Use of antiarrhythmic drugs in elderly patients

Randomized Study Comparing Radiofrequency Ablation with the PVAC Gold System vs. Antiarrhythmic Drugs in Elderly Patients with Symptomatic Atrial Fibrillation

BACKGROUND

There are no randomized studies comparing the maintenance of sinus rhythm after catheter ablation (CA) concerning treatment with antiarrhythmic drugs (AA) in elderly patients with paroxysmal atrial fibrillation (AF).

OBJECTIVES

To compare the clinical results of pulmonary vein (PV) isolation with the second-generation PVAC Gold catheter against AA treatment in elderly people with recurrent symptomatic paroxysmal AF, refractory to at least one AA, and without structural heart disease.

METHODS

Sixty patients with paroxysmal AF ≥ 65 years old were randomized to two forms of treatment: group 1: CA and group 2: AA drugs. The primary outcome was the AF recurrence-free rate after at least one year of follow-up. Secondary outcomes were: progression to persistent forms of AF, impact on quality of life (QOLF), and complications. The significance level adopted in the statistical analysis was 5% (p<0.05).

RESULTS

The AF recurrence-free rate was 80% (10% with amiodarone) in the CA group, after 1.3 procedures per patient and 65% in the AA group (60% with amiodarone), (p = 0.119) in an average follow-up of 719 days (Q1: 566; Q3: 730). The persistent AF free rate was 83.4% in the AC group and 67.7% in the AA group (p = 0.073) Both strategies showed an improvement in the AFQoL score during follow-up (p < 0.001), with no difference between the groups. Although without clinical repercussions or impact on the intellectual assessment test, 25% of patients in the CA group showed signs of cerebral embolization on brain MRI.

CONCLUSIONS

Both strategies for maintaining sinus rhythm promoted an improvement in the quality of life of elderly patients with symptomatic AF, with no statistical difference in the clinical outcomes. Additional studies using technologies with a better safety profile are needed to evaluate the benefits of CA in elderly patients with AF.

Assessment of Dofetilide or Sotalol Tolerability in the Elderly

Background: Dofetilide and sotalol are potassium channel antagonists that require inpatient QTc monitoring during initiation, due to increased risk of fatal arrhythmias. Elderly patients are especially subject to an increased risk of fatal arrhythmias due to polypharmacy, comorbidities, and physiologic cardiac changes with aging. This study will describe the tolerability and risk factors associated with the initiation of sotalol or dofetilide in patients ≥80 years of age. Methodology: This is a multicenter, retrospective, descriptive study of patients ≥80 years old who were initiated on either dofetilide or sotalol between May 8, 2018 and July 31, 2021 at institutions within the Mayo Clinic Health System. The percentage of patients who received nonpackage insert recommended doses was identified. Incidence of and reasons for dose reductions or discontinuations due to safety-related events or clinical concerns during the initial loading period were collected. Results: The final analysis included 104 patients. The majority of patients (75%) received nonstandard initial doses of dofetilide or sotalol based on baseline estimated creatinine clearance or QTc. Overall, 39% (N = 41) of patients experienced a dose reduction or discontinuation due to a safety-related event or concern. Patients who received nonstandard initial doses of dofetilide or sotalol had 4.7 times greater odds of experiencing a safety-related event requiring dose reduction or discontinuation. Conclusion: Following package insert dosing in elderly patients increases safety and tolerability relative to more aggressive dosing of dofetilide or sotalol.

