Serious Bleeding in Patients With Atrial Fibrillation Using Diltiazem With Apixaban or Rivaroxaban.

Importance: Diltiazem, a commonly prescribed ventricular rate-control medication for patients with atrial fibrillation, inhibits apixaban and rivaroxaban elimination, possibly causing overanticoagulation. Objective: To compare serious bleeding risk for new users of apixaban or rivaroxaban with atrial fibrillation treated with diltiazem or metoprolol. Design, Setting, and Participants: This retrospective cohort study included Medicare beneficiaries aged 65 years or older with atrial fibrillation who initiated apixaban or rivaroxaban use and also began treatment with diltiazem or metoprolol between January 1, 2012, and November 29, 2020. Patients were followed up to 365 days through November 30, 2020. Data were analyzed from August 2023 to February 2024. Exposures: Diltiazem and metoprolol. Main Outcomes and Measures: The primary outcome was a composite of bleeding-related hospitalization and death with recent evidence of bleeding. Secondary outcomes were ischemic stroke or systemic embolism, major ischemic or hemorrhagic events (ischemic stroke, systemic embolism, intracranial or fatal extracranial bleeding, or death with recent evidence of bleeding), and death without recent evidence of bleeding. Hazard ratios (HRs) and rate differences (RDs) were adjusted for covariate differences with overlap weighting. Results: The study included 204 155 US Medicare beneficiaries, of whom 53 275 received diltiazem and 150 880 received metoprolol. Study patients (mean [SD] age, 76.9 [7.0] years; 52.7% female) had 90 927 person-years (PY) of follow-up (median, 120 [IQR, 59-281] days). Patients receiving diltiazem treatment had increased risk for the primary outcome (RD, 10.6 [95% CI, 7.0-14.2] per 1000 PY; HR, 1.21 [95% CI, 1.13-1.29]) and its components of bleeding-related hospitalization (RD, 8.2 [95% CI, 5.1-11.4] per 1000 PY; HR, 1.22 [95% CI, 1.13-1.31]) and death with recent evidence of bleeding (RD, 2.4 [95% CI, 0.6-4.2] per 1000 PY; HR, 1.19 [95% CI, 1.05-1.34]) compared with patients receiving metoprolol. Risk for the primary outcome with initial diltiazem doses exceeding 120 mg/d (RD, 15.1 [95% CI, 10.2-20.1] per 1000 PY; HR, 1.29 [95% CI, 1.19-1.39]) was greater than that for lower doses (RD, 6.7 [95% CI, 2.0-11.4] per 1000 PY; HR, 1.13 [95% CI, 1.04-1.24]). For doses exceeding 120 mg/d, the risk of major ischemic or hemorrhagic events was increased (HR, 1.14 [95% CI, 1.02-1.27]). Neither dose group had significant changes in the risk for ischemic stroke or systemic embolism or death without recent evidence of bleeding. When patients receiving high- and low-dose diltiazem treatment were directly compared, the HR for the primary outcome was 1.14 (95% CI, 1.02-1.26). Conclusions and Relevance: In Medicare patients with atrial fibrillation receiving apixaban or rivaroxaban, diltiazem was associated with greater risk of serious bleeding than metoprolol, particularly for diltiazem doses exceeding 120 mg/d.

Fabry disease with early-onset ventricular dilation: A case report.

RATIONALE: The most common cardiac involvement of Fabry disease (FD) is left ventricular hypertrophy (LVH), which usually occurs in male patients over the age of 30. In rare cases, it can progress to ventricular dilation in the late stage of the disease. PATIENT CONCERNS: A 16-year-old boy presenting with recurrent extremity pain and chest distress was admitted to our hospital. Imaging examinations revealed ventricular dilation. DIAGNOSIS: α-Galactosidase A enzyme assay and GLA gene sequencing confirmed the diagnosis of FD and revealed a novel mutation c.76_77insT. INTERVENTIONS: The patient was treated using metoprolol (23.75 mg qd) and angiotensin-converting enzyme inhibitor (fosinopril sodium 5 mg qd). He refused enzyme replacement therapy for financial reasons. OUTCOMES: The echocardiography, electrocardiography, renal function, and routine blood and urine tests performed 20 months after the patients discharge from hospital showed no significant changes. The patient reported a slow and gradual decrease in the frequency and degree of pain and chest distress, starting approximately 24 months after discharge. LESSONS: Cardiac involvement of FD can progress rapidly in some cases. Screening for FD should be considered in patients with unexplained ventricular dilation, especially in those with a history of typical FD manifestations.

