Risk factors for colon ischemia

Case Report: A case of perirectal abscess complicated with rectal necrosis

Rectal necrosis represents the extreme progression of ischemic proctitis. Given the unique blood supply of the rectum, which features an extensive collateral circulation, cases of rectal necrosis are extremely rare, accounting for 2%-5% of the ischemic colitis cases. The etiology and pathogenesis of rectal necrosis encompass acute vascular occlusion, severe vascular diseases, low blood flow states, and factors such as radiotherapy, vasculitis, and mesenteric venous myointimal hyperplasia. Herein, we report a rare case of perirectal abscess complicated by rectal necrosis at the Anorectal Surgery Department of Bao'an Traditional Chinese Medicine Hospital in Shenzhen. The patient underwent a one-stage incision and drainage for a rectal abscess, followed by sigmoid colostomy and a two-stage reversal of the sigmoid colostomy; all procedures were performed through multidisciplinary collaboration. The surgical outcome was favorable after a 6-month follow-up.

Precision medicine in intestinal ischemia: the emerging role of biomarkers

Intestinal ischemia (IIs) is a significant gastrointestinal condition characterized by reduced blood flow to the bowel, leading to inflammation and injury. Early diagnosis and management are crucial for preventing severe complications. Under this point of view, circulating biomarkers can enhance patient stratification and guide therapeutic decisions. Fatty acid-binding proteins (FABPs), specifically I-FABP and L-FABP, are small cytosolic proteins released upon enterocyte membrane integrity loss, with elevated plasma levels indicating early intestinal ischemia. Stromal Cell-Derived Factor-1 (SDF-1) regulates stem cell function and shows significantly higher levels in patients with IIs and cardiovascular disease compared to controls. D-Lactate, a bacterial fermentation byproduct, is another significant marker, with higher serum levels observed in intestinal ischemia cases. Alpha-glutathione S-transferase combats intracellular oxidative stress, with significantly elevated levels in acute mesenteric ischemia patients. Additionally, SM22, a small smooth muscle protein, shows higher plasma levels in patients with transmural ischemia compared to those with mucosal ischemic lesions and healthy controls. These biomarkers are promising for their roles in early detection and differentiation of IIs from other gastrointestinal conditions. Therapeutic strategies, including anti-inflammatory therapies, have shown efficacy in managing IIs symptoms and preventing recurrence. This review aims to inform clinicians and researchers about the current advancements in biomarker research and therapeutic approaches for IIs, emphasizing the importance of integrating these biomarkers and treatments into clinical practice to improve the management and prognosis of the disease.

Semaglutide-Associated Ischemic Colitis in a Patient Without Traditional Risk Factors: A Case Report

This report describes the case of a 43-year-old female patient presenting with left lower quadrant pain and bloody diarrhea, initially managed as infectious colitis. Despite treatment, symptoms persisted, leading to repeat imaging showing mild pancolitis with colon mucosal hyperenhancement and wall thickening. Admission for intravenous hydration and subsequent colonoscopy revealed findings consistent with ischemic colitis. Semaglutide (Ozempic), which the patient had been taking, was discontinued, and symptoms resolved post discharge without semaglutide use for several months. This suggests a potential association between semaglutide and ischemic colitis in a patient without known risk factors. This case underscores the importance of considering medication-induced colitis in patients presenting with persistent gastrointestinal symptoms, particularly in the absence of typical risk factors.

Prior appendectomy and cerebral infarction as potential risk factors for recurrent ischemic colitis: A retrospective observational study

Background and Aim

Ischemic colitis (IC) is a benign disease associated with acute lower gastrointestinal bleeding and frequent recurrence. While several studies have investigated risk factors for IC onset, few have assessed the risk factors for recurrent IC. This study aimed to identify risk factors for recurrent IC.

Methods

Potential risk factors for recurrence were assessed by examining medical records and laboratory findings in this single-center retrospective study. We extracted the following data from the patients' medical records: patient characteristics, clinical signs and symptoms, laboratory findings, method of treatment, length of hospital stay, disease course, and the frequency of IC morbidities. Patients with IC were selected from a total of 439 312 patients over an 11-year period. Patients were divided into recurrent and nonrecurrent IC groups.

Results

In total, 225 patients met the diagnostic criteria for IC during the specified study period; of these, 204 patients (90.7%) and 21 patients (9.3%) were included in the nonrecurrent and recurrent IC groups, respectively. Univariate and multivariate analyses showed a significant association between IC recurrence and both cerebral infarction (P = 0.008, odds ratio [OR] = 6.3) and history of appendectomy (P = 0.0005, OR = 6.2). The median (interquartile range [IQR]) follow-up time for all patients was 1556 (353-2768) days; this was much longer than the median (IQR) time to recurrence of 291 (64-907) days in the recurrent IC group.

Conclusion

The results of this study suggest that prior cerebral infarction and appendicectomy may be risk factors for IC recurrence.

The association between irritable bowel syndrome and ischemic colitis: a systematic review and meta-analysis

INTRODUCTION

Studies have suggested an association between ischemic colitis and irritable bowel syndrome (IBS) although the results were inconsistent. This systematic review and meta-analysis were performed to comprehensively examine the association between IBS and ischemic colitis by identifying all available cohort and case-control studies and combining their effect estimates together.

EVIDENCE ACQUISITION

EMBASE, MEDLINE and Google Scholar databases were systematically reviewed up to June 2020. Eligible study had to be either cohort or case-control studies that evaluated whether patients with IBS have a higher risk of ischemic colitis than individuals without IBS. Point estimates and standard errors from each eligible study were combined together using the generic inverse variance method of DerSimonian and Laird.

EVIDENCE SYNTHESIS

The systematic review identified three cohort and eight case-control studies. The pooled analysis found a significantly higher risk of ischemic colitis among patient with IBS with the pooled odds ratio of 2.50 (95% CI, 2.00-3.14; I² 57%). Funnel plot was relatively symmetric and was not suggestive of presence of publication bias.

CONCLUSIONS

A significantly increased risk of ischemic colitis among patients with IBS was observed in this systematic review and meta-analysis.

Clinical features and risk factors for ischemic colitis in young and middle-aged patients

Background and study aims: Ischemic colitis (IC) is thought to occur more frequently in the elderly, but the incidence in young and middle-aged adults is increasing. This study determined the clinical characteristics of and risk factors for young and middle- aged IC patients. Patients and methods: The medical records of 190 IC patients from 2010-2020 were reviewed. The clinical features of the young and middle-aged IC group (group A, < 60 years [n=70]) were compared to the elderly IC (group B, ≥60 years [n=120]) and age- and gender-matched colon polyp groups (group C, <60 years [n=272]). Independent risk factors for IC in group A were assessed using multivariate logistic regression analysis. Results: There were no significant differences in groups A and B with respect to season of onset, symptoms, signs, treatment, or recurrences. The main symptoms of group A were abdominal pain (98.6%) and hematochezia (98.6%). Lesions commonly involved the left half of the colon (87.1%) and the clinical conditions were generally not severe. The percentage of patients with constipation (11.4% vs. 4.0%, P=0.034) and using a calcium channel antagonist (21.4% vs. 11.4%, P=0.028) was significantly higher in group A than group C. Regression analysis demonstrated that constipation (OR 2.831, P=0.037) and taking a calcium channel antagonist (OR 2.486, P=0.012) were closely associated with the occurrence of IC in group A. Conclusions: Constipation and taking a calcium channel antagonist were independent risk factors for the onset of IC in young and middle-aged adults. Among young and middle-aged adults with abdominal pain and bloody stools who also have constipation or are taking a calcium channel antagonist to treat hypertension, the diagnosis of IC should be considered.