EHRA expert consensus document on the management of arrhythmias in frailty syndrome, endorsed by the Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), Latin America Heart Rhythm Society (LAHRS), and Cardiac Arrhythmia Society of Southern Africa (CASSA)

There is an increasing proportion of the general population surviving to old age with significant chronic disease, multi-morbidity, and disability. The prevalence of pre-frail state and frailty syndrome increases exponentially with advancing age and is associated with greater morbidity, disability, hospitalization, institutionalization, mortality, and health care resource use. Frailty represents a global problem, making early identification, evaluation, and treatment to prevent the cascade of events leading from functional decline to disability and death, one of the challenges of geriatric and general medicine. Cardiac arrhythmias are common in advancing age, chronic illness, and frailty and include a broad spectrum of rhythm and conduction abnormalities. However, no systematic studies or recommendations on the management of arrhythmias are available specifically for the elderly and frail population, and the uptake of many effective antiarrhythmic therapies in these patients remains the slowest. This European Heart Rhythm Association (EHRA) consensus document focuses on the biology of frailty, common comorbidities, and methods of assessing frailty, in respect to a specific issue of arrhythmias and conduction disease, provide evidence base advice on the management of arrhythmias in patients with frailty syndrome, and identifies knowledge gaps and directions for future research.

Efficacy Evaluation of the Mahuang-Fuzi-Xixin Decoction in Combination with Shenmai Injection for Bradyarrhythmia Treatment: A Systematic Review and Meta-Analysis

Background

Bradyarrhythmia treatment is often not timely enough, posing a potential threat to health. It is necessary to find a strategy with stable curative effects and high safety. Mahuang-Fuzi-Xixin (MFX) decoction and Shenmai injection (SMI) are compound Chinese Patent Medicines. Recent evidence has shown that the combined use of these two drugs can effectively treat bradyarrhythmia.

Purpose

To evaluate the effect of MFX decoction combined with SMI on bradyarrhythmia.

Methods

PRISMA was followed as the guideline for this systematic review. RevMan 5.4 software was applied for meta-analysis.

Results

Eight studies were included in the analysis, with a total of 340 patients in the intervention and control groups. The results of the meta-analysis showed that the effective rate of MFX combined with SMI treatment was higher than that of SMI alone (OR = 3.27, 95% CI (2.18, 4.89), P < 0.01); after treatment, MFX combined with SMI treatment and SMI alone had no significant difference in heart rate. In the subgroup of patients with an age less than 60, the effect of MFX combined with SMI treatment on the 24-hour mean heart rate was better than that of SMI alone (MD = 3.68, 95% CI (3.14, 4.22), P < 0.01), as did the 24-hour minimal heart rate (MD = 3.48, 95% CI (3.03, 3.93), P < 0.01). In addition, the effect of MFX combined with SMI treatment on the Traditional Chinese Medicine syndrome score (TCMSS) was significantly better than that of SMI alone (MD = -2.69, 95% CI (-3.10, -2.28), P < 0.01). In terms of safety, two adverse events were reported in the SMI combined with MFX group compared to 12 in the SMI alone group.

Conclusions

MFX combined with SMI treatment is effective in treating bradyarrhythmia. However, the results were heterogeneous. The safety of MFX combined with SMI treatment should be verified and treated with caution.

Aging-associated susceptibility to stress-induced ventricular arrhythmogenesis is attenuated by tetrodotoxin

Aging is associated with increased prevalence of life-threatening ventricular arrhythmias, but mechanisms underlying higher susceptibility to arrhythmogenesis and means to prevent such arrhythmias under stress are not fully defined. We aimed to define differences in aging-associated susceptibility to ventricular fibrillation (VF) induction between young and aged hearts. VF induction was attempted in isolated perfused hearts of young (6-month) and aged (24-month-old) male Fischer-344 rats by rapid pacing before and following isoproterenol (1 μM) or global ischemia and reperfusion (I/R) injury with or without pretreatment with low-dose tetrodotoxin, a late sodium current blocker. At baseline, VF could not be induced; however, the susceptibility to inducible VF after isoproterenol and spontaneous VF following I/R was 6-fold and 3-fold higher, respectively, in old hearts (P < 0.05). Old animals had longer epicardial monophasic action potential at 90% repolarization (APD₉₀; P < 0.05) and displayed a loss of isoproterenol-induced shortening of APD₉₀ present in the young. In isolated ventricular cardiomyocytes from older but not younger animals, 4-aminopyridine prolonged APD and induced early afterdepolarizations (EADs) and triggered activity with isoproterenol. Low-dose tetrodotoxin (0.5 μM) significantly shortened APD without altering action potential upstroke and prevented 4-aminopyridine-mediated APD prolongation, EADs, and triggered activity. Tetrodotoxin pretreatment prevented VF induction by pacing in isoproterenol-challenged hearts. Vulnerability to VF following I/R or catecholamine challenge is significantly increased in old hearts that display reduced repolarization reserve and increased propensity to EADs, triggered activity, and ventricular arrhythmogenesis that can be suppressed by low-dose tetrodotoxin, suggesting a role of slow sodium current in promoting arrhythmogenesis with aging.

