Low-dose aspirin-induced gastrointestinal diseases: past, present, and future

Low-Dose Aspirin Use Does Not Increase Disease Activity in Pregnant Patients with Inflammatory Bowel Disease

BACKGROUND

The adverse effects of non-steroidal anti-inflammatory (NSAID) drugs on the gastrointestinal system are well recognized, but the effect of NSAID use on disease activity patients with inflammatory bowel disease (IBD) remains unresolved. Low-dose aspirin (LDA) is recommended for all pregnant patients with risk factors for developing preeclampsia, including autoimmune conditions. As recognition of risk factors for preeclampsia improves, the preventative use of LDA is likely to increase.

AIMS

To investigate if LDA use for prevention of preeclampsia increases the risk of disease activity in pregnant women with IBD.

METHODS

Single-center retrospective cohort study of pregnant patients with IBD who delivered from 2012 to 2020, comparing those with and without LDA use. Primary outcome was odds of clinical IBD activity in patients in remission at time of conception. Secondary outcomes were rate of elevated inflammatory biomarkers, defined as C-reactive protein > 5 ug/mL or fecal calprotectin > 250 ug/g, and rate of preeclampsia. Univariate analyses tested for associations.

RESULTS

Patients taking LDA were older (p = 0.003) and more likely to have chronic hypertension (p = 0.002), to have undergone in vitro fertilization (p < 0.001), and to be on biologics (p = 0.03). Among patients in remission at conception, there was no difference in clinical disease activity or biomarker elevation during pregnancy based on LDA use (OR 1.27, 95% CI [0.55-2.94], p = 0.6). Rates of preeclampsia were similar between groups.

CONCLUSION

LDA use for preeclampsia prevention did not increase the incidence of disease activity in pregnant patients with IBD.

Inhibition Conversion of Aspirin into Salicylic Acid in Presence of Glycine

Aspirin (AS) is a common drug having anti-pyretic and anti-inflammatory properties which is widely used in diverse medical conditions. The intake of AS may cause adverse effects such as gastrointestinal ulcer, tinnitus and Reye's syndrome. The adverse effects of AS arise due to conversion of AS into salicylic acid (SAL). Glycine (Gly) is a simplest non essential amino acid having anti-oxidative and anti-inflammatory effects. It also reduces the risk of obesity, hypertension, and diabetes mellitus. AS with Gly is well accepted form of the drug for the treatment of rheumatic conditions in comparisons to the bare AS. In the present work using UV-Visible absorption, fluorescence and DFT/ TD-DFT techniques confirmed that in presence of Gly inhibited the conversion of AS into SAL effectively.

Clinical Impact of Proton Pump Inhibitor and Potassium-Competitive Acid Blocker for Predicting the Curability of Endoscopic Resection in Ulcerative Early Gastric Cancer

INTRODUCTION

Endoscopic diagnosis is essential for predicting the curability of early gastric cancer (EGC; R0 resection) before treatment, but the relationship between ulcerative lesions and clinical outcomes remains unclear. We aimed to investigate the effect of proton pump inhibitor (PPI) or potassium-competitive acid blocker (P-CAB) on the morphological changes of ulcerative EGCs and its relevance to the clinical outcomes.

METHODS

Altogether, 143 patients with differentiated ulcerative EGC that were resected by endoscopic submucosal dissection were retrospectively identified and divided into the following two cohorts depending on their PPI/P-CAB administration status: PPI/P-CAB (n = 76) and non-PPI/P-CAB (n = 67) cohorts. Furthermore, in each cohort, the patients were further divided into the improved and unimproved subgroups based on the ulcerative changes.

RESULTS

In the PPI/P-CAB cohort, the deep submucosal invasion and lymphovascular invasion rates were significantly higher in the unimproved subgroup than in the improved subgroup, resulting in a significantly lower R0 resection rate. Contrarily, no significant differences were found between the two subgroups in the non-PPI/P-CAB cohort. The significance of PPI/P-CAB administration was observed only in the ulcerative EGCs with open-type atrophy (R0 resection rate; improved vs. unimproved, 90.9% vs. 48.0%, p = 0.001). When the finding of improved ulcer with PPI/P-CAB administration was used as the indication of endoscopic resection in ulcerative EGCs with open-type atrophy, high sensitivity (78.9%) and accuracy (76.3%) rates for the curability were observed, which were higher than those of conventional endoscopic diagnosis alone (p = 0.021).

CONCLUSION

PPI or P-CAB administration might contribute to the potential selection of ulcerative EGCs, enabling endoscopic curative resection.

Rabeprazole Coadministration Controls Ulcer Recurrence in Patients on Low-dose Aspirin Therapy: A Multicenter Prospective Study

Objective To evaluate the efficacy and safety of rabeprazole coadministration with low-dose aspirin (LDA). Methods From 2015 to 2018, we conducted a large-scale, multicenter, prospective observational study to assess the safety and efficacy of treatment with rabeprazole (5 or 10 mg/day) in combination with LDA. Results The incidence of adverse reactions was 0.73% (11/1,513 patients), with no serious adverse reactions. We found no trend toward increases in the incidence of adverse reactions with increases in treatment duration. The cumulative recurrence rate of ulcers by Week 52 (Kaplan-Meier estimates) was 3.50% (range, 1.56-7.75%). No gastrointestinal bleeding was reported. Conclusion Rabeprazole in combination with LDA appears as safe and effective in real-world situations as in clinical trials.

Cost-Effectiveness of Vonoprazan Compared With Proton Pump Inhibitors in Patients Taking Low-Dose Aspirin for Secondary Prevention of Cardiovascular Events in Japan

BACKGROUND

Low-dose aspirin (LDA) is used to prevent recurrent cardiovascular (CV) events, but is associated with upper gastrointestinal (GI) bleeding; concomitant use of a proton pump inhibitor (PPI) reduces this risk. This study aimed to assess the cost-effectiveness of vonoprazan compared with PPIs (lansoprazole and esomeprazole) in patients taking LDA for secondary prevention of CV events.Methods and Results: A Markov simulation model was developed to predict the number of GI bleeding and acute CV events using 3 strategies (vonoprazan+LDA, esomeprazole+LDA, and lansoprazole+LDA), which were translated into quality-adjusted life-years (QALYs) and costs. Transition probabilities and utilities were derived from the results of published literature, and medical costs were based on the Japanese National Health Insurance fee table and claims databases in 2020. Outcomes were projected over 30 years starting at age 65 years and discounted at 2% annually. Expected costs with esomeprazole 20 mg, lansoprazole 15 mg and vonoprazan 10 mg were JPY 1,225,657, JPY 943,930, and JPY 1,059,510, respectively. The QALY gain for vonoprazan vs. esomeprazole was 0.35, thus vonoprazan was dominant against esomeprazole. The QALY gain for vonoprazan vs. lansoprazole was 0.29 and the incremental cost-effectiveness ratio (ICER) was JPY 398,551, thus, vonoprazan was more cost-effective than lansoprazole.

CONCLUSIONS

Vonoprazan is dominant or cost-effective compared with esomeprazole and lansoprazole in patients taking LDA for secondary prevention of CV events.

Evaluating Risk: Benefit Ratio of Fat-Soluble Vitamin Supplementation to SARS-CoV-2-Infected Autoimmune and Cancer Patients: Do Vitamin–Drug Interactions Exist?

