Use of proton pump inhibitors and the risk of coronary events in new users of low-dose acetylsalicylic acid in UK primary care

Aspirin Resistance: Cardiovascular Risk Game Changer

BACKGROUND

Aspirin (ASA) is the most used medication on the globe. ASA is a primary pillar of the secondary prevention of cardiovascular atherothromboembolic events. However, a fraction of the population does not respond to ASA as expected in a unique phenomenon called ASA resistance. Multiple mechanisms were described and studied in the literature to explain this phenomenon.

AREA OF UNCERTAINTY

ASA resistance is an interesting phenomenon that is worth studying and reviewing. Mechanisms behind this resistance are various and although the rarity of some, it is crucial for the modern health provider to be aware of such phenomenon and its possible explanations to provide more efficient preventive cardiology practice. Our study aimed to review and conclude the evidence behind ASA resistance and its implication on the cardiovascular health.

DATA SOURCES

We searched databases like PubMed, EMBASE, Ovid by midline, and Google Scholar for published articles and abstracts.

RESULTS

Our systemic search revealed more than 100 articles in relation to ASA resistance. We selected 40 articles, which were relevant for this review. Various mechanisms were described in the literature, with few of them very well documented and understood. Main mechanisms include medication nonadherence, interaction with proton pump inhibitors, esterase-mediated ASA inactivation, post-coronary artery bypass grafting (CABG) MRP-4-mediated ASA consumption, cyclooxygenase-1 (COX-1) polymorphisms, high platelet turnover-associated regeneration of platelet COX-1, and the documented platelet ability of de novo COX-1 synthesis in response to thrombin and fibrinogen.

CONCLUSION

Multiple mechanisms of ASA resistance were described in the literature. Awareness of such interaction is important for medical practitioners. Bottom line, further studies and reviews are needed to further study this phenomenon and its implication on the cardiovascular health and hence reaching a valid evidence-based conclusion that might change the practice and improve the patient preventive health care.

Proton Pump Inhibitors in Cardiovascular Disease: Drug Interactions with Antiplatelet Drugs

Aspirin and P2Y₁₂ receptor antagonists are widely used across the spectrum of cardiovascular diseases. Upper gastrointestinal complications, including ulcer and bleeding, are relatively common during antiplatelet treatment and, therefore, concomitant proton pump inhibitor (PPI) treatment is often prescribed.PPIs provide gastroprotection by changing the intragastric milieu, essentially by raising intragastric pH. In recent years, it has been heavily discussed whether PPIs may reduce the cardiovascular protection by aspirin and, even more so, clopidogrel. Pharmacodynamic and pharmacokinetic studies suggested an interaction between PPIs and clopidogrel, and subsequent clinical studies were conducted to evaluate the clinical impact of this interaction. More recently, it was reported that PPIs may also attenuate the antiplatelet effect of aspirin. This may be clinically important, because a fixed combination of aspirin and a PPI (esomeprazole) has recently been approved and because aspirin is the most widely used drug in patients with cardiovascular disease. The antiplatelet effect of the new P2Y₁₂ receptor antagonists, ticagrelor and prasugrel, seems less influenced by PPI co-treatment.Given the large number of patients treated with antithrombotic drugs and PPIs, even a minor reduction of platelet inhibition potentially carries considerable clinical impact. The present book chapter summarizes the evidence regarding the widespread use of platelet inhibitors and PPIs in combination. Moreover, it outlines current evidence supporting or opposing drug interactions between these drugs and discusses clinical implications.

Comparison of Intravenous plus Oral Pantoprazole Therapy and Oral Pantoprazole Alone for Preventing Gastrointestinal Bleeding in Acute Coronary Syndrome Patients with High Bleeding Risk

BACKGROUND

It is unclear whether intravenous proton pump inhibition is more effective than oral administration in preventing gastrointestinal (GI) bleeding in high bleeding risk patients with acute coronary syndromes (ACS).

METHODS AND RESULTS

A total of 504 patients with ACS and high bleeding risk were randomly assigned into two groups. Study group (n=252) received intravenous pantoprazole for five days and subsequent oral pantoprazole for 12 months. Control group (n=252) received oral pantoprazole for 12 months. Major adverse cardiac events (death, re-infarction, re-revascularisation and stroke) and GI bleeding were registered after a follow-up of 12 months. No statistically significant differences were found in the major adverse cardiac events between the two groups after the follow-up (p >0.05). The incidence of major GI bleeding in the study group was lower than in the control group (1.2% vs. 3.9%, p=0.049). The bleeding rates in the first 30 days in the study group were also lower than in the control group (0.3% vs. 2.7%, p=0.032).

CONCLUSIONS

The main outcome of cardiac events did not differ between the treatment groups. Intravenous plus oral pantoprazole therapy seemed more effective than oral therapy alone in the prevention of GI bleeding in high bleeding risk patients with ACS.

Influence of proton pump inhibitors and VKORC1 mutations on CYP2C9-mediated dose requirements of vitamin K antagonist therapy: a pilot study

Interindividual variations in dose requirements of oral vitamin K antagonists (VKA) are attributed to several factors, including genetic variant alleles of vitamin K epoxide reductase complex subunit 1 (VKORC1) and cytochrome P450 2C9 (CYP2C9), but also interaction with co-medications. In this context, proton pump inhibitor (PPI)-related alterations of VKA maintenance dose requirements have been published. The present investigation aimed to test for an interaction profile of oral VKA-therapy and PPIs in relation to the CYP2C9 genotype. Median weekly stable VKA dose requirements over 1 year were recorded in 69 patients. Patients were genotyped for CYP2C9*2, CYP2C9*3, VKORC1c.-1639G>A and VKORC1c.174-136C>T and assessed for an association with PPI use and total VKA maintenance dose requirements. PPI users with CYP2C9 genetic variations required significantly lower weekly VKA maintenance doses than those with the wild-type genotype (t-test: P = 0·02). In contrast, in subjects without PPI use, the CYP2C9 genotype had no significant influence on oral VKA dose requirements. Further, the combined CYP2C9/VKORC1 genotype was a significant predictor for VKA dose requirements [linear regression: estimate: -1·47, standard error: 0·58 (P = 0·01)]. In conclusion, in carriers of CYP2C9 gene variations, the interference with the VKA metabolism is modified by PPI co-medication and the VCKORC1 genotype. Preceding knowledge of the genetic profile and the awareness for potentially occurring severe over-anticoagulation problems under PPI co-medication could contribute to a safer and personalized VKA pharmacotherapy.

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

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