Severe acute ischemic colitis: What is the place of endoscopy in the management strategy?

Background and study aims  Ischemic colitis (IC) is potentially lethal. Clinical and biology information and results of computed tomography (CT) scan and/or colonoscopy are used to assess its severity. However, decision-making about therapy remains a challenge. Patients and methods  This was a retrospective, single-center study between 2006 and 2015. Patients with severe IC who underwent endoscopic evaluation were included. The aims were to determine outcomes depending on endoscopic findings and assess the role of endoscopy in the management. Results  A total of 71 patients were included (men = 48 (68%), mean age = 71 ± 13 years). There was hemodynamic instability in 29 patients (41 %) and severity signs on CT scan in 18 (38 %). Twenty-nine patients (41 %) underwent surgery and 24 (34 %) died. The endoscopic grades were: 15 grade 1 (21 %), 32 grade 2 (45 %), and 24 grade 3 (34%). Regarding patients with grade 3 IC, 55 % had hemodynamic instability, 58 % had severity signs on CT scan, 68 % underwent surgery, and 55 % died. The decision to perform surgery was based on hemodynamic status in 62 % of cases, CT scan data in 14 %, endoscopic findings in 10 %, and other in 14 %. Colectomy was more frequent in patients with grade 3 IC ( P  < 0.05). A mismatch between mucosal aspect (necrosis) and serous (normal) was observed in 13 patients (46 %). Risk factors for colectomy in univariate analysis were aortic aneurysm surgery, hemodynamic instability, no colic enhancement on CT scan, and endoscopic grade 3. Risk factors for mortality in multivariate analysis were hemodynamic instability, colectomy, and Charlson score > 5 ( P  < 0.05). Conclusions  This study suggests a low impact of endoscopy on surgical decision making. Hemodynamic instability was the first indication for colectomy. A discrepancy between endoscopic mucosal (necrosis) and surgical serous (normal) aspects was frequently noted.

Colon ischemia: A comprehensive review

The clinical and endoscopic features of colon ischemia (CI) are non-specific. CI is correctly identified at the time of presentation in only 9% of patients is. The true incidence is likely underestimated because many mild cases resolve spontaneously without medical treatment. Furthermore, since most cases of CI are transient, and no specific cause is detected they are often considered to be "idiopathic". In the setting of severe CI correct diagnosis and prompt recognition and therapy as well as identification of underlying causes are crucial for a favourable outcome. Although less severe, mild cases may present with similar symptoms, the prognosis and management are completely different and managed conservatively rather than with surgery. Unfortunately, data from most studies and current guidelines do not provide recommendations on the long-term management of CI or about the need for endoscopic follow-up to detect the development chronic, recurrent and/or ischemic colonic strictures. In this review, we focus on the definition of CI, its aetiology, and patterns of presentation. We highlight the pharmacological and/or endoscopic management as determined severity of disease that allow for improved outcomes. Prompt recognition and treatment using a multidisciplinary approach are essential for successful management of severe CI because mortality rates are significantly higher when the diagnosis is delayed.

Drug-Induced Colitis

Drug-induced colitis encompasses a wide spectrum of colon disorders that can manifest microscopically or macroscopically. Patients present with new-onset colitis or exacerbations of inflammatory bowel diseases; in some cases, colitis resolves with discontinuation of medication. Mucosal injury can be focal or extensive, involving the entire colonic mucosa, and sometimes involves other parts of the gastrointestinal tract. It has been a challenge to determine the proportion of new-onset colitis caused by medication and there are few data on the overall prevalence. We review the drugs that have been linked with development of drug-induced colitis and strategies for physicians who believe their patients have this disorder-usually discontinuation of the drug believed to cause colitis and treatment with steroids or immune-modulating therapies. Physicians must be aware of medications that can cause colitis.

Homozygous Factor V Leiden presenting as irreversible chronic colon ischemia resulting from inferior mesenteric vein thrombosis

A 42-year-old man presented with 6 months of unexplained left lower quadrant abdominal pain and hematochezia accompanied by weight loss despite extensive evaluations. Stool studies for pathogens were unrevealing, but an abdominal contrast-enhanced computed tomography revealed findings of chronic inferior mesenteric vein thrombosis. Colonoscopy demonstrated ulcerated strictures and gangrene confined to the sigmoid and descending colons, and biopsies confirmed changes of chronic irreversible colon ischemia. A homozygous Factor V Leiden mutation was diagnosed. The patient underwent colectomy and was treated with lifelong anticoagulation. While mesenteric venous thrombosis is a well-recognized cause of colon ischemia in hypercoagulable states, thrombosis of the inferior mesenteric vein is uncommon; when chronic it is rarely clinically apparent. Similarly, while Factor V Leiden mutation is a common hereditary thrombophilia, it uncommonly causes mesenteric venous thrombosis, and homozygotes of the mutation typically present earlier in the fourth decade and with non-mesenteric venous thromboembolism. This case is valuable and adds to the existing literature in describing a rare, clinically atypical, and late index presentation of homozygous Factor V Leiden mutation as chronic inferior mesenteric vein thrombosis yielding irreversible colon ischemia.

Leukocytes and creatinine may predict severity and guide management of ischemic colitis

BACKGROUND

Ischemic colitis (IC) is caused by a transient hypo-perfusion of the colon leading to mucosal ulcerations, inflammation, and hemorrhage. The primary aim was to identify predictive factors of endoscopic severity of IC. Secondary endpoints were to show epidemiology, clinical presentation, endoscopic findings, and outcomes of IC.

METHODS

In this single-center retrospective analysis, IC was scored according to endoscopy as: grade 1 (hyperemia, <1 cm erosions and non-confluent ulcers); grade 2 (>1 cm superficial, partially confluent ulcers); and grade 3 (deep or diffuse ulcers or necrosis). Then, IC was grouped into low- (grade 1) and high-grade (grades 2 and 3). Significant (P≤0.1) independent factor of severe IC at univariate analysis were entered into multivariate analysis and considered significant at P<0.05.

RESULTS

227 patients (male:female 60:167; mean age 72.7±16.2 years) were included. IC was scored as grade 1 in 137/227 (60.4%), grade 2 in 62/227 (27.3%), and grade 3 in 28/227 (12.3%) patients. At univariate analysis, age (74.9 vs. 71.3 years; P=0.09), diabetes (14.4% vs. 12.4%; P=0.09), and leukocytosis or creatinine elevation (74.4% vs. 60.6%; P=0.032) were associated with endoscopic high-grade IC. At multivariate analysis, leukocytosis and creatinine levels remained associated with high-grade IC (44.7% vs. 29.9%; odds ratio 1.92, 95% confidence interval 1.07-3.52; P=0.030).

CONCLUSIONS

Although confounding factors cannot be excluded due to study design and patients' characteristics, leukocytosis and/or creatinine elevation at hospital admission were significantly related with endoscopic high-grade IC and might be used to stratify patients for the need of endoscopy.

Quantifying risk factors for ischemic colitis: A nationwide, retrospective cohort study

BACKGROUND

Despite identifying numerous factors associated with colonic ischemia, the relative risk has been variable and not thoroughly evaluated. Hence, we aimed to quantify the risk of diseases and medications associated with ischemic colitis (IC).

METHODS

A population-based retrospective analysis in International Business Machines (IBM) Explorys (1999-2018), a pooled, de-identified database of 57 million patients in the USA, was performed. Odds ratios (OR) were calculated between IC and other diseases/medications. IC patients were also stratified by age to assess trends of IC in different age groups.