Simple Summary

This review brings attention to a crucial yet under-investigated subject which is vitamin–drug interactions. Fat-soluble vitamins such as vitamins A, D, E, and K have been proven to possess many beneficial effects in the treatment and prevention of COVID-19. Moreover, it has been reported that deficiencies of fat-soluble vitamins have been directly linked to COVID-19 infection-related morbidity and mortality, especially in high-risk populations such as cancer and autoimmune patients. However, many vitamin–drug interactions exist between most of the newly COVID-19 FDA-approved medications and fat-soluble vitamins. Hence, this mandates personalizing the COVID-19 treatment protocols, especially for patients who have any deficiency in any of these vital vitamins. Weighing the risk-to-benefit ratio of supplementing any of these fat-soluble vitamins with COVID-19 medications is considered crucial to maximize the therapeutic benefit and decrease the side effects of these drugs.

Abstract

COVID-19 is a recent pandemic that mandated the scientific society to provide effective evidence-based therapeutic approaches for the prevention and treatment for such a global threat, especially to those patients who hold a higher risk of infection and complications, such as patients with autoimmune diseases and cancer. Recent research has examined the role of various fat-soluble vitamins (vitamins A, D, E, and K) in reducing the severity of COVID-19 infection. Studies showed that deficiency in fat-soluble vitamins abrogates the immune system, thus rendering individuals more susceptible to COVID-19 infection. Moreover, another line of evidence showed that supplementation of fat-soluble vitamins during the course of infection enhances the viral clearance episode by promoting an adequate immune response. However, more thorough research is needed to define the adequate use of vitamin supplements in cancer and autoimmune patients infected with COVID-19. Moreover, it is crucial to highlight the vitamin–drug interactions of the COVID-19 therapeutic modalities and fat-soluble vitamins. With an emphasis on cancer and autoimmune patients, the current review aims to clarify the role of fat-soluble vitamins in SARS-CoV-2 infection and to estimate the risk-to-benefit ratio of a fat-soluble supplement administered to patients taking FDA-approved COVID-19 medications such as antivirals, anti-inflammatory, receptor blockers, and monoclonal antibodies.

Pre-diagnostic faecal calprotectin levels in patients with colorectal cancer: a retrospective study

BACKGROUND

Faecal calprotectin (FC) is a potential biomarker for colorectal cancer (CRC) screening. There is uncertainty if tumor characteristics are associated with FC levels. We investigated how tumor stage and tumor localization influence the extent of FC levels in patients with CRC in clinical practice.

METHODS

In two cohorts of patients with CRC, we retrospectively analyzed FC tests (CALPRO®) performed within three months prior to diagnosis. One hundred twenty-four patients with CRC were included (mean age 68 years, 44% women).

RESULTS

Ninety-eight patients with CRC (79%) had a FC ≥ 50 µg/g. FC correlated positively with tumor stage (UICC based on WHO TNM classification) (r_s 0.24; p = 0.007) and with CRP levels (r_s 0.31, p = 001), and a negatively with B-haemoglobin (r_s -0.21; p = 0.019). The patients with right-sided CRC had significantly more often a FC ≥ 50 µg/g than patients with left-sided CRC (92% vs 74% p = 0.027). In a binary logistic regression analysis, tumor stage III/IV (adjusted OR 3.47; CI 1.27-9.42) and right-sided tumor localization (adjusted OR 3.80; CI 1.01-14.3) were associated with FC ≥ 50 µg/g. Tumor stage III/IV (adjusted OR 2.30; CI 1.04-5.10) and acetylsalicylic use (adjusted OR 3.54; CI 1.03-12.2) were associated with FC ≥ 100 µg/g. In a cox regression analysis, a FC ≥ 100 µg/g was not associated with survival (Hazard OR 0.61; CI 0.24-1.52).

CONCLUSIONS

Elevated pre-diagnostic FC levels were common in patients with CRC in close proximity to diagnosis. Right-sided localization and tumor stage were significantly associated with a rise in FC levels.

A novel gene associated with small bowel bleeding in patients taking low-dose aspirin

OBJECTIVE

We have previously revealed the clinical factors and genetic polymorphisms associated with gastrointestinal mucosal injury and bleeding, induced by low-dose aspirin (LDA). After performing genome-wide analysis of single nucleotide polymorphisms (SNPs) using the Drug Metabolizing Enzymes and Transporters (DMET) system among drug metabolism and transporter genes, certain SNPs were found to increase the risk for LDA-induced small bowel bleeding. The aim of this study was to identify the SNPs involved in LDA-induced small bowel bleeding.

SUBJECTS AND METHODS

Subjects were patients taking LDA, with small bowel bleeding diagnosed using capsule endoscopy. We investigated the clinical characteristics and the previously identified SNPs, that were examined by the DNA direct sequence method.

RESULTS

56 patients with bleeding and 410 controls taking LDA were enrolled. The risk factors associated with small bowel bleeding included smoking, cerebrovascular diseases, chronic renal failure, non-steroidal anti-inflammatory drug (NSAID) or anticoagulants combination, and two SNPs (CYP4F11 20043G>A (D446N) rs1060463, GSTP1 313A>G rs1695). After propensity score matching, GSTP1 rs1695 was significantly associated with small bowel bleeding.

CONCLUSION

The GSTP1 SNP may be a predictive marker for small bowel bleeding among patients taking LDA.

P2Y12 Inhibitors Exacerbate Low-dose Aspirin-induced Small Bowel Injury in Dual Antiplatelet Therapy

Objective Antithrombotic drugs are being used increasingly frequently to prevent cardiovascular diseases. Few studies have evaluated small bowel mucosal injury induced by dual antiplatelet therapy (DAPT). The aim of the present study was to evaluate small bowel mucosal injury induced by DAPT compared with other antithrombotics using video capsule endoscopy (VCE). Methods The study included chronic users of antithrombotics who underwent VCE for obscure gastrointestinal bleeding between January 2007 and July 2018. We evaluated the instances of small bowel injury classified into erosions and ulcers. Results Overall, 183 patients (114 men and 69 women; mean age, 73.6 years old) were enrolled, and the study groups comprised 49 patients taking low-dose aspirin (LDA) only, 50 taking anticoagulants only, 37 being treated with DAPT, 33 on combined LDA and anticoagulants, and 14 taking P2Y12 inhibitors. Small bowel erosions and ulcers were most frequently observed in the DAPT group, with frequencies of 78.4% and 37.8%, respectively. Exacerbating factors of small bowel ulcers were DAPT [odds ratio (OR) 3.0, 95% confidence interval (CI) 1.2-7.7] and age over 80 years old (OR 2.4, 95% CI 1.1-5.4). Conclusion P2Y12 inhibitors seem to exacerbate LDA-induced small bowel injury. Preventive strategies for small bowel injury induced by LDA, especially DAPT, are urgently required.

Prevention of Peptic Ulcer Associated with Aspirin and Antiplatelet Agent

The Korean guidelines for the Clinical Guidelines for Drug-related Peptic Ulcer were revised under the Korean College of Helicobacter and Upper Gastrointestinal Research in 2020. In these revised guidelines, treatment for Helicobacter pylori infections is recommended in patients with a history of peptic ulcers and are receiving long-term low-dose aspirin therapy to prevent peptic ulcers and complications. The maintenance of anti-ulcer drugs, such as proton pump inhibitors, is also recommended after H. pylori eradication if patients require other antiplatelet agents or anticoagulants. Regardless of H. pylori eradication, when patients with a history of peptic ulcer take long-term low dose aspirin, the concomitant use of a proton pump inhibitor according to the severity of the peptic ulcer is recommended.

Proton pump inhibitor use is associated with elevated faecal calprotectin levels. A cross-sectional study on subjects referred for colonoscopy

OBJECTIVES

Faecal Calprotectin (FC) is a sensitive marker for gut inflammation. However, slightly elevated FC levels are also common in subjects without inflammation. We investigated the association between FC and clinical factors including concomitant use of medical therapy in patients with a normal colonoscopy.