The effect of metoprolol and aspirin on cardiovascular risk in bereavement: A randomized controlled trial.

BACKGROUND: Bereavement is associated with an increased risk of cardiovascular disease; however, no reports exist of interventions to reduce risk. In a randomized, double-blind, placebo-controlled trial of 85 recently bereaved participants, we determined whether ß-blocker (metoprolol 25 mg) and aspirin (100 mg) reduce cardiovascular risk markers and anxiety, without adversely affecting bereavement intensity. METHODS: Participants were spouses (n = 73) or parents (n = 12) of deceased from 5 hospitals in Sydney, Australia, 55 females, 30 males, aged 66.1 ±â€¯9.4 years. After assessment within 2 weeks of bereavement, subjects were randomized to 6 weeks of daily treatment or placebo, and the effect evaluated using ANCOVA, adjusted for baseline values (primary analysis). RESULTS: Participants on metoprolol and aspirin had lower levels of home systolic pressure (P = .03), 24-hour average heart rate (P < .001) and anxiety (P = .01) platelet response to arachidonic acid (P < .001) and depression symptoms (P = .046) than placebo with no difference in standard deviation of NN intervals index (SDNNi), von Willebrand Factor antigen, platelet-granulocyte aggregates or bereavement intensity. No significant adverse safety impact was observed. CONCLUSIONS: In early bereavement, low dose metoprolol and aspirin for 6 weeks reduces physiological and psychological surrogate measures of cardiovascular risk. Although further research is needed, results suggest a potential preventive benefit of this approach during heightened cardiovascular risk associated with early bereavement.

Quality of life improves in vasovagal syncope patients after clinical trial enrollment regardless of fainting in follow-up.

BACKGROUND: Frequent syncope is linked to poorer health-related quality of life (HRQoL). Recurrent syncope has been observed to reduce in all groups after seeing a syncope expert and enrolling in a clinical trial. It is unknown if HRQoL improves with this reduction in syncope recurrence. OBJECTIVES: We examined the change in HRQoL over time in vasovagal syncope (VVS) patients seen by a syncope expert and enrolled in a trial. We also explored whether change differed with treatment or the frequency of fainting during follow up. METHODS: The Short Form Health Survey (SF36) was completed at baseline (BL), 6 m, and 12 m post-enrollment by VVS patients in the 1st and 2nd Prevention of Syncope Trials, which were multi-centered, randomized, placebo-controlled trials of metoprolol (POST) and fludrocortisone (POST2). Differences in HRQoL at BL, 6 m, and 12 m were analyzed and compared by faints in follow-up and randomization group. RESULTS: Complete study data were available for 143 VVS patients (40 ±â€¯17 years, 62% F). Over 12 months, patients reported improvement in all SF36 dimensions except for bodily pain. Post hoc analyses indicated that differences first occurred between BL and 6 m for all but general health. Fainting in follow-up or drug randomization group did not diminish the improvements. The baseline syncope burden was not different whether patients' HRQoL improved or not. CONCLUSION: HRQoL of VVS patients improves over time after enrolling in a clinical trial, even with recurrent faints or randomization to placebo. Improvements may result from alternative factors, such as interaction with experts or patient adjustment.

Comparing PyroMark Q24 Pyrosequencing and MALDI-TOF MS for Identification of CYP2D6*10.

