. Increased mucosal CD4⁺ regulatory T cells in all four entities fail to control or abrogate local inflammatory processes. Thus, prevailing differences in the functional T-cell subtypes driving chronic intestinal inflammation in celiac disease and IBD at best allow some overlap in the treatment options for either disease.

Contemporary methods for the diagnosis and treatment of microscopic colitis

Microscopic colitis is a common cause of chronic diarrhea. It is characterized by non-bloody watery diarrhea with macroscopically normal colonic mucosa. Its specific histological characteristics confirm the diagnosis. Two distinct histological forms can be identified, namely, collagenous colitis and lymphocytic colitis. In collagenous colitis, a thick colonic subepithelial collagenous deposit can be observed, whereas in lymphocytic colitis, a pronounced intraepithelial lymphocytic inflammation in the absence of a thickened collagen band can be identified. Microscopic colitis occurs more frequently in elderly females and its etiology is believed to be multifactorial, although smoking and consumption of several drugs have been identified as risks factors for the development of the disease. The treatment is based on avoiding the risks factors and administration of oral budesonide.

Ethnic Distribution of Microscopic Colitis in the United States

BACKGROUND

A large electronic database of histopathology reports was used to study the ethnic distribution of microscopic colitis in the United States.

METHODS

Miraca Life Sciences is a nation-wide pathology laboratory that receives biopsy specimens submitted by 1500 gastroenterologists distributed throughout the United States. In a case-control study, the prevalence of microscopic colitis in 4 ethnic groups (East Asians, Indians, Hispanics, and Jews) was compared with that of all other ethnic groups (composed of American Caucasians and African Americans), serving as reference group.

RESULTS

A total of 11,706 patients with microscopic colitis were included in the analysis. In all ethnic groups alike, microscopic colitis was more common in women than men (78% versus 22%, odds ratio = 3.40, 95% confidence interval = 3.26-3.55). In all ethnic groups, the prevalence of microscopic colitis showed a continuous age-dependent rise. Hispanic patients with microscopic colitis were on average younger than the reference group (59.4 ± 16.2 years versus 64.2 ± 13.8 years, P < 0.001). Jewish patients with microscopic colitis were slightly older than the reference group (65.6 ± 13.4 years, P = 0.015). Compared with the reference group (prevalence = 1.20%), microscopic colitis was significantly less common among patients of Indian (prevalence = 0.28%, odds ratio = 0.32, 95% confidence interval = 0.13-0.65), East Asian (0.22%, 0.19, 0.14-0.26), or Hispanic decent (0.48%, 0.40, 0.36-0.45) and significantly more common among Jewish patients (1.30%, 1.10, 1.01-1.21).

CONCLUSIONS

Microscopic colitis shows striking variations of its occurrence among different ethnic groups. Such variations could point at differences in the exposure to environmental risk factors.

Lower regional and temporal ultraviolet exposure is associated with increased rates and severity of inflammatory bowel disease hospitalisation

BACKGROUND

In the northern hemisphere, the incidence of inflammatory bowel diseases (IBD) has a north-south gradient, suggesting a link between ultraviolet (UV) exposure or vitamin D status and the pathogenesis of IBD.

AIM

To test the association of UV exposure with the rates and severity of IBD hospitalisation.

METHODS

We conducted a retrospective nationwide analysis of 649 932 Crohn's disease (CD), 384 267 ulcerative colitis (UC), and 288 894 297 non-IBD hospitalisations in the US between 1998 and 2010. Mean UV exposure was assigned to each hospitalisation using surface measures from the National Oceanic and Atmospheric Administration. Relative rates across UV exposures were estimated for IBD hospitalisations, prolonged hospitalisations, bowel surgeries and deaths.

RESULTS

Among IBD patients, lower UV exposures had increased hospitalisation rates for CD (217.8 vs. 182.5 per 100 000 overall hospitalisations with low and very high UV, respectively; P trend <0.001) and UC (123.2 vs. 113.8 per 100 000; P trend = 0.033). Low UV groups had greater relative rates of prolonged hospitalisations [CD: 1.13, 95% confidence interval (CI) 1.07-1.19; UC: 1.21, 95% CI 1.13-1.30], bowel surgeries (CD: 1.24, 95% CI 1.16-1.32; UC: 1.21, 95% CI 1.09-1.33), and CD deaths (CD: 1.76, 95% CI 1.14-2.71; UC: 1.24, 95% CI 0.92-1.67). Among non-IBD patients, low UV was associated with prolonged hospitalisations (1.09; 95% CI 1.07-1.11) and deaths (1.13; 95% CI 1.09-1.17), but not bowel surgeries (1.01; 95% CI 0.99-1.03).