MATERIAL AND METHODS

Out-patients (n = 1263) referred for colonoscopy, performed FC test (CALPRO) the day before the start of bowel preparation. All subjects answered questionnaires that included questions on the present and past health history, concomitant medical treatment and gastrointestinal symptoms (GSRS). A medical record chart review was performed to check for concomitant disease, cause of referral and the result of the colonoscopy including biopsies. Inclusion criteria were a normal colonoscopy. Exclusion criteria were inflammatory bowel disease, colon cancer and high-grade dysplasia.

RESULTS

Five hundred ninety subjects fulfilled the inclusion criteria and completed the study. Thirty-six per cent of the subjects had a FC >50 µg/g. In a logistic regression analysis, age (adjusted OR: 1.051; CI: 1.032-1.071), and the use of proton pump inhibitors (adjusted OR: 3.843; CI: 2.338-6.316), non-steroid anti-inflammatory drugs (adjusted OR: 2.411; CI: 1.162-5.002) and acetylsalicylic acid (adjusted OR: 2.934; CI: 1.085-3.448) were significantly associated with an elevated FC (>50 µg/g).

CONCLUSIONS

More than one-third of the patients with a normal colonoscopy performed in clinical routine had a slightly elevated FC level. Our results emphasise the need for attention to age, the use of proton pump inhibitors, non-steroid anti-inflammatory drugs and acetylsalicylic acid in the interpretation of FC tests in clinical practice.

Detection and monitoring of in vitro formation of salicylic acid from aspirin using fluorescence spectroscopic technique and DFT calculations

Acetylsalicylic acid commonly termed as aspirin (AS) is a well known antipyretic and anti-inflammatory drug which can also be used to reduce death risks due to heart attack. In addition to this, it also exhibits some adverse effect such as gastrointestinal, tinnitus, Reye's syndrome. The side effects of AS such as gastrointestinal ulcer, tinnitus and Reye's syndrome are caused due to conversion of AS into its active metabolite salicylic acid (SAL). Conversion of AS into SAL has been investigated generally at basic pH. Since the pH of Gastrointestinal tract is on average neutral ranging from 6.5-7.4. Therefore in the present research work, in vitro conversion of AS to SAL was detected at neutral pH in both aqueous medium and human blood serum samples by time series fluorescence measurements and DFT study. The SAL obtained from AS at neutral pH was observed to be stable for ~ 6 and ~ 4 days in aqueous medium and blood serum, respectively. The mechanism of conversion of AS into SAL was investigated using the transition state theory employing density functional theory (DFT). On the basis of DFT calculation the in vitro formation of SAL from AS at neutral pH was found to involve two intermediate transition states.

The IL-1B Genetic Polymorphism Is Associated with Aspirin-Induced PepticUlcers in a Korean Ethnic Group

Background/Aims

Single nucleotide polymorphisms (SNPs) are associated with aspirin-induced peptic ulcers. However, SNPs of specific genes vary among races, and data regarding SNPs in the Korean population are scarce. In this study, we aimed to investigate the relationships between SNPs of the COX-1, IL-1β, IL-1RN, and TNF genes and aspirin-induced peptic ulcers, as pilot research in a Korean population.

Methods

Patients who had been taking low-dose aspirin (100 mg) for at least 4 weeks were prospectively enrolled. DNA was extracted from whole blood, and DNA sequencing was subsequently performed.

Results

A total of 48 patients were enrolled (23 peptic ulcer patients vs 25 nonulcer controls). Three exon SNPs (IL-1β -581C/T [rs1143627], IL-1β -1061C/T [rs16944], and IL-1RN -1129 [rs4251961]) and one intron SNP (IL-1β IVS2+242C/T) were significantly different between the two groups. On the multivariate analysis after adjustments for age and sex, the CC/CT genotypes of IL-1β -581C/T, and the CT/TT genotypes of IL-1β -1061C/T were positively associated with aspirin-induced peptic ulcers (odds ratio [OR], 4.6, 95% confidence interval [CI], 1.054 to 20.303, p=0.04; OR, 4.6, 95% CI, 1.054 to 20.303, p=0.04).

Conclusions

The IL-1β -581C/T and IL-1β -1061C/T genotypes may be associated with low-dose aspirin-induced peptic ulcers in a Korean ethnic group.

Soluble Dietary Fiber Can Protect the Gastrointestinal Mucosa Against Nonsteroidal Anti-Inflammatory Drugs in Mice

BACKGROUND

Nonsteroidal anti-inflammatory drug (NSAID)-induced small intestinal damage is a serious problem in patients, but effective therapy is not available at present.

AIMS

The effects of feeding conditions and dietary fiber (DF) on NSAID-induced gastrointestinal lesions were examined in mice.

METHODS

NSAIDs (indomethacin, diclofenac, loxoprofen, aspirin) were administered to male mice in various feeding conditions. Gastrointestinal lesions were examined 24 h after NSAID dosing. Regular diets, dietary-fiber-free diet (FFD), and diets supplemented with various types of DF were given to mice.

RESULTS

NSAIDs produced marked ulcers and perforations selectively in the gastric antrum when they were administered after feeding of regular diet for 2 h after a 22-h fast. When NSAIDs, except for aspirin, were administered in unfasted conditions, they caused marked lesions in the small intestine. When mice were given FFD, antral ulcers and intestinal lesions induced by indomethacin (30 mg/kg, s.c.) markedly decreased, but when cellulose, an insoluble DF, was added to FFD, the lesions appeared again. The addition of pectin, a soluble DF, to regular diet containing 4.1 % crude fiber significantly inhibited the formation of antral ulcers as well as intestinal lesions caused by indomethacin or diclofenac (100 mg/kg, s.c.).

CONCLUSIONS

The results indicated that NSAIDs given after feeding of diet produced ulcers selectively in the gastric antrum. The severity of the gastrointestinal lesions depended on the concentration of soluble or insoluble DF in food. Our results suggest that soluble DF such as pectin may be a safe means for protecting the gastrointestinal mucosa against NSAIDs.

Acetylsalicylic acid-induced changes in the chemical coding of extrinsic sensory neurons supplying the prepyloric area of the porcine stomach

Acetylsalicylic acid is a popular drug that is commonly used to treat fever and inflammation, but which can also negativity affect the mucosal layer of the stomach, although knowledge concerning its influence on gastric innervation is very scarce. Thus, the aim of the present study was to study the influence of prolonged acetylsalicylic acid supplementation on the extrinsic primary sensory neurons supplying the porcine stomach prepyloric region. Fast Blue (FB) was injected into the above-mentioned region of the stomach. Acetylsalicylic acid was then given orally to the experimental gilts from the seventh day after FB injection to the 27th day of the experiment. After euthanasia, the nodose ganglia (NG) and dorsal root ganglia (DRG) were collected. Sections of these ganglia were processed for routine double-labelling immunofluorescence technique for substance P (SP), calcitonine gene related peptide (CGRP), galanin (GAL), neuronal isoform of nitric oxide synthase (nNOS) and vasoactive intestinal polypeptide (VIP). Under physiological conditions within the nodose ganglia, the percentage of the FB-labeled neurons immunoreactive to particular substances ranged between 17.9 ± 2.7% (VIP-like immunoreactive (LI) neurons in the right NG) and 60.4 ± 1.7% (SP-LI cells within the left NG). Acetylsalicylic acid supplementation caused a considerable increase in the expression of all active substances studied within both left and right NG and the percentage of neurons positive to particular substances fluctuated from 47.2 ± 3.6% (GAL-LI neurons in the right NG) to 67.2 ± 2.0% (cells immunoreactive to SP in the left NG). All studied substances were also observed in DRG neurons supplying the prepyloric region of the stomach, but the number of immunoreactive neurons was too small to conduct a statistical analysis. The obtained results show that ASA may influence chemical coding of the sensory neurons supplying the porcine stomach, but the exact mechanisms of this action still remain unknown.