BACKGROUND: CYP2D6*10 is mainly responsible for the large pharmacokinetic variability of routinely administered metoprolol in middle-aged and elderly Asian patients. Utilizing an efficient method for identifying the CYP2D6*10 genotypes is clinically important for evaluating the pharmacokinetic effect of administration of metoprolol. This study attempted to evaluate the effectiveness of the two methods used to detect the rs1065852 and rs1135840 SNPs of the CYP2D6*10 gene. METHODS: Blood samples were processed for the collection of genomic DNA from 198 subjects across Chinese population, and detection of CYP2D6*10 (rs1065852 and rs1135840) was performed using the PyroMark Q24 pyrose-quencing and matrix-assisted laser desorption/ionization time-of-flight mass-spectrometry (MALDI-TOF MS). The discordant results were further validated with Sanger sequencing. We eventually attempted to assess some features of these two methods including reliability, rapidness, being appropriate, and cost-effectiveness. RESULTS: Genotyping of rs1065852 and rs1135840 detected by MALDI-TOF MS were concordant with those identified by PyroMark Q24 pyrosequencing in all 198 (100%) individuals. The hands-on-time and the turnaround time were shorter in the PyroMark Q24 pyrosequencing method than in the MALDI-TOF MS method for SNP of CYP2D6*10. In terms of being cost-effective and high-throughput, the MALDI-TOF MS method outperformed the PyroMark Q24 pyrosequencing method. CONCLUSIONS: CYP2D6*10 genotypes detected by PyroMark Q24 pyrosequencing and MALDI-TOF-MS showed that both methods were reliable, rapid, appropriate, and cost-effective methods. These methods are valuable for clinical applications.

Low Utilization of Beta-Blockers Among Medicare Beneficiaries Hospitalized for Heart Failure With Reduced Ejection Fraction.

BACKGROUND: The evidence-based beta-blockers carvedilol, bisoprolol, and metoprolol succinate reduce mortality and hospitalizations among patients with heart failure with reduced ejection fraction (HFrEF). Use of these medications is not well described in the general population of patients with HFrEF, especially among patients with potential contraindications. OBJECTIVES: Our goal was to describe the patterns of prescription fills for carvedilol, bisoprolol, and metoprolol succinate among Medicare beneficiaries hospitalized for HFrEF, as well as to estimate the associations between specific contraindications for beta-blocker therapy and those patterns. METHODS AND RESULTS: With the use of the cohort of 15,205 Medicare beneficiaries hospitalized for HFrEF from 2007 to 2013 in the 5% Medicare random sample, we described prescription fills (30 days after discharge) and dosage patterns (1 year after discharge) for beta-blockers. By means of of Fine and Gray competing risk models, we estimated the associations between potential contraindications (hypotension, chronic obstructive pulmonary disease [COPD], asthma, and syncope) and prescription fill and dosing patterns while adjusting for demographics, comorbidities, and health care utilization. For beneficiaries who did not die or readmitted to the hospital, 38% of hospitalizations were followed by a prescription fill for an evidence-based beta-blocker within 30 days, 12% were followed by prescription fills for at least 50% of the recommended dose of an evidence-based beta-blocker within 1 year, and 9% were followed by a prescription fill for an up-titrated dose of an evidence-based beta-blocker within 1 year. The prevalence of the contraindications were 21% for hypotension, 48% for COPD, 15% for asthma, and 12% for syncope. Among beneficiaries who did not fill a prescription for an evidence-based beta-blocker within 30 days, 67% had at least 1 of these contraindications. Hypotension, COPD, and syncope were each associated with a ∼10% lower risk of filling a prescription for an evidence-based beta-blocker. CONCLUSIONS: Prescription fill and up-titration rates for evidence-based beta-blockers are low among Medicare beneficiaries with HFrEF, but contraindications explain only a minor part of these low rates.

Cost-effectiveness of nitrendipine and hydrochlorothiazide or metoprolol to treat hypertension in rural community health centers in China.

