Class effect of beta-blockers in survivors of ST-elevation myocardial infarction: A nationwide cohort study using an insurance claims database

Stability-Indicating Liquid Chromatographic Method Development for the Simultaneous Determination of Amitriptyline Hydrochloride and Propranolol Hydrochloride in Tablet Dosage Form

The combination of the tricyclic antidepressant amitriptyline hydrochloride (AMH) and the non-selective beta-adrenergic blocker propranolol hydrochloride (PPH) is used for migraine prophylaxis. Higher doses of AMH trigger cardiac arrhythmias, anxiety, tachycardia, convulsions, hyperglycemia and anticholinergic side effects. The combined dosage formulation of AMH and PPH leads to drug-drug interactions; causes sedation, xerostomia, dysuria, insomnia and bradycardia; and results in patient non-compliance. The quantification of AMH and PPN becomes essential, especially for combination formulations, in addition to regular quality control to avoid clinical issues. Considering these facts into account, the reverse-phase -high-performance liquid chromatography (RP-HPLC) method was developed in accordance with International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use Q2(R1) guidelines for the simultaneous determination of AMH and PPH. The HPLC separation was performed on an HPLC system (Shimadzu, Japan, Prominence I series 2030C) using a Shimadzu Shim-Pack GIST C18 column (100 mm × 4.6 mm, 5 μ), which was equipped with an ultraviolet detector at the isosbestic point 238 nm. The mixture of acetonitrile and orthophosphoric acid (pH 3.5) in a ratio of 35:65 v/v with a flow rate of 0.75 mL/min was used as the mobile phase. The regression coefficients of AMH (r2 > 0.998) and PPH (r2 > 0.999) show good linearity between peak areas and drug concentration ranges. The limits of detection (AMH = 0.67 μg/mL, PPH = 0.67 μg/mL) and limits of quantification (AMH = 2.04 μg/mL, PPH = 2.05 μg/mL) demonstrated the higher detection sensitivity of the proposed method.

Long-Term Effect of Non-Selective Beta-Blockers in Patients With Rheumatoid Arthritis After Myocardial Infarction-A Nationwide Cohort Study

Objectives: Rheumatoid arthritis (RA) is an independent nontraditional risk factor for incidence of myocardial infarction (MI) and post-MI outcome is impaired in the RA population. Use of beta-blockers improves the long-term survival after MI in the general population while the protective effect of beta-blockers in RA patients is not clear. We investigate the impact of beta-blockers on the long-term outcome of MI among RA patients.

Methods: We identified RA subjects from the registries for catastrophic illness and myocardial infarction from 2003 to 2013. The enrolled subjects were divided into three groups according to the prescription of beta-blockers (non-user, non-selective, and β1-selective beta-blockers). The primary endpoint was all-cause mortality. We adjusted clinical variables and utilized propensity scores to balance confounding bias. Cox proportional hazards regression models were used to estimate the incidence of mortality in different groups.

Results: A total of 1,292 RA patients with myocardial infarction were enrolled, where 424 (32.8%), 281 (21.7%), and 587 (45.5%) subjects used non-user, non-selective, and β1-selective beta-blockers, respectively. Use of beta-blockers was associated with lower risk of all-cause mortality after adjustment with comorbidities, medications (adjusted hazard ratio [HR] 0.871; 95% confidence interval [CI] 0.727–0.978), and propensity score (HR 0.882; 95% CI 0.724–0.982). Compared with β1-selective beta-blockers, treatment with non-selective beta-blockers (HR 0.856; 95% CI 0.702–0.984) was significantly related to lower risk of mortality. The protective effect of non-selective beta-blockers remained in different subgroups including sex and different anti-inflammatory drugs.

Conclusion: Use of beta-blockers improved prognosis in post-MI patients with RA. Treatment with non-selective beta-blockers was significantly associated with reduced risk of mortality in RA patients after MI rather than β1-selective beta-blockers.

Pre- and Post-Conditioning of the Heart: An Overview of Cardioprotective Signaling Pathways

Since the discovery of ischemic pre- and post-conditioning, more than 30 years ago, the knowledge about the mechanisms and signaling pathways involved in these processes has significantly increased. In clinical practice, on the other hand, such advancement has yet to be seen. This article provides an overview of ischemic pre-, post-, remote, and pharmacological conditioning related to the heart. In addition, we reviewed the cardioprotective signaling pathways and therapeutic agents involved in the above-mentioned processes, aiming to provide a comprehensive evaluation of the advancements in the field. The advancements made over the last decades cannot be ignored and with the exponential growth in techniques and applications. The future of pre- and post-conditioning is promising.

Selection of β-Blocker in Patients With Cirrhosis and Acute Myocardial Infarction: A 13-Year Nationwide Population-Based Study in Asia