Soluble Dietary Fibers Can Protect the Small Intestinal Mucosa Without Affecting the Anti-inflammatory Effect of Indomethacin in Adjuvant-Induced Arthritis Rats

BACKGROUND/AIM

How to prevent the small intestinal damage induced by NSAIDs is an urgent issue to be resolved. In the present study, we examined the effects of soluble dietary fibers on both anti-inflammatory and ulcerogenic effects of indomethacin in arthritic rats.

METHODS

Male Wistar rats weighing 180-220 g were used. Arthritis was induced by injecting Freund's complete adjuvant (killed M. tuberculosis) into the plantar region of the right hindpaw. The animals were fed a regular powder diet for rats or a diet supplemented with soluble dietary fibers such as pectin or guar gum. Indomethacin was administered once a day for 3 days starting 14 days after the adjuvant injection, when marked arthritis was observed. The volumes of the hindpaw were measured before and after indomethacin treatment to evaluate the effect of indomethacin on edema. The lesions in the small intestine were examined 24 h after the final dosing of indomethacin.

RESULTS

Hindpaw volume was increased about 3 times 14 days after injection of the adjuvant. Indomethacin (3-10 mg/kg, p.o.) decreased hindpaw volume dose-dependently, but caused severe lesions in the small intestine at doses of 6 and 10 mg/kg. The addition of pectin (1-10 %) or guar gum (10 %) to the diet markedly decreased the lesion formation without affecting the anti-edema action of indomethacin. The same effects of pectin were observed when indomethacin was administered subcutaneously.

CONCLUSIONS

It is suggested that soluble dietary fibers can prevent intestinal damage induced by NSAIDs without affecting the anti-inflammatory effect of these agents.

Toxicity reduction of imidazolium-based ionic liquids by the oxygenation of the alkyl substituent

Five different salicylate based ionic liquids were prepared in order to study their toxicity. Aquatic organisms (A. salina) and a human non-tumor cell line (normal fetal lung fibroblasts, MRC-5) were used for that purpose.

Investigation of Gastroduodenal Mucosal Injury in Japanese Asymptomatic Antiplatelet Drug Users

Antiplatelet drugs are widely used for the prevention of cardiovascular disease and cerebral vascular disorders. Although there have been several studies on gastroduodenal mucosal injury with gastrointestinal (GI) symptoms such as GI bleeding, in antiplatelet drug users (including low-dose aspirin (LDA)), there have been few reports on the association between antiplatelet drug use and gastroduodenal mucosal injury in asymptomatic antiplatelet drug users. This study was a cross-sectional study elucidating the association between antiplatelet drug use and gastroduodenal mucosal injury in asymptomatic antiplatelet drug users.Subjects were 186 asymptomatic Japanese antiplatelet drug users who underwent a regular health checkup. Subjects were divided into those with and without gastroduodenal mucosal injury endoscopically, and the association between gastroduodenal mucosal injury and other data in asymptomatic antiplatelet drug users was investigated.The prevalence of males and drinkers were significantly higher in subjects with gastroduodenal mucosal injury than in those without. In addition, the prevalence of proton pump inhibitor (PPI) users was significantly lower in subjects with gastroduodenal mucosal injury than in subjects without gastroduodenal mucosal injury. Logistic regression analysis showed PPI (odds ratios: 0.116; 95% confidence intervals: 0.021-0.638; P < 0.05) was a significant predictor of a decreased prevalence of gastroduodenal mucosal injury and closed-type (C-type) atrophy (3.172; 1.322-7.609; P < 0.01) was a significant predictor of an increased prevalence of severe gastroduodenal mucosal injury in asymptomatic antiplatelet drug users.Gender and lifestyle, such as drinking, may have an impact on risk of gastroduodenal mucosal injury in asymptomatic subjects taking antiplatelet drugs. Although PPI is a significant predictor of a decreased prevalence of gastroduodenal mucosal injury, including in asymptomatic antiplatelet drug users, status of gastric atrophy should also be considered against severe gastroduodenal mucosal injury.

Long-term efficacy and safety of rabeprazole in patients taking low-dose aspirin with a history of peptic ulcers: a phase 2/3, randomized, parallel-group, multicenter, extension clinical trial

A 24-week, double-blind, clinical trial of rabeprazole for the prevention of recurrent peptic ulcers caused by low-dose aspirin (LDA) has been reported, but trials for longer than 24 weeks have not been reported. The aim of this study is to assess the long-term efficacy and safety of rabeprazole for preventing peptic ulcer recurrence on LDA therapy. Eligible patients had a history of peptic ulcers on long-term LDA (81 or 100 mg/day) therapy. Patients with no recurrence of peptic ulcers at the end of the 24-week double-blind phase with rabeprazole (10- or 5-mg once daily) or teprenone (50 mg three times daily) entered the extension phase. Rabeprazole doses were maintained for a maximum of 76 weeks, including the double-blind 24-week period and the extension phase period (long-term rabeprazole 10- and 5-mg groups). Teprenone was randomly switched to rabeprazole 10 or 5 mg for a maximum of 52 weeks in the extension phase (newly-initiated rabeprazole 10- and 5-mg groups). The full analysis set consisted of 151 and 150 subjects in the long-term rabeprazole 10- and 5-mg groups, respectively, and the cumulative recurrence rates of peptic ulcers were 2.2 and 3.7%, respectively. Recurrent peptic ulcers were not observed in the newly-initiated rabeprazole 10- and 5-mg groups. No bleeding ulcers were reported. No clinically significant safety findings, including cardiovascular events, emerged. The use of long-term rabeprazole 10- and 5-mg once daily prevents the recurrence of peptic ulcers in subjects on low-dose aspirin therapy, and both were well-tolerated.

Treatment and prevention of gastrointestinal bleeding in patients receiving antiplatelet therapy

Antiplatelet therapy is the standard of care for the secondary prevention of acute coronary syndrome and ischemic stroke, especially after coronary intervention. However, this therapy is associated with bleeding complications such as gastrointestinal bleeding, which is one of the most common life-threatening complications. Early endoscopy is recommended for most patients with acute upper gastrointestinal bleeding. After successful endoscopic hemostasis, immediate resumption of antiplatelet therapy with proton-pump inhibitors (PPIs) is recommended to prevent further ischemic events. PPI prophylaxis during antiplatelet therapy reduces the risk of upper gastrointestinal bleeding. The potential negative metabolic interaction between PPIs and clopidogrel is still unclear.

Vitamin E-drug interactions: molecular basis and clinical relevance

Vitamin E (α-, β-, γ- and δ-tocopherol and -tocotrienol) is an essential factor in the human diet and regularly taken as a dietary supplement by many people, who act under the assumption that it may be good for their health and can do no harm. With the publication of meta-analyses reporting increased mortality in persons taking vitamin E supplements, the safety of the micronutrient was questioned and interactions with prescription drugs were suggested as one potentially underlying mechanism. Here, we review the evidence in the scientific literature for adverse vitamin E-drug interactions and discuss the potential of each of the eight vitamin E congeners to alter the activity of drugs. In summary, there is no evidence from animal models or randomised controlled human trials to suggest that the intake of tocopherols and tocotrienols at nutritionally relevant doses may cause adverse nutrient-drug interactions. Consumption of high-dose vitamin E supplements ( ≥  300 mg/d), however, may lead to interactions with the drugs aspirin, warfarin, tamoxifen and cyclosporine A that may alter their activities. For the majority of drugs, however, interactions with vitamin E, even at high doses, have not been observed and are thus unlikely.