RESULTS

A total of 1560 patients had IC in the database. Hyperlipidemia had the highest association with IC (OR 15.3), consistent with prior reports of atherosclerosis being a major risk factor for IC. Hypertension, congestive heart failure, constipation, prior abdominal surgery, and atrial fibrillation all conferred odds greater than 10, which is consistent with prior reports. Novel findings of our study include that beta blockers (OR 9.6) and pro-inflammatory disease states such as vasculitis, rheumatoid arthritis, and malignancy all increase the risk of IC.

CONCLUSION

Early identification of IC is critical for minimizing morbidity and mortality. Epidemiologic information could be integrated with current clinical algorithms to more rapidly identify patients at risk.

A case of stricture-type ischemic colitis from excessive alcohol consumption, with follow-up to rule out colon cancer

A 69-year-old man was admitted to Hanawa Kousei Hospital with acute hepatitis attributed to alcohol consumption. His condition improved with conservative treatment. Computed tomography (CT) showed localized thickening of the colonic wall at the splenic flexure;carcinoembryonic antigen level was slightly elevated to 9.7 ng/mL. Colonoscopy (CS) showed an ulcerative lesion in the colonic splenic flexure. Ischemic colitis (IC) and type 4 colon cancer were suspected, but biopsy was not confirmatory. Malignancy could not be ruled out by contrast-enhanced CT;repeat CS showed circumferential stenosis of the colonic splenic flexure. Ischemic colitis was suspected based on changes between the first and second CS. Biopsy histopathology led us to diagnose stricture-type IC. Constipation, but not intestinal obstruction, occurred. Conservative treatment improved the stenosis. Excessive alcohol consumption may lead to IC;imaging studies may be useful to distinguish IC from colon cancer. Since most cases of ischemic colitis can be improved with conservative treatment, patients with stricture-type ischemic colitis may also be treated without surgery early on, with follow-up that includes careful, periodic imaging.

Older patients are significantly more likely to have colon ischaemia-associated conditions that are chronic and complex

BACKGROUND

Colon ischaemia is a common disease which has been associated with various medications and comorbidities.

AIM

To test the hypothesis that there are differences in the frequencies of these associations in older compared with younger patients.

METHODS

A retrospective cohort study was performed of patients hospitalized with colon ischaemia at two major medical centres from 2005-2017. Clinical, colonoscopic and pathologic criteria were used to identify patients admitted with colon ischaemia; patients with other types of colitis were excluded. Demographic and medical data were extracted. Two cohorts were created: patients aged 18-64 years and patients > 65 years. These were compared using SAS 14.3.

RESULTS

A total of 788 patients were included, of which 271 (34.4%) were of ages 18-64 years, and 517 (66.6%) were 65 years old or older. In the older cohort, constipation-inducing medications (83.8% vs 64.1%; P = <0.0001), diuretics (38.1% vs 25.1%; P = <0.001) and nonsteroidal anti-inflammatory drugs (58% vs 41.5%; P = <0.0001) were more common than in the younger cohort. Antipsychotic medication use was more common in the younger cohort (10.4% vs 5.4%; P = 0.01). There was a higher percentage of younger patients with a history of hypercoaguable state (1.9% vs 0.2%; P = 0.03) and dialysis dependence (22.9% vs 8.7%; P = <0.01), while a higher percentage of patients in the older cohort had a history of chronic obstructive pulmonary disease (12% vs 6.3%; P = 0.01) or atrial fibrillation (18.9% vs 10.3%; P = <0.01).

CONCLUSIONS

Our study shows that older patients are more likely to have colon ischaemia-associated conditions that are chronic and complex, while younger patients are more likely to have acute colon ischaemia-associated conditions.

Review of Drug-induced Injury in Mucosal Biopsies From the Tubular Gastrointestinal Tract

The use of prescription and over-the-counter medications is on the rise in the US population, especially among those aged 65 and over, with over 46% of the population taking at least 1 prescription medication. Given the frequency of medication use, and that the majority of these medications are taken orally, it has become increasingly relevant for pathologist examining endoscopically obtained gastrointestinal tract mucosal biopsies to consider and recognize patterns of mucosal injury associated with various drugs. Reports on injuries associated with certain classes of drugs can be scattered among different sources, making a comprehensive view of various injury patterns and the drugs known to cause them difficult to obtain. Herein, we provide a comprehensive overview of the drugs known to cause mucosal injuries in the tubular gastrointestinal tract organized by the organ involved and the prominent pattern of injury.

Review article: the pharmacological causes of colon ischaemia

BACKGROUND

Colon ischaemia is the most common ischaemic disorder of the gastrointestinal system, can affect any segment of the colon, and may present with a range of symptoms. Diagnosis can be challenging due to symptom overlap with other conditions, varied aetiology, and often rapid and self-resolving course.

AIM

To review comprehensively the literature regarding the pharmacological aetiologies of colonic ischaemia to enhance the understanding of the various mechanisms of disease, presentations, distribution, and outcomes.

METHODS

A PubMed search for "colon ischaemia" and "ischaemic colitis" alone as well as in combination with various known pharmacologic causes was performed. Only the highest quality and relevant literature was included in this review. The quality of the literature for each association was rated by the authors and a consensus was made when discrepancies were encountered. Only associations that were deemed "moderate" or "strong" were included.

RESULTS

The literature considering pharmacologically associated colonic ischaemia is diverse, lacks codification and is characterised by numerous case reports and case series. Constipation-inducing drugs, digoxin, hormonal therapies, illicit drugs, immunomodulators, laxatives, and NSAIDs were strongly associated with colonic ischaemia. Antimicrobials, appetite suppressants, chemotherapies, decongestants, diuretics, ergot alkaloids, serotonin agents, statins, and vasopressor agents were moderately associated.

CONCLUSIONS

Patients presenting with abdominal pain, diarrhoea, or bloody stool need to be evaluated for the possibility of this condition and treated accordingly. Timely diagnosis is necessary to improve patient outcomes. This review aims to increase awareness among clinicians regarding the presentation of pharmacologically induced colonic ischaemia.

Association between lower air pressure and the onset of ischemic colitis: a case-control study

OBJECTIVE

Ischemic colitis (IC) often affects the elderly. Proarteriosclerotic factors, such as hypertension and smoking, and cardiovascular disease are considered major contributors to IC. Although a possible link between certain cerebrocardiovascular disorders and meteorological phenomena has been reported, the relationship between IC onset and weather changes remains uninvestigated. This study examined whether specific meteorological factors were associated with the occurrence of IC.

PATIENTS AND METHODS

We retrospectively enrolled 303 patients who had been diagnosed with IC between January 2003 and June 2010 at Suwa Red Cross Hospital in Nagano Prefecture, Japan. The meteorological data of the days on which IC patients visited the hospital (IC+ days) were compared with those of the days on which IC patients did not (IC- days).

RESULTS

Univariate analysis indicated that IC+ days had significantly lower air pressure (P<0.001), depressed air pressure from the previous day (P<0.001), and fewer daylight hours (P<0.001), as well as higher air temperature (P=0.017), air humidity (P=0.004), wind velocity (P<0.001), and rainfall (P=0.012) compared with IC- days. Multivariate logistic regression analysis of the meteorological data showed that air pressure (odds ratio: 0.935, P<0.001) and change in air pressure from the previous day (odds ratio: 0.934, P<0.001) were related to onset of IC.

