Prevalence and Natural History of Microscopic Colitis: A Population-Based Study With Long-term Clinical Follow-up in Terrassa, Spain

Microscopic colitis: Etiopathology, diagnosis, and rational management

Microscopic colitis is an inflammatory bowel disease divided into two subtypes: collagenous colitis and lymphocytic colitis. With an increasing incidence of microscopic colitis exceeding those of ulcerative and Crohn's disease among elderly people in some countries, microscopic colitis is a debilitating life experience. Therefore, physicians should be familiar with its clinical features and management strategies because the disease deserves the same attention as the classical inflammatory bowel diseases. Here, state-of-the-art knowledge of microscopic colitis is provided from a global perspective with reference to etiopathology and how to establish the diagnosis with the overall aim to create awareness and improve rational management in clinical practice. The immune system and a dysregulated immune response seem to play a key role combined with risk factors (e.g. cigarette smoking) in genetically predisposed individuals. The symptoms are characterized by recurrent or chronic nonbloody, watery diarrhea, urgency, weight loss, and a female preponderance. As biomarkers are absent, the diagnosis relies on colonoscopy with a histological assessment of biopsy specimens from all parts of the colon. Although the disease is not associated with a risk of colorectal cancer, a recent nationwide, population-based cohort study found an increased risk of lymphoma and lung cancer. Budesonide is the first-line therapy for management, whereas immunomodulatory drugs (including biologics) and drugs with antidiarrheal properties may be indicated in those failing, dependent, or intolerant to budesonide. In microscopic colitis induced by checkpoint inhibitors, a drug class used increasingly for a wide range of malignancies, a more aggressive therapeutic approach with biologics introduced early seems reasonable. However, particular attention needs to be drawn to the existence of incomplete forms of microscopic colitis with the risk of being overlooked in routine clinical settings.

The Epidemiology of Microscopic Colitis in Olmsted County, Minnesota: Population-Based Study From 2011 to 2019

BACKGROUND & AIMS

Epidemiologic studies from Europe and North America have reported an increasing incidence of microscopic colitis (MC) in the late 20th century, followed by a plateau. This population-based study assessed recent incidence trends and the overall prevalence of MC over the past decade.

METHODS

Residents of Olmsted County, MN, diagnosed with collagenous colitis (CC) or lymphocytic colitis (LC) between January 1, 2011, and December 31, 2019 were identified using the Rochester Epidemiology Project. Clinical variables were abstracted by chart review. Incidence rates were age- and sex-adjusted to the 2010 US population. Associations between incidence and age, sex, and calendar periods were evaluated using Poisson regression analyses.

RESULTS

A total of 268 incident cases of MC were identified with a median age at diagnosis of 64 years (range, 19-90 y); 207 (77%) were women. The age- and sex-adjusted incidence of MC was 25.8 (95% CI, 22.7-28.9) cases per 100,000 person-years. The incidence of LC was 15.8 (95% CI, 13.4-18.2) and CC was 9.9 (95% CI, 8.1-11.9) per 100,000 person-years. A higher MC incidence was associated with increasing age and female sex (P < .01). There was no significant trend in age- and sex-adjusted incidence rate over the study period (P = .92). On December 31, 2019, the prevalence of MC, LC, and CC (including cases diagnosed before 2011) was 246.2, 146.1, and 100.1 per 100,000 persons, respectively.

CONCLUSIONS

The incidence of MC and its subtypes was stable between 2011 and 2019, but its prevalence was higher than in previous periods. The incidence of MC continues to be associated with increasing age and female sex.

Microscopic Colitis in Denmark: Regional Variations in Risk Factors and Frequency of Endoscopic Procedures

OBJECTIVE

Microscopic colitis [MC], encompassing collagenous colitis [CC] and lymphocytic colitis [LC], is an increasingly prevalent gastrointestinal disease with an unknown aetiology. Previous research has reported significant differences in the incidence of MC within Denmark, with the lowest incidence found in the most populated region [Capital Region of Denmark]. Our aim was to elucidate the causes of these regional differences.

DESIGN

All incident MC patients [n = 14 302] with a recorded diagnosis of CC [n = 8437] or LC [n = 5865] entered in The Danish Pathology Register between 2001 and 2016 were matched to 10 reference individuals [n = 142 481]. Information regarding drug exposure, including proton pump inhibitors [PPIs], selective serotonin reuptake inhibitors [SSRIs], statins, and nonsteroidal anti-inflammatory drugs [NSAIDs], were retrieved from The Danish National Prescription Registry. Information regarding endoscopy rate, smoking-related diseases, and immune-mediated inflammatory diseases were acquired from The Danish National Patient Registry.