Comparison of proton pump inhibitor and histamine-2 receptor antagonist in the prevention of recurrent peptic ulcers/erosions in long-term low-dose aspirin users: a retrospective cohort study

Background. Proton pump inhibitor and histamine-2 receptor antagonist can prevent aspirin-related ulcers/erosions but few studies compare the efficacy of these two agents. Aims. We evaluated the efficacy of omeprazole and famotidine in preventing recurrent ulcers/erosions in low-dose aspirin users. Methods. The 24-week clinical outcomes of the patients using low-dose aspirin for cardiovascular protection with a history of ulcers/erosions and cotherapy of omeprazole or famotidine were retrospectively reviewed. The incidence of gastrointestinal symptoms, recurrent ulcers/erosions, erosive esophagitis, gastrointestinal bleeding, and thromboembolic events was analyzed. Results. A total of 104 patients (famotidine group, 49 patients; omeprazole group, 55 patients) were evaluated. Famotidine group had more gastrointestinal symptoms episodes than omeprazole group (46.9% versus 23.6%, P = 0.01). Fifteen famotidine group patients and 5 omeprazole group patients had recurrent ulcers/erosions (30.6% versus 9.1%, P = 0.005). Lanza scale was significantly lower in omeprazole group than in famotidine group (1.2 ± 0.7 versus 1.7 ± 1.1, P = 0.008). Only 1 famotidine group patient had ulcer bleeding. The incidences of erosive esophagitis and thromboembolic events were comparable between both groups. Conclusions. Omeprazole was superior to famotidine with less gastrointestinal symptoms and recurrent ulcers/erosions in patients using 24-week low-dose aspirin. The risk of erosive esophagitis, gastrointestinal bleeding, and thromboembolic events was similar between both groups.

Effect of aspirin cessation before endoscopy in Japanese patients with low-dose-aspirin-associated gastroduodenal mucosal injury

BACKGROUND

The incidence of upper gastrointestinal injury by low-dose aspirin (LDA) has increased.

OBJECTIVE

We aimed to clarify the risk factors and prevention strategies associated with LDA-induced gastroduodenal ulcer in Japanese patients.

METHODS

A retrospective study involving 284 LDA users who underwent oesophagogastroduodenoscopy between January and December 2010 were included. We investigated the patients' clinical characteristics and endoscopic findings.

RESULTS

Of 284 patients, 29 (10.2%) had gastro and/or duodenal ulcers. Male gender, peptic ulcer history, abdominal symptoms, half-dose proton pump inhibitors (PPIs), complete-dose PPIs, and nonsteroidal anti-inflammatory drugs were significantly associated with LDA-induced gastro and/or duodenal ulcers: odds ratio (95% confidence interval) 3.62 (1.06-12.27), 6.60 (1.84-23.62), 3.06 (1.12-8.40), 0.16 (0.03-0.94), 0.07 (0.01-0.61), and 9.68 (1.64-57.18), respectively. PPI significantly reduced gastric ulcers and/or duodenal ulcers (p = 0.03). The modified Lanza score for gastric mucosal lesion in the LDA cessation group was significantly lower than in the LDA noncessation group (0.53 vs. 1.02; p = 0.008).

CONCLUSIONS

Half-dose PPIs as well as complete-dose PPIs were effective for preventing LDA-induced gastric and/or duodenal ulcers. The cessation of LDA before endoscopy may lead to an underestimation of LDA-induced gastric injury.

Diarrhea caused by proton pump inhibitor administration: comparisons among lansoprazole, rabeprazole, and omeprazole

BACKGROUND

The number of patients who require treatment with proton pump inhibitors (PPIs) is increasing in Japan. One of their adverse effects is diarrhea.

OBJECTIVES

We investigated the incidence of diarrhea caused by 3 different PPIs: lansoprazole, rabeprazole, and omeprazole.

METHODS

Patients using PPIs for >1 month were enrolled. Enrolled patients recorded daily stool frequency, stool consistency using the Bristol Stool Scale Form, and impaired quality of life caused by diarrhea for 1 month. Their attending physicians described the types and dosages, and duration of PPI administration, as well as other necessary information.

RESULTS

A total of 255 patients participated. Mean age of the patients was 70.7 years old. During the 1-month observation period, 3.5% of the patients complained of diarrhea. There was no significant difference for the incidence of diarrhea among the 3 types of PPIs. Furthermore, no correlations between diarrhea and length and dosage of PPI administration were found.

CONCLUSIONS

The incidence of diarrhea in patients receiving long-term therapy did not differ among 3 different PPIs. ClinicalTrials.gov identifier: UMIN ID 000005300.

Prolonged acetylsalicylic-acid-supplementation-induced gastritis affects the chemical coding of the stomach innervating vagal efferent neurons in the porcine dorsal motor vagal nucleus (DMX)

The main goal of our research was to study the possible alterations of the chemical coding of the dorsal motor vagal nucleus (DMX) neurons projecting to the porcine stomach prepyloric region following prolonged acetylsalicylic acid supplementation. Fast Blue (FB) was injected into the studied area of the stomach. Since the seventh day following the FB injection, acetylsalicylic acid (ASA) was given orally to the experimental gilts. All animals were euthanized on the 28th day after FB injection. Medulla oblongata sections were then processed for double-labeling immunofluorescence for choline acetyltransferase (ChAT), pituitary adenylate cyclase-activating peptide (PACAP), vasoactive intestinal polypeptide (VIP), nitric oxide synthase (NOS), galanin (GAL), substance P (SP), leu enkephalin (LENK), and cocaine- and amphetamine-regulated transcript (CART). In the control DMX, only PACAP was observed in 30.08 ± 1.97 % of the FB-positive neurons, while VIP, NOS, GAL, SP, LENK, and CART were found exclusively in neuronal processes running between FB-labeled perikarya. In the ASA DMX, PACAP was revealed in 49.53 ± 5.73 % of traced vagal perikarya. Moreover, we found de novo expression of VIP in 40.32 ± 7.84 %, NOS in 25.02 ± 6.08 %, and GAL in 3.37 ± 0.85 % of the FB-labeled neurons. Our results suggest that neuronal PACAP, VIP, NOS, and GAL are mediators of neural response to aspirin-induced stomach inflammatory state.

Role of small intestinal bacterial overgrowth in severe small intestinal damage in chronic non-steroidal anti-inflammatory drug users

OBJECTIVE. Enteric bacteria play a significant role in the pathogenesis of non-steroidal anti-inflammatory drug (NSAID)-induced small intestinal damage. However, the association between small intestinal bacterial overgrowth (SIBO) and NSAID-induced small intestinal damage remains unclear. The aim of the study was to examine the association between SIBO and the presence of NSAID-induced severe small intestinal damage or its symptoms in chronic NSAID users. MATERIALS AND METHODS. Forty-three patients who had been using NSAIDs for over 3 months were enrolled. They were examined by capsule endoscopy and a lactulose hydrogen breath test (LHBT). We defined severe small intestinal damage as the presence of more than four small erosions or large erosions/ulcers. The LHBT result was considered positive if there was an increase in the level of breath hydrogen gas of >20 ppm above baseline. RESULTS. Out of 43 patients, 22 (51%) had severe small intestinal damage. The LHBT was positive in 5 of 21 patients (24%) without severe small intestinal damage and in 13 of 21 patients (59%) with severe small intestinal damage. Multiple logistic regression analysis showed that an LHBT-positive result was significantly associated with increased odds ratio for severe small intestinal damage (OR, 6.54; 95% CI, 1.40-30.50). There was no significant difference in the presence of symptoms between the LHBT-positive and LHBT-negative patients with severe small intestinal damage. CONCLUSION. SIBO might have a role in the development of severe small intestinal damage in chronic NSAID users.

[Antiplatelet therapy with acetylsalicylic acid: approaches to reducing the frequency of gastrointenstinal adverse reactions]

Acetylsalicylic acid (ASA) is highly effective in preventing cardiovascular events, but associated with increased risk for digestive adverse reactions. The paper provides an update on the epidemiology, mechanisms, and risk factors of esophagogastroduodeno- and enteropathies during long-term low-dose ACA therapy. It outlines the key principles of their prevention.

Novel single nucleotide polymorphism markers for low dose aspirin-associated small bowel bleeding

BACKGROUND

Aspirin-induced enteropathy is now increasingly being recognized although the pathogenesis of small intestinal damage induced by aspirin is not well understood and related risk factors have not been established.

AIM

To investigate pharmacogenomic profile of low dose aspirin (LDA)-induced small bowel bleeding.

METHODS

Genome-wide analysis of single nucleotide polymorphisms (SNPs) was performed using the Affymetrix DMET™ Plus Premier Pack. Genotypes of candidate genes associated with small bowel bleeding were determined using TaqMan SNP Genotyping Assay kits and direct sequencing.

RESULTS

In the validation study in overall 37 patients with small bowel bleeding and 400 controls, 4 of 27 identified SNPs: CYP4F11 (rs1060463) GG (p=0.003), CYP2D6 (rs28360521) GG (p=0.02), CYP24A1 (rs4809957) T allele (p=0.04), and GSTP1 (rs1695) G allele (p=0.04) were significantly more frequent in the small bowel bleeding group compared to the controls. After adjustment for significant factors, CYP2D6 (rs28360521) GG (OR 4.11, 95% CI. 1.62 -10.4) was associated with small bowel bleeding.

CONCLUSIONS

CYP4F11 and CYP2D6 SNPs may identify patients at increased risk for aspirin-induced small bowel bleeding.

The role of food for the formation and prevention of gastrointestinal lesions induced by aspirin in cats

BACKGROUND/AIMS

The effects of feeding conditions (fasted or fed) and dietary fiber (DF) in the diet on gastrointestinal (GI) damage induced by aspirin (ASA) were examined in cats.

METHODS

Plain ASA (P-ASA, 20 mg/kg) or one enteric-coated ASA tablet (EC-ASA, containing 100 mg ASA) was administered p.o. once daily for 3 or 7 days just after morning meal, 3 h after the evening meal, or in the morning without a morning meal (fasted). Several types of diet, dry food (DRY, DF: 2.8 %), canned food (CAN, DF: 0.4 %), and diets with added cellulose or pectin were provided twice daily.

RESULTS

P-ASA or EC-ASA administered just after feeding of DRY caused marked lesions in the GI tract, although EC-ASA did not produce any lesions in the stomach. GI damage was markedly decreased when ASA was administered 3 h after the evening meal. The induction of lesions by EC-ASA was markedly decreased in cats that ate CAN, but lesions were induced in cats fed CAN with added cellulose (6 %). The addition of pectin (6 %) to the DRY markedly decreased the induction of lesions by EC-ASA.

CONCLUSIONS

The results indicate that the induction of GI lesions by ASA was highly dependent on the feeding conditions and DF. To minimize the induction of GI damage, it would be better to take ASA 3 h after the evening meal, or after consuming diets that contain low amounts of insoluble DF and high amounts of soluble DF.

Characteristics of the small bowel lesions detected by capsule endoscopy in patients with chronic kidney disease

Obscure gastrointestinal bleeding (OGIB) is one of the common complications in patients with chronic kidney disease (CKD), especially those who are on maintenance hemodialysis (HD). However, little is known about the characteristics of the small-bowel lesions in these patients, or of the factors that could predict the presence of such lesions. Therefore we enrolled a total of 42 CKD patients (including 19 HD patients and 23 non-HD patients), and compared the incidence of the small-bowel lesions among two groups. Furthermore, to identify predictive factors for the presence of small-bowel lesions, we performed multivariate logistic-regression-analyses. The incidence of small-bowel vascular lesions was significantly higher in CKD patients than in age-and-sex matched non-CKD patients (P < 0.001). On the other hand, there was any significant difference of the incidence of small-bowel lesions between HD and non-HD patients. In CKD patients, past history of blood transfusion (OR 5.66; 95% CI 1.10–29.1, P = 0.04) was identified as an independent predictor of the presence of vascular lesions, and history of low-dose aspirin use (OR 6.00; 95% CI 1.13–31.9, P = 0.04) was identified as that of erosive/ulcerated lesions. This indicated that proactive CE examination would be clinically meaningful for these patients.

Factors predicting the presence of small bowel lesions in patients with obscure gastrointestinal bleeding

AIM

To identify the predictive factors for the presence of small bowel lesions in patients with obscure gastrointestinal bleeding (OGIB).

METHODS

A total of 242 patients with OGIB (overt 149: occult 93) were retrospectively included in the present study. Capsule endoscopy (CE) was carried out to investigate the small bowel, and detected lesions were classified according to the P0-P2 system. Only P2 lesions were defined as significant lesions. Univariate and multivariate logistic regression analyses were carried out to define the predictive factors for the presence of small bowel lesions.

RESULTS

In patients with overt OGIB, chronic kidney disease (CKD) ≥stage 4 (odds ratio [OR] 4.03; 95% confidence interval [CI] 1.45-11.1, P = 0.007) was identified as an independent predictor of the presence of vascular lesions, and a history of non-steroidalanti-inflammatory drug (NSAID) use as that of erosive/ulcerated lesions (OR 4.73; 95% CI 1.47-15.2, P = 0.009). However, in patients with occult OGIB, no significant predictors of the presence of vascular lesions were identified, whereas a history of low-dose aspirin (LDA) (OR 3.57; 95% CI 1.21-10.5, P = 0.02) and proton pump inhibitor (PPI) use (OR 3.18; 95% CI 1.02-9.92, P = 0.05) were identified as independent predictors of the presence of erosive/ulcerated lesions.

CONCLUSIONS

Our results indicated that bleeding pattern and clinical characteristics could contribute to predicting the origin of OGIB.

A study of the changes in the cause of peptic ulcer bleeding

AIM: To clarify the frequency of and changes in the cause of peptic ulcer bleeding.

METHODS: This study retrospectively evaluated the out- and inpatients who underwent endoscopy between 2002 to 2008. The subjects were patients presenting with peptic ulcer bleeding. The details of these patients were obtained from their endoscopic reports and medical records.

RESULTS: The rates of Helicobacter pylori (H. pylori) infection were significantly low (P = 0.039), while the proportion of nonsteroidal antiinflammatory drugs (NSAIDs) users and vascular disease significantly increased over the period studied (P = 0.034 and P = 0.04, respectively). However, there was no significant difference in the proportion of low-dose aspirin users (P = 0.832).

CONCLUSION: It’s found that the primary cause of peptic ulcer bleeding changed from H. pylori infection to use of NSAIDs over the 7-year period of study. It seems that the number of low-dose aspirin users has increased with the increase in the proportion of vascular disease. It is necessary to take measures to prevent peptic ulcer bleeding among NSAIDs and low dose aspirin users.

Risk and preventive factors of low-dose aspirin-induced gastroduodenal injuries: a comprehensive review

The risk of peptic ulcer complications, particularly bleeding, is increased in association with the use of low-dose aspirin (LDA). Risk factors for upper gastrointestinal (GI) ulcer or bleeding among LDA users include a history of prior GI events, older age, chronic renal failure, combined antithrombotic therapy and nonsteroidal anti-inflammatory drugs (NSAIDs). Helicobacter pylori and aspirin seem to be independent risk factors for peptic ulcer and bleeding. The studies report conflicting findings about the effect of H. pylori infection on NSAID-related ulcers, and proton-pump inhibitors (PPIs) seem to be superior to eradication only to prevent recurrent ulcer bleeding with LDA. Previous studies indicate that hypoacidity related to corpus atrophy, as well as taking PPIs and co-treatment with angiotensin type 1 receptor blockers (ARBs) and statins seem to reduce peptic ulcer among LDA users. In addition, the interleukin-1β (IL-1β)-511 T allele and angiotensinogen (AGT)-20 CC, which work as the high-producer allele of IL-1β and AGT, are significantly associated with ulcer or ulcer bleeding. The SLCO1B1*1b haplotype, which has the highest transport activity, may diminish the preventive effect of statins or ARBs. The data are still lacking and further prospective studies are needed to identify the specific risk or protective factors for upper GI ulcer and its complications associated with LDA.

Association of SLCO1B1 1b with peptic ulcer amongst Japanese patients taking low-dose aspirin

BACKGROUND

In the recent case-control study, we showed an inverse association between peptic ulcer and angiotensin type 1 receptor (AT1R) blockers (ARBs) or HMG-Co A reductase inhibitors (statins). The aim was to evaluate whether the genotypes of uptake and efflux transporters of ARBs and statins relate to the presence of peptic ulcer and/or ulcer bleeding associated with aspirin use.

METHODS

Patients taking 100mg of enteric-coated aspirin for cardiovascular diseases who also participated in endoscopic surveillance were studied. SLCO1B, ABCC2, ABCG2, and MDR1 genotypes were determined by PCR or PCR-RFLP.

RESULTS

492 patients enrolled including 78 with peptic ulcer. The frequencies of the SLCO1B1 521TT genotype were significantly higher in the ulcer group (p=0.006) compared to the controls. After adjustment for significant factors, the SLCO1B1 1b haplotype was significantly associated with peptic ulcer (OR, 3.64; 95% CI, 1.81-7.29).

CONCLUSIONS

SLCO1B1 1b haplotype may identify patients at increased risk for aspirin-induced peptic ulcer.

Acute upper gastro-intestinal bleeding in morocco: what have changed?

Objective. In the present study, we aimed to investigate epidemiological, clinical, and etiological characteristics of acute upper gastro-intestinal bleeding. Materials and Methods. This retrospective study was conducted between January 2003 and December 2008. It concerned all cases of acute upper gastroduodenal bleeding benefited from an urgent gastro-intestinal endoscopy in our department in Morocco. Characteristics of patients were evaluated in terms of age, gender, medical history, presenting symptoms, results of rectal and clinical examinations, and endoscopy findings. Results. 1389 cases were registered. As 66% of the patients were male, 34% were female. Mean age was 49. 12% of patients had a history of previous hemorrhage, and 26% had a history of NSAID and aspirin use. Endoscopy was performed in 96%. The gastroduodenal ulcer was the main etiology in 38%, followed by gastritis and duodenitis in 32.5%. Conclusion. AUGIB is still a frequent pathology, threatening patients' life. NSAID and aspirin are still the major risk factors. Their impact due to peptic ulcer remains stable in our country.

Combination of low-dose aspirin and thienopyridine exacerbates small bowel injury

OBJECTIVE

Antithrombotics is increasingly being used for cardiovascular prevention. In more recent studies, small bowel injury and enteropathy associated with low-dose aspirin are increasingly being recognized. Aim of this study was to evaluate small bowel injury using video capsule endoscopy (VCE) in obscure gastrointestinal bleeding (OGIB) patients taking low-dose aspirin including other antithrombotics.

MATERIAL AND METHODS

This is a retrospective review of chronic users of antithrombotics who underwent VCE for suspected small bowel bleeding. Small bowel mucosal injury was evaluated using VCE findings.

RESULTS

Fifty-four OGIB patients (36 men and 18 women, mean age 72.4 years) underwent VCE from January 2007 to May 2009. Twenty-two patients were taking 100 mg of enteric-coated aspirin (aspirin group), 8 taking thienopyridine, (ticlopidine or clopidogrel, thienopyridine group), 13 taking aspirin combined with thienopyridine (combined group), and 11 taking warfarin (warfarin group). The mucosal injury, especially ulcers were most frequently detected in the combined group (46.2%, p = 0.01) among the four groups. The median number of redness lesions in the combined group was the highest among the four groups and was significantly higher than that in the warfarin group. The lesions of redness or small erosions in the aspirin and the combined groups tended to exist in the proximal part of small bowel.

CONCLUSIONS

Combination of low-dose aspirin therapy and thienopyridine may exacerbate small bowel injury, and the preventive strategies should be established.

Renin-angiotensin system associated with risk of upper GI mucosal injury induced by low dose aspirin: renin angiotensin system genes' polymorphism

BACKGROUND

We have previously shown that co-treatment of angiotensin type 1 receptor (AT1R) blocker (ARB) or angiotensin converting enzyme (ACE) inhibitor seem to reduce peptic ulcer among patients taking low dose aspirin. It is reported that a series of renin-angiotensin system (RAS) gene polymorphisms significantly influence the rate of the gene transcription.

AIM

The aim of this study was to examine the genotypes of RAS genes related to the risk of peptic ulcer and ulcer bleeding among patients taking low dose aspirin.

METHODS

Patients taking 100 mg of aspirin who were planning to undergo endoscopy for surveillance or who had history of recent upper GI ulcer bleeding were included. ACE (Ins/Del), angiotensinogen (AGT; G-217A, A-20C, A-6G, T174 M, M235T), and AT1R (T-713G, C-521T, A1166C) genotypes were determined by PCR or PCR-RFLP.

RESULTS

Four hundred twenty-five patients were enrolled including 68 patients with peptic ulcer and 20 patients with ulcer bleeding. Co-treatment of ARB was significantly associated with peptic ulcer and ulcer bleeding. AGT-20 CC (adjusted OR 4.94, 95% CI 1.21-20.2) was significantly associated with ulcer bleeding. The CC genotype of AT1R-521 was significantly associated with peptic ulcer only in the subgroup taking neither ACE inhibitor nor ARB.

CONCLUSIONS

Co-treatment of ARB reduces peptic ulcer and bleeding among patients taking low dose aspirin. RAS may play an important role in the development of upper GI mucosal injury induced by low dose aspirin.

Risk factors for peptic ulcer bleeding

Bleeding is the most common complication of peptic ulcer. Recent studies have suggested that male sex, blood type O, smoking, ulcer size and location, use of nonsteroidal anti-inflammatory drugs, and meteorological factors were risk factors for peptic ulcer bleeding, while age, Helicobacter pylori infection, psychological-social factors, and economic and educational levels were controversial risk factors for peptic ulcer bleeding.

Risk management of risk management: Combining proton pump inhibitors with low-dose aspirin

Low-dose aspirin is widely used in the primary and secondary prevention of cardiovascular events, but is associated with a range of upper gastrointestinal side effects. In this review, we summarize the rationale for low-dose aspirin therapy, quantify the risk for upper gastrointestinal side effects, identify the risk factors involved, and provide an overview of preventive strategies, thereby focusing on the rationale and clinical utility of combining proton-pump inhibitors with low-dose aspirin.