CONCLUSION

Lower air pressure and decrease in air pressure from the previous day are possible novel factors associated with the development of IC.

Seasonal variation in occurrence of ischemic colitis: a retrospective study

Objectives We aimed to identify the clinical characteristics of ischemic colitis (IC) and to investigate the occurrence of seasonal variation. Methods From January 2008 to December 2014, 368 had IC as the reason for their admission. A total of 364 patients were enrolled in this study. We investigated patient characteristics and seasonal variations in incidence. Results The mean age (±standard deviation) of patients with IC at diagnosis was 66.8 (±16.9) years. Most patients had abdominal pain (341 cases), hematochezia (337 cases), and diarrhea (199 cases) as their chief complaints. The clinical courses of the disease were classified as transient (294 cases), stricture (17 cases), gangrenous (2 cases), and indeterminate types (51 cases). Although IC tended to occur less frequently in winter, the seasonal difference was not significant. Conclusion There is currently no evidence for seasonal variation in hospital admissions for IC.

Colon Ischemia: An Update for Clinicians

Colon ischemia (CI) is an underrecognized entity associated with high morbidity and mortality. Establishing the diagnosis and initiating appropriate and timely treatment is critical for improving outcomes. Colon ischemia is a disease spectrum that requires a full understanding for recognition and treatment. This review outlines the full spectrum of CI management from initial presentation to medical and surgical treatment.

The role of hypercoagulability in ischemic colitis

OBJECTIVE

The aim of this study is to evaluate the role of thrombophilia-hypercoagulability in ischemic colitis (IC).

MATERIAL AND METHODS

Thrombophilia and fibrinogen were evaluated in 56 cases of IC and 44 controls with known predisposing factors but no evidence of IC. Thrombophilic factors tested were: protein C (PC), protein S, antithrombin (AT), resistance to activated protein C (APCR), lupus anticoagulant (LA), factor V G1691A mutation (FV Leiden), prothrombin G20210A mutation, methylenetetrahydrofolate reductase (MTHFR) gene C677T and A1298C mutations and plasminogen activator inhibitor-1 (PAI-1) gene 5G/4G and 4G/4G polymorphisms.

RESULTS

In IC group were recorded: i) low levels of PC and AT (p = 0.064 and p = 0.022, respectively); ii) low levels of APCR (normal: >2, p = 0.008); iii) high levels of fibrinogen (p = 0.0005); iv) higher number of homozygotes for MTHFR A1298C and C677T mutations (p = 0.061 and p = 0.525 (Pearson chi-square), respectively); v) greater prevalence of 5G/4G and 4G/4G polymorphisms (p = 0.031 (Pearson chi-square)) and vi) higher incidence of LA-positive individuals (p = 0.037, Fischer's exact test). Multivariate analysis was performed to determine the effects of prothrombotic factors in IC. 5G/4G polymorphism of PAI-1 gene (odds ratio (OR) 12.29; 95% confidence interval (CI) 2.26-67.00), APCR (OR 0.089; 95% CI 0.011-0.699) and fibrinogen (OR 1.013; 95% CI 1.003-1.023) were determined as predictors of IC.

CONCLUSIONS

This study suggests that hypercoagulability, hereditary or acquired, plays an essential role in the manifestation of IC.

A population-based study of incidence, risk factors, clinical spectrum, and outcomes of ischemic colitis

BACKGROUND & AIMS

Little is known about progression of ischemic colitis (IC) among unselected patients. We aimed to estimate the incidence, risk factors, and natural history of IC in a population-based cohort in Olmsted County, Minnesota.

METHODS

We performed a retrospective population-based cohort and nested case-control study of IC. Each IC case was matched to 2 controls from the same population on the basis of sex, age, and closest registration number. Conditional logistic regression, the Kaplan-Meier method, and proportional hazards regression were used to assess comorbidities, estimate survival, and identify characteristics associated with survival, respectively.

RESULTS

Four hundred forty-five county residents (median age, 71.6 years; 67% female) were diagnosed with IC from 1976 through 2009 and were matched with 890 controls. The age-adjusted and sex-adjusted incidence rates of IC nearly quadrupled from 6.1 cases/100,000 person-years in 1976-1980 to 22.9/100,000 in 2005-2009. The odds for IC were significantly higher among subjects with atherosclerotic diseases; odds ratios ranged from 2.6 for individuals with coronary disease to 7.9 for individuals with peripheral vascular disease. Of IC cases, 59% survived for 5 years (95% confidence interval, 54%-64%), compared with 90% of controls (95% confidence interval, 88%-92%). Age >40 years, male sex, right-sided colon involvement, concomitant small bowel involvement, and chronic obstructive pulmonary disease were all independently associated with mortality (P < .05).

CONCLUSIONS

The incidence of IC increased during the past 3 decades in a population-based cohort in Minnesota. IC typically presents in older patients with multiple comorbidities and is associated with high in-hospital mortality (11.5%) and rates of surgery (17%).

Incidence of ischemic colitis in treated, commercially insured hypertensive adults: a cohort study of US health claims data

BACKGROUND

Ischemic colitis (IC) incidence rates (IRs) among treated hypertensive patients are poorly understood, and existing literature on the subject is sparse. Antihypertensive drugs may raise the risk of developing IC. Novel antihypertensive agents—such as the direct renin inhibitor aliskiren—have not been assessed for IC risk.

OBJECTIVES

The aims of this study were to evaluate (1) the IRs of probable IC (pIC) in treated hypertensive adults, with a focus on aliskiren-treated patients; (2) the antihypertensive therapies used; and (3) the IRs of pIC in non-hypertensive adults.

METHODS

This study selected hypertensive and non-hypertensive patients (N = 2,356,226 each) from a US health plan claims database. pIC was defined as diagnosis of IC within 3 months after colonoscopy, recto-sigmoidoscopy, or colectomy. IRs were calculated per 100,000 person-years (PYs) with 95% confidence intervals (CIs) and stratified by antihypertensive regimen.

RESULTS

IRs of pIC in hypertensive and non-hypertensive subjects were 18.6 (95% CI 17.6-19.8) and 4.0 (95% CI 3.4-4.7), respectively. The non-hypertensive cohort consisted of younger patients who may have been less prone to developing IC. The overall (i.e., all antihypertensive regimens combined) monotherapy IR per 100,000 PYs was 17.5 (95% CI 16.2-18.8), the overall dual-combination regimen IR per 100,000 PYs was 19.5 (95% CI 17.37-21.83), and the overall triple-plus combination regimen IR per 100,000 PYs was 27.7 (95% CI 22.72-33.38).

CONCLUSION

Study results indicate that the treated hypertensive patients may have a higher risk of pIC compared with non-hypertensive populations. The quantity of antihypertensive agents prescribed may contribute to IC more than treatment duration.

Ischemic colitis: A forgotten entity. Results of a retrospective study in 118 patients

OBJECTIVE

The aim of our study was to document our 6-year experiences in identifying the clinical characteristics, laboratory findings, risk factors and the outcomes of patients with ischemic colitis (IC) in a community hospital setting.

METHODS

The medical records of patients who were diagnosed with IC from 2007 to 2013 in two community hospitals were retrospectively reviewed. Their clinical characteristics, laboratory results, radiological, endoscopic and histological evidence, anatomic location of the lesion, comorbidities, concomitant use of drugs, and so on, were collected.