OBJECTIVES: The objective of this article is to compare blood pressure (BP)-lowing effects of nitrendipine and hydrochlorothiazide and nitrendipine and metoprolol, and estimate the economic effect of these therapies on hypertension. METHODS: Outpatients (N = 793) 18-70 years of age with stage 2 or severe hypertension (SBP ≥ 160 mmHg and/or DBP ≥ 100 mmHg) were recruited from four randomly selected rural community health centers in Beijing and Jilin. After drug wash out, they were randomly divided into nitrendipine and hydrochlorothiazide group or nitrendipine and metoprolol group. The costs of drug treatment for hypertension were calculated and general estimation, whereas effectiveness was measured as a reduction in SBP and DBP at the end of a 24-week study period. RESULTS: Overall, 623 patients were eligible for the study and after a 24-week follow-up, SBP and DBP were 131.2/82.2 mmHg for the nitrendipine and hydrochlorothiazide group and 131.4/82.9 mmHg for the nitrendipine and metoprolol group and these were not significantly different (P = 0.7974 SBP and P = 0.1166 DBP). Comparing with nitrendipine and metoprolol, the cost of nitrendipine and hydrochlorothiazide was less, and its effectiveness was similar. The cost/effect ratio (US$/mmHg) was 1.4 for SBP and 2.8 for DBP for the nitrendipine and hydrochlorothiazide group, and 1.9 and 3.8 for the nitrendipine and metoprolol group's SBP and DBP values, respectively. The incremental cost per patient for achieving target BP was 5.1. Adverse events were mild or moderate and there were no differences between treatment groups. CONCLUSION: Treating hypertension with nitrendipine and hydrochlorothiazide was cost-effective than nitrendipine and metoprolol, and these data will allow more reasonable and efficient allocation of limited resources in low-income countries.

[Comparative Assessment of Antianginal Efficacy and Safety of Nicorandil at the Background of Therapy With -Adrenoblockers in Ischemic Heart Disease Patients With Stable Angina].

AIM: to demonstrate impact of addition of nicorandil to standard treatment in patients with stable ischemic heart disease (IHD) on clinical manifestations of the disease and safety of conducted therapy. MATERIAL AND METHODS: We included in this double-blind placebo controlled study with parallel groups 120 patients with verified IHD and stable effort angina. During the entire study all patients received metoprolol (100 mg/day). Patients of main group were given nicorandil (10 mg twice a day for 2 weeks and 20 mg twice a day thereafter); patients of control group were given placebo. Study duration was 6 weeks. RESULTS: Addition of nicorandil was associated with significant reduction of number of anginal attacks both compared with control period and addition of placebo. Consumption of short acting nitrates significantly decreased on both nicorandil doses compared with control period. Adverse events were registered in 10 of 61 and 7 of 59 patients (16.4 and 11.9%) taking nicorandil and placebo, respectively (n.s.). Three patients withdrew from the study because of headache. CONCLUSION: Addition of nicorandil to standard therapy in patients with chronic IHD and stable effort angina promoted significant reduction of number of angina attacks. Good tolerability of nicorandil was also demonstrated.

[Regulatory Adaptive Status in Assessment of Efficacy of Pharmacotherapy and Prognostication of Complications in Functional Class III Chronic Heart Failure].

OBJECTIVE: to elucidate significance of regulatory adaptive status (RAS) for assessment of effectiveness of medical treatment and prediction of cardiovascular complications in functional class (FC) III congestive heart failure (CHF). MATERIAL AND METHODS: We included into this study 100 patients with hypertensive disease (HD) or ischemic heart disease (IHD) and FC III CHF with compromised systolic left ventricular (LV) function. All patients were randomized into two groups. In addition to complex background therapy (quinapril, torasemide, spironolactone) patients of group 1 (n=56, age 57.5+/-21.7 years) were given metoprolol succinate (59.1+/-12.1 mg/day) and patients of group 2 (n=44, age 57.1+/-21.4 years) - ivabradine (12.1+/-4.6 mg/day). Examination at baseline and after 6 months included cardiorespiratory synchronism test (in order to quantitatively define RAS), echocardiography, treadmill test, six minute walk test. Cardiovascular complications (CVC) were registered during 12 months of study treatment. RESULTS: Both schemes of complex therapy equally improved structural and functional state of the myocardium, increased tolerance to physical exercise, reduced neurohumoral hyperactivation. Positive impact on RAS was more pronounced in ivabradine group. Clinical efficacy of therapy as well as number of hospitalizations because of CHF decompensation, ischemic strokes, and cardiovascular deaths did not differ substantially between groups. Initially low or unsatisfactory RAS was associated with higher incidence of CVC while initial unsatisfactory RAS was associated with elevated risk of sudden death. CONCLUSION: The data obtained reflect independent value of determination of RAS for assessment of efficacy of pharmacotherapy and prognosis of CVC in patients with FCIII CHF.