Pharmacokinetic determinants for the right dose of antiarrhythmic drugs

INTRODUCTION

Antiarrhythmic drugs (AADs) show a narrow therapeutic range and marked intersubject variability in pharmacokinetics (PK), which may lead to inappropriate dosing and drug toxicity.

AREAS COVERED

The aim of the present review is to describe PK properties of AADs, discussing the main changes in different clinical scenarios, such as the elderly and patients with obese, chronic kidney, liver, and cardiac disease, in order to guide their right prescription in clinical practice.

EXPERT OPINION

There are few data about PK properties of AADs in a special population or challenging clinical setting. The use and dose of AADs is commonly based on physicians' clinical experience observing the clinical effects rather than being personalized on the individual patients PK profiles. More and updated studies are needed to validate a patient centered approach in the pharmacological treatment of arrhythmias based on patients' clinical features, including pharmacogenomics, and AAD pharmacokinetics.

Efficacy and Safety of Ablation for Symptomatic Atrial Fibrillation in Elderly Patients: A Meta-Analysis

Background: Age affects the efficacy of pharmacological treatment for atrial fibrillation (AF). Catheter ablation, including radiofrequency (RF) or cryoballoon ablation, is an effective strategy for symptomatic AF. This meta-analysis aimed to analyze the efficacy and safety of AF ablation in elderly patients with AF compared to non-elderly patients with AF. Methods: We searched several databases for articles published between January 1, 2008 and March 31, 2020. Eighteen observational studies with 21,039 patients were analyzed. Data including recurrence of AF or atrial tachyarrhythmia (ATA), complications, procedural time, and fluoroscopic time were compared between the elderly and non-elderly groups. Results: The elderly patients had significantly higher incidences of recurrent AF or ATA after AF ablation compared to the non-elderly patients (<60 years old) (odds ratio [OR], 1.21; 95% confidence interval [CI], 1.11-1.33). The elderly patients had significantly higher incidences of complications of AF ablation compared to the non-elderly patients (OR, 1.37; 95% CI, 1.14-1.64). However, elderly AF patients with age ≥75 years old had similar incidence of recurrent AF or ATA and complication after AF ablation compared to non-elderly patients with AF. Conclusions: The elderly patients had significantly higher incidences of recurrent AF or ATA and complications after ablation for non-paroxysmal AF compared to non-elderly patients with AF (<60 years old), except in patients ≥75 years old.

Asystole following Regadenoson administration: Review of literature, risk factors and management

Regadenoson, a selective A2A receptor agonist, is widely used for vasodilator stress myocardial perfusion imaging and has a superior adverse effect profile when compared with other agents. However, with widespread use, there have been several reported cases of Regadenoson induced bradyarrhythmias and even asystole in patients with no known conduction system disease. In this article, we report a case of asystole following Regadenoson administration, evaluate mechanisms and risk factors for Regadenoson induced bradyarrhythmias to better identify patients at risk. We also review the available treatment options and propose recommendations for limiting its risk.