RESULTS

A total of 118 patients with IC was identified, most were elderly individuals with a female predominance. The most common symptoms were abdominal pain, rectal bleeding and diarrhea. Hypertension, hyperlipidemia, coronary artery disease and diabetes mellitus were the most common comorbidities. Erythema, edema and erosions/ulcerations were the most common endoscopic findings. Left colon was the most affected location of lesion (84.8%), and there was one case of pancolitis. The descending colon was the most common affected segment, while rectum was the least affected segment. Severe IC occurred in 12.7% of the patients. Death within 30 days from the diagnosis of the disease occurred in 4.2%.

CONCLUSIONS

IC is majorly occurred in elderly with a female predominance. Cardiovascular disease and its associated risk factors are the most common comorbidities. Left colon is the most affected location of the disease and the overall mortality rate was 4.2%. Physicians should make every effort to identify these patients, especially those with high risks.

Ischaemic colitis: indications, extent, and results of standardized emergency surgery

BACKGROUND

Acute ischaemic colitis can occur postoperatively, mainly after aortic surgery, or spontaneously. Surgical treatment is debated. Study aim was to describe factors related to ischaemic colitis severity, determine if postoperative and spontaneous ischaemic colitis share similar outcomes, and evaluate results of standardized management.

METHODS

191 consecutive cases of ischaemic colitis observed from 1997 to 2012 were retrospectively analyzed: 119 (62%) after surgery and 72 (38%) spontaneous. Colon resection was performed for endoscopic type 2 colitis with multiple organ failure, and for every type 3. Types 1 and 2 without multiple organ failure were managed nonoperatively.

RESULTS

Seventeen patients (9%) were managed nonoperatively, without mortality. Mortality rate after resection was 48% (84/174), within 9 days (range, 0-152). Multivariate analysis found 2 independent factors associated with postoperative death: age≥75 years and multiple organ failure. The context in which ischaemic colitis occurred was not a risk factor for mortality. Mortality rates were 51% for final type 3 (66% with multiple organ failure, 17% without), 53% for final type 2 with multiple organ failure, and 0% for type 1 or type 2 without multiple organ failure.

CONCLUSION

An aggressive surgical approach in patients with ischaemic colitis seems justified in patients with multiple organ failure and findings of severe form of ischaemia at endoscopy.

A 9-year evaluation of temporal trends in alosetron postmarketing safety under the risk management program

OBJECTIVES

Adverse events (AEs) of ischemic colitis (IC) and complications of constipation (CoC) associated with alosetron are rare and have been adjudicated during the first 5.5 years of the risk management program (RMP); however, changes in incidence rates relative to reductions in AE reports and increases in alosetron prescriptions over the 9-year RMP have not been evaluated. The authors aim to evaluate temporal trends in alosetron postmarketing safety over the 9-year RMP.

METHODS

The alosetron safety database was searched to identify cases of IC, CoC, and related AEs from 20 November 2002 to 31 December 2011. Adjudication of IC and CoC cases were based on US Food and Drug Administration-defined criteria. Incidence rates were calculated using the number of AEs and alosetron prescriptions (expressed as cases/1000 patient-years exposure).

RESULTS

A total of 29 cases were adjudicated as probable/possible IC and 7 cases were adjudicated as CoC. Cumulative adjudicated incidence rate of IC (1.03 cases/1000 patient-years) is low and stable, while that of CoC (0.25 cases/1000 patient-years) is low, declining progressively over time. Decreases in the incidence rates of potential symptoms of IC (abdominal pain with bloody diarrhea/hematochezia) and CoC (constipation) were also observed.

CONCLUSIONS

Over the 9-year RMP period, incidence rates of IC and CoC remain rare. Substantial reductions over time were observed in the incidence of CoC and in symptoms suggestive of IC or CoC, while IC incidence has been stable at approximately 1.0 case/1000 patient-years. Decreases in AEs and serious outcomes associated with IC and CoC since the reintroduction of alosetron are likely attributable to the RMP.

Clinical characteristics of ischemic colitis after surgery for colorectal cancer

PURPOSE

This study was performed to clarify the clinical features of ischemic colitis (IC) after colorectal cancer surgery.

METHODS

This study retrospectively reviewed the medical records of 35 patients with IC. Patients were divided into two groups: those who had undergone colorectal cancer surgery (POIC group, n = 13) and those who had not undergone colorectal cancer surgery (NOIC group, n = 22). Gangrenous colitis was seen in one patient in the POIC group, and transient colitis was seen in the remaining 34 patients.

RESULTS

Among the patients with transient colitis, there were significantly more patients without underlying diseases or promoting factors in the POIC group than in the NOIC group (P = 0.01). Abdominal pain was more frequently reported in the NOIC group than in the POIC group as both the initial symptom (P = 0.02) and throughout the disease course (P = 0.02). Ischemic changes occupying more than half the circumference of the intestinal wall were more frequently found in the NOIC group than in the POIC group (P = 0.03).

CONCLUSIONS

Although transient POIC may occur without any underlying disease, severe symptoms rarely occur. However, if POIC occurs in a patient with severe underlying disease, then the occurrence of severe colitis should be considered.

Retrospective analysis of disease association and outcome in histologically confirmed ischemic colitis

OBJECTIVE

To identify risk factors, clinical features and complications in patients with ischemic colitis (IC).

METHODS

All patients diagnosed with biopsy proven IC within a 2-year period were identified; clinical data were retrospectively collected and subsequently analyzed.

RESULTS

In total, 72 IC patients with a mean age of 68 years were included in this study. Among them, 18 (25.0%) were younger than 65 years with a female predominance. One-third of the patients was found to be without vascular risk factors, and 8 patients met the criteria for irritable bowel syndrome. No history of oral contraceptives or hormonal replacement therapy use could be found among the women diagnosed with IC. Over a mean duration of follow-up of 9.5 months (range 0-65 months), the rate of recurrent disease was 16.7%, while only 2 (2.8%) patients developed extra intestinal vascular sequelae. Statistical analysis identified a history of atrial fibrillation and the use of furosemide to be the only significant predictors of a poor outcome, while coronary artery disease and chronic renal failure predicted recurrence and low platelet count predicted stricture formation.

CONCLUSIONS

Although most patients with IC are elderly and have conventional vascular risk factors, it should also be considered in young patients without vascular risk factors, especially in women, who may have an atypical distribution of the disease. Severe complications and extraintestinal vascular sequelae are rare, however, residual gastrointestinal complaints and recurrent disease are relatively common and there are no reliable predictors of the outcome.

Ischemic colitis: the ABCs of diagnosis and surgical management

Ischemic colitis (IC) is a rare condition. As ischemia is often transient and clinical symptoms are reversible, its exact incidence is unknown. In current clinical practice, two types of IC are described according to the severity: severe IC, with transmural colonic ischemia and/or multi-organ failure (MOF), and mild IC, without MOF and spontaneous favourable evolution in most cases. Two clinical contexts are encountered: spontaneous IC (SIC) and postoperative IC (POIC), mainly after aortic surgery. As there is no specific clinico-biologic symptom of IC, emergent CT-scan and rectosigmoidoscopy are required for diagnosis confirmation, surgical decision and prognosis analysis. IC surgical treatment is not consensual but can be standardized according to organ function and the degree of ischemia: surgical treatment in case of colonic necrosis with deep ischemia and/or MOF; observation for superficial ischemia without organ dysfunction; systematic medical care. Surgery is required in 20% of cases, and consists in extended colectomy without continuity restoration and prophylactic cholecystectomy. Continuity restoration is feasible in one third of survivors, who are exposed to a high risk of severe cardiovascular events.

Red blood cell transfusion use in patients with chronic kidney disease

BACKGROUND

There is limited data available on the use of red blood cell (RBC) transfusions in younger chronic kidney disease patients not on dialysis (CKD-ND), for whom the consequences of developing antibodies to foreign antigens (allosensitization) may be particularly relevant.

METHODS

We used the Ingenix medical claims database, comprising data on ∼40 million commercially insured US individuals, to identify annual (2002-08) cohorts of patients 18-64 years of age with newly diagnosed CKD. We followed each cohort for 1 year to estimate RBC transfusion rates and used Cox proportional hazards regression to identify patient characteristics associated with time to first transfusion.

RESULTS

We identified 120 790 newly diagnosed CKD patients for the years 2002-08; 54% were 50-64 years of age. Overall, the transfusion rate was 2.64/100 person-years (PYs) (95% CI: 2.52-2.77). Rates were higher among those with diagnosed anemia [9.80/100 PYs (95% CI: 9.31-10.3)] and among those who progressed to end-stage renal disease (ESRD) [28.0/100 PYs (95% CI: 23.7-33.0)]. For those progressing to ESRD, transfusion rates more than doubled between 2002 and 2008. Of the factors evaluated, transfusion history and the presence of heart failure and diabetes were most strongly associated with a receipt of a transfusion.

CONCLUSIONS

RBC transfusions are relatively common and on the rise among younger CKD-ND patients who are anemic and progress to ESRD. Efforts to decrease the use of transfusions may be important for potential transplant candidates who progress to ESRD.

Alosetron: an effective treatment for diarrhea-predominant irritable bowel syndrome

Serotonin (5-HT) is one of the key mediators of gut motility, secretion and sensation. Most 5-HT is localized in the gastrointestinal tract. Particularly important for gut function and regulation are the 5-HT(1P), 5-HT(3) and 5-HT(4) receptors. These receptors have been the focus of research evaluating the pathophysiologic mechanisms of irritable bowel syndrome (IBS) as well as targets for the development of novel agents to treat irritable bowel syndrome. Alosetron is one of three 5-HT(3) antagonists currently available. The other two, ondansetron and granisetron, are primarily used in the treatment of chemotherapy-induced nausea and vomiting. Alosetron, which slows gut transit, has been approved for the treatment of severe diarrhea-predominant IBS (IBS-D) in women. This review will examine the common, yet therapeutically challenging, disorder IBS, as well as the role of alosetron in the treatment of IBS-D.

Clinical characteristics of young-onset ischemic colitis

BACKGROUND

Ischemic colitis (IC) typically develops in the elderly, where hypertension, cerebrocardiovascular disease, and past history of abdominal surgery are regarded as risk factors. Although there have been reports of younger patients with IC, its clinical features remain unclear.

AIM

The aim of this study was to clarify the clinical characteristics of IC in young adults.

METHODS

Three hundred fifty-nine patients were diagnosed as having IC at five hospitals across Nagano prefecture, Japan. Clinical data were compared between the young patient group [20-45 years, n = 53 (15%)] and the elderly patient group [>45 years, n = 306 (85%)], as well as with age- and gender-matched healthy individuals (n = 156).

RESULTS

The presence of a smoking habit and hyperuricemia were significantly higher in the young patient group compared with the elderly patient group (42 vs. 19%, P = 0.001 and 8 vs. 1%, P = 0.019, respectively), which was confirmed by multiple logistic regression analysis (P = 0.001, odds ratio 3.239 and P = 0.028, odds ratio 16.907, respectively). Additionally, multiple logistic regression analysis of the young IC patient group and age- and gender-matched healthy individuals demonstrated that these two factors were strongly associated with IC development (P = 0.008, odds ratio 2.49 for smoking habit and P = 0.039, odds ratio 6.37 for hyperuricemia).

CONCLUSIONS

High prevalences of a smoking habit and hyperuricemia are characteristic features of IC in the young adult population.

Targeted therapies for diarrhea-predominant irritable bowel syndrome

Irritable bowel syndrome (IBS) causes gastrointestinal symptoms such as abdominal pain, bloating, and bowel pattern abnormalities, which compromise patients’ daily functioning. Common therapies address one or two IBS symptoms, while others offer wider symptom control, presumably by targeting pathophysiologic mechanisms of IBS. The aim of this targeted literature review was to capture clinical trial reports of agents receiving the highest recommendation (Grade 1) for treatment of IBS from the 2009 American College of Gastroenterology IBS Task Force, with an emphasis on diarrhea-predominant IBS. Literature searches in PubMed captured articles detailing randomized placebo-controlled trials in IBS/diarrhea-predominant IBS for agents receiving Grade I (strong) 2009 American College of Gastroenterology IBS Task Force recommendations: tricyclic antidepressants, nonabsorbable antibiotics, and the 5-HT₃ receptor antagonist alosetron. Studies specific for constipation-predominant IBS were excluded. Tricyclic antidepressants appear to improve global IBS symptoms but have variable effects on abdominal pain and uncertain tolerability; effects on stool consistency, frequency, and urgency were not adequately assessed. Nonabsorbable antibiotics show positive effects on global symptoms, abdominal pain, bloating, and stool consistency but may be most efficacious in patients with altered intestinal microbiota. Alosetron improves global symptoms and abdominal pain and normalizes bowel irregularities, including stool frequency, consistency, and fecal urgency. Both the nonabsorbable antibiotic rifaximin and the 5-HT₃ receptor antagonist alosetron improve quality of life. Targeted therapies provide more complete relief of IBS symptoms than conventional agents. Familiarization with the quantity and quality of evidence of effectiveness can facilitate more individualized treatment plans for patients with this heterogeneous disorder.

Targeted therapies for diarrhea-predominant irritable bowel syndrome

Irritable bowel syndrome (IBS) causes gastrointestinal symptoms such as abdominal pain, bloating, and bowel pattern abnormalities, which compromise patients' daily functioning. Common therapies address one or two IBS symptoms, while others offer wider symptom control, presumably by targeting pathophysiologic mechanisms of IBS. The aim of this targeted literature review was to capture clinical trial reports of agents receiving the highest recommendation (Grade 1) for treatment of IBS from the 2009 American College of Gastroenterology IBS Task Force, with an emphasis on diarrhea-predominant IBS. Literature searches in PubMed captured articles detailing randomized placebo-controlled trials in IBS/diarrhea-predominant IBS for agents receiving Grade I (strong) 2009 American College of Gastroenterology IBS Task Force recommendations: tricyclic antidepressants, nonabsorbable antibiotics, and the 5-HT(3) receptor antagonist alosetron. Studies specific for constipation-predominant IBS were excluded. Tricyclic antidepressants appear to improve global IBS symptoms but have variable effects on abdominal pain and uncertain tolerability; effects on stool consistency, frequency, and urgency were not adequately assessed. Nonabsorbable antibiotics show positive effects on global symptoms, abdominal pain, bloating, and stool consistency but may be most efficacious in patients with altered intestinal microbiota. Alosetron improves global symptoms and abdominal pain and normalizes bowel irregularities, including stool frequency, consistency, and fecal urgency. Both the nonabsorbable antibiotic rifaximin and the 5-HT(3) receptor antagonist alosetron improve quality of life. Targeted therapies provide more complete relief of IBS symptoms than conventional agents. Familiarization with the quantity and quality of evidence of effectiveness can facilitate more individualized treatment plans for patients with this heterogeneous disorder.