RESULTS

Smoking, immune-mediated inflammatory diseases, exposure to PPIs, SSRIs, statins, and NSAIDs were significantly associated with MC in all Danish regions. The association between drug exposure and MC was weakest in the Capital Region of Denmark with an odds ratio of 1.8 (95% confidence interval [CI]: 1.61-2.01). The relative risk of undergoing a colonoscopy with biopsy was significantly increased in sex- and age-matched controls in all regions compared with controls from the Capital Region of Denmark, with the greatest risk found in the Region of Southern Denmark, 1.37 [95% CI: 1.26-1.50].

CONCLUSIONS

The cause of the regional differences in MC incidence in Denmark seems to be multifactorial, including variations in disease awareness and distribution of risk factors.

Course of Disease in Patients with Microscopic Colitis: A European Prospective Incident Cohort Study

BACKGROUND AND AIMS

The disease course of microscopic colitis [MC] is considered chronic but benign. However, this assumption is based on mainly retrospective studies, reporting on incomplete follow-up of selective cohorts. Systematic, prospective and unbiased data to inform patients and healthcare professionals on the expected course of the disease and real-life response to therapy are warranted.

METHODS

A prospective, pan-European, multi-centre, web-based registry was established. Incident cases of MC were included. Data on patient characteristics, symptoms, treatment and quality of life were systematically registered at baseline and during real-time follow-up. Four disease course phenotypes were discriminated and described.

RESULTS

Among 381 cases with complete 1-year follow-up, 49% had a chronic active or relapsing disease course, 40% achieved sustained remission after treatment and 11% had a quiescent course. In general, symptoms and quality of life improved after 3 months of follow-up. A relapsing or chronic active disease course was associated with significantly more symptoms and impaired quality of life after 1 year.

CONCLUSIONS

A minority of MC patients follow a quiescent disease course with spontaneous clinical improvement, whereas the majority suffer a chronic active or relapsing disease course during the first year after diagnosis, with persisting symptoms accompanied by a significantly impaired quality of life.

European guidelines on microscopic colitis: United European Gastroenterology and European Microscopic Colitis Group statements and recommendations

INTRODUCTION

Microscopic colitis is a chronic inflammatory bowel disease characterised by normal or almost normal endoscopic appearance of the colon, chronic watery, nonbloody diarrhoea and distinct histological abnormalities, which identify three histological subtypes, the collagenous colitis, the lymphocytic colitis and the incomplete microscopic colitis. With ongoing uncertainties and new developments in the clinical management of microscopic colitis, there is a need for evidence-based guidelines to improve the medical care of patients suffering from this disorder.

METHODS

Guidelines were developed by members from the European Microscopic Colitis Group and United European Gastroenterology in accordance with the Appraisal of Guidelines for Research and Evaluation II instrument. Following a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the certainty of the evidence. Statements and recommendations were developed by working groups consisting of gastroenterologists, pathologists and basic scientists, and voted upon using the Delphi method.

RESULTS

These guidelines provide information on epidemiology and risk factors of microscopic colitis, as well as evidence-based statements and recommendations on diagnostic criteria and treatment options, including oral budesonide, bile acid binders, immunomodulators and biologics. Recommendations on the clinical management of microscopic colitis are provided based on evidence, expert opinion and best clinical practice.

CONCLUSION

These guidelines may support clinicians worldwide to improve the clinical management of patients with microscopic colitis.

Epidemiological and clinical characteristics, and response to treatment in 113 patients with microscopic colitis

OBJECTIVE

To study the epidemiological and clinical characteristics, and response to treatment in patients with microscopic colitis.

PATIENTS AND METHOD

Epidemiological, clinical, blood test and endoscopic data were retrospectively collected from 113 patients with microscopic colitis. Response to treatment was analyzed in 104 of them. Efficacy and relapse after treatment with budesonide were assessed using survival curves (Kaplan-Meier).

RESULTS

78% of the patients were women, with a mean age of 65 ± 16 years. In smokers, the mean age was 10 years younger. 48% of them had some concomitant autoimmune disease; 60% suffered a single outbreak of the disease. The clinical presentation was similar in both subtypes, although patients with collagenous colitis had a chronic course more frequently (48% vs. 29%, p = 0.047). The remission rate with budesonide was 93% (95% CI 82-98). The cumulative incidence of relapse, after a median follow-up of 21 months, was 39% (95% CI 26-54%): 19% at one year, 32% at two years, and 46% at three years of follow-up. There were no differences in clinical response to budesonide based on smoking habit or microscopic colitis subtype.