Background It is not clear whether β₁-selective or nonselective β-blockers should be used in patients with cirrhosis and acute myocardial infarction. Methods and Results Medical records were retrieved from Taiwan NHIRD (National Health Insurance Research Database) during 2001-2013. Patients were excluded for age <20, previous acute myocardial infarction, contraindication to β-blockers, chronic obstructive pulmonary disease, asthma, or atrioventricular conduction disease. Patients who died during index admission, had a follow-up <6 months, had a medication ratio of either β₁-selective or nonselective β-blocker <80%, or who switched between β-blockers were also excluded. Patients on β₁-selective blockers and nonselective β-blockers were propensity score matched and compared for outcome. Primary outcomes were 1- and 2-year cardiovascular events, liver adverse outcomes, and all-cause mortality. A total of 203 595 patients with acute myocardial infarction were enrolled, of whom 6355 had cirrhosis. After screening for exclusion criteria, 1769 patients (655 patients on β-blockers and 1114 patients not on β-blockers) were eligible for analysis. Among patients on β-blockers, propensity score matching was performed, and 218 patients on β₁-selective blockers and 218 patients on nonselective β-blockers were studied. During a 2-year follow-up, patients on β₁-selective blockers had significantly fewer major cardiac and cerebrovascular events (hazard ratio=0.62; 95% confidence interval=0.42-0.91; P=0.014), a trend toward lower all-cause mortality (hazard ratio=0.66; 95% confidence interval=0.38-1.14; P=0.135), and nonworsening liver outcome (hazard ratio=0.66; 95% confidence interval=0.38-1.14; P=0.354). Conclusions In patients with cirrhosis and acute myocardial infarction, selecting a β-blocker is a clinical dilemma. Our study showed that the use of β₁-selective blockers is associated with lower risks of major cardiac and cerebrovascular events.

Ontology-based systematical representation and drug class effect analysis of package insert-reported adverse events associated with cardiovascular drugs used in China

With increased usage of cardiovascular drugs (CVDs) for treating cardiovascular diseases, it is important to analyze CVD-associated adverse events (AEs). In this study, we systematically collected package insert-reported AEs associated with CVDs used in China, and developed and analyzed an Ontology of Cardiovascular Drug AEs (OCVDAE). Extending the Ontology of AEs (OAE) and NDF-RT, OCVDAE includes 194 CVDs, CVD ingredients, mechanisms of actions (MoAs), and CVD-associated 736 AEs. An AE-specific drug class effect is defined to exist when all the drugs (drug chemical ingredients or drug products) in a drug class are associated with an AE, which is formulated as a new proportional class level ratio (“PCR”) = 1. Our PCR-based heatmap analysis identified many class level drug effects on different AE classes such as behavioral and neurological AE and digestive system AE. Additional drug-AE correlation tests (i.e., class-level PRR, Chi-squared, and minimal case reports) were also modified and applied to further detect statistically significant drug class effects. Two drug ingredient classes and three CVD MoA classes were found to have statistically significant class effects on 13 AEs. For example, the CVD Active Transporter Interactions class (including reserpine, indapamide, digoxin, and deslanoside) has statistically significant class effect on anorexia and diarrhea AEs.

Comparative Effectiveness and Safety of Dabigatran and Rivaroxaban in Atrial Fibrillation Patients

Background

We aimed to examine the comparative effectiveness and safety between dabigatran and rivaroxaban in atrial fibrillation patients.

Methods and Results

We conducted a population‐based, retrospective, new‐user cohort study based on the National Health Insurance claims database in Taiwan. Adult atrial fibrillation patients who initiated dabigatran (N=10 625) or rivaroxaban (N=4609) between June 1, 2012 and May 31, 2014 were identified as the overall population. A propensity score was derived using logistic regression to model the probability of receipt of rivaroxaban as a function of potential confounders. Altogether, 4600 dabigatran users were matched with 4600 rivaroxaban users to create a propensity score–matched population. The marginal proportional hazards model was applied among the propensity score–matched population as the primary analysis, and the proportional hazards model with adjustment of the quintiles of the propensity score among the overall population was used as the secondary analysis. Rivaroxaban users had a higher risk of all‐cause death than dabigatran users (hazard ratio 1.44, 95%CI 1.17‐1.78 in the primary analysis and hazard ratio 1.47, 95%CI 1.23‐1.75 in the secondary analysis). Rivaroxaban users also possessed a higher risk of gastrointestinal hemorrhage needing transfusion than dabigatran users in the primary analysis (hazard ratio 1.41, 95%CI 1.02‐1.95), but the difference diminished in the secondary analysis (hazard ratio 1.20, 95%CI 0.92‐1.56). The risks of ischemic stroke, acute myocardial infarction, arterial embolism/thrombosis, and intracranial hemorrhage were similar between the 2 groups.

Conclusions

Rivaroxaban therapy was associated with a statistically significant increase in all‐cause death compared with dabigatran therapy in atrial fibrillation patients.

Cysteinyl Leukotriene Receptor Antagonists Decrease Cancer Risk in Asthma Patients

Previous in vitro and in vivo studies have demonstrated the potential of using cysteinyl leukotriene receptor antagonists (LTRAs) for chemoprevention, but this has not been investigated in any clinical setting. We therefore investigated the chemopreventive effect of LTRAs in a nationwide population-based study. From the Taiwan National Health Insurance Research Database, we enrolled adults with newly-diagnosed asthma between 2001 and 2011. Among these patients, each LTRA user was matched with five randomly-selected LTRA non-users by sex, age, asthma diagnostic year and modified Charlson Comorbidity Index score. We considered the development of cancer as the outcome. Totally, 4185 LTRA users and 20925 LTRA non-users were identified. LTRA users had a significantly lower cancer incidence rate than LTRA non-users did. Multivariable Cox regression analyses adjusting for baseline characteristics and comorbidities showed LTRA use was an independent protecting factor (hazard ratio = 0.31 [95% CI: 0.24–0.39]), and cancer risk decreased progressively with higher cumulative dose of LTRAs. In conclusion, this study revealed that the LTRA use decreased cancer risk in a dose-dependent manner in asthma patients. The chemopreventive effect of LTRAs deserves further study.