Cost-effectiveness analysis of nebivolol and metoprolol in essential hypertension: a pharmacoeconomic comparison of antihypertensive efficacy of beta blockers.

OBJECTIVE: To estimate and compare the cost-effectiveness and safety of nebivolol with sustained-release metoprolol in reducing blood pressure by 1 mm of Hg per day in hypertensive patients. MATERIALS AND METHODS: This was a prospective, randomized, open label, observational analysis of cost-effectiveness, in a questionnaire-based fashion to compare the cost of nebivolol (2.5 mg, 5 mg, 10 mg) and sustained released metoprolol succinate (25 mg, 50 mg, 100 mg) in hypertensive patients using either of the two drugs. A total of 60 newly detected drug naïve hypertensive patients were considered for the comparison, of which 30 patients were prescribed nebivolol and the other 30 were prescribed metoprolol succinate as per the recommended dosage. Based on the data, statistical analysis was carried out using GraphPad Prism 5 and MS Excel Spreadsheet 2007. RESULT: The cost of reducing 1 mm of Hg blood pressure per day with nebivolol was 0.60, 0.70, and 1.06 INR, whereas that of metoprolol succinate was 0.93, 1.18, and 1.25 INR at their respective equivalent doses, hence significantly lower with the nebivolol group as compared to the metoprolol group (P < 0.05). CONCLUSION: This pharmacoeconomic analysis shows that nebivolol is more cost-effective as compared to metoprolol when the cost per reduction in blood pressure per day is considered. This may affect the patients economically during their long-term use of these molecules for the treatment of hypertension.

Health and cost benefits associated with the use of metoprolol in heart attack patients.

Heart attack (myocardial infarction) is a highly prevalent entity worldwide. Widespread implementation of reperfusion strategies has dramatically reduced the mortality associated with infarction. Paradoxically, the mortality reduction has significantly increased the incidence of chronic heart failure (HF). Treatment of HF, once present, represents a huge socioeconomic burden on individuals and healthcare systems. The possibility of preventing rather than treating post-infarction HF would be of paramount importance. Given that infarct size is the main determinant of adverse post-infarction outcomes (including chronic HF), therapies able to reduce infarct size are needed. The single administration of intravenous metoprolol before reperfusion has been recently shown to reduce infarct size and reduce the cases of chronic HF in a proof-of-concept trial. If confirmed in larger trials, this low-cost therapy is expected to have a major health and socioeconomic impact.

Economic impact of switching from metoprolol to nebivolol for hypertension treatment: a retrospective database analysis.

OBJECTIVE: To estimate the real-world economic impact of switching hypertensive patients from metoprolol, a commonly prescribed, generic, non-vasodilatory ß1-blocker, to nebivolol, a branded-protected vasodilatory ß1-blocker. METHODS: Retrospective analysis with a pre-post study design was conducted using the MarketScan database (2007-2011). Hypertensive patients continuously treated with metoprolol for ≥6 months (pre-period) and then switched to nebivolol for ≥6 months (post-period) were identified. The index date for switching was defined as the first nebivolol dispensing date. Data were collected for the two 6-month periods pre- and post-switching. Monthly healthcare resource utilization and healthcare costs pre- and post-switching were calculated and compared using Wilcoxon test and paired t-test. Medical costs at different years were inflated to the 2011 dollar. RESULTS: In total, 2259 patients (mean age: 60 years; male: 52%; cardiovascular [CV] disease: 37%) met the selection criteria. Switching to nebivolol was associated with statistically significant reductions in the number of all-cause hospitalization (-33%; p < 0.01), CV-related hospitalizations (-60%; p < 0.01), and outpatient visits (-7%; p < 0.01). Monthly inpatient costs were reduced by $111 (p < 0.01), while monthly drug costs increased by $52 (p < 0.01). No statistically significant differences were found in overall costs and costs of outpatient or ER visits. Sensitivity analyses, conducted using various lengths of medication exposure, controlling for spill-over effect or excluding patients with compelling indications for metoprolol, all found some level of reduction in resource utilization and no significant difference in overall healthcare costs. CONCLUSIONS: This real-world study suggests that switching from metoprolol to nebivolol is associated with an increase in medication costs and significant reductions in hospitalizations and outpatient visits upon switching, resulting in an overall neutral effect on healthcare costs. These results may be interpreted with caution due to lack of a comparator group and confounding control caused by design and limitations inherent in insurance claims data.