CONCLUSIONS

Microscopic colitis is more frequent in elderly women. Smoking was associated with earlier onset of the disease, although it did not influence the clinical course or response to treatment. The majority (> 90%) of patients treated with budesonide achieved remission, although nearly half subsequently relapsed.

Irritable bowel syndrome-like symptoms in treated microscopic colitis patients compared with controls: a cross-sectional study

Background

The prevalence of irritable bowel syndrome (IBS)-like symptoms is high in untreated patients with microscopic colitis (MC), but there is uncertainty of the prevalence of IBS-like symptoms in treated patients. We assessed the degree of IBS-like symptoms in patients with MC in comparison to control subjects, and investigated the association between IBS-like symptoms and faecal calprotectin (FC) in MC patients.

Methods

Patients with an established MC diagnosis (n = 57) were compared to sex- and age-matched controls (n = 138) for scores in the GSRS-IBS (Gastrointestinal Symptom Rating Scale for Irritable Bowel Syndrome) and HADS (Hospital Anxiety Depression Scale). In MC patients, an FC level was simultaneously analysed.

Results

The median interval from MC diagnoses to the time the subjects participated in the study was 5.5 years (25th–75th percentiles; 4.5–9.5 years). The total GSRS-IBS score, subscores for abdominal pain, bloating, and diarrhoea were significantly higher in MC patients compared to controls (all P < 0.001). There was a significant correlation between FC levels and reported bowel frequency (P = 0.023), but there was no correlation between FC levels and GSRS-IBS scores. Patients with MC had significantly higher scores on anxiety (HADS-A) (P < 0.001) and used more selective serotonin-reuptake-inhibitor drugs (P = 0.016) than the control subjects. However, only the control subjects (not the patients with MC) showed significant correlations between GSRS-IBS scores and HADS scores.

Conclusions

Patients with MC reported more IBS-like symptoms and anxiety than control subjects but neither FC levels nor symptoms of affectivity were significantly correlated with IBS-like symptoms.

Mortality of Patients With Microscopic Colitis in Sweden

BACKGROUND & AIMS

Microscopic colitis is one of the most common causes of chronic diarrhea in older populations. We investigated all-cause and cause-specific mortality in patients with microscopic colitis.

METHODS

We conducted a nationwide cohort study of all cases of microscopic colitis (n = 14,333) diagnosed from 1990 through 2017 in Sweden. Cases of microscopic colitis were identified using SNOMED codes from gastrointestinal histopathology reports collected from Sweden's 28 pathology departments. Each case of microscopic colitis was matched to 5 population comparators (n = 68,700). Mortality data were ascertained from Sweden's cause of death register. We used Cox proportional hazards modeling to estimate adjusted hazard ratios (aHRs) and 95% CIs.

RESULTS

Through December of 2017, we confirmed 3014 deaths in patients with microscopic colitis (27.4/1000 person-years) and 12,534 deaths in matched population comparators (23.3/1000 person-years). This corresponded to a 10-year absolute risk difference of 3.4% (95% CI, 2.1%-4.6%) and an aHR of 1.17 (95% CI, 1.12-1.22). However, further adjustment of models for comorbidity burden reduced the relative risk of death for patients with microscopic colitis (aHR, 0.98; 95% CI, 0.94-1.02). In analyses of cause-specific death, microscopic colitis was associated with an increased risk of gastrointestinal-related death (aHR, 1.68; 95% CI, 1.38-2.05) and infection-related death (aHR, 1.42 ; 95% CI, 1.11-1.83), but not cancer-related death (aHR, 0.83; 95% CI, 0.76-0.91) or cardiovascular-related death (aHR, 1.02; 95% CI, 0.96-1.10).

CONCLUSIONS

In a nationwide cohort study in Sweden, we found that patients with microscopic colitis were at increased risk of death. However, the increase appears to be related to higher burden of comorbidities in this population.

All-cause and cause-specific mortality in microscopic colitis: a Danish nationwide matched cohort study

BACKGROUND

The long-term natural history of microscopic colitis remains uncertain.

AIM

To describe the mortality in a large unselected cohort of patients with microscopic colitis.