Aspirin-induced peptic ulcer and genetic polymorphisms

There are a few studies of the association between genetic polymorphisms and the risks of acetylsalicylic acid (aspirin)-induced ulcer or its complications. Two single nucleotide polymorphisms (SNP) of cyclooxygenase-1 (COX-1), A-842G and C50T, exhibited increased sensitivity to aspirin and had lower prostaglandin synthesis capacity, lacking statistical significance in the association with bleeding peptic ulcer. A recent Japanese study indicated that the number of COX-1-1676T alleles was a significant risk factor for peptic ulcer in users of non-steroidal anti-inflammatory drugs (NSAIDs). There are some genetic polymorphisms for aspirin resistance, such as platelet membrane glycoproteins, thromboxane A2 (TXA2) receptor, platelet activating factor acetylhydrolase and coagulation factor XIII; however, data on the frequency of gastrointestinal (GI) events in these variants are lacking. Carrying the CYP2C9 variants is reported a significantly increased risk of non-aspirin NSAID-related GI bleeding. The polymorphisms of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) have been associated with development of peptic ulcer or gastric cancer. In a recent investigation, carriage of the IL-1beta-511 T allele was significantly associated with peptic ulcer among low-dose aspirin users. Hypoacidity in corpus gastritis related to polymorphisms of pro-inflammatory cytokines seems to reduce NSAIDs or aspirin-related injury. Data on which polymorphisms are significant risk factors for GI events in aspirin users are still lacking and further large-scale clinical studies are required.

New method of inducing intestinal lesions in rats by intraduodenal administration of aspirin

BACKGROUND AND AIMS

Enteroscopic observation has clearly demonstrated that non-steroidal anti-inflammatory drugs/low-dose aspirin (usually enteric-coated) induces hemorrhagic lesions, including ulcers and bleeding, in the small intestine of patients at a high incidence. Such intestinal lesions induced by NSAIDs have been confirmed in animal experiments. With aspirin, however, it has long been believed that it is difficult to induce any damage in the intestinal mucosa of laboratory animals. Therefore, we established a new method of inducing intestinal hemorrhagic lesions in rats by injecting aspirin into the proximal duodenum.

METHODS

Under ether anesthesia, aspirin (50-200 mg/body), suspended in 2% methylcellulose (with or without 0.1 N HCl), was injected into the proximal duodenum of normally fed or 20-h non-fed rats (male Sprague-Dawley, 9 weeks old). At 1 h after treatment, the animals were killed with ether and the entire small intestine was removed for histological examination. In some experiments, 1% Evans blue was injected (i.v.) into the rats 1 h after aspirin treatment to visualize the lesions. An image analyzer determined the total area of the intestinal lesions. Oral proton pump inhibitors and histamine H(2)-receptor blockers were given 1 h before aspirin injection. 16,16-dimethyl prostaglandin E(2) (dmPGE(2)) was given s.c. 30 min before aspirin injection.

RESULTS

Aspirin alone clearly induced severe lesions (including bleeding and ulcers) mainly in the jejunum at 100% incidence. Total score of lesions per rat obtained by histological examination was similar to the damaged area quantified with the dye method. Dose-related induction of lesions by aspirin was confirmed both by the histological and dye methods. The irritable effect of aspirin suspended in 0.1 N HCl solution was the same as that of aspirin alone; 0.1 N HCl alone induced only minor lesions in the intestine. Both proton pump inhibitors and histamine H(2)-receptor blockers, at doses that inhibit gastric acid secretion, had no or little effect on aspirin-induced intestinal lesions. Pretreatment with dmPGE(2) (3, 10, 30 microg/kg) showed significant prevention of both aspirin- and HCl/aspirin-induced intestinal lesions.

CONCLUSION

This new aspirin lesion model will be useful for screening defensive drugs against aspirin-induced intestinal lesions and to elucidate the underlying mechanism.

Randomized, double-blind, pilot study of geranylgeranylacetone versus placebo in patients taking low-dose enteric-coated aspirin. Low-dose aspirin-induced small bowel damage

OBJECTIVE

Low-dose enteric-coated aspirin is increasingly being used for prevention of cardiovascular disease. The aim of this study was to evaluate whether geranylgeranylacetone (GGA) could prevent aspirin-induced small bowel injury.

MATERIAL AND METHODS

This was a prospective, randomized, double-blind, pilot study of GGA versus placebo in subjects taking low-dose enteric-coated aspirin. Young healthy volunteers were enrolled and each received 100 mg of enteric-coated aspirin per day plus either GGA (150 mg/day) or matching placebo for 7 days. Video capsule endoscopy of the small bowel and the Gastrointestinal Symptom Rating Scale (GSRS) questionnaire were performed before and after the administration of aspirin.

RESULTS

Twenty volunteers were evaluated. There was no significant difference in the number of lesions in any category between those receiving or not receiving GGA. Large erosions or ulcers were observed in 12 (60%; 95% confidence interval 36%- 80%) aspirin users. Mucosal breaks were most frequently found in the latter half of the proximal small bowel.

CONCLUSIONS

Short-term administration of low-dose enteric-coated aspirin was associated with visible small bowel damage in the majority of users. We could not prove that aspirin-induced small bowel mucosal injury was prevented by GGA.

Noninvasive methods in evaluation of inflammatory bowel disease: where do we stand now? An update

The inflammatory bowel diseases, consisting of Crohn's disease, ulcerative colitis and indeterminate colitis, are distinguished by idiopathic and chronic inflammation of the digestive tract. The distinction between inflammatory bowel diseases and functional bowel disorders, such as irritable bowel syndrome, can be complex because they often present with similar symptoms. Rapid and inexpensive noninvasive tests that are sensitive, specific and simple are needed to prevent patient discomfort, delay in diagnosis, and unnecessary costs. None of the current commercially available serological biomarker tests can be used as a stand-alone diagnostic in clinics. Instead, these are used as an adjunct to endoscopy in diagnosis and prognosis of the disease. Along these lines,, fecal lactoferrin and calprotectin tests seem to be one step further from other tests with larger number of studies, higher sensitivity and specificity and wider availability.

[Guidelines of prevention and treatment for NSAID-related peptic ulcers]

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most commonly used medications in Korea. Gastrointestinal toxicity, including peptic ulcer, is a common adverse effect of NSAIDs. Risk factors for NSAID-related peptic ulcer include a previous history of peptic ulcer, advanced age, high dose, concomitant use of corticosteroids, anticoagulants, other NSAIDs including low-dose aspirin. Preventive measure(s), such as COX-2 inhibitor, proton pump inhibitor or misoprostrol, should be done for patients requiring NSAID therapy who have high-risk factor(s) for peptic ulcer. Low dose aspirin also increases the risk of peptic ulcer, so preventive measure(s) should be done for high-risk patients. The eradication of Helicobacter pylori is recommended for high-risk NSAID-users. Treatment strategies for peptic ulcers in NSAID users are mostly the same for peptic ulcers in NSAID non-users.

In search of pure liquid salt forms of aspirin: ionic liquid approaches with acetylsalicylic acid and salicylic acid

We present an ionic liquid (IL) approach towards a dual functional liquid salt form of aspirin using different pharmaceutically active cations composed of antibacterials, analgesics, local anesthetics, and antiarrhythmic drugs in combination with acetylsalicylic acid or its metabolite salicylic acid and discuss stability of these ILs in comparison to solid salts. Several low-melting or liquid salts of salicylic acid with dual functionality and promising properties were isolated and characterized; however, although such ILs with aspirin could be prepared, they suffer from limited stability and slowly decompose into the corresponding salicylate ILs when exposed to moisture.