Efficacy, safety, and long-term survival of concomitant valve replacement and bipolar radiofrequency ablation in patients aged 70 years and older: a comparative study with propensity score matching from a single-Centre

Background

Concomitant bipolar radiofrequency ablation and valve replacement in the elderly remains controversial. In the current study, we aimed to compare the outcomes of concomitant valve replacement and bipolar radiofrequency ablation with valve replacement alone in elderly patients with atrial fibrillation (AF).

Methods

This was a retrospective study of patients aged ≥70 years who underwent valve replacement with or without bipolar radiofrequency ablation in a single-centre between January 2006 and March 2015. The early postoperative results and long-term clinical outcomes were compared after propensity score matching.

Results

A total of 34 pairs of patients (73.94 ± 2.64 years old; 34 in the AF with ablation group and 34 in the AF without ablation group) were enrolled in the propensity score matching analysis. There were no significant differences between the two matched groups in terms of surgical mortality (5.88% vs. 2.94%, P = 0.555) and major postoperative morbidity. Kaplan–Meier analysis revealed a significantly better overall survival in the AF with ablation group compared to the AF without ablation group (P = 0.009). Cumulative incidence curves showed a lower incidence of cardiovascular death in the AF with ablation group (P = 0.025, Gray’s test). Patients in the AF with ablation group had a reduced incidence of stroke compared to patients in the AF with ablation group (P = 0.009, Gray’s test). The freedom from AF after 5 years was 58.0% in the AF with ablation group and 3.0% in the AF without ablation group.

Conclusions

The addition of bipolar radiofrequency ablation is a safe and feasible procedure, even in patients aged ≥70 years, with a better long-term survival and a reduced incidence of stroke compared to valve replacement alone. These findings suggest that bipolar radiofrequency ablation should always be considered as a concomitant procedure for elderly patients with AF who require cardiac surgery. However, a large-scale, prospective, multi-centre, randomized study should be performed in the future to fully validate our findings.

Drug interactions with antimalarial medications in older travelers: a clinical guide

Increasingly older adults are traveling to international destinations with malaria as a present risk. Surveillance systems indicate that older adults are more likely to suffer severe complications from malaria. The role of health care providers in selecting an appropriate medication for chemoprophylaxis or treatment of malaria in adults becomes more difficult as older adults undergo physiologic changes that alter the pharmacokinetic and pharmacodynamic nature of medications potentially causing increased drug interactions, adverse events and altered drug action. A comprehensive literature search from 1970 to present, with a focus on the past 10 years, was conducted on drug interactions, pharmacokinetic and pharmacodynamic effects on antimalarials in adults. It was determined that due to pharmacodynamic and pharmacokinetic changes in older adults, especially renal and cardiovascular, special attention should be given to this population of travelers in order to minimize the likelihood of adverse events or altered drug efficacy. Antimalarial drug-disease interactions in older adults can occur more often due to QT prolongation, exacerbation of hypoglycemia, decreased renal elimination and decreased hepatic metabolism. Older antimalarials have well-documented drug-drug interactions. Tafenoquine, a new antimalarial, requires glucose-6-phosphate dehydrogenase screening like primaquine and monitoring of new potential drug interaction with MATE1 and OCT2 substrates. While drug-drug interactions in older travelers may occur more often as a result of polypharmacy, data did not indicate adverse reactions or decreased drug efficacy is greater compared with younger adults. Overall, with the exception of recently approved tafenoquine, much is known about antimalarial drug and disease interactions, but new drugs are always being approved, requiring travel health providers to understand the pharmacokinetics and pharmacodynamics of antimalarial drugs to predict the impact on safety and efficacy in travelers. This guide provides travel health providers with valuable insights on potential outcomes associated with drug interactions in adults and recommended monitoring or drug regimen modification.

Pharmacokinetic profiles of boosted darunavir, dolutegravir and lamivudine in aging people living with HIV

OBJECTIVES

The pharmacokinetics of antiretroviral drugs may differ in elderly people living with HIV (PLWH) because of age-related physiological changes. We aimed to assess the pharmacokinetics of several antiretroviral drugs in aging PLWH enrolled in the Swiss HIV Cohort (SHCS).

