Use of single and combined antithrombotic therapy and risk of serious upper gastrointestinal bleeding: population based case-control study

Safety and efficacy of intensive vs. guideline antiplatelet therapy in high-risk patients with recent ischemic stroke or transient ischemic attack: rationale and design of the Triple Antiplatelets for Reducing Dependency after Ischaemic Stroke (TARDIS) trial (ISRCTN47823388)

RATIONALE

The risk of recurrence following a stroke or transient ischemic attack is high, especially immediately after the event.

HYPOTHESIS

Because two antiplatelet agents are superior to one in patients with non-cardioembolic events, more intensive treatment might be even more effective.

SAMPLE SIZE ESTIMATES

The sample size of 4100 patients will allow a shift to less recurrence, and less severe recurrence, to be detected (odds ratio 0·68) with 90% power at 5% significance.

METHODS AND DESIGN

Triple Antiplatelets for Reducing Dependency after Ischaemic Stroke (ISRCTN47823388) is comparing the safety and efficacy of intensive (combined aspirin, clopidogrel, and dipyridamole) vs. guideline antiplatelet therapy, both given for one-month. This international collaborative parallel-group prospective randomized open-label blinded-end-point phase III trial plans to recruit 4100 patients with acute ischemic stroke or transient ischemic attack. Randomization and data collection are performed over a secure Internet site with real-time data validation and concealment of allocation. Outcomes, serious adverse events, and neuroimaging are adjudicated centrally with blinding to treatment allocation.

STUDY OUTCOME

The primary outcome is stroke recurrence and its severity ('ordinal recurrence' based on modified Rankin Scale) at 90 days, with masked assessment centrally by telephone. Secondary outcomes include vascular events, functional measures (disability, mood, cognition, quality of life), and safety (bleeding, death, serious adverse events).

DISCUSSION

The trial has recruited more than 50% of its target sample size (latest number: 2399) and is running in 104 sites in 4 countries. One-third of patients presented with a transient ischemic attack.

Recent clinical management of antithrombotic agents for gastrointestinal endoscopy after revision of guidelines in Japan

In 2012, the Japan Gastroenterological Endoscopy Society (JGES) revised guidelines for the management of gastrointestinal endoscopy for patients using antithrombotic agents. The conventional guidelines emphasized reducing the bleeding risk that accompanies gastrointestinal endoscopy, but the present guidelines prioritize reduction of thromboembolism risk during discontinuation of antithrombotic agents, which is consistent with Western guidelines. When the advantages outweigh the disadvantages, the guidelines permit endoscopic biopsy and high-bleeding-risk procedures without discontinuation of selected antithrombotic agents. These guidelines created a paradigm shift that has slowly, but surely, changed clinical daily practice in Japan. As a result, endoscopic biopsy without discontinuation of antithrombotic agents has been widely accepted, although solid evidence for its support is still lacking. Additionally, feasibility of high-bleeding-risk procedures without discontinuation of selected antithrombotic agents is also controversial because evidence newly acquired after publication of the present guidelines is low in evidence level. Consequently, clinical studies with a high evidence level, including randomized controlled studies, are mandatory to establish reliable upcoming guidelines. At the same time, under the present guidelines, the accomplishment of such studies in Japan is expected.

The effects of proton pump inhibition on patient-reported severity of dyspepsia when receiving dual anti-platelet therapy with clopidogrel and low-dose aspirin: analysis from the Clopidogrel and the Optimization of Gastrointestinal Events Trial

BACKGROUND

Dual anti-platelet therapy with clopidogrel and low-dose aspirin increases the risk for gastrointestinal clinical events. Omeprazole has been shown to significantly reduce these events without compromising cardiovascular safety in patients treated with dual anti-platelet therapy. Whether or not omeprazole improves patient-reported outcomes is undetermined.

AIM

To assess the impact of prophylactic omeprazole with background dual anti-platelet therapy on patient-reported symptoms of dyspepsia compared to placebo.

METHODS

We analysed results of the Severity of Dyspepsia Assessment questionnaires collected in the Clopidogrel and the Optimization of Gastrointestinal Events Trial.

RESULTS

Patient-reported outcome data from 3759 subjects were available for analysis. At 4 weeks, the mean scores of pain intensity and nonpain symptoms were lower in the omeprazole group (5.61 ± 0.17 vs. 6.40 ± 0.17, P = 0.001, and 10.61 ± 0.07 vs. 11.00 ± 0.07, P < 0.001 respectively). These differences were maintained at 24 weeks (5.91 ± 0.35 vs. 7.10 ± 0.37, P = 0.020 for pain intensity; 10.36 ± 0.12 vs. 10.93 ± 0.13, P = 0.001 for nonpain symptoms). After adjusting for covariates there were no statistically significant differences between the groups in the percent of patients with dyspepsia during follow-up.

CONCLUSIONS

In addition to reducing the risk of gastrointestinal bleeding, statistically significant benefits with prophylactic omeprazole use on both pain and nonpain symptoms were evident at 4 weeks and sustained through 24 weeks. The clinical significance of these overall results is unclear, but greater in patients with pain at baseline.

Optimal duration of dual antiplatelet therapy after drug-eluting stent implantation: a meta-analysis of 3 randomized controlled trials

PURPOSE

The optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is still unclear. We conducted a meta-analysis of randomized trials to assess the optimal duration of DAPT after DES implantation.

METHODS

Articles were identified through a literature search of EMBASE, Pubmed, Europubmed, and the Cochrane Library until November 2013. Data were independently extracted by 2 reviewers. A random effect model was used to calculate the pooled odds ratios (ORs) with 95% confidence intervals (CIs) of the clinical outcomes concerned.

RESULTS

Three randomized controlled trials with zotarolimus- or everolimus-eluting stents and 6679 patients were included. There were no significant differences between short-term DAPT and standard-term DAPT in the comparison of incidences of cardiac death (OR, 0.84; 95% CI, 0.53-1.35; P = 0.48), myocardial infarction (OR, 1.21; 95% CI, 0.83-1.75; P = 0.32), stent thrombosis (OR, 1.30; 95% CI, 0.50-3.39; P = 0.59), and target vessel revascularization (OR, 1.16; 95% CI, 0.89-1.52; P = 0.26). Short-term DAPT did not increase the risk of all-cause death (OR, 0.86; 95% CI, 0.59-1.26; P = 0.44), cerebrovascular accidents (OR, 0.88; 95% CI, 0.421.81; P = 0.72), and major bleeding events (OR, 0.59; 95% CI, 0.30-1.15; P = 0.12).

CONCLUSIONS

The results indicate that short-term DAPT do not increase the risk of cardiac death, myocardial infarction, stent thrombosis, target vessel revascularization, major bleeding, cerebrovascular accidents, and all-cause death at 12 months after implantation of DES compared with current standard-term DAPT. However, only 3 studies with second generation of DES are included in this meta-analysis. Further well-designed studies are still needed.

Oral anticoagulant therapy in atrial fibrillation patients at high stroke and bleeding risk

Atrial fibrillation (AF) is associated with a 5-fold greater risk of ischemic stroke or systemic embolism compared with normal sinus rhythm. Cardioembolic AF-related strokes are often more severe, fatal or associated with greater permanent disability and higher recurrence rates than strokes of other aetiologies. These strokes may be effectively prevented with oral anticoagulant (OAC) therapy, using either vitamin K antagonists (VKAs) or non-vitamin K antagonist OACs (NOACs) such as the direct thrombin inhibitor dabigatran or direct factor Xa inhibitors rivaroxaban, apixaban or edoxaban. Most AF patients have a positive net clinical benefit from OAC, excluding those with AF and no conventional stroke risk factors. Balancing the risks of stroke and bleeding is necessary for optimal use of OAC in clinical practice, and modifiable bleeding risk factors must be addressed. Concerns remain over 'non-changeable' bleeding risk factors such as older age, significant renal or hepatic impairment, prior stroke(s) or prior bleeding event(s) and active malignancies. Such AF patients are often termed 'special' AF populations, due to their 'special' risk profile that includes increased risks of both thromboembolic and bleeding events, and due to fear of bleeding complications these AF patients are often denied OAC. Evidence shows, however, that the absolute benefits of OAC are the greatest in patients at the highest risk, and NOACs may offer even a greater net clinical benefit compared to warfarin particularly in these high risk patients. In this review article, we summarize available data on stroke prevention in AF patients at increased risk of both stroke and bleeding and discuss the use of NOACs for thromboprophylaxis in these 'special' AF populations.

Epidemiology and Risk Factors for Upper Gastrointestinal Bleeding

Although the incidence of nonvariceal upper gastrointestinal bleeding (UGIB) has been decreasing worldwide, nonvariceal UGIB continues to be a significant problem. Even with the advent of advanced endoscopic procedures and potent medications to suppress acid production, UGIB carries significant morbidity and mortality. Some of the most common risk factors for nonvariceal UGIB include Helicobacter pylori infection, nonsteroidal antiinflammatory drugs (NSAIDs), aspirin, selective serotonin reuptake inhibitors, and other antiplatelet and anticoagulant medications. In patients with cardiovascular disease and kidney disease, UGIB tends to be more severe and has greater morbidity. Many of the newer NSAIDs have been removed from the market.

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.

Aspirin Has a Protective Effect Against Adverse Outcomes in Patients with Nonvariceal Upper Gastrointestinal Bleeding

OBJECTIVE

To determine the effect of aspirin and anticoagulants on clinical outcomes and cause of in-hospital death in patients with nonvariceal upper gastrointestinal bleeding (NVUGIB).

METHODS

Patients were identified from a tertiary center database that included all patients with UGIB. Clinical outcomes including (1) in-hospital mortality, (2) severe bleeding, (3) rebleeding, (4) in-hospital complications, and (5) length of hospital stay were examined in patients taking (a) aspirin only, (b) anticoagulants only, and (c) no antithrombotics.

RESULTS

Of 717 patients with NVUGIB, 56 % (402) were taking at least one antithrombotic agent. Seventy-eight (11 %) patients died in hospital, and 310 (43 %) had severe bleeding (BP < 90 mmHg, HR > 120 b/min, Hb < 7 g/dL on presentation, or transfusion of >3 units). On multivariate analysis, being on aspirin was protective against in-hospital mortality [OR 0.26 (0.13-0.53)], rebleeding [OR 0.31 (0.17-0.59)], and predictive of a shorter hospital stay (coefficient = -4.2 days; 95 % CI -8.7, 0.3). Similarly, being on nonaspirin antiplatelets was protective against in-hospital mortality (P = 0.03). However, being on anticoagulants was predictive of in-hospital complications [OR 2.0 (1.20-3.35)] and severe bleeding [OR 1.69 (1.02-2.82)]. Compared to those not taking any antithrombotics, patients who bled on aspirin were less likely to die in hospital of uncontrolled gastrointestinal bleeding (3.6 vs 0 %, P ≤ 0.01) and systemic cancer (4.9 vs 0 %, P ≤ 0.002), but equally likely to die of cardiovascular/thromboembolic disease, sepsis, and multiorgan failure.

CONCLUSION

Patients who present with NVUGIB on aspirin had reduced in-hospital mortality and fewer adverse outcomes, while those on anticoagulants had increased in-hospital complications.

Prospective analysis of risk for bleeding after endoscopic biopsy without cessation of antithrombotics in Japan

BACKGROUND AND AIM

In Japan, after the revision of the gastrointestinal endoscopic guidelines for patients taking antithrombotics, endoscopic biopsies were permitted while continuing antithrombotic treatment. However, the risk of bleeding after the biopsy with or without cessation of antithrombotics has not been fully evaluated because bleeding events are very rare. The aim of this prospective study was to evaluate the risk for bleeding after upper gastrointestinal biopsy without cessation of antithrombotics.

METHODS

Consecutive patients who underwent upper gastrointestinal endoscopic biopsy from December 2011 to March 2014 were enrolled in this study. Antithrombotic medication and its cessation status was checked at enrollment. To confirm bleeding events associated with biopsy, medical examination at the hospital or direct confirmation by telephone was done within 1 month after the biopsy.

RESULTS

Among the 3758 patients who underwent endoscopic biopsies, 394 patients (10.5%) were medicated with antithrombotics, and 286 of them (72.6% of the total antithrombotics users) did not undergo cessation. Bleeding after the biopsy occurred in six cases (0.15%, 95% CI; 0.09%∼0.22%), but there was only one case that had continued taking antithrombotics. The incidence of bleeding after biopsy was not significantly higher in the patients who had continued taking antithrombotics compared with the others (0.35% vs 0.14%, P = 0.38).

CONCLUSION

This prospective study showed that continuation of antithrombotics did not increase the bleeding risk after upper gastrointestinal endoscopic biopsy.

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.

Low-Dose Aspirin and Non-steroidal Anti-inflammatory Drugs Increase the Risk of Bleeding in Patients with Gastroduodenal Ulcer

BACKGROUND

Non-steroidal anti-inflammatory drugs (NSAIDs), low-dose aspirin (LDA), non-aspirin antiplatelet medications (APs), and anticoagulant medications (ACs) increase the risk of gastrointestinal bleeding.

AIM

To examine whether NSAIDs, LDA, APs, and ACs use is associated with bleeding from gastroduodenal ulcers.

METHODS

This was a case-control study of patients with endoscopically verified gastroduodenal ulcer diagnosed at our institution from 2004 to 2011. Among 1,611 patients, we identified those who required endoscopic hemostasis for bleeding ulcers as cases. Age-matched, sex-matched, and Helicobacter pylori status-matched patients who did not require therapeutic interventions served as controls. Use of NSAIDs, LDA, APs, and ACs within 2 weeks prior to the endoscopy was compared between cases and controls, and effects on ulcer bleeding were calculated.

RESULTS

We recruited 341 cases and 668 controls. The site and number of ulcers were not different between groups. Multivariate analyses revealed that LDA and NSAIDs, individually, were associated with the increase in the risk of bleeding (OR 1.80 and 95 % CI 1.18-2.75 for LDA; 1.35 and 1.01-1.80 for NSAIDs). In addition, a combination of LDA and NSAIDs or LDA and APs contributed more profoundly to the bleeding (OR 3.59 and 95 % CI 1.19-10.81 for LDA/NSAIDs; OR 6.70 and 95 % CI 1.83-24.50 for LDA/APs). However, ACs, alone or in combination, were not associated with bleeding ulcers.

CONCLUSIONS

Both LDA and NSAIDs are risk factors for upper GI bleeding in patients with gastroduodenal ulcer, while ACs are unrelated to the increased risk. The risk of bleeding with LDA may increase with simultaneous use of APs.