The problem of controlling for imperfectly measured confounders on dissimilar populations: a database simulation study.

OBJECTIVE(S): Observational database research frequently relies on imperfect administrative markers to determine comorbid status, and it is difficult to infer to what extent the associated misclassification impacts validity in multivariable analyses. The effect that imperfect markers of disease will have on validity in situations in which researchers attempt to match populations that have strong baseline health differences is underemphasized as a limitation in some otherwise high-quality observational studies. The present simulations were designed as a quantitative demonstration of the importance of this common and underappreciated issue. DESIGN: Two groups of Monte Carlo simulations were performed. The first demonstrated the degree to which controlling for a series of imperfect markers of disease between different populations taking 2 hypothetically harmless drugs would lead to spurious associations between drug assignment and mortality. The second Monte Carlo simulation applied this principle to a recent study in the field of anesthesiology that purported to show increased perioperative mortality in patients taking metoprolol versus atenolol. SETTING/PARTICIPANTS/INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Simulation 1: High type-1 error (ie, false positive findings of an independent association between drug assignment and mortality) was observed as sensitivity and specificity declined and as systematic differences in disease prevalence increased. Simulation 2: Propensity score matching across several imperfect markers was unlikely to eliminate important baseline health disparities in the referenced study. CONCLUSIONS: In situations in which large baseline health disparities exist between populations, matching on imperfect markers of disease may result in strong bias away from the null hypothesis.

Prevention of perioperative atrial fibrillation with betablockers in coronary surgery: betaxolol versus metoprolol.

In this study, we tried to compare the efficacy and safety of betaxolol vs. metoprolol immediately postoperatively in coronary artery bypass grafting (CABG) patients and to determine whether prophylaxy for atrial fibrillation (AF) with betaxolol could reduce hospitalization and economic costs after cardiac surgery. Our trial was open-label, randomized, multicentric enrolling 1352 coronary surgery patients randomized to receive betaxolol or metoprolol. The primary endpoints were the composites of 30-day mortality, in-hospital AF (safety endpoints), duration of hospitalization and immobilization, quality of life, and the above endpoint plus in-hospital embolic event, bradycardia, gastrointestinal symptoms, sleep disturbances, cold extremities (efficacy plus safety endpoint). At the end of the study the incidence and probability of early postoperative AF with betaxolol was lower than with metoprolol in coronary surgery (P<0.0001). In the two study groups minor side effects were similar and no major complication was reported (P<0.001). Patient compliance was good and the general condition improved due to shortened hospitalization and immobilization with subsequent improvement in the psychological status, less arrhythmias and lack of significant side effects. In conclusion, because of its efficacy and safety, betaxolol was superior to metoprolol for the prevention of the early postoperative AF in coronary surgery.

Lack of association between adrenergic receptor genotypes and survival in heart failure patients treated with carvedilol or metoprolol.