CONCLUSIONS

Lower ultraviolet exposure is associated with greater rates of hospitalisation, prolonged hospitalisation and the need for bowel surgery in IBD. This trend for bowel surgery was not seen with non-IBD encounters.

Incidence and paris classification of pediatric inflammatory bowel disease

New epidemiological data suggest that the incidence of inflammatory bowel disease (IBD) is increasing. As a result the burden of disease accounts for more strains to the health care system. The clinical variability queries whether disease characteristics are related to clinical outcome. Our aim was to delineate the latest results of incidence trends in pediatric IBD and to compare the first experiences with Paris Classification. Incidence of pediatric IBD has been increasing in Western Europe and in Eastern Europe. To better characterize IBD, Paris Classification was introduced and validated recently. Ileocolonic involvement is the most characteristic disease location in Crohn's disease (CD) based on applying Paris Classification. The rate of perianal disease and complicated behaviour in CD was similar. It is of interest that CD patients with colonic involvement were less likely to have stricturing disease compared with patients with ileal involvement. In addition, pancolitis dominated in ulcerative colitis (UC). However, most countries lack prospective, nationwide epidemiological studies to estimate incidence trends. This review emphasizes the importance of nationwide registries that enroll all pediatric IBD cases serving reliable data for "everyday practice." These first reports have shown that Paris Classification is a useful tool to determine the pediatric IBD phenotype.

Stable incidence of collagenous colitis and lymphocytic colitis in Örebro, Sweden, 1999-2008: a continuous epidemiologic study

BACKGROUND

The incidence of microscopic colitis (MC) has increased in several centers, but long-term epidemiologic data are missing. We report an epidemiologic study of collagenous colitis (CC) and lymphocytic colitis (LC) during 1999-2008, as a follow-up of our previous studies 1984-1998.

METHODS

Population-based study of residents of the catchment area of the hospital, with a new diagnosis of MC between 1999 and 2008. Patients were identified by diagnosis registers of the Departments of Medicine and Pathology. Medical files were reviewed, and colonic biopsies were reevaluated.

RESULTS

Collagenous colitis was diagnosed in 96 patients (75 females) and LC in 90 patients (74 females). The mean annual age-standardized incidence (per 100,000 inhabitants) was MC 10.2 (95% confidence interval: 8.7-11.7), CC 5.2 (4.2-6.3), and LC 5.0 (4.0-6.0). Age-specific incidence showed a peak in females older than 70 years. Prevalence (per 100,000 inhabitants) on December 31, 2008, was MC 123 (107.6-140.0), CC 67.7 (56.4-80.6), and LC 55.3 (45.2-67.1). A comparison of current study period with 1993-1998 showed unchanged mean incidence of MC, but a 2-fold increase in women older than 60 years with LC (standardized rate ratios 2.2, [1.2-3.7]) and increased female to male ratio (4.6:1 versus 2.1:1; P = 0.02) in LC.

CONCLUSIONS

After an initial rise during 1980s and early 1990s, annual incidence of CC and LC has been stable during the last 15 years around 5/100,000 inhabitants for each disorder. The increasing incidence in older women with LC may be related to an increasing proportion of older individuals in the background population and increased colonoscopy frequency in elderly.

Linking vitamin d deficiency to inflammatory bowel disease

Inflammatory bowel disease is associated with industrialization, and its incidence has increased markedly over time. The prospect of reversing these trends motivates the search for the agent(s) involved. Modernity entails several physical and behavioral modifications that compromise both the photosynthesis of cholecalciferol in the skin and of its bioavailability. Although deficiency in this "vitamin" has therefore emerged as a leading candidate, and despite the publication of a randomized control trial that showed a trend toward statistically significant benefit in Crohn's disease, its causal agency has yet to be demonstrated by an adequately powered study. We discuss the strengths and weaknesses of the case being made by epidemiologists, geneticists, clinicians, and basic researchers, and consolidate their findings into a model that provides mechanistic plausibility to the claim. Specifically, converging data sets suggest that local activation of vitamin D coordinates the activity of the innate and adaptive arms of immunity, and of the intestinal epithelium, in a manner that promotes barrier integrity, facilitates the clearance of translocated flora, and diverts CD4 T cell development away from inflammatory phenotypes. Because smoking is an important risk-altering exposure, we also discuss its newly established melanizing effect and other emerging evidence linking tobacco use to immune function through vitamin D pathways.