DESIGN

Full pharmacokinetic profiling nested in a multicenter, observational, prospective cohort study. Additional collection of single point pharmacokinetic data during SHCS follow-up visits (unselected PLWH).

METHODS

PLWH were eligible for the full pharmacokinetics investigation if they were over the age of 55 years, on a stable boosted darunavir-containing or dolutegravir-containing regimen. Single point measurements were prospectively collected during SHCS follow-up visits to compare antiretroviral drug exposure in aging (≥65 years) and younger (<65 years) PLWH.

RESULTS

Nineteen PLWH with a median age of 64 years participated in the full pharmacokinetic investigations. Single point pharmacokinetic data were collected for 804 PLWH with a median age of 52 years. Boosted darunavir clearance was 40% lower in aging (≥65 years) compared with younger (<65 years) PLWH, consistent with other drugs predominantly metabolized by CYP3A. Dolutegravir exposure was similar between age groups whereas lamivudine exposure increased by 11% in aging PLWH. Median boosted darunavir, dolutegravir and lamivudine t1/2 were 148%, 45% and 32% higher in aging compared with younger PLWH.

CONCLUSION

Advanced age did not affect boosted darunavir exposure to a clinically significant extent despite the observed high variability in exposure. Age minimally affected dolutegravir and lamivudine exposure. Thus, dose adjustment based on age is a priori not warranted.

A Closer Look at the 2015 Beers Criteria

The Beers Criteria identifies potentially inappropriate medications for patients who are 65 years of age and older. Initially published in 1991, the criteria have been updated multiple times, most recently in 2015. The Beers Criteria is a tool designed to alert health-care providers to the potential harms of specific medications so they may better tailor therapeutic regimens for their elderly patients. The expert panel of the 2015 update made changes to a number of previous recommendations and provided 2 new tables on select drug interactions and select medications requiring renal dose adjustments. The purpose of this review is to provide additional details and rationale behind selected noteworthy changes within the 2015 criteria. Specific information is provided on the changes in recommendations for the use of nitrofurantoin, antiarrhythmics, nonbenzodiazepine receptor agonist hypnotics, antipsychotics, and proton pump inhibitors in the elderly. Additional comparisons are made between the 2012 recommendations and newer recommendations made in the 2015 update, along with rationale for the change. This review will allow practitioners to apply the 2015 Beers Criteria and integrate their clinical judgment when evaluating and selecting drug therapy for elderly patients.

Emergency Department Readmission in Elderly Patients After Acute Rhythm or Rate Control Treatment for Atrial Fibrillation

Atrial fibrillation (AF) is an age-related increasing disease, characterized by a high number of relapses frequently leading the patients to Emergency Department (ED). Despite AF relapses may be clinically heterogeneous, a proper management requires either a fast and effective restore of the sinus rhythm or a satisfactory control of the ventricular rate. Whether the strategy adopted in the ED could affect the course of disease is still debated. Therefore, the aim of our study was to evaluate the number of ED readmission for AF related symptoms and the event-free period in patients older than 70 years previously treated in ED for an AF recurrence, in order to assess a possible relationship with the acute strategy. An overall number of 302 recurrences of AF were drawn randomly, regarding 102 patients (mean age 78 years). We found that 206 cases (68.2%) were treated with rhythm restoration strategy (RR) whereas 96 (31.8%) with rate control strategy (RC). The median following event-free period was 118.6 +/- 15.5 and 212.9 +/- 37.1 days (p < 0.05) for RR and RC strategy, respectively. Within 6 months, 124 (60.1%) out of RR group patients and only 44 (45.8%) out of RC group patients had to be readmitted to ED for AF related symptoms (whether a recurrence or inefficient rate control symptoms) (p< 0.05). This advantage was substantially confirmed (79.1% vs 65.6% respectively, p < 0.05) after a 12 months follow-up. Our results indicate that acute treatment of AF may affect the long-term outcome of the disease and the ED readmission rate of the patient. Ventricular rate control seems to be associated with a longer event-free period if compared to the rhythm control strategy in the elderly patients. This suggests an age-based work-up of patients admitted to the ED, preferentially using ventricular rate control in elderly subjects.