The risk of ischaemic colitis in irritable bowel syndrome patients treated with serotonergic therapies

Ischaemic colitis (IC) is the most common form of ischaemic injury to the gastrointestinal (GI) tract. IC typically presents with the sudden onset of lower abdominal pain, cramping and rectal bleeding, and is usually self-limited with low morbidity, although it may cause gangrenous or fulminant colitis, especially when the right colon is involved. Multiple medical conditions, as well as several pharmacological agents, are associated with IC, including irritable bowel syndrome (IBS) and drugs used for its treatment that act on gut serotonin 5-HT receptors. These include the selective 5-HT(3) receptor antagonist alosetron, currently approved for the treatment of severe diarrhoea-predominant IBS in women who fail to respond to conventional treatment, and cilansetron, another 5-HT(3) receptor antagonist that is no longer in clinical development. In addition, the 5-HT(4) receptor partial agonist tegaserod, which was approved for the treatment of constipation-predominant IBS in women, was associated with IC in the postmarketing setting, as was renzapride, a 5-HT(4) agonist/5-HT(3) antagonist. Although several hypotheses have been proposed, the pathophysiological basis for development of IC with 5-HT(3) receptor antagonists or 5-HT(4) receptor agonists remains unknown. Of interest, several population-based studies demonstrated that a diagnosis of IBS (independent of serotonergic therapies) increases the risk of developing IC 2- to 4-fold. As a result, IBS patients with the acute onset of abdominal pain, tenderness, diarrhoea or lower intestinal bleeding, especially those with predisposing conditions or medications, should be evaluated promptly for IC. The management of IC remains supportive; most cases of non-gangrenous IC, as seen in the alosetron and tegaserod databases, have been transient and have resolved spontaneously without complications or death. Despite the small number of deaths associated with alosetron in patients with complications of constipation and because of the ongoing requirement to prescribe alosetron under a risk management plan, misconceptions persist regarding the definition, incidence, severity and outcome of IC in clinical trials and the postmarketing setting. In this article, the frequency and clinical characteristics of IC associated with the use of alosetron and other serotonergic agents are examined, evidence of an association between IC and IBS is reviewed, and a scoring system to aid in the diagnosis of IC in any clinical situation is proposed.

Systematic review on the treatment of ischaemic colitis

AIM

Ischaemic colitis is uncommon. Aetiological factors include abdominal aortic surgery, drugs (especially inotropics) or rheumatoid diseases, such as Takayasu's or Buerger's diseases. However, there is often no triggering factor, and it may be part of multifactorial cardiac, respiratory, renal or metabolic failure.

METHOD

A systematic review of the current literature on the management of ischaemic colitis was carried out.

RESULTS

Ten retrospective trials (841 patients) were included. No randomized controlled or prospective trial of the management of ischaemic colitis was found.

CONCLUSION

There is very little evidence base for the management of this condition.

Risk factors for intestinal ischaemia among patients registered in a UK primary care database: a nested case-control study

BACKGROUND

Intestinal ischaemia, including ischaemic colitis and acute mesenteric ischaemia, causes significant morbidity and mortality. Few population-based studies have estimated incidence and potential risk factors for this disease.

AIMS

To estimate the incidence of intestinal ischaemia and identify the associated risk factors in cohorts: (i) patients with irritable bowel syndrome and/or chronic constipation (IBS/CC/both), (ii) individuals free of these conditions.

METHODS

Population-based case-control analysis nested in a cohort of patients with first ever recorded diagnosis of IBS/CC/both and a cohort free of these conditions from general population using the General Practice Research Database.

RESULTS

Of 78 cases of intestinal ischaemia, 71 were from general population, seven from the IBS/CC/both cohort. Incidence rate of intestinal ischaemia in IBS/CC/both patients vs. general population was 4.49:1.09 per 100,000 person-years; age- and gender-adjusted incidence rate ratio (95% CI) was 2.7 (1.2-5.9). Inflammatory bowel disease and heart failure showed an association with ischaemic colitis [OR (95% CI): 4.2 (0.5-38.4) and 5.6 (2.2-14.1)], but none with acute mesenteric ischaemia. Diabetes and prior cardiovascular surgery were associated with higher risk of acute mesenteric ischaemia, but showed no association with ischaemic colitis.

CONCLUSIONS

Results suggest that different risk factors are associated with acute mesenteric ischaemia and ischaemic colitis. However, due to small number of patients, associations should be carefully interpreted.

Clinical features of ischemic colitis

Ischemic colitis (IC) is the most common form of ischemic injury of the gastrointestinal tract and occurs more frequently in the elderly. It presents either as an occlusive or a non-occlusive form of intestinal ischaemia. The clinical presentation of IC is variable and non-specific. Colonoscopy is the most common diagnostic method and the golden standard for confirmation of IC. Therapy and outcome depend on the severity and complications of the disease. Most cases of the non-gangrenous form show a favorable prognosis after conservative therapy, while high mortality and urgent operative intervention are the hallmarks of gangrenous IC.

Colon ischemia: recent insights and advances

Ischemic colitis is the most common manifestation of ischemic injury to the gastrointestinal tract, and the variety of defined causes is increasing. Local hypoperfusion and reperfusion injury are both thought to contribute to the disease process, which manifests with a wide spectrum of injury including reversible colopathy (subepithelial hemorrhage and edema), transient colitis, chronic colitis, stricture, gangrene, and fulminant universal colitis. The distribution is typically segmental. Older studies showed that any portion of the colon can be involved; recently, it was established that the site of involvement and prognosis can be correlated. In particular, isolated involvement of the right side of the colon was shown to have a different presentation and worse outcome than ischemic colitis involving other segments. Diagnosis is usually made clinically and supported by radiologic imaging and colonoscopic evaluation. Most patients respond to conservative supportive therapy, although some with severe disease require surgical intervention.

Risk factors associated with the development of ischemic colitis

AIM

To ascertain the role of cardiovascular risk factors, cardiovascular diseases, standard treatments and other diseases in the development of ischemic colitis (IC).

METHODS

A retrospective, case-control study was designed, using matched data and covering 161 incident cases of IC who required admission to our hospital from 1998 through 2003. IC was diagnosed on the basis of endoscopic findings and diagnostic or compatible histology. Controls were randomly chosen from a cohort of patients who were admitted in the same period and required a colonoscopy, excluding those with diagnosis of colitis. Cases were matched with controls (ratio 1:2), by age and sex. A conditional logistic regression was performed.

RESULTS

A total of 483 patients (161 cases, 322 controls) were included; mean age 75.67 ± 10.03 years, 55.9% women. The principal indications for colonoscopy in the control group were lower gastrointestinal hemorrhage (35.4%), anemia (33.9%), abdominal pain (19.9%) and diarrhea (9.6%). The endoscopic findings in this group were hemorrhoids (25.5%), diverticular disease (30.4%), polyps (19.9%) and colorectal cancer (10.2%). The following variables were associated with IC in the univariate analysis: arterial hypertension (P = 0.033); dyslipidemia (P < 0.001); diabetes mellitus (P = 0.025); peripheral arterial disease (P = 0.004); heart failure (P = 0.026); treatment with hypotensive drugs (P = 0.023); angiotensin-converting enzyme inhibitors; (P = 0.018); calcium channel antagonists (P = 0.028); and acetylsalicylic acid (ASA) (P < 0.001). Finally, the following variables were independently associated with the development of IC: diabetes mellitus [odds ratio (OR) 1.76, 95% confidence interval (CI): 1.001-3.077, P = 0.046]; dyslipidemia (OR 2.12, 95% CI: 1.26-3.57, P = 0.004); heart failure (OR 3.17, 95% CI: 1.31-7.68, P = 0.01); peripheral arterial disease (OR 4.1, 95% CI: 1.32-12.72, P = 0.015); treatment with digoxin (digitalis) (OR 0.27, 95% CI: 0.084-0.857, P = 0.026); and ASA (OR 1.97, 95% CI: 1.16-3.36, P = 0.012).

CONCLUSION

The development of an episode of IC was independently associated with diabetes, dyslipidemia, presence of heart failure, peripheral arterial disease and treatment with digoxin or ASA.

Ischemic colitis and complications of constipation associated with the use of alosetron under a risk management plan: clinical characteristics, outcomes, and incidences

OBJECTIVES

Alosetron is a potent, selective 5-HT(3) receptor antagonist prescribed for women with severe diarrhea-predominant irritable bowel syndrome (IBS-D) under a risk management plan (RMP). The RMP was implemented following cases of ischemic colitis (IC) and complications of constipation (CoC) associated with the use of alosetron. The objectives of this study were to characterize IC and CoC clinical features, outcomes, and incidence rates in the new restricted patient population to evaluate the effectiveness of the RMP in the prevention of serious outcomes.

METHODS

Safety data from adverse event reporting from November 2002 through June 2008 were reviewed for probable and possible IC and CoC using the US Food and Drug Administration/sponsor-defined criteria and definitions. Evidence for IC included medical documentation, colonoscopy, and sigmoidoscopy+/-biopsy. Evidence for CoC included medical history and confirmation from health-care professionals.

RESULTS

Within the inclusion dates, 29,072 patients received 203,939 alosetron prescriptions. Although the absolute numbers of IC and CoC cases have declined, the incidence rates for IC and CoC (0.95 and 0.36 cases per 1,000 patient-years, respectively) were similar to rates during the postmarketing cycle before alosetron withdrawal. In patients with severe IBS-D receiving alosetron (n=998) or placebo (n=411) in clinical trials since reintroduction, incidence rates for IC were 4 and 2 cases per 1,000 patients, respectively. Rates for CoC were 2 and 0 cases per 1,000 patients in the alosetron and placebo groups, respectively. No mesenteric ischemia, surgeries, transfusions, or deaths occurred in patients with IC and no cases of CoC were associated with toxic megacolon, perforation, surgeries, transfusions, or deaths. IC and CoC cases were typically of short duration and all improved on prompt withdrawal of alosetron.

CONCLUSIONS

Serious outcomes associated with IC and CoC appear to be mitigated since introduction of alosetron under the RMP.

Alosetron for severe diarrhea-predominant irritable bowel syndrome: safety and efficacy in perspective

Irritable bowel syndrome affects 5-10% of North Americans, with an estimated one-third having a diarrhea-predominant form. Alosetron hydrochloride (Lotronex) is a serotonin receptor type 3 antagonist approved in early 2000 for use in women with diarrhea-predominant irritable bowel syndrome (IBS-D). Initial use was widespread, but infrequent serious adverse events of ischemic colitis and severe constipation-related complications prompted alosetron's voluntary withdrawal from the US market in November 2000. Unprecedented public request prompted its reintroduction in 2002 under a Risk Management Plan, including a more restricted indication and a Prescribing Program for Lotronex. Despite these measures, the use of alosetron has been very limited since its reintroduction. Possible deterrents to its use include concerns over safety and the possible medical-legal implications raised by the Risk Management Plan. It is also possible that changes in the natural history and/or diagnosis of IBS-D have reduced the target population. Given the unique regulatory history of alosetron, these issues continue to engender controversy. This article profiles these concerns and reviews the pharmacology, clinical efficacy and safety, and post-marketing experience with alosetron. Myths and misconceptions related to alosetron use, or lack thereof, are addressed to provide the reader with the evidence needed to make informed treatment decisions for their female patients with severe IBS-D.

Diseases and drugs that increase risk of acute large bowel ischemia

BACKGROUND & AIMS

Information is limited on risk factors for acute large bowel ischemia (ALBI). We investigated diseases and drugs associated with ALBI.

METHODS

We compared patients hospitalized with ALBI and controls through multivariate analysis of prior outpatient/emergency department/inpatient diagnoses and pharmacy dispensing records.

RESULTS

There were 379 cases and 1516 controls (median age, 69 y; range, 25-97 y; 74.4% female). Disorders that were diagnosed in more cases than controls, based on univariate analysis (P < .05), included hypertension, diabetes, chronic obstructive pulmonary disease, atrial fibrillation, congestive heart failure, depression, asthma, coronary artery disease, dementia, rheumatoid arthritis, irritable bowel syndrome, dialysis dependency, diarrhea, and constipation. Drugs dispensed to more cases than controls were antihypertensives, opioids, statins, female hormones, potentially constipating drugs, histamine H(2)-antagonists, immunomodulators, digoxin, clopidogrel/ticlopidine, taxanes/vinca alkaloids, and antibiotics. In all cases, ALBI was associated independently with hypertension (adjusted odds ratio [AOR], 3.21, 95% confidence interval [CI]; 2.28-4.53; P < .0001), chronic obstructive pulmonary disease (AOR, 3.13; 95% CI, 2.06-4.75; P < .0001), diarrhea (AOR, 2.36; 95% CI, 1.13-4.89; P = .0218), atrial fibrillation (AOR, 2.21; 95% CI, 1.34-3.64; P = .0019), congestive heart failure (AOR, 1.94; 95% CI, 1.11-3.39; P = .0205), diabetes (AOR, 1.82; 95% CI, 1.31-2.53; P = .0004), antibiotics (AOR, 3.30; 95% CI, 2.19-4.96; P < .0001), opioids (AOR, 1.96; 95% CI, 1.43-2.67; P < .0001), and potentially constipating drugs (AOR, 1.75; 95% CI, 1.25-2.44; P = .0012). Analysis of only women revealed similar associations except for diarrhea plus rheumatoid arthritis (AOR, 3.27; 95% CI, 1.07-9.96; P = .0370), irritable bowel syndrome (AOR, 2.72; 95% CI, 1.04-7.14; P = .0424), and female hormones (AOR, 1.88; 95% CI, 1.30-2.73; P = .0009).

CONCLUSIONS

Heterogeneous diseases and drugs increase the risk of ALBI, consistent with multifactorial pathogenesis.

Irritable bowel syndrome is more frequent in patients hospitalized for ischaemic colitis: results of a case-control study

It has been suspected that there is an epidemiological link between irritable bowel syndrome (IBS) and ischaemic colitis (IC). We performed a retrospective case-control study to compare the frequency of IBS in patients hospitalized for IC compared with that of patients with peptic ulcer bleeding. Cases were patients with a first episode of IC and controls were patients with a first episode of peptic ulcer bleeding, matched to cases for sex and 10-year age-class. Diagnosis of IBS was based on medical information extracted from hospital medical files and a standard self-questionnaire. The association between IBS and IC was tested using Mc Nemar's paired odds ratio (OR); confidence interval at 95% (CI 95%) was calculated; Mantel-Haenzel's Chi(2) was applied. A total of 113 cases and 113 matched controls were studied. There were 37 males and 76 females and the mean age was 69 +/- 15 years in each group. The prevalence of IBS in cases was 16.9%vs 1.8% in controls. The risk of IBS was 11.05 times higher among cases than in controls (P < 0.001); CI 95%: (2.45-49.74). A total of 87 pairs with complete data were used for OR calculation. The risk of IBS was 7.5 times higher in cases than in controls (P = 0.002); CI 95%: (1.72-32.80). This case-control study shows that IBS is more frequent in IC patients than in controls.