High and increasing prevalence of inflammatory bowel disease in Finland with a clear North-South difference

BACKGROUND AND AIM

Inflammatory bowel disease (IBD) prevalence has increased and a North-South gradient has been reported. We estimated the nationwide prevalence of IBD, ulcerative colitis (UC) and Crohn's disease (CD) in 1993, and prevalence of IBD in 2008, and assessed the geographical distribution of IBD in Finland. In addition, we investigated the vitamin D levels in a study population from a large, nationally representative health examination survey, the Health 2000 Survey.

METHODS

The register study for prevalences included all patients who had special reimbursement of medications for IBD in the years 1993 (n=10,958) and 2008 (31,703). The study for D-vitamin measurement consisted of 6134 persons who had participated in the Health 2000 Survey.

RESULTS

The nationwide point prevalence of IBD in 1993 was 216 per 100,000 inhabitants, and 595 in 2008. In 1993, the prevalence of UC (177) was fourfold higher than the prevalence of CD (38). The prevalence of IBD and UC in Finland increased from South to North. For CD, no geographical variation could be demonstrated. In the Health 2000 survey, vitamin D levels were lower in Northern than in Southern Finland.

CONCLUSIONS

Finland belongs to high prevalence area of IBD and this prevalence has increased nearly threefold during the past 15 years. A clear North-South gradient has been shown for IBD and UC, but not for CD. Slightly lower vitamin D levels in Northern Finland may be associated with the observed higher prevalence of IBD there.

Microscopic colitis: epidemiology, pathophysiology, diagnosis and current management-an update 2013

Microscopic colitis is a common cause of chronic diarrhea. Over the last years the incidence and the prevalence of microscopic colitis are rising and this rise is largely attributed to a rising awareness, and concomitantly an increasing number of diagnoses are made. Patients with microscopic colitis report watery, nonbloody diarrhea of chronic, intermittent, or chronic recurrent course. Following an unremarkable physical examination the diagnosis of microscopic colitis is made by colonoscopy, which shows essentially a normal colonic mucosa. Biopsies taken during the colonoscopy procedure will then finally establish the correct diagnosis. Histological workup can then confirm a diagnosis of microscopic colitis and can distinguish the two distinct histological forms, namely, collagenous colitis and lymphocytic colitis. Presently both forms are diagnosed and treated in the same way; thus the description of the two forms is not of clinical value, though this may change in future. Depending on the patients age and gender 10-30% of patients investigated for chronic diarrhea will be diagnosed with microscopic colitis if biopsies are taken. Microscopic colitis is most common in older patients, especially in female patients and is frequently associated with autoimmune disorders and the consumption of several drugs. This review summarizes the present knowledge of the epidemiology, the pathophysiology, and the diagnosis of microscopic colitis and discusses the former and the present treatment options.

Microscopic colitis: Current status, present and future challenges: statements of the European Microscopic Colitis Group

Microscopic colitis (MC) is an inflammatory bowel disease presenting with chronic, non-bloody watery diarrhoea and few or no endoscopic abnormalities. The histological examination reveals mainly two subtypes of MC, lymphocytic or collagenous colitis. Despite the fact that the incidence in MC has been rising over the last decades, research has been sparse and our knowledge about MC remains limited. Specialists in the field have initiated the European Microscopic Colitis Group (EMCG) with the primary goal to create awareness on MC. The EMCG is furthermore a forum with the intention to promote clinical and basic research. In this article statements and comments are given that all members of the EMCG have considered being of importance for a better understanding of MC. The paper focuses on the newest updates in epidemiology, symptoms and diagnostic criteria, pathophysiology and highlights some unsolved problems. Moreover, a new treatment algorithm is proposed on the basis of new evidence from well-designed, randomized control trials.