Emerging concepts on the use of antiretroviral therapy in older adults living with HIV infection

PURPOSE OF REVIEW

With the overwhelming success of combination antiretroviral therapy, HIV infection is now a chronic, but manageable, medical condition. Consequently, HIV-infected cohorts are ageing leading to new challenges in the life-long management of this condition. Here, we review recent data concerning the modern treatment of older HIV-infected adults.

RECENT FINDINGS

HIV-infected cohorts are ageing with the majority of those infected predicted to be more than 50 years old within the next 2 decades. There is emerging evidence of increased antiretroviral drug exposure in older individuals, but the evidence this leads to increased toxicity is less clear-cut. In addition, the choice of antiretroviral agents is more challenging in older HIV-infected patients because of the presence of comorbidities, which occur more commonly and at a younger age than in HIV-uninfected individuals and because of a higher propensity for drug-drug interactions due to the use of concomitant medications. Specific recommendations regarding antiretroviral treatment of older HIV-infected individuals are lacking and prospective trials in older age groups are urgently needed.

SUMMARY

The use of antiretroviral therapies in older individuals is complex. Development of novel antiretrovirals and antiretroviral combinations with a low propensity for toxicity, drug-drug interactions and reliable pharmacology regardless of age is urgently needed.

Interactions of Short-Term and Chronic Treadmill Training With Aging of the Left Ventricle of the Heart

With aging, there is a decline in cardiac function accompanying increasing risk of arrhythmias. These effects are likely to be mechanistically associated with age-associated changes in calcium regulation within cardiac myocytes. Previous studies suggest that lifelong exercise can potentially reduce age-associated changes in the heart. Although exercise itself is associated with changes in cardiac function, little is known about the interactions of aging and exercise with respect to myocyte calcium regulation. To investigate this, adult (12 months) and old (24 months) C57/Bl6 mice were trained using moderate-intensity treadmill running. In response to 10 weeks’ training, comparable cardiac hypertrophic responses were observed, although aging independently associated with additional cardiac hypertrophy. Old animals also showed increased L- and T-type calcium channels, the sodium–calcium exchange, sarcoendoplasmic reticulum calcium ATPase, and collagen (by 50%, 92%, 66%, 88%, and 113% respectively). Short-term exercise training increased D-type and T-type calcium channels in old animals only, whereas an increase in sodium–calcium exchange was seen only in adult animals. Long-term (12 months) training generally opposed the effects of aging. Significant hypertrophy remained in long-term trained old animals, but levels of sarcoendoplasmic reticulum calcium ATPase, sodium–calcium exchange, and collagen were not significantly different from those found in the adult trained animals.

Medication-related fall incidents in an older, ambulant population: the B-PROOF study

BACKGROUND

Medication use is a potentially modifiable risk factor for falling; psychotropic and cardiovascular drugs have been indicated as main drug groups that increase fall risk. However, evidence is mainly based on studies that recorded falls retrospectively and/or did not determine medication use at the time of the fall. Therefore, we investigated the associations indicated in the literature between medication use and falls, using prospectively recorded falls and medication use determined at the time of the fall.

METHODS

Data from the B-PROOF (B-vitamins for the prevention of osteoporotic fractures) study were used, concerning community-dwelling elderly aged ≥65 years. We included 2,407 participants with pharmacy dispensing records. During the 2- to 3-year follow-up, participants recorded falls using a fall calendar. Cox proportional hazard models were applied, adjusting for potential confounders including age, sex, health status variables and concomitant medication use.

