Cardiovascular drug therapy in the elderly

Prevalence and Risk Score for Hypertonic Dehydration among Community-Dwelling Older Adults: An Analysis of the Bangkok Falls Study

INTRODUCTION

Dehydration is associated with morbidity, and many factors affect dehydration in older adults including age and medication use. This study determined the prevalence of hypertonic dehydration (HD) and factