Incidence of Upper and Lower Gastrointestinal Bleeding in New Users of Low-Dose Aspirin

Colorectal cancer initiation: Understanding early-stage disease for intervention

How tumors arise or the cause of precancerous lesions is a fundamental question in cancer biology. It is generally accepted that tumors originate from normal cells that undergo uncontrolled proliferation owing to genetic alterations. At the onset of adenoma formation, cancer driver mutations confer clonal growth advantage, enabling mutant cells to outcompete and eliminate the surrounding healthy cells. Hence, the development of precancerous lesions is not only attributed to the expansion of pre-malignant clones, but also relies on the relative fitness of mutated cells compared to the neighboring cells. Colorectal cancer (CRC) is an excellent model to investigate cancer origin as it follows a stereotypical process from mutant cell hyperplasia to adenoma formation and progression. Here, we review the evolving understanding of colonic tumor development, focusing on how cell intrinsic and extrinsic factors impact cell competition and the "clone war" between cancer-initiating cells and normal stem cells. We also discuss the promises and limitations of targeting cell competitiveness in cancer prevention and early intervention. The field of tumor initiation is currently in its infancy, elucidating the adenoma origin is crucial for designing effective prevention strategies and early treatments before cancer becomes incurable.

Pantoprazole and Vonoprazan Performed Well in Preventing Peptic Ulcer Recurrence in Low-Dose Aspirin Users

BACKGROUND

Low-dose aspirin (LDA) administration is associated with an elevated risk of recurring peptic ulcer (PU) and gastrointestinal (GI) hemorrhage.

AIMS

This systematic review and Bayesian network meta-analysis aimed to comprehensively assess the effectiveness of diverse medications in preventing the recurrence of PU and GI hemorrhage in patients with a history of PU receiving long-term LDA therapy.

METHODS

This systematic review and network meta-analysis followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and was registered on PROSPERO (CRD42023406550). We searched relevant studies in main databases from inception to March 2023. All statistical analyses were performed using R (version 4.1.3), with the "Gemtc" (version 1.0-1) package. The pooled risk ratio (RR), corresponding 95% credible interval (95% CrI), and the surface under the cumulative ranking curve (SUCRA) were calculated.

RESULTS

11 Randomized clinical trials (RCTs) were included. The analysis underscored pantoprazole was the most efficacious for reducing the risk of PU recurrence (RR [95% CrI] = 0.02 [0, 0.28]; SUCRA: 90.76%), followed by vonoprazan (RR [95% CrI] = 0.03 [0, 0.19]; SUCRA: 86.47%), comparing with the placebo group. Pantoprazole also performed well in preventing GI hemorrhage (RR [95% CrI] = 0.01[0, 0.42]; SUCRA: 87.12%) compared with Teprenone.

CONCLUSIONS

For patients with a history of PU receiving LDA, pantoprazole and vonoprazan might be the optimal choices to prevent PU recurrence and GI hemorrhage.

Fecal Occult Blood Screening before Cardiac Surgery

BACKGROUND

Concerns of gastrointestinal (GI) bleeding after cardiac surgery are increasing with increased use of antiplatelets and anticoagulants. We investigated the roles of preoperative screening for fecal occult blood by fecal immunochemical test (FIT) widely used to detect GI bleeding and cancer.

METHODS

A retrospective review was done in 1,663 consecutive patients undergoing FIT before cardiac surgery between years 2012 and 2020. One or two rounds of FIT were performed 2 to 3 weeks before surgery, when antiplatelets and anticoagulants were not suspended yet.

RESULTS

Positive FIT (> 30 μg of hemoglobin/g of feces) was observed in 227 patients (13.7%). Preoperative risk factors for positive FIT included age > 70 years, anticoagulants, and chronic kidney disease. Of those with positive FIT, 180 patients (79%) received preoperative endoscopy, including gastroscopy (n = 139), colonoscopy (n = 9), and both (n = 32), with no findings of bleeding. The most common finding of gastroscopy was atrophic gastritis (36%) while early gastric cancer was detected in 2 patients. The most common finding of colonoscopy was colon polyps (42%) while colorectal cancer was detected in 5 patients. Of 180 FIT-positive patients receiving endoscopy, 8 (4.4%) underwent preoperative GI treatment, while postoperative GI events were documented in 28 (15.6%). Of 1,436 with negative FIT, 21 (1.5%) presented GI complications after surgery.

CONCLUSION

Preoperative FIT, which is influenced by anticoagulant use, has little impacts on identification of GI bleeding sites. However, it may be useful to detect GI malignant lesions, potentially impacting operative risks, surgical strategies, and postoperative management.

Trends in Upper Gastrointestinal Bleeding in Patients on Primary Prevention Aspirin: A Nationwide Emergency Department Sample Analysis, 2016-2020

BACKGROUND

Recent guidelines do not recommend routine use of aspirin for primary cardiovascular prevention (ppASA) and suggest avoidance of ppASA in older individuals due to bleeding risk. However, ppASA is frequently taken without an appropriate indication. Estimates of the incidence of upper gastrointestinal bleeding due to ppASA in the United States are lacking. In this study, we provide national estimates of upper gastrointestinal bleeding incidence, characteristics, and costs in ppASA users from 2016-2020.

METHODS

Primary cardiovascular prevention users (patients on long-term aspirin therapy without cardiovascular disease) presenting with upper gastrointestinal bleeding were identified in the Nationwide Emergency Department Sample using International Statistical Classification of Diseases and Related Health Problems, 10th revision codes. Trends in upper gastrointestinal bleeding incidence, etiology, severity, associated Medicare reimbursements, and the impact of ppASA on bleeding outcomes were assessed with regression models.

RESULTS

From 2016-2020, adjusted incidence of upper gastrointestinal bleeding increased 29.2% among ppASA users, with larger increases for older patients (increase of 41.6% for age 65-74 years and 36.0% for age ≥75 years). The most common etiology among ppASA users was ulcer disease but increases in bleeding incidence due to angiodysplasias were observed. The proportion of hospitalizations with major complications or comorbidities increased 41.5%, and Medicare reimbursements increased 67.6%. Among patients without cardiovascular disease, ppASA was associated with increased odds of hospital admission, red blood cell transfusion, and endoscopic intervention as compared to no ppASA use.

CONCLUSIONS

Considering recent guideline recommendations, the rising incidence, severity, and costs associated with upper gastrointestinal bleeding among patients on ppASA highlights the importance of careful assessment for appropriate ppASA use.

Impact of proton pump inhibitors on the risk of small bowel or colorectal bleeding: A systematic review and meta-analysis

BACKGROUND

Several studies have suggested that the mucosal protective effects of proton pump inhibitors (PPIs) do not extend beyond the duodenum; however, PPIs may cause lower gastrointestinal (LGI) injury, although these relationships have not yet been fully elucidated.

METHODS

We searched all the relevant studies published until September 2022 that examined the risk of PPIs for LGI bleeding. We performed a meta-analysis of the risk of LGI bleeding (small bowel (SB) or colorectal bleeding) between PPI users and non-users. A subgroup analysis of patients consuming aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) was also performed.

RESULTS

Twelve studies with 341,063 participants were included in this meta-analysis. The use of PPIs was associated with the risk of LGI bleeding (odds ratio [OR] [95% confidence interval [CI]] = 1.42 [1.16-1.73]; hazard ratio [HR] [95% CI] = 3.23 [1.56-6.71]). An association between PPI use and the risk of LGI bleeding was also identified in the subgroup of aspirin or NSAID users (OR [95% CI] = 1.64 [1.49-1.80]; HR [95% CI] = 6.55 [2.01-21.33]). In the bleeding site-specific analyses, the risk of SB bleeding was associated with PPI use (OR [95% CI] = 1.54 [1.30-1.84]).

CONCLUSIONS

PPI use was associated with an increased risk of LGI bleeding, particularly SB bleeding. This association was particularly pronounced among aspirin and NSAID users. Inappropriate PPI prescriptions should be avoided in patients with LGI bleeding and a low risk of upper gastrointestinal disease.

Evaluation of the Jichi Medical University diverticular hemorrhage score in the clinical management of acute diverticular bleeding with emergency or elective endoscopy: A pilot study

BACKGROUND AND AIMS

Emergency endoscopic hemostasis for colonic diverticular bleeding is effective in preventing serious consequences. However, the low identification rate of the bleeding source makes the procedure burdensome for both patients and providers. We aimed to establish an efficient and safe emergency endoscopy system.

METHODS

We prospectively evaluated the usefulness of a scoring system (Jichi Medical University diverticular hemorrhage score: JD score) based on our experiences with past cases. The JD score was determined using four criteria: CT evidence of contrast agent extravasation, 3 points; oral anticoagulant (any type) use, 2 points; C-reactive protein ≥1 mg/dL, 1 point; and comorbidity index ≥3, 1 point. Based on the JD score, patients with acute diverticular bleeding who underwent emergency or elective endoscopy were grouped into JD ≥3 or JD <3 groups, respectively. The primary and secondary endpoints were the bleeding source identification rate and clinical outcomes.

RESULTS

The JD ≥3 and JD <3 groups included 35 and 47 patients, respectively. The rate of bleeding source identification, followed by the hemostatic procedure, was significantly higher in the JD ≥3 group than in the JD <3 group (77% vs. 23%, p <0.001), with a higher JD score associated with a higher bleeding source identification rate. No significant difference was observed between the groups in terms of clinical outcomes, except for a higher incidence of rebleeding at one-month post-discharge and a higher number of patients requiring interventional radiology in the JD ≥3 group than in the JD <3 group. Subgroup analysis showed that successful identification of the bleeding source and hemostasis contributed to a shorter hospital stay.

CONCLUSION

We established a safe and efficient endoscopic scoring system for treating colonic diverticular bleeding. The higher the JD score, the higher the bleeding source identification, leading to a successful hemostatic procedure. Elective endoscopy was possible in the JD <3 group when vital signs were stable.

Management of Patients With Acute Lower Gastrointestinal Bleeding: An Updated ACG Guideline

Acute lower gastrointestinal bleeding (LGIB) is a common reason for hospitalization in the United States and is associated with significant utilization of hospital resources, as well as considerable morbidity and mortality. These revised guidelines implement the Grading of Recommendations, Assessment, Development, and Evaluation methodology to propose recommendations for the use of risk stratification tools, thresholds for red blood cell transfusion, reversal agents for patients on anticoagulants, diagnostic testing including colonoscopy and computed tomography angiography (CTA), endoscopic therapeutic options, and management of antithrombotic medications after hospital discharge. Important changes since the previous iteration of this guideline include recommendations for the use of risk stratification tools to identify patients with LGIB at low risk of a hospital-based intervention, the role for reversal agents in patients with life-threatening LGIB on vitamin K antagonists and direct oral anticoagulants, the increasing role for CTA in patients with severe LGIB, and the management of patients who have a positive CTA. We recommend that most patients requiring inpatient colonoscopy undergo a nonurgent colonoscopy because performing an urgent colonoscopy within 24 hours of presentation has not been shown to improve important clinical outcomes such as rebleeding. Finally, we provide updated recommendations regarding resumption of antiplatelet and anticoagulant medications after cessation of LGIB.

Deprescription of aspirin for primary prevention is uncommon at discharge in hospitalised patients with gastrointestinal bleeding

BACKGROUND

Guidelines recommend against aspirin for primary prevention of cardiovascular events in individuals with a history of gastrointestinal bleeding (GIB). It is unknown how often patients on primary prevention aspirin hospitalised with GIB have aspirin discontinued at discharge.

AIMS

To determine the rate of aspirin deprescription and explore long-term outcomes in patients taking aspirin for primary prevention of cardiovascular events.

METHODS

We evaluated all patients hospitalised at Yale-New Haven Hospital between January 2014 and October 2021 with GIB who were on aspirin for primary prevention. Our primary endpoint was the frequency of aspirin deprescription at discharge. Our secondary endpoints were post-discharge hospitalisations for major adverse cardiovascular events (MACE) or GIB. Time-to-event analysis was performed using Kaplan-Meier curves and the log-rank test.

RESULTS

We identified 320 patients with GIB on aspirin for primary prevention: median age was 72 (interquartile range [IQR] 61-81) years and 297 (92.8%) were on aspirin 81 mg daily. Only 25 (9.0%) patients surviving their hospitalisation were deprescribed aspirin at discharge. Among 260 patients with follow-up (median 1103 days; IQR 367-1670), MACE developed post-discharge in 2/25 (8.0%) with aspirin deprescription versus 37/235 (15.7%) with aspirin continuation (log-rank p = 0.28). 0/25 patients with aspirin deprescription had subsequent hospitalisation for GIB versus 17/235 (7.2%) who continued aspirin (log-rank p = 0.13).

CONCLUSIONS

Aspirin for primary cardiovascular prevention was rarely deprescribed at discharge in patients hospitalised with GIB. Processes designed to ensure appropriate deprescription of aspirin are crucial to improve adherence to guidelines, thereby improving the risk-benefit ratio in patients at high risk of subsequent GIB hospitalisations with minimal increased risk of MACE.

Efficacy and Safety of Novel Aspirin Formulations: A Randomized, Double-Blind, Placebo-Controlled Study

Low-dose aspirin represents the best option in the secondary prevention of coronary artery disease, but its extensive use in primary prevention is limited by the occurrence of gastric mucosal lesions and increased risk of bleeding. We investigated the safety profile of a novel sublingual aspirin formulation in 200 healthy volunteers, randomly assigned to ten (n = 20 each) different 7-day once-daily treatment regimens. Gastric mucosal injury based on the modified Lanza score (MLS), the histopathology of gastric mucosa and the serum determination of thromboxane B₂ (TXB₂) and urinary 11-dehydro-TXB₂ levels were evaluated at basal as well as after 7 days of each placebo or aspirin treatment regimen. In Groups A and B (placebo—oral and sublingual, respectively), no changes in MLS and in gastric mucosal micro-vessel diameter were found at day 7. In contrast, in Groups C and D (oral standard aspirin—100 and 50 mg daily, respectively), the median MLS was significantly increased. Very few changes were found in Groups E and F (standard sublingual aspirin—100 and 50 mg, respectively). Groups G and H (oral administration of micronized collagen-cogrinded aspirin) showed gastric protection compared to Groups C and D. Moreover, Groups I and L (sublingual collagen-cogrinded aspirin—100 and 50 mg, respectively) showed a significant reduction (Group I) or total abolition (Group L) of gastric mucosal lesions and no difference compared to the standard one in serum TXB₂ and urinary 11-dehydro-TXB₂ levels. In conclusion, our data show that the new formulation leads to a better safety profile compared to standard aspirin, representing a better therapeutic option for extended use in primary and secondary prevention of cardiovascular diseases.

Diagnosis and management of acute lower gastrointestinal bleeding: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

1: ESGE recommends that the initial assessment of patients presenting with acute lower gastrointestinal bleeding should include: a history of co-morbidities and medications that promote bleeding; hemodynamic parameters; physical examination (including digital rectal examination); and laboratory markers. A risk score can be used to aid, but should not replace, clinician judgment.Strong recommendation, low quality evidence. 2 : ESGE recommends that, in patients presenting with a self-limited bleed and no adverse clinical features, an Oakland score of ≤ 8 points can be used to guide the clinician decision to discharge the patient for outpatient investigation.Strong recommendation, moderate quality evidence. 3 : ESGE recommends, in hemodynamically stable patients with acute lower gastrointestinal bleeding and no history of cardiovascular disease, a restrictive red blood cell transfusion strategy, with a hemoglobin threshold of ≤ 7 g/dL prompting red blood cell transfusion. A post-transfusion target hemoglobin concentration of 7-9 g/dL is desirable.Strong recommendation, low quality evidence. 4 : ESGE recommends, in hemodynamically stable patients with acute lower gastrointestinal bleeding and a history of acute or chronic cardiovascular disease, a more liberal red blood cell transfusion strategy, with a hemoglobin threshold of ≤ 8 g/dL prompting red blood cell transfusion. A post-transfusion target hemoglobin concentration of ≥ 10 g/dL is desirable.Strong recommendation, low quality evidence. 5: ESGE recommends that, in patients with major acute lower gastrointestinal bleeding, colonoscopy should be performed sometime during their hospital stay because there is no high quality evidence that early colonoscopy influences patient outcomes.Strong recommendation, low quality of evidence. 6 : ESGE recommends that patients with hemodynamic instability and suspected ongoing bleeding undergo computed tomography angiography before endoscopic or radiologic treatment to locate the site of bleeding.Strong recommendation, low quality evidence. 7 : ESGE recommends withholding vitamin K antagonists in patients with major lower gastrointestinal bleeding and correcting their coagulopathy according to the severity of bleeding and their thrombotic risk. In patients with hemodynamic instability, we recommend administering intravenous vitamin K and four-factor prothrombin complex concentrate (PCC), or fresh frozen plasma if PCC is not available.Strong recommendation, low quality evidence. 8 : ESGE recommends temporarily withholding direct oral anticoagulants at presentation in patients with major lower gastrointestinal bleeding.Strong recommendation, low quality evidence. 9: ESGE does not recommend withholding aspirin in patients taking low dose aspirin for secondary cardiovascular prevention. If withheld, low dose aspirin should be resumed, preferably within 5 days or even earlier if hemostasis is achieved or there is no further evidence of bleeding.Strong recommendation, moderate quality evidence. 10: ESGE does not recommend routinely discontinuing dual antiplatelet therapy (low dose aspirin and a P2Y12 receptor antagonist) before cardiology consultation. Continuation of the aspirin is recommended, whereas the P2Y12 receptor antagonist can be continued or temporarily interrupted according to the severity of bleeding and the ischemic risk. If interrupted, the P2Y12 receptor antagonist should be restarted within 5 days, if still indicated.Strong recommendation, low quality evidence.

Aspirin in Primary Prevention: What Changed? A Critical Appraisal of Current Evidence

Aspirin has been the mainstay of both secondary and primary prevention of cardiovascular disease for half a century. In 2018, 3 trials showed a modest reduction in cardiovascular outcomes that appeared counterbalanced by the risk of clinically significant bleeding. The latest ACC/AHA primary prevention guidelines downgraded their recommendation for aspirin use in primary prevention to that of physician preference. Despite the consistent and robust evidence previously supporting the use of aspirin in cardiovascular disease prevention, little discussion has been given to mechanisms or analytic explanations for this revision of recommendations. In this review, we explore 3 possible mechanisms that may have contributed to the alteration of our perception of aspirin's role in primary prevention. These include changes in the population potentially using aspirin in primary prevention, changes in cardiovascular disease and its presentation, and changes in aspirin itself. Here we present a translational look at knowledge gaps that should be addressed to better guide contemporary aspirin use in primary prevention. In conclusion, based on these considerations, the current recommendations might be improved by recalibration of the cardiovascular risk threshold above which aspirin should be recommended for primary prevention, including the incorporation of newer risk assessment modalities such as calcium scoring. A second enhancement would be developing a bleeding risk calculator to support clinicians' assessment of risk vs benefit. The use of enteric-coated aspirin vs noncoated aspirin should also be reassessed.

Mechanisms of Colorectal Cancer Prevention by Aspirin-A Literature Review and Perspective on the Role of COX-Dependent and -Independent Pathways

Aspirin, synthesized and marketed in 1897 by Bayer, is one of the most widely used drugs in the world. It has a well-recognized role in decreasing inflammation, pain and fever, and in the prevention of thrombotic cardiovascular diseases. Its anti-inflammatory and cardio-protective actions have been well studied and occur through inhibition of cyclooxygenases (COX). Interestingly, a vast amount of epidemiological, preclinical and clinical studies have revealed aspirin as a promising chemopreventive agent, particularly against colorectal cancers (CRC); however, the primary mechanism by which it decreases the occurrences of CRC has still not been established. Numerous mechanisms have been proposed for aspirin’s chemopreventive properties among which the inhibition of COX enzymes has been widely discussed. Despite the wide attention COX-inhibition has received as the most probable mechanism of cancer prevention by aspirin, it is clear that aspirin targets many other proteins and pathways, suggesting that these extra-COX targets may also be equally important in preventing CRC. In this review, we discuss the COX-dependent and -independent pathways described in literature for aspirin’s anti-cancer effects and highlight the strengths and limitations of the proposed mechanisms. Additionally, we emphasize the potential role of the metabolites of aspirin and salicylic acid (generated in the gut through microbial biotransformation) in contributing to aspirin’s chemopreventive actions. We suggest that the preferential chemopreventive effect of aspirin against CRC may be related to direct exposure of aspirin/salicylic acid or its metabolites to the colorectal tissues. Future investigations should shed light on the role of aspirin, its metabolites and the role of the gut microbiota in cancer prevention against CRC.

Bleeding associated with low-dose aspirin: Comparison of data from the COMPASS randomized controlled trial and routine clinical practice

Randomized controlled trials (RCTs) have strong internal validity but often have limited external validity. Observational studies have good generalizability and an increasing role in key healthcare decision making. We compared incidence rates of intracranial and major gastrointestinal bleeds in the low-dose aspirin arm (N = 9126) of the COMPASS double-blind RCT (conducted at 602 centres in 33 countries) with those from an observational cohort of preventative low-dose aspirin users (N = 54,140) in a primary care database representative of the UK general population - The IQVIA Medical Research Data UK (IMRD-UK). In our observational study analysis, we restricted follow-up to 2 years to be comparable with the duration of the COMPASS trial. Among low-dose aspirin users, incidence rates per 1000 person-years (95% confidence intervals [CIs]) in the IMRD-UK cohort and COMPASS trial participants, respectively, were 0.6 (0.5-0.8) vs. 1.4 (0.9-2.1) for intracranial bleeds, and 3.5 (3.1-3.8) vs. 3.7 (2.9-4.8) for major gastrointestinal bleeds. These broadly comparable bleeding rates among COMPASS trial participants and an observational cohort of low-dose aspirin users in IMRD-UK support the use of the latter for generating robust therapeutic evidence, and indicate that the rates from the COMPASS trial are broadly consistent with realistic population-based rates.

Aspirin for primary prevention of cardiovascular disease: a review of recent literature and updated guideline recommendations

INTRODUCTION

Recent clinical trials evaluating the efficacy of aspirin in primary prevention of atherosclerotic cardiovascular disease (ASCVD) have suggested the risk of aspirin may outweigh its benefit in individuals once thought to be candidates for aspirin therapy. These results led to the publication of updated guideline recommendations in 2019 for aspirin use in primary prevention of cardiovascular disease from the American College of Cardiology (ACC) and American Heart Association (AHA).

AREAS COVERED

Recent clinical trials and guidelines relevant to aspirin for primary prevention of ASCVD were identified using PubMed® (July 1, 2016 to April 1, 2019). Studies were limited to randomized, controlled clinical trials. The most current clinical practice guidelines were prioritized.

EXPERT OPINION

Recent clinical trials demonstrated an increased risk of bleeding associated with aspirin use, which often outweighed cardiovascular risk reduction. In light of this new evidence, the ACC/AHA guidelines recommend aspirin for primary prevention in patients 40-70 years of age at a high ASCVD risk and low bleeding risk, who are unable to optimally control modifiable ASCVD risk factors.

Efficacy of Aspirin in the Primary Prevention of Cardiovascular Diseases and Cancer in the Elderly: A Population-Based Cohort Study in Korea

INTRODUCTION

Aspirin is widely used to prevent cardiovascular diseases (CVDs). However, the balance of its benefits and risks in the primary prevention of CVDs and cancer is unclear, especially in elderly Asians. The present study aimed to evaluate the efficacy of aspirin in the primary prevention of major adverse cardiac and cerebrovascular events (MACCE), bleeding risk, and cancer in elderly Koreans with cardiovascular (CV) risk factors.

METHODS

This retrospective cohort study used data from the Korean National Health Insurance Service-Senior cohort database (2002-2015). Patients aged 60-90 years with hypertension, type 2 diabetes mellitus (T2DM), or dyslipidemia were identified. Aspirin users were compared with non-users using propensity score matching at a 1:3 ratio. The primary outcome was MACCE, a composite of CV mortality, myocardial infarction, and ischemic stroke. The secondary outcomes were the components of MACCE, all-cause mortality, angina pectoris, heart failure, the incidence and mortality of cancer, and the risks of hemorrhagic stroke and gastrointestinal bleeding. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using a Cox proportional hazard model.

RESULTS

A total of 3366 aspirin users and 10,089 non-users were finally included in the study. During a mean follow-up of 7.8 years, the incidence of MACCE was 15.2% in aspirin users and 22.4% in non-users. The risk of MACCE was significantly lower in aspirin users than in non-users (HR 0.76; 95% CI 0.69-0.85), and this risk was significantly reduced in patients using aspirin over 5 years (HR 0.52; 95% CI 0.46-0.60). Aspirin use was associated with a 21% reduction in the risk of primary cancer (HR 0.79; 95% CI 0.70-0.88) and cancer-related mortality (HR 0.72; 95% CI 0.61-0.84). No significant differences in bleeding risks were observed between the two groups.

CONCLUSION

Aspirin reduced the risks of MACCE and cancer without increasing the bleeding risk in elderly Koreans with hypertension, T2DM, or dyslipidemia. Moreover, the benefits of the long-term use of aspirin in reducing the risks of MACCE were demonstrated. However, the decision of using aspirin for primary prevention must be carefully made on an individual basis, while estimating the benefit-risk balance of aspirin.

Effect of Proton Pump Inhibitors on Risks of Upper and Lower Gastrointestinal Bleeding among Users of Low-Dose Aspirin: A Population-Based Observational Study

Estimates of the effect of proton pump inhibitors (PPIs) on risks of upper and lower gastrointestinal bleeding (UGIB and LGIB) among low-dose aspirin users in routine clinical practice are variable (UGIB) or lacking (LGIB). We aimed to establish these risks in the same observational study population. Using UK primary care data, we followed 199,049 new users of low-dose aspirin (75–300 mg/day) and matched non-users at start of follow-up to identify incident UGIB/LGIB cases. In nested case–control analyses, adjusted odds ratios (ORs) were calculated for concomitant PPI use vs. past (discontinued) PPI use among current low-dose aspirin users. For UGIB (n = 987), ORs (95% CIs) were 0.69 (0.54–0.88) for >1 month PPI use and 2.65 (1.62–4.3) for ≤1 month PPI use. Among the latter group, ORs (95% CIs) were 3.05 (1.75–5.33) for PPI initiation after start of aspirin therapy, and 1.66 (0.63–4.36) for PPI initiation on/before start of aspirin therapy. For LGIB (n = 1428), ORs (95% CIs) were 0.98 (0.81–1.17) for >1 month PPI use and 1.12 (0.73–1.71) for ≤1 month PPI use. Among low-dose aspirin users, maintaining PPI use (>1 month) was associated with a significantly reduced UGIB risk. Neither short nor long-term PPI use affected LGIB risk.

Palmatine induces G2/M phase arrest and mitochondrial-associated pathway apoptosis in colon cancer cells by targeting AURKA

Studies have shown that palmatine (PAL) has anti-cancer effects. However, the activity and potential mechanisms of PAL against colorectal cancer remain elusive. The results showed that PAL significantly inhibited the proliferation of colon cancer cells in vitro and in vivo without significant effect on non-tumorigenic colon cells. Target prediction and clinical sample database analysis suggested that PAL may contribute to colon cancer cells phase arrest and apoptosis by targeting aurora kinase A (AURKA). Inhibition and overexpression of AURKA proved that PAL induces G2/M phase arrest and apoptosis in colon cancer cells by targeting AURKA. Moreover, PAL promoted intracellular Reactive oxygen species (ROS) production and decreased mitochondrial membrane potential (ΔΨm). PAL reduced the levels of AURKA, Bcl-xl and Bcl2 proteins, and promoted the expression of pro-apoptotic proteins P53, P73, Caspase3 and Caspase9, as well as the increase of cytochrome c (cyt. c) in cell lysates in vitro and in vivo. Together, our study confirmed that PAL induced G2/M phase arrest and mitochondrial-associated pathway apoptosis in colon cancer cells by targeting AURKA. PAL may provide a novel solution for the treatment of colon cancer by serving as a new AURKA inhibitor.

Global burden of colorectal cancer: emerging trends, risk factors and prevention strategies

Globally, colorectal cancer (CRC) is the third most commonly diagnosed malignancy and the second leading cause of cancer death. Arising through three major pathways, including adenoma-carcinoma sequence, serrated pathway and inflammatory pathway, CRC represents an aetiologically heterogeneous disease according to subtyping by tumour anatomical location or global molecular alterations. Genetic factors such as germline MLH1 and APC mutations have an aetiologic role, predisposing individuals to CRC. Yet, the majority of CRC is sporadic and largely attributable to the constellation of modifiable environmental risk factors characterizing westernization (for example, obesity, physical inactivity, poor diets, alcohol drinking and smoking). As such, the burden of CRC is shifting towards low-income and middle-income countries as they become westernized. Furthermore, the rising incidence of CRC at younger ages (before age 50 years) is an emerging trend. This Review provides a comprehensive summary of CRC epidemiology, with emphasis on modifiable lifestyle and nutritional factors, chemoprevention and screening. Overall, the optimal reduction of CRC incidence and mortality will require concerted efforts to reduce modifiable risk factors, to leverage chemoprevention research and to promote population-wide and targeted screening.

Low-dose aspirin and risk of upper/lower gastrointestinal bleeding by bleed severity: a cohort study with nested case-control analysis using primary care electronic health records from the United Kingdom

Introduction: Risks of low-dose aspirin-associated upper and lower gastrointestinal bleeds (UGIB/LGIB) may vary by severity and presence of cardiovascular disease (CVD). No study has quantified these risks for UGIB and LGIB in the same real-world study population. Patients and methods: Using UK primary care data, 199,049 new users of low-dose aspirin (75-300 mg/day) and 1:1 matched non-users were followed to identify incident UGIB (N = 1843)/LGIB (N = 2763) cases. Nested case-control analyses compared current low-dose aspirin vs. non-use on UGIB/LGIB risk. Results: Adjusted incidence rate ratios (ORs; 95% CIs) were 1.62 (1.42-1.86) for non-fatal UGIB, 1.63 (1.47-1.81) for non-fatal LGIB, 0.77 (0.51-1.16) for fatal UGIB, 1.29 (0.50-3.36) for fatal LGIB. For hospitalizations, adjusted ORs (95% CIs) were 1.55 (1.32-1.81) for UGIB and 1.89 (1.58-2.27) for LGIB; for referred only cases, they were 1.52 (1.26-1.84) for UGIB and 1.54 (1.37-1.73) for LGIB. In primary CVD prevention, adjusted ORs (95% CI) were 1.62 (1.38-1.90) for UGIB and 1.60 (1.42-1.81) for LGIB; in secondary CVD prevention, they were 1.16 (0.89-1.50) for UGIB and 1.67 (1.34-2.09) for LGIB. Conclusion: Low-dose aspirin was associated with increased risks of non-fatal but not fatal UGIB/LGIB. Key message Low-dose aspirin is associated with an increased risks of non-fatal UGIB/LGIB but not fatal UGIB/LGIB.

Modification of gastric cancer risk associated with proton pump inhibitors by aspirin after Helicobacter pylori eradication

Aim

Although proton pump inhibitors (PPIs) can prevent aspirin-induced upper gastrointestinal bleeding, a clinical dilemma exists as long-term use of PPI may also increase the risk of gastric cancer even after Helicobacter pylori (HP) eradication. We aimed to investigate the potential interaction between aspirin and PPIs on GC risk in patients who have HP eradicated.

Results

Of the 63,397 HP eradicated subjects (median follow-up 7.6 years), 153 (0.24%) developed GC. PPIs were associated with a higher GC risk among non-aspirin users (aHR: 3.73, 95% CI:2.11–6.60) but not among aspirin users (aHR: 0.35, 95% CI:0.04–2.74).

Materials and Methods

This is a post-hoc analysis based on a previously published territory-wide retrospective cohort study on the potential risk of PPIs on GC. Adults who had received an outpatient prescription of clarithromycin-based triple therapy for HP between 2003 and 2013 were identified. The adjusted hazard ratio (aHR) of GC with PPIs, stratified according to aspirin use, was calculated by Cox model with propensity score adjustment of other covariates.

Conclusions

The potential harmful effects of PPIs on GC development appear to be limited to non-aspirin users. Co-prescription of PPIs is therefore recommended for HP-eradicated patients who are at risk of aspirin-induced UGIB.

K. J, Lanas A. Systematic review update of observational studies further supports aspirin role in cancer treatment: Time to share evidence and decision-making with patients?

BACKGROUND

Evidence is growing that low-dose aspirin used as an adjuvant treatment of cancer is associated with an increased survival and a reduction in metastatic spread. We therefore extended up to August 2017 an earlier systematic search and meta-analyses of published studies of low-dose aspirin taken by patients with a diagnosis of cancer.

METHODS

Searches were completed in Medline and Embase to August 2017 using a pre-defined search strategy to identify reports of relevant studies. References in all the selected papers were scanned. Two reviewers independently applied pre-determined eligibility criteria and extracted data on cause-specific cancer deaths, overall mortality and the occurrence of metastatic spread. Meta-analyses were then conducted for different cancers and heterogeneity and publication bias assessed. Sensitivity analyses and attempts to reduce heterogeneity were conducted.

RESULTS

Analyses of 29 studies reported since an earlier review up to April 2015 are presented in this report, and these are then pooled with the 42 studies in our earlier publication. Overall meta-analyses of the 71 studies are presented, based on a total of over 120 thousand patients taking aspirin. Ten of the studies also give evidence on the incidence of metastatic cancer spread. There are now twenty-nine observational studies describing colorectal cancer (CRC) and post-diagnostic aspirin. Pooling the estimates of reduction by aspirin which are reported as hazard ratios (HR), gives an overall HR for aspirin and CRC mortality 0.72 (95% CI 0.64-0.80). Fourteen observational studies have reported on aspirin and breast cancer mortality and pooling those that report the association with aspirin as a hazard ratio gives HR 0.69 (0.53-0.90). Sixteen studies report on aspirin and prostate cancer mortality and a pooled estimate yields an HR of 0.87 (95% CI 0.73-1.05). Data from 12 reports relating to other cancers are also listed. Ten studies give evidence of a reduction in metastatic spread; four give a pooled HR 0.31 (95% CI 0.18, 0.54) and five studies which reported odds ratio of metastatic spread give OR 0.79 (0.66 to 0.95).

CONCLUSION

Being almost entirely from observational studies, the evidence of benefit from aspirin is limited. There is heterogeneity between studies and the results are subject to important biases, only some of which can be identified. Nevertheless, the evidence would seem to merit wide discussion regarding whether or not it is adequate to justify the recommendation of low-dose therapeutic aspirin, and if it is, for which cancers?