RESULTS

During follow-up, 1,147 participants experienced at least one fall. Users of anti-arrhythmic medication had an increased fall risk (hazard ratio [HR] 1.61; 95% confidence interval [CI] 1.12-2.32) compared with non-users. Similarly, non-selective beta-blocker use was associated with an increased fall risk (HR 1.41 [95% CI 1.12-1.78]), while statin use was associated with a lower risk (HR 0.81 [95% CI 0.71-0.94]). Benzodiazepine use (HR 1.32 [95% CI 1.02-1.71]), and antidepressant use (HR 1.40 [95% CI 1.07-1.82]) were associated with an increased fall risk. Use of other cardiovascular and psychotropic medication was not associated with fall risk.

CONCLUSION

Our results strengthen the evidence for an increased fall risk in community-dwelling elderly during the use of anti-arrhythmics, non-selective beta-blockers, benzodiazepines, and antidepressant medication. Clinicians should prescribe these drugs cautiously and if possible choose safer alternatives for older patients.

Clinical Predictors of Pacemaker Implantation in Patients with Syncope Receiving Implantable Loop Recorder with or without ECG Conduction Abnormalities

BACKGROUND

Implantable loop recorders (ILR) allow prolonged cardiac rhythm monitoring and improved diagnostic yield in syncope patients. Predictive factors for pacemaker (PM) implantation in the ILR population with unexplained syncope have not been adequately investigated. In this single center, retrospective, observational study we investigated factors that predict PM implantation in this population.

METHODS

We retrospectively analyzed our ILR database of patients aged over 18 years who underwent ILR implantation for unexplained syncope between January 2009 and June 2013. Patient case notes were examined for demographics, history, electrocardiogram (ECG) abnormalities, investigations, and events during follow-up. The primary end-point was the detection of a symptomatic or asymptomatic bradycardia requiring PM implantation.

RESULTS

During a period of 4.5 years, 200 patients were implanted with ILR for unexplained syncope, of who n = 33 (16.5%) had clinically significant bradycardia requiring PM implantation. After multivariable analysis, history of injury secondary to syncope was found to be the strongest independent predictor for PM implantation (odds ratio [OR]:9.1; P < 0.001; 95% confidence interval [CI]: (3.26-26.81). Other significant predictors included female sex, PR interval > 200msec, and age >75 years. In patients without conduction abnormalities on the ECG, history of injury secondary to syncope was found to be the strongest independent predictor for PM implantation (OR: 8.16; P = 0.00027; 95% [CI]: (2.67-26.27).

CONCLUSIONS

A history of injury secondary to syncope and female sex were independent predictive factors for bradycardia necessitating PM implantation in patients receiving an ILR for syncope with or without ECG conduction abnormalities.

Inappropriate prescribing in a large community-dwelling older population: a focus on prevalence and how it relates to patient and physician characteristics

WHAT IS KNOWN AND OBJECTIVE

The prescription of potentially inappropriate medications (PIMs) for older adults is a well-known population health concern. Updated country-specific estimates of inappropriate prescribing in older adults using germane explicit criteria are needed to facilitate physician-tailored quality improvement strategies. Therefore, we sought to determine the prevalence of PIMs for older adults in Emilia-Romagna, Italy, using the updated Maio criteria. We also evaluated patient and general practitioner (GP) characteristics related to inappropriate prescribing.

METHODS

Older adults (≥ 65) in 2012 were evaluated in a one-year retrospective study using administrative health care data. The 2011 Maio criteria includes 25 medications reimbursed by the Italian National Formulary, in the following categories in terms of severity: 16 medications that 'should always be avoided,' 3 that are 'rarely appropriate,' and 6 that have 'some indications although they are often misused.' To evaluate the extent of associations between patient and GP related characteristics, we used generalized estimating equations with an exchangeable covariance design to fit robust logistic regression models.