METHODS

All Danish patients above 18 years with an incident diagnosis of microscopic colitis from 2001 to 2018 were identified from nationwide registries and compared to age- and sex-matched controls (variable 1:10 ratio). Patients were categorised according to subtypes: lymphocytic colitis and collagenous colitis. The relative risk of death by any cause was analysed with Cox regression models estimating both crude and comorbidity-adjusted hazard ratios (HRs) with 95% confidence intervals (CIs). Cause-specific death was evaluated with cumulative incidence functions. An E-value was calculated to address the impact of unmeasured confounding.

RESULTS

The final cohort consisted of 14 024 patients with microscopic colitis. The mean follow-up was 5.8 (standard deviation SD, 2.9) years and the mean age at diagnosis was 61.1 (SD 13.9) years, 70% were women and 41% were diagnosed with lymphocytic colitis. The main results showed a 25% increased risk of all-cause death in patients with microscopic colitis; however, the relative risk was attenuated to 9% when adjusting for comorbidities (95% CI, 1.05-1.14). The E-value indicates that unmeasured confounding could explain the residual observed increased all-cause mortality. Mortality was significantly increased in patients with both lymphocytic colitis (HR 1.15; 95% CI, 1.08-1.23) and collagenous colitis (HR 1.06; 95% CI, 1.01-1.12) in fully adjusted analyses. The absolute difference in death between patients with microscopic colitis and matches was 0.9% at 1 year, 2.8% at 5 years, 5.0% at 10 years and 3.0% at 15 years. Cumulative incidence functions showed that patients with microscopic colitis were more likely to die due to smoking-related diseases including ischemic heart and lung diseases, but had a significant decreased risk of death due to colorectal cancers (P < 0.0001).

CONCLUSION

In an unselected large nationwide cohort of patients with microscopic colitis, the risk of death was significantly increased compared to the background population. However, the increased mortality seemed to be associated to a high burden of comorbidities and unmeasured life-style factors including smoking and not microscopic colitis per se.

Usefulness of fecal calprotectin as a biomarker of microscopic colitis in a cohort of patients with chronic watery diarrhoea of functional characteristics

BACKGROUND

Information on the use of fecal markers in microscopic colitis screening is limited.

AIM

To evaluate the risk variables associated with a diagnosis of microscopic colitis including fecal calprotectin.

METHODS

Patients submitted for a colonoscopy due to chronic watery diarrhea fulfilling criteria of functional disease were evaluated. Colonic mucosa was normal but mild erythema and edema was allowed. Fecal calprotectin was analyzed. A logistic regression was used to evaluate variables associated with both raised fecal calprotectin and a diagnosis of microscopic colitis.

RESULTS

94 patients were included, 30 were diagnosed with microscopic colitis and 64 made up the control group. Median calprotectin levels were 175 (IQR, 59-325) for the microscopic colitis and 28 (IQR, 16-111) for the control group (p < 0.001). The optimal cut-off for fecal calprotectin was >100 μg/g (AUC, 0.73), with 67% sensitivity and 75% specificity. The number of drugs used ≥3 (OR, 3.9; CI, 1.4-10.4) and microscopic colitis diagnosis (OR, 6; CI, 2.2-16.3) were associated with raised calprotectin levels. Age >60 years (OR, 3.8; CI, 1.4-10.1) and calprotectin levels (OR, 5.3; CI, 2-14.1) were associated with a risk of microscopic colitis.

CONCLUSIONS

Elevated fecal calprotectin concentrations are often seen in microscopic colitis, and may be helpful in the diagnosis of women over 60 with chronic watery diarrhea.

Management of microscopic colitis: challenges and solutions

Microscopic colitis (MC) is a chronic inflammatory bowel disease characterized by nonbloody diarrhea in the setting of normal appearing colonic mucosa. MC has two main subtypes based on histopathologic features, collagenous colitis and lymphocytic colitis. Management of both subtypes is the same, with treatment goal of reducing the number of bowel movements and improving consistency. First-line treatment involves counseling the patient about decreasing their risk factors, like discontinuing smoking and avoiding medications with suspected association such as NSAIDs, proton pump inhibitor, ranitidine, and sertraline. Starting loperamide for immediate symptomatic relief is used as an adjunct to therapy with glucocorticoids. Budesonide is considered first-line treatment for MC given its favorable side effect profile and good efficacy, though relapse rates are high. Systemic glucocorticoids should be reserved to patients unable to take budesonide. In glucocorticoid refractory disease, medications that have been tried include cholestyramine, bismuth salicylate, antibiotics, probiotics, aminosalicylates, immunomodulators, and anti-tumor necrosis factor-alpha inhibitors. More research is needed for the creation of a systematic stepwise approach for relapsing and refractory disease.