Antithrombotic drugs, patient characteristics, and gastrointestinal bleeding: Clinical translation and areas of research

Gastrointestinal bleeding (GIB) is a potentially fatal and avoidable medical condition that poses a burden on global health care costs. Current understanding of the roles of platelet activation and thrombin generation/activity in vascular medicine has led to the development of effective antithrombotic treatments. However, in parallel with a sustained coronary and cerebral flow patency, the increasingly intensive treatment with warfarin; direct oral anticoagulant drugs [DOACs], and/or with aspirin ± clopidogrel (or ± prasugrel or ± ticagrelor), has increased the burden of GIBs related to the use of antithrombotic agents. Compelling evidence concerning this issue is accumulating to indicate that: 1) the risk of GIB related to the use of antithrombotic drugs dramatically differs in different clinical settings; and 2) the characteristics of patients (e.g., severity of illness, comorbidities) in whom it is used exert a greater impact on the risk of GIB than the type of antithrombotic agent employed. The latter concept argues for the occurrence of GIB as reflecting the presence of patients at the highest risk for adverse outcomes. The HAS-BLED score identifies subjects at risk of bleeding among those untreated and those treated with warfarin, DOACs and/or low-dose aspirin. Its use within the frame of a severity score (e.g., the CHA2DS2-VASc score in patients with atrial fibrillation) helps balance the benefits and the risks of an antithrombotic treatment and identify those patients in whom the absolute gain (vascular events prevented) outweighs the risk of GIB. Potential implications of the latter information in settings other than atrial fibrillation is thoroughly discussed.

Long-term outcome in patients with obscure gastrointestinal bleeding after capsule endoscopy

OBJECTIVE

This study aimed to identify the risk factors associated with rebleeding and long-term outcomes after capsule endoscopy (CE) for obscure gastrointestinal bleeding (OGIB) in a follow-up study.

METHODS

Data of consecutive patients who underwent CE due to OGIB from June 2002 to January 2012 were retrospectively reviewed. The Cox proportional hazard model was used to evaluate the risk factors associated with rebleeding, while Kaplan-Meier survival curves and the log-rank test were used to analyze cumulative rebleeding rates.

RESULTS

The overall rebleeding rate after CE in patients with OGIB was 28.6% (97/339) during a median follow-up of 48 months (range 12-112 months). Multivariate analysis showed that age ≥60 years (hazard ratio [HR] 2.473, 95% confidence interval [CI] 1.576-3.881, P = 0.000), positive CE findings (HR 3.393, 95% CI 1.931-5.963, P = 0.000), hemoglobin ≤70 g/L before CE (HR 2.010, 95% CI 1.261-3.206, P = 0.003), nonspecific treatments (HR 2.500, 95% CI 1.625-3.848, P = 0.000) and the use of anticoagulants, antiplatelet or non-steroidal anti-inflammatory drugs after CE (HR 2.851, 95% CI 1.433-5.674, P = 0.003) were independent risk factors associated with rebleeding. Univariate analysis showed that chronic hepatitis was independently associated with rebleeding in CE-negative patients (P = 0.021).

CONCLUSIONS

CE has a significant impact on the long-term outcome of patients with OGIB. Further investigation and close follow-up in patients with OGIB and those with negative CE findings are necessary.

Recurrence and mortality among patients hospitalized for acute lower gastrointestinal bleeding

BACKGROUND & AIMS

The long-term recurrence of lower gastrointestinal bleeding (LGIB) and associated mortality have not been studied extensively. We investigated rates of recurrence of LGIB, mortality, and associated risk factors.

METHODS

In a retrospective study, we analyzed data from 342 patients hospitalized for overt LGIB at the National Center for Global Health and Medicine in Japan from December 2004 through June 2013. All patients underwent colonoscopy. We assessed Charlson comorbidity index scores and the use of nonsteroidal anti-inflammatory drugs, low-dose aspirin, other antiplatelet drugs, or warfarin. Rebleeding, the total number of rebleeding episodes, and mortality were measured. The Cox proportional hazards model was used to estimate hazard ratios (HRs).

RESULTS

Rebleeding occurred in 84 patients, at a mean follow-up time of 19 months. The cumulative percentages of patients with rebleeding at 1 and 5 years were 19% and 46%, respectively. During the follow-up period, 29 patients (39%) had secondary rebleeding and 18 patients (62%) had subsequent rebleeding. Multivariate analysis showed age 65 years and older (HR, 1.7; P = .04) and the use of nonsteroidal anti-inflammatory drugs (HR, 2.0; P < .01) and nonaspirin antiplatelet drugs (HR, 1.8; P < .05) as independent risk factors for rebleeding. Dual therapy had a higher risk than single therapy (adjusted HR, 1.8; P < .05). During the mean follow-up period of 28 months, 21 patients died (2 from bleeding). Cumulative mortality rates at 1 and 5 years were 4.2% and 13%, respectively. Mortality was associated significantly with age ≥65 years (P < .05), Charlson comorbidity index score, and warfarin use.

CONCLUSIONS

Based on a retrospective analysis of patients with LGIB, 46% of all patients have rebleeding, and the overall mortality rate is 13% within 5 years after hospitalization. Besides age ≥65 years, use of antithrombotic drugs increases the risk of bleeding recurrence and mortality among patients with LGIB.

Risk of peptic ulcer bleeding associated with Helicobacter pylori infection, nonsteroidal anti-inflammatory drugs, low-dose aspirin, and antihypertensive drugs: a case-control study

BACKGROUND AND AIM

The associations between antithrombotic or antihypertensive drugs and peptic ulcer bleeding (PUB) remain unknown, particularly in Asia, where Helicobacter pylori infection is prevalent. This study aims to evaluate the risks of PUB from antithrombotic drugs, angiotensin II receptor blockers (ARBs), angiotensin-converting enzyme (ACE) inhibitors, calcium channel blockers, α-blockers, and β-blockers.

METHODS

This prospective hospital-based case-control study included 230 patients with endoscopically verified PUB and 920 age and sex-matched controls (1:4) without bleeding on screening endoscopy. Adjusted odds ratios (AOR) for the risk of PUB were determined by conditional logistic regression analysis.

RESULTS

In multivariate analysis, alcohol consumption (AOR, 2.2; P < 0.001), history of peptic ulcer (AOR, 4.8; P < 0.001), H. pylori infection (AOR, 2.1; P < 0.001), comorbidity index (AOR, 1.1; P = 0.089), nonsteroidal anti-inflammatory drugs (NSAIDs) (AOR, 2.0; P = 0.025), and low-dose aspirin (AOR, 2.8; P = 0.003) increased the risk of PUB, whereas H. pylori eradication (AOR, 0.03; P < 0.001), proton pump inhibitors (PPIs) (AOR, 0.1; P < 0.001), and histamine 2-receptor antagonists (H2RA) (AOR, 0.1; P < 0.001) reduced it. No significant interactions were observed between H. pylori infection and NSAIDs use for PUB (P = 0.913). ARBs (P = 0.564), ACE inhibitors (P = 0.213), calcium channel blockers (P = 0.215), α-blockers (P = 0.810), and β-blockers (P = 0.864) were not associated with PUB.

CONCLUSION

We found that alcohol consumption, history of peptic ulcer, H. pylori infection, NSAIDs use, and low-dose aspirin use were independent risk factors for PUB, whereas H. pylori-eradication, PPIs use, and H2RA use reduced its risk. Interactions between H. pylori and NSAIDs use in PUB were not observed. No antihypertensive drug was associated with PUB.

The outcome and role of drugs in patients with unexplained gastrointestinal bleeding

OBJECTIVE

Studies on unexplained gastrointestinal bleeding (GIB) are lacking. We aimed to study the clinical outcomes of patients with unexplained GIB and to determine the incidence of obscure GIB.

MATERIAL AND METHODS

A population-based study on all patients undergoing endoscopy at the National University Hospital of Iceland in 2010. Indications, results of endoscopies and drug history were prospectively registered with a follow-up of 3 years. A national pharmaceutical database containing prescription data was utilized. Patients were categorized into unexplained overt and occult GIB and obscure GIB. Patients undergoing endoscopy and without GIB acted as controls.

RESULTS

Of 2471 patients undergoing endoscopy, 11% had unexplained GIB. Of those, 46% had unexplained overt GIB, 44% had unexplained occult GIB and 11% had obscure GIB. Multivariate analysis showed that patients with unexplained GIB and unexplained overt GIB had greater odds of NSAID use than controls, OR 1.8 (CI 1.03-3.03) and OR 2.0 (CI 1.01-3.77), respectively. Warfarin was strongly associated with all bleeder groups, OR 4-4.8. The incidence of obscure GIB was 10/100,000 inhabitants annually. Two (0.8%) patients were diagnosed with colon cancer 16 and 30 months after the index colonoscopy. Of patients with unexplained overt, unexplained occult GIB and controls, 5%, 6% and 3.5% (NS) had another overt bleeding episode, during the study period.

CONCLUSIONS

NSAIDs and warfarin seem to play an important role in unexplained GIB. The incidence of obscure GIB is low and missed cancers are very rare. The probability of a repeat bleeding episode is similar to that of controls.

Characteristics of patients with non-variceal upper gastrointestinal bleeding taking antithrombotic agents

BACKGROUND AND AIM

The present study aimed to clarify the features and management of non-variceal upper gastrointestinal bleeding (UGIB) in Japanese patients taking antithrombotic agents.

METHODS

We retrospectively investigated the medical records of 560 patients who underwent emergency endoscopy for UGIB from 2002 to 2013. The patients were divided into two groups: group A, antithrombotic agent use; and group NA, no antithrombotic agent use. We compared clinical characteristics, comorbidities, and causes of UGIB between the groups. We also investigated management with antithrombotics.

RESULTS

Of 560 patients with UGIB, 27.5% were taking antithrombotics, and this proportion gradually increased during the study period. Mean hemoglobin levels on admission were significantly lower in group A (8.0 ± 1.7 g/dL) than in group NA (8.9 ± 2.9 g/dL) (P < 0.001). Patients in group A developed more gastric ulcers and multiple ulcers than did patients in group NA. Incidence of Forrest Ia-type bleeding was lower in group A than in group NA (P < 0.001), and the rate of endoscopic hemostasis was significantly higher in group A (98.7%) than in group NA (94.3%) (P = 0.022). After the release of the 2012 Japan Gastroenterological Endoscopy Society guidelines, the antithrombotic agent cessation periods were significantly shortened (P < 0.001).

CONCLUSIONS

Among patients with UGIB, those taking antithrombotics exhibited more severe clinical signs. However spurting hemorrhage was rare. Antithrombotics may be resumed early after endoscopic hemostasis.

Patterns of Antiplatelet Therapy in Patients Who Have Experienced an Acute Coronary Event: A Descriptive Study in UK Primary Care

BACKGROUND

Antiplatelet (AP) therapy is well established for the secondary prevention of acute coronary events. However, patients may discontinue treatment, often owing to gastrointestinal (GI) complications, leaving them at elevated risk of recurrent cardiovascular events.

OBJECTIVES

This descriptive retrospective study assessed trends in prescription of AP agents and coprescription of gastroprotective therapy, after an acute coronary event. Discontinuation of AP therapy within 2 years of an event and factors predicting discontinuation were investigated.

METHODS

The study was conducted in a UK primary care setting from 2000 to 2008; a total of 27, 351 patients aged 50 to 84 years were included in the analysis. Main outcome measures were exposures to low-dose acetylsalicylic acid (ASA), clopidogrel, and proton pump inhibitors (PPIs).

RESULTS

At 90 days after an acute coronary event, 85.9% of patients had been prescribed some form of AP therapy and 33.6% of patients who were issued at least 1 ASA prescription in this period were also issued a PPI prescription. The use of dual antiplatelet therapy (DAT) 90 days after an event increased from 2% in 2000 to over 50% in 2008. An estimated 15.1% of patients on ASA monotherapy and 37.5% on DAT discontinued treatment within 1 year. A bleeding event during follow-up, including upper GI bleeding or hemorrhagic stroke, was the strongest predictor of discontinuation.

CONCLUSION

Although most patients were prescribed AP therapy in the 90 days following an acute coronary event, a substantial proportion discontinued DAT or ASA monotherapy within 1 year. It is essential that physicians consider strategies to reduce the risk of discontinuation of AP therapy.

Anticoagulant-related gastrointestinal bleeding--could this facilitate early detection of benign or malignant gastrointestinal lesions?

INTRODUCTION

The higher incidence of gastrointestinal (GI) bleeding with the non-vitamin K oral anticoagulants (NOACs) may be related to pre-existing malignancies; diagnostic measures triggered by these bleedings could lead to early detection of these malignancies.

METHODS

We retrieved the preferred terms on GI bleeding and GI cancer reported as adverse events (AEs) from phase III studies in patients with atrial fibrillation for each NOAC on ClinicalTrials.gov . We also analyzed the RE-LY trial database.

RESULTS

From ClinicalTrials.gov , AE-GI bleeding incidence was: dabigatran 110 mg b.i.d. (D110: 1.42% versus 1.37%), dabigatran 150 mg b.i.d. (D150: 1.93% versus 1.37%), rivaroxaban (3.52% versus 2.68%), and apixaban (1.93% versus 1.59%), compared with warfarin, respectively. The incidence of AE-GI cancer was similar between the NOACs (D110 [0.79%], D150 [0.61%], rivaroxaban [0.83%], and apixaban [0.69%]), but numerically higher compared with warfarin (0.37%; 0.73%; 0.57%, respectively). In the RE-LY database, the same pattern was seen for dabigatran, with an association between GI bleeding and GI cancer diagnosis.

CONCLUSION

Anticoagulant-related GI bleeding may represent the unmasking of pre-existing malignancies leading to increased detection of GI cancer. This may be especially in the first month of treatment and could explain the numerically higher numbers of GI malignancies observed with NOACs.

Gastrointestinal comorbidities associated with atrial fibrillation

This observational study was conducted to describe the risk of gastrointestinal (GI) events among patients with atrial fibrillation (AF). We analyzed Thomson Reuters MarketScan® data from 2005 to 2009. Subjects aged ≥18 years with ≥ 1 AF diagnosis were selected. GI events were identified from claims with a primary or secondary diagnosis code for any GI condition. The risk of GI events was assessed using cumulative incidence (new GI events/patients with AF without GI condition at baseline) and incidence rates (IRs), calculated as the number of patients with new GI events divided by patient-years of observation. In addition, the CHADS₂ score was evaluated at baseline to determine the patient’s risk of stroke. A total of 557,123 AF patients were identified. The mean (median) AF patient age was 68.2 years (70); 45% were female. The cumulative incidences of any GI event and dyspepsia were 40% and 19%, respectively. The corresponding IRs were 38.8 and 14.7 events per 100 patient–years. IRs of any GI events for female and male patients were 43.6 and 35.5; for patients in the age groups <65, 65–74, 75–84, and ≥85 years, IRs were 32.3, 38.9, 44.6, and 52.7; for patients with a CHADS₂ score of 0, 1–2, 3–4, and 5–6, IRs were 30.3, 41.6, 56.9, and 74.5, respectively. In this large claims database, 40% of AF patients experienced a GI event, predominantly dyspepsia. Physicians should take age and comorbidities into consideration when managing AF patients.

Use of proton pump inhibitors after antireflux surgery: a nationwide register-based follow-up study

OBJECTIVE

Antireflux surgery (ARS) has been suggested as an alternative to lifelong use of proton pump inhibitors (PPI) in reflux disease. Data from clinical trials on PPI use after ARS have been conflicting. We investigated PPI use after ARS in the general Danish population using nationwide healthcare registries.

DESIGN

A nationwide retrospective follow-up study of all patients aged ≥18 and undergoing first-time ARS in Denmark during 1996-2010. Two outcome measures were used: redemption of first PPI prescription after ARS (index prescription) and a marker of long-term use, defined by an average PPI use of ≥180 defined daily doses (DDDs) per year. Kaplan-Meier curves and Cox proportional hazards model were used for statistics.

RESULTS

3465 patients entered the analysis. 12.7% used no PPI in the year before surgery, while 14.2%, 13.4% and 59.7% used 1-89 DDD, 90-179 DDD and ≥180 DDD, respectively. Five-, 10- and 15-year risks of redeeming index PPI prescription were 57.5%, 72.4% and 82.6%, respectively. Similarly, 5-, 10- and 15-year risks of taking up long-term PPI use were 29.4%, 41.1% and 56.6%. Female gender, high age, ARS performed in most recent years, previous use of PPI and use of nonsteroidal anti-inflammatory drugs or antiplatelet therapy significantly increased the risk of PPI use.

CONCLUSIONS

Risk of PPI use after ARS was higher than previously reported, and more than 50% of patients became long-term PPI users 10-15 years postsurgery. Patients should be made aware that long-term PPI therapy is often necessary after ARS.

Risk of upper gastrointestinal bleeding from different drug combinations

BACKGROUND & AIMS

Concomitant use of nonsteroidal anti-inflammatory drugs (NSAIDs) and low-dose aspirin increases the risk of upper gastrointestinal bleeding (UGIB). Guidelines suggest avoiding certain drug combinations, yet little is known about the magnitude of their interactions. We estimated the risk of UGIB during concomitant use of nonselective (ns)NSAIDs, cyclooxygenase -2 selective inhibitors (COX-2 inhibitors), and low-dose aspirin with other drugs.

METHODS

We performed a case series analysis of data from 114,835 patients with UGIB (930,888 person-years of follow-up) identified from 7 population-based health care databases (approximately 20 million subjects). Each patient served as his or her own control. Drug exposure was determined based on prescriptions of nsNSAIDs, COX-2 inhibitors, or low-dose aspirin, alone and in combination with other drugs that affect the risk of UGIB. We measured relative risk (incidence rate ratio [IRR] during drug exposure vs nonexposure) and excess risk due to concomitant drug exposure (relative excess risk due to interaction [RERI]).

RESULTS

Monotherapy with nsNSAIDs increased the risk of diagnosis of UGIB (IRR, 4.3) to a greater extent than monotherapy with COX-2 inhibitors (IRR, 2.9) or low-dose aspirin (IRR, 3.1). Combination therapy generally increased the risk of UGIB; concomitant nsNSAID and corticosteroid therapies increased the IRR to the greatest extent (12.8) and also produced the greatest excess risk (RERI, 5.5). Concomitant use of nsNSAIDs and aldosterone antagonists produced an IRR for UGIB of 11.0 (RERI, 4.5). Excess risk from concomitant use of nsNSAIDs with selective serotonin reuptake inhibitors (SSRIs) was 1.6, whereas that from use of COX-2 inhibitors with SSRIs was 1.9 and that for use of low-dose aspirin with SSRIs was 0.5. Excess risk of concomitant use of nsNSAIDs with anticoagulants was 2.4, of COX-2 inhibitors with anticoagulants was 0.1, and of low-dose aspirin with anticoagulants was 1.9.

CONCLUSIONS

Based on a case series analysis, concomitant use of nsNSAIDs, COX-2 inhibitors, or low-dose aspirin with SSRIs significantly increases the risk of UGIB. Concomitant use of nsNSAIDs or low-dose aspirin, but not COX-2 inhibitors, with corticosteroids, aldosterone antagonists, or anticoagulants produces significant excess risk of UGIB.

Clinical management of esophagogastroduodenoscopy by clinicians under the former guidelines of the Japan Gastroenterological Endoscopy Society for patients taking anticoagulant and antiplatelet medications

BACKGROUND

The 2005 Japan Gastroenterological Endoscopy Society (JGES) guidelines for the management of antithrombotic drugs focused on the increasing risks of bleeding, even from biopsy during scheduled esophagogastroduodenoscopy (EGD). The new 2012 guidelines emphasized the prevention of thromboembolic complications. To compare with the new guidelines, we investigated the clinical management of EGD by clinicians under the former JGES guidelines for patients taking antithrombotic agents.

METHODS

Medical records of 4574 patients (mean age 63.4 years, range 3-96 years, male/female ratio 2805/1769) who underwent scheduled EGD from April 2011 to March 2012 were reviewed retrospectively. The prescribed agents, pre-existing comorbidities, drug cessation before EGD, bleeding, and thromboembolic complications were investigated.

RESULTS

Five hundred forty-six patients (12.0 %) were taking antithrombotic drugs (aspirin, 313; warfarin, 134; cilostazol, 57; clopidogrel, 59; ethylicosapentate, 40; prostaglandin preparations, 41; ticlopidine, 29; icosapentate, 24; dipyridamole, 4); 116 and 29 patients, respectively, were managed with a combination of 2 or 3 agents. Among 490 patients whose medical records were precisely documented, 40.6 % underwent EGD without cessation. Bleeding and thromboembolic complications were not observed. The most common pre-existing comorbidity was ischemic heart disease (27.9 %), followed by carotid or intracranial large artery atherosclerosis (20.5 %), cerebral infarction or transient ischemic attack (20.3 %), and atrial fibrillation (15.9 %). Patients with pre-existing comorbidity requiring anticoagulants frequently underwent EGD without cessation.

CONCLUSION

We revealed the low impact of the 2005 JGES guidelines on the management of antithrombotic drugs. Our physicians have reasonably decided to continue antithrombotic drugs before EGD according to the risk of thromboembolism.

The role of capsule endoscopy in the evaluation and treatment of obscure-overt gastrointestinal bleeding during daily clinical practice: a prospective multicenter study

OBJECTIVE

Capsule endoscopy (CE) is most commonly performed to evaluate obscure gastrointestinal bleeding (GIB). However, at present the role of CE in patients with obscure-overt GIB especially during daily clinical practice is unknown. The aim of the present study was to investigate the diagnostic yield and the impact of CE on the management of patients with obscure-overt GIB.

MATERIAL AND METHODS

Between January 2007 and December 2011 we prospectively included all patients with obscure-overt GIB who underwent CE after negative bidirectional endoscopy. CE findings revealing the cause of bleeding, type of therapeutic intervention and clinical variables associated with positive CE and recurrence of GIB were evaluated.

RESULTS

One hundred and eighteen patients with a median age of 66 years (range 8-89 years) were enrolled in the final analysis. The overall diagnostic yield of the CE was 66.9%. The most common findings were angiodysplasias (33.1%), followed by ulcer (23.7%), and tumors (6.8%). Age (p = 0.001) and cardiovascular disease (p = 0.007) were significant clinical variables predicting the higher incidence of angiodysplasias. Specific therapeutic interventions were undertaken in 54 patients with positive CE (68.4%). Recurrence of GIB was observed in one patient with negative CE (2.6%) and 16 patients with positive CE (20.3%). Univariate and multivariate analysis showed high age and no therapeutic intervention as significant factors associated with recurrent bleeding.

CONCLUSIONS

CE represents a promising diagnostic method in the investigation of obscure-overt GIB, with significant impact on its clinical management in daily clinical practice.

Comparative effects of the anti-platelet drugs, clopidogrel, ticlopidine, and cilostazol on aspirin-induced gastric bleeding and damage in rats

AIMS

The present study compared the effects of frequently used anti-platelet drugs, such as clopidogrel, ticlopidine, and cilostazol, on the gastric bleeding and ulcerogenic responses induced by intraluminal perfusion with 25 mM aspirin acidified with 25 mM HCl (acidified ASA) in rats.

MAIN METHODS

The stomach was perfused with acidified ASA at a rate of 0.4 ml/min for 60 min under urethane anesthesia, and gastric bleeding was measured as the concentration of hemoglobin in the luminal perfusate, which was collected every 15 min. Clopidogrel (10-100mg/kg), ticlopidine (10-300 mg/kg), or cilostazol (3-30 mg/kg) was given p.o. 24h or 90 min before the perfusion of acidified ASA, respectively.

KEY FINDINGS

Perfusion of the stomach with acidified ASA alone led to slight bleeding and lesions in the stomach. The pretreatment with clopidogrel, even though it did not cause bleeding or damage by itself, dose-dependently increased the gastric bleeding and ulcerogenic responses induced by acidified ASA. Ticlopidine also aggravated the severity of damage by increasing gastric bleeding, and the effects of ticlopidine at 300 mg/kg were equivalent to those of clopidogrel at 100mg/kg. In contrast, cilostazol dose-dependently decreased gastric bleeding and damage in response to acidified ASA.

SIGNIFICANCE

These results demonstrated that clopidogrel and ticlopidine, P2Y12 receptor inhibitors, increased gastric bleeding and ulcerogenic responses to acidified ASA, to the same extent, while cilostazol, a phosphodiesterase III inhibitor, suppressed these responses. Therefore, cilostazol may be safely used in dual anti-platelet therapy combined with ASA, without increasing the risk of gastric bleeding.

Gastric mucosal injury induced by dual antiplatelet drugs in rats

AIM: To investigate the effect of different antiplatelet drugs on gastric mucosal injury in rats and the possible mechanisms involved.

METHODS: Eighty 6-7-week-old male SD rats were randomly allocated into four groups. Except a negative control group, the other three groups were given clopidogrel [7.81 mg/(kg•d), n = 20], aspirin [10.41 mg/(kg•d), n = 20] and clopidogrel plus aspirin (n = 20), respectively. The drugs were intragastrically administered once daily, and the negative control group was given normal saline (n = 20). All rats received operation after the final intragastric administration to observe gastric injury. The degree of gastric and small intestinal mucosal injury was assessed by HE staining, and the expression of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in gastric mucosal cells was detected by immunohistochemistry.

RESULTS: The scores of gross and pathological lesions were significantly higher in each drug treatment group than in the negative control group (P < 0.01), in the aspirin group than in the clopidogrel group (13.4000 ± 3.28634 vs 8.8000 ± 1.48324, P < 0.01), and in the combination group than in the two monotherapy groups (P < 0.01). Immunohistochemistry analysis revealed that the expression of TNF-α and IL-1β in the gastric and small intestinal mucosa was significantly higher in each drug treatment group than in the negative control group (P < 0.01), in the aspirin group than in the clopidogrel group (P < 0.01), and in the combination group than in the two monotherapy groups (P < 0.01).

CONCLUSION: Routine doses of antiplatelet drugs can cause gastrointestinal injury in rats, and the combination of antiplatelet drugs aggravates the injury compared with monotherapy. The high expression of TNF-α and IL-1β may be involved in mucosal injury induced by antiplatelet drugs.

Opposing effects of aspirin and anticoagulants on morbidity and mortality in patients with upper gastrointestinal bleeding

OBJECTIVE

We aimed to determine the effect of antithrombotics on in-hospital mortality and morbidity in patients with peptic ulcer disease-related upper gastrointestinal bleeding (PUD-related UGIB).

METHODS

The study cohort was retrospectively selected from a tertiary center database of patients with PUD-related UGIB, defined as bleeding due to gastric or duodenal ulcers, or erosive duodenitis, gastritis or esophagitis. Outcomes were compared among patient groups based on their antithrombotic medications before admission. Patients on no antithrombotics served as controls. The composite adverse outcomes, in-hospital mortality, rebleeding and/or need for surgery were measured. Severe bleeding and in-hospital complications were also recorded.

RESULTS

Of 398 patients with PUD-related UGIB, 44.5% were on aspirin or anticoagulants only. The composite adverse outcome was most common in patients taking anticoagulants only (40.5%), intermediate in controls (23.1%) and least in those taking aspirin only (12.1%). On multivariate analysis, patients taking aspirin alone had a significantly lower risk of adverse outcome events (odds ratio [OR] 0.4, 95% CI 0.2-0.8) and a shorter length of hospital stay (regression coefficient = -3.4, 95% CI [-6.6, -0.6]). In contrast, taking anticoagulants was associated with a greater risk of adverse outcome events (OR 2.3, 95% CI 1.0-5.3), severe bleeding (OR 2.6, 95% CI 1.2-5.8) and in-hospital complications (OR 2.9, 95% CI 1.3-6.6).

CONCLUSIONS

Patients with PUB-related UGIB while taking aspirin had fewer adverse outcomes compared with those taking anticoagulants. Aspirin may have beneficial effects in this population.

Validation study in four health-care databases: upper gastrointestinal bleeding misclassification affects precision but not magnitude of drug-related upper gastrointestinal bleeding risk

OBJECTIVE

To evaluate the accuracy of disease codes and free text in identifying upper gastrointestinal bleeding (UGIB) from electronic health-care records (EHRs).

STUDY DESIGN AND SETTING

We conducted a validation study in four European electronic health-care record (EHR) databases such as Integrated Primary Care Information (IPCI), Health Search/CSD Patient Database (HSD), ARS, and Aarhus, in which we identified UGIB cases using free text or disease codes: (1) International Classification of Disease (ICD)-9 (HSD, ARS); (2) ICD-10 (Aarhus); and (3) International Classification of Primary Care (ICPC) (IPCI). From each database, we randomly selected and manually reviewed 200 cases to calculate positive predictive values (PPVs). We employed different case definitions to assess the effect of outcome misclassification on estimation of risk of drug-related UGIB.

RESULTS

PPV was 22% [95% confidence interval (CI): 16, 28] and 21% (95% CI: 16, 28) in IPCI for free text and ICPC codes, respectively. PPV was 91% (95% CI: 86, 95) for ICD-9 codes and 47% (95% CI: 35, 59) for free text in HSD. PPV for ICD-9 codes in ARS was 72% (95% CI: 65, 78) and 77% (95% CI: 69, 83) for ICD-10 codes (Aarhus). More specific definitions did not have significant impact on risk estimation of drug-related UGIB, except for wider CIs.

CONCLUSIONS

ICD-9-CM and ICD-10 disease codes have good PPV in identifying UGIB from EHR; less granular terminology (ICPC) may require additional strategies. Use of more specific UGIB definitions affects precision, but not magnitude, of risk estimates.

Measures of 'exposure needed for one additional patient to be harmed' in population-based case-control studies

PURPOSE

The magnitude of risk for adverse drug reactions may be communicated by a measure of 'exposure needed for one additional patient to be harmed' (ENH). We present four ENH measures, based on four different counterfactual contrasts, as illustrated by the known effects of NSAID use on peptic ulcer bleeding.

METHODS

The four measures were basic ENH (estimating the excess risk when treating the entire source population versus treating no one), age-restricted ENH (the entire source population above, e.g. 50 years old treated versus no one above 50 years old treated), standardised ENH (a population of similar age and gender distribution as those actually treated versus same subjects not treated) and naturalistic ENH (those actually treated versus same subjects not treated). Data were derived from a case-control dataset on NSAIDs and severe peptic ulcer bleeding, collected in Funen County in 1995-2006. We incorporated prescription and census data to account for the source population's drug use.

RESULTS

Estimates of basic, age-restricted, standardised and naturalistic ENH were 619 person-years (py) (95% confidence interval (CI): 558-684), 223 py (CI: 201-246), 131 py (CI: 118-144) and 162 py (CI: 151-173). The age-restricted ENH showed strong dependence on the chosen age limit.

CONCLUSION

The differing counterfactual contrasts underlying the ENH result in widely different estimates. These differences reflect the clinical and epidemiological aspects of NSAID-related peptic ulcer bleeding. The ultimate choice of ENH measure will depend on epidemiological or clinical considerations and on availability of data.

Is bleeding a necessary evil? The inherent risk of antithrombotic pharmacotherapy used for stroke prevention in atrial fibrillation

Current European atrial fibrillation (AF) guidelines have assigned a strong recommendation for the initiation of antithrombotic therapy to prevent thromboembolism in all but those AF patients at low risk (or with contraindications). Furthermore, the selection of antithrombotic therapy is based on the absolute risks of thromboembolism and bleeding, and the relative risk and benefit for a given patient. By their very mechanism of action, antithrombotic agents used for stroke prevention in AF will potentially increase the risk of bleeding events. Moreover, the introduction of novel oral anticoagulation agents have introduced new, hitherto ill-defined, deficiencies in the authors' knowledge with respect to anticoagulation monitoring, availability of direct antidotes, drug-drug interactions and the ability to appropriately control and reverse their actions if bleeding events occur. The authors present a comprehensive review on all aspects of bleeding related to currently licensed antithrombotic agents used for stroke prevention in patients with AF.

Major bleeding in patients with atrial fibrillation receiving apixaban or warfarin: The ARISTOTLE Trial (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation): Predictors, Characteristics, and Clinical Outcomes

OBJECTIVES

This study sought to characterize major bleeding on the basis of the components of the major bleeding definition, to explore major bleeding by location, to define 30-day mortality after a major bleeding event, and to identify factors associated with major bleeding.

BACKGROUND

Apixaban was shown to reduce the risk of major hemorrhage among patients with atrial fibrillation in the ARISTOTLE (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation) trial.

METHODS

All patients who received at least 1 dose of a study drug were included. Major bleeding was defined according to the criteria of the International Society on Thrombosis and Haemostasis. Factors associated with major hemorrhage were identified using a multivariable Cox model.

RESULTS

The on-treatment safety population included 18,140 patients. The rate of major hemorrhage among patients in the apixaban group was 2.13% per year compared with 3.09% per year in the warfarin group (hazard ratio [HR] 0.69, 95% confidence interval [CI]: 0.60 to 0.80; p < 0.001). Compared with warfarin, major extracranial hemorrhage associated with apixaban led to reduced hospitalization, medical or surgical intervention, transfusion, or change in antithrombotic therapy. Major hemorrhage followed by mortality within 30 days occurred half as often in apixaban-treated patients than in those receiving warfarin (HR 0.50, 95% CI: 0.33 to 0.74; p < 0.001). Older age, prior hemorrhage, prior stroke or transient ischemic attack, diabetes, lower creatinine clearance, decreased hematocrit, aspirin therapy, and nonsteroidal anti-inflammatory drugs were independently associated with an increased risk.

CONCLUSIONS

Apixaban, compared with warfarin, was associated with fewer intracranial hemorrhages, less adverse consequences following extracranial hemorrhage, and a 50% reduction in fatal consequences at 30 days in cases of major hemorrhage.

Potential therapeutic competition in community-living older adults in the U.S.: use of medications that may adversely affect a coexisting condition

OBJECTIVE

The 75% of older adults with multiple chronic conditions are at risk of therapeutic competition (i.e. treatment for one condition may adversely affect a coexisting condition). The objective was to determine the prevalence of potential therapeutic competition in community-living older adults.

METHODS

Cross-sectional descriptive study of a representative sample of 5,815 community-living adults 65 and older in the U.S, enrolled 2007-2009. The 14 most common chronic conditions treated with at least one medication were ascertained from Medicare claims. Medication classes recommended in national disease guidelines for these conditions and used by ≥ 2% of participants were identified from in-person interviews conducted 2008-2010. Criteria for potential therapeutic competition included: 1), well-acknowledged adverse medication effect; 2) mention in disease guidelines; or 3) report in a systematic review or two studies published since 2000. Outcomes included prevalence of situations of potential therapeutic competition and frequency of use of the medication in individuals with and without the competing condition.

RESULTS

Of 27 medication classes, 15 (55.5%) recommended for one study condition may adversely affect other study conditions. Among 91 possible pairs of study chronic conditions, 25 (27.5%) have at least one potential therapeutic competition. Among participants, 1,313 (22.6%) received at least one medication that may worsen a coexisting condition; 753 (13%) had multiple pairs of such competing conditions. For example, among 846 participants with hypertension and COPD, 16.2% used a nonselective beta-blocker. In only 6 of 37 cases (16.2%) of potential therapeutic competition were those with the competing condition less likely to receive the medication than those without the competing condition.

CONCLUSIONS

One fifth of older Americans receive medications that may adversely affect coexisting conditions. Determining clinical outcomes in these situations is a research and clinical priority. Effects on coexisting conditions should be considered when prescribing medications.

Using risk model judgements to better understand perceptions of synergistic risks

Numerous scientific studies show that risk factors can interact to synergistically increase the likelihood of certain adverse and life-threatening outcomes. Yet, the extent to which individuals know that specific risk factor combinations present 'synergistic risks' is unclear and little is known about the determinants of such knowledge. This is largely because epistemological progress concerning this topic has been frustrated by a reliance on metrics that have latterly been judged to be of questionable validity. To address this issue, this paper presents two studies that assess an alternative approach (i.e., risk model judgements) which requires respondents to judge the risk for a factor combination relative to, rather than in isolation from, the risk attributable to each constituent factor. Results from both studies indicate that risk model judgements overcome the drawbacks of traditional metrics. More importantly, the results provide epistemological insights into what can determine whether an individual understands that a factor combination presents a synergistic risk; these determinants include experiential and intuitive insights into the effects of combining specific risk factors, domain-specific judgemental experience and exposure to effective learning opportunities. These findings can be utilized in interventions aimed at helping individuals to make better decisions concerning multiple risk factors.

Low-dose aspirin and upper gastrointestinal bleeding in primary versus secondary cardiovascular prevention: a population-based, nested case-control study

BACKGROUND

The benefit-risk profile of low-dose aspirin in primary prevention of cardiovascular disease is unclear. We sought to quantify upper gastrointestinal bleeding (UGIB) risk associated with low-dose aspirin in secondary versus primary prevention patients.

METHODS AND RESULTS

We performed a population-based nested case-control study using The Health Improvement Network (THIN) Database between 2000 and 2007. We identified 2049 cases of UGIB and 20,000 controls, frequency-matched to the cases on age, sex, and calendar year, who were subdivided into primary (without previous cardiovascular disease) and secondary (with previous cardiovascular disease) prevention populations. We estimated the relative risk of UGIB associated with the use of low-dose aspirin by multivariate logistic regression. The UGIB risk in patients taking low-dose aspirin relative to nonusers was significantly higher in the primary (adjusted relative risk, 1.90; 95% confidence interval, 1.59-2.26) than in the secondary (relative risk, 1.40; 95% confidence interval, 1.14-1.72; P value for the difference=0.0014) prevention cohort. However, as the baseline risk of UGIB was lower in the primary than in the secondary prevention cohort, numbers needed to harm per 1 year of low-dose aspirin use were 601 and 391 for primary and secondary prevention, respectively.

CONCLUSIONS

The relative risk of UGIB in patients taking low-dose aspirin is higher when used for primary than for secondary cardiovascular disease prevention, but this difference is more than compensated by the lower baseline risk in the primary prevention population. Such estimates are important for an assessment of the net clinical benefit in primary prevention.

Simultaneous intrahepatic and subgaleal hemorrhage in antiphospholipid syndrome following anticoagulation therapy

Warfarin is a widely used anticoagulant. Interindividual differences in drug response, a narrow therapeutic range and the risk of bleeding render warfarin difficult to use clinically. An 18-year-old woman with antiphospholipid syndrome received long-term warfarin therapy for a recurrent deep vein thrombosis. Six years later, she developed right flank pain. We diagnosed intrahepatic and subgaleal hemorrhages secondary to anticoagulation therapy. After stopping oral anticoagulation, a follow-up computed tomography showed improvement in the hemorrhage. After restarting warfarin because of a recurrent thrombosis, the intrahepatic hemorrhage recurred. We decided to start clopidogrel and hydroxychloroquine instead of warfarin. The patient has not developed further recurrent thrombotic or bleeding episodes. Intrahepatic hemorrhage is a very rare complication of warfarin, and our patient experienced intrahepatic and subgaleal hemorrhage although she did not have any risk factors for bleeding or instability of the international normalized ratio control.

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.

Risk of gastrointestinal bleeding in patients undergoing total hip or knee replacement compared with matched controls: a nationwide cohort study

OBJECTIVES

Gastrointestinal (GI) bleeding may impose a serious threat in patients undergoing total hip or knee replacement (THR/TKR). The objectives of this study are to evaluate the timing of GI bleeding following THR/TKR and to determine the effect modification by proton pump inhibitor (PPI) use.

METHODS

In a nationwide Danish cohort study, we selected all patients with a primary THR/TKR between 1998 and 2007 (n=95,115). Three control subjects without THR/TKR were matched by age, sex, and region. We calculated disease and medication adjusted (adj.) Hazard ratios (HRs) for GI bleeding with THR/TKR vs. controls. PPI use was assessed in the previous 3 months (in a time-dependent manner).

RESULTS

We identified a 6-fold increased risk of GI bleeding during the first 2 weeks following THR (adj. HR, 6.02; 95% confidence interval (CI), 4.06-8.92) and a 2.3-fold increased risk for TKR patients (adj. HR, 2.30; 95% CI, 1.17-4.54), both vs. matched controls. The elevated risk lasted longer in THR patients (12 weeks) as compared with TKR patients (6 weeks). PPI use lowered the HR for GI bleeding by 74% during the first 6 weeks following THR, but not TKR.

CONCLUSIONS

This study demonstrated an increased risk of GI bleeding during the first 2 weeks following THR (6-fold) and TKR (2.3-fold), and remained increased for up to 6 (TKR) to 12 weeks (THR) after surgery. PPI use substantially lowered this elevated risk in THR patients, but not in TKR patients.

New oral anticoagulants increase risk for gastrointestinal bleeding: a systematic review and meta-analysis

BACKGROUND & AIMS

A new generation of oral anticoagulants (nOAC), which includes thrombin and factor Xa inhibitors, has been shown to be effective, but little is known about whether these drugs increase patients' risk for gastrointestinal bleeding (GIB). Patients who require OAC therapy frequently have significant comorbidities and may also take aspirin and/or thienopyridines. We performed a systematic review and meta-analysis of the risk of GIB and clinically relevant bleeding in patients taking nOAC.

METHODS

We queried MEDLINE, EMbase, and the Cochrane library (through July 2012) without language restrictions. We analyzed data from 43 randomized controlled trials (151,578 patients) that compared nOAC (regardless of indication) with standard care for risk of bleeding (19 trials on GIB). Odds ratios (ORs) were estimated using a random-effects model. Heterogeneity was assessed with the Cochran Q test and the Higgins I(2) test.

RESULTS

The overall OR for GIB among patients taking nOAC was 1.45 (95% confidence interval [CI], 1.07-1.97), but there was substantial heterogeneity among studies (I2, 61%). Subgroup analyses showed that the OR for atrial fibrillation was 1.21 (95% CI, 0.91-1.61), for thromboprophylaxis after orthopedic surgery the OR was 0.78 (95% CI, 0.31-1.96), for treatment of venous thrombosis the OR was 1.59 (95% CI, 1.03-2.44), and for acute coronary syndrome the OR was 5.21 (95% CI, 2.58-10.53). Among the drugs studied, the OR for apixaban was 1.23 (95% CI, 0.56-2.73), the OR for dabigatran was 1.58 (95% CI, 1.29-1.93), the OR for edoxaban was 0.31 (95% CI, 0.01-7.69), and the OR for rivaroxaban was 1.48 (95% CI, 1.21-1.82). The overall OR for clinically relevant bleeding in patients taking nOAC was 1.16 (95% CI, 1.00-1.34), with similar trends among subgroups.

CONCLUSIONS

Studies on treatment of venous thrombosis or acute coronary syndrome have shown that patients treated with nOAC have an increased risk of GIB, compared with those who receive standard care. Better reporting of GIB events in future trials could allow stratification of patients for therapy with gastroprotective agents.

Clopidogrel use and short-term mortality after peptic ulcer bleeding: a population-based cohort study

Clopidogrel therapy increases bleeding risk, but whether it influences short-term mortality after peptic ulcer bleeding (PUB) is unknown. The objective was to examine whether clopidogrel use at the time of PUB increases 30-day mortality. We conducted this cohort study in northern Denmark (population 1.7 million). We used the Danish National Patient Registry, covering all hospitals, to identify all patients with a first-ever inpatient diagnosis of endoscopically or surgically confirmed PUB between 1998 and 2008 and their comorbidities. From the prescription database in the region, we ascertained the use of clopidogrel at the time of admission (current use) or before admission (former use) and use of concurrent medications. We obtained mortality data from the Danish Civil Registration System. We used regression modeling to compute mortality rate ratios (MRRs) with 95% confidence intervals (CIs), controlling for potential confounders. We identified 6951 patients with bleeding peptic ulcers. At admission, 122 (1.8%) were current users of clopidogrel, 143 (2.1%) were former users, and 6686 (96.2%) were nonusers. Thirty-day mortality was 5.7% for current users, 7.0% for former users, and 8.0% for nonusers. The adjusted 30-day MRR was reduced in both current and former users, compared with nonusers (MRR = 0.72, 95% CI 0.34, 1.52 and MRR = 0.71, 95% CI 0.38, 1.32, respectively). There was no notable modification of the association within gender or age strata. Although the use of clopidogrel increases the risk of PUB, former use and current use of clopidogrel were not associated with increased short-term mortality after admission for this condition.

Dual antiplatelet therapy can be discontinued at three months after implantation of zotarolimus-eluting stent in patients with coronary artery disease

Dual antiplatelet therapy (DAPT) after percutaneous coronary intervention increases the risk of bleeding. We studied the safety and clinical outcomes of switching from DAPT to aspirin monotherapy at 3 months after ZES implantation. We retrospectively evaluated 168 consecutive patients with coronary artery disease who had been implanted with a ZES from June 2009 through March 2010. After excluding 40 patients according to exclusion criteria such as myocardial infarction, 128 patients were divided into a 3-month DAPT group (67 patients, 88 lesions) and a 12-month conventional DAPT group (61 patients, 81 lesions). Coronary angiographic followup and clinical followup were conducted at more than 8 months and at 12 months after ZES implantation, respectively. Minor and major bleeding events, stent thrombosis (ST), and major adverse cardiac events (MACE) (death, myocardial infarction, cerebrovascular accident, target lesion revascularization, and target vessel revascularization) were evaluated. There were no statistically significant differences in the incidences of ST and MACE between the two groups. The incidence of bleeding events was significantly lower in the 3-month group than in the 12-month group (1.5% versus 11.5%, P < 0.05). DAPT can be safely discontinued at 3 months after ZES implantation, which reduces bleeding risk.