OBJECTIVES: This study investigated the role of adrenergic receptor genetics on transplant-free survival in heart failure (HF). BACKGROUND: Discordant results exist for genetic associations between adrenergic receptor alleles and end points of beta-blocker response in HF patients. METHODS: We identified 637 patients enrolled in 2 U.S. cardiovascular genetic registries with HF and left ventricular systolic dysfunction who were discharged on beta-blocker, angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker (ARB), and diuretic medications. End points were determined through the national Social Security Death Master File and transplant records. We genotyped 5 polymorphisms in 3 genes: ADRB1 (S49G, R389G), ADRB2 (G16R, Q27E), and ADRA2C (Del322-325) using 5' nuclease assays and performed a multivariable clinical-genetic analysis. RESULTS: A total of 190 events (29.8%) occurred over a median follow-up of 1,070 days. Multivariable analysis showed a significant effect of 4 clinical factors on survival: age (p = 0.006), gender (p = 0.005), ejection fraction (p = 0.0002), and hemoglobin (p = 0.00010). There was no significant effect of the polymorphisms or haplotypes analyzed on survival. CONCLUSIONS: Genotypes and haplotypes of ADRB1, ADRB2, and ADRA2C did not significantly affect survival in metoprolol-treated or carvedilol-treated HF patients in this study. These results complement the findings of 2 similarly designed previous studies, but do not replicate an association of ADRB2 haplotypes and survival. All 3 studies differ from a survival benefit reported for bucindolol-treated homozygous ADRB1 R389 individuals. This may be attributable to a drug-specific interaction between genotype and outcome with bucindolol that does not seem to occur with metoprolol or carvedilol.

Hospitalization rates of generic metoprolol compared with the original beta-blocker in an epidemiological database study.

PURPOSE: A less favourable galenic profile of generic formulations of the beta-blocker metoprolol raised the concern of a higher risk for serious cardiovascular (CV) events. We assessed hospital admission rates for CV diseases and prescription prevalences of various drugs using claims data of statutory health insurances (SHIs) to compare the incidence of serious CV events among users of original and generic metoprolol. Index events included hospitalization due to myocardial infarction, hypertensive crisis and stroke. METHODS: Data files of three SHIs were linked with dispensing data of drug prescriptions from each pharmacy's electronic data processing centre on an individual basis. Incidences of hospital admissions among patients receiving original metoprolol and among patients treated with the generic equivalent were compared by logistic regression, stratified for Bremen and the rest of Northern Germany. Risk estimates and confidence intervals were adjusted for confounders. RESULTS: A total of 49,673 patients receiving metoprolol were identified within a cohort of 3,649,285 insurance members. While the crude analysis revealed a higher risk for index events in patients receiving the generic drug (Bremen: RR 1.45; Northern Germany: RR 1.14), no elevated risk remained after confounder adjustment (Bremen: OR 1.06; Northern Germany: OR 1.04). Among co-morbid conditions considered as confounders, a previous CV event and an elevated thromboembolic risk exerted the strongest effect on index events. CONCLUSIONS: SHI data are a valuable source for pharmacoepidemiology and health services research in Germany. Incidence rates of serious CV events did not reveal any noticeable differences between the original and the generic group after confounder adjustment.

[Assessment of dynamics of the autonomic cardiovascular system regulation based on low-frequency rhythm synchronization in patients with ischemic heart diseases complicated by myocardial infarction treated with metoprolol].

AIM: To develop a procedure for assessing the adequacy of metoprolol use in patients with coronary heart disease (CHD) on the basis of synchronization of 0.1-Hz rhythms in cardiac rhythm variability (CRV) and vascular blood filling in the microcirculatory bed (MCB). Materials and methods. 43 patients with CHD (age 63 +/- 8 years), who had sustained myocardial infarction about 6 months before, were examined. Synchronous registration of ECG and a pulsogram were made during an orthostatic test before and after therapy with metoprolol in the maximum tolerable doses during 3 months. The presence of synchronization of 0.1-Hz rhythms identified from a series of R-R intervals and the pulsogram was determined from the difference of phases; the total percent of synchronization (S) was estimated. RESULTS: The authors identified 2 groups of CHD patients: those with positive (n=21) and negative (n=16) orthostatic S, trends during treatment. The groups were matched by major clinical characteristics. There was an inverse relationship between the values of S, in the lying and standing position prior to or following treatment. It is suggested that there is the optimum range of 0.1-Hz rhythm synchronization values in the cardiovascular system during beta-blocker therapy in patients with CHD. CONCLUSION: There is a possibility applying an objective approach to assessing the adequacy of metoprolol treatment in CHD patients on the basis of synchronization of 0.1-Hz fluctuations in variations CR V and vascular blood filling in MCB.