RESULTS AND DISCUSSION

A total of 865,354 older adults were in the cohort and 28% had at least one PIM. Of the entire cohort, 8%, 10%, and 14% of individuals were prescribed at least one medication that 'should always be avoided,' is 'rarely appropriate,' and has 'some indications but are often misused,' respectively. Older patients (≥ 75) and females were more likely to be exposed to PIMs. 2,923 GPs were identified in the region, each having prescribed at least one PIM, of which older GPs (≥ 56), male GPs, and solo practice GPs were more likely to prescribe PIMs to their older patients.

WHAT IS NEW AND CONCLUSION

The high prevalence of PIM exposure among older adults is a substantial issue in the region. Knowing how patient and GP characteristics relate to PIMs exposure may improve the design and targeting of initiatives for improving prescribing safety in this population.

Relationship between seasonal weather changes, risk of dehydration, and incidence of severe bradyarrhythmias requiring urgent temporary transvenous cardiac pacing in an elderly population

There is little information on any seasonal variations or meteorological factors associated with symptomatic bradyarrhythmias requiring cardiac pacing. The aim of this single-center study was to investigate the seasonal distribution of the incidence of severe, life-threatening bradyarrhythmias requiring urgent temporary transvenous cardiac pacing in an elderly population. Consecutive patients who underwent urgent temporary transvenous cardiac pacing between 2007 and 2012 were enrolled. The baseline characteristics of the patients and some meteorological parameters, including the calculation the daily heat index (HI), were recorded. During the study period, 79 consecutive patients (mean age 82 ± 8 years, 41% male) underwent urgent temporary transvenous cardiac pacing, mainly for third-degree atrioventricular block (79%). The incidence of bradyarrhythmias was significantly higher in summer than in the other seasons (P < 0.001). Moreover, the highest incidence was observed in months with HI > 90 °F for >3 h per day for at least 10 days (P < 0.001). A direct correlation was found between the average monthly temperature and the monthly number of patients undergoing temporary cardiac pacing (r = 0.54, P < 0.001). Compared with other patients, those observed during the hottest months were significantly older and more frequently affected by chronic disabling neurological diseases (all P < 0.05). In addition, they more frequently showed biochemical indices of dehydration, renal function impairment and hyperkalemia (all P < 0.05). This study showed an increased incidence of severe bradyarrhythmias in an elderly population during the hottest months of the year. In these months, in subjects characterized by increased susceptibility to dehydration, the risk of developing bradyarrhythmias was increased significantly.

Effects of age on antiretroviral plasma drug concentration in HIV-infected subjects undergoing routine therapeutic drug monitoring

OBJECTIVES

The pharmacokinetic and pharmacodynamic effects of antiretroviral therapy may differ in older compared with younger subjects with HIV infection. We aimed to assess factors associated with plasma antiretroviral drug exposure, including age, within a large HIV-infected cohort undergoing therapeutic drug monitoring (TDM).

METHODS

Data from the Liverpool TDM Registry were linked with the UK Collaborative HIV Cohort (CHIC) Study. All TDM of protease inhibitors (PIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs) was included and in order to account for different antiretroviral drugs the plasma concentrations were standardized by group measurements according to drug, dosing and timing of TDM. Regression modelling was used to evaluate associations of drug exposure with age and clinical parameters, including hepatic transaminase results and time to antiretroviral treatment modification.

RESULTS

Data from 3589 TDM samples were available from 2447 subjects. The greatest numbers of plasma concentrations were assessed for lopinavir (22.4%), efavirenz (18.5%), atazanavir (17.0%) and saquinavir (11.6%). As age increased, median standardized NNRTI concentrations remained constant, whereas PI concentrations increased (correlation coefficient 0.04, P = 0.033). In a regression analysis stratified by antiretroviral drug class, standardized plasma concentrations were significantly associated with age for PIs (0.05 increase in standard deviation of drug concentration with each 10 year increase in age, P = 0.044), but not for NNRTIs or other clinical parameters, including hepatic transaminase results or time to antiretroviral treatment modification.

CONCLUSIONS

With increasing age, statistically significant rises in plasma PI exposure, but not NNRTI exposure, were observed. The clinical relevance of this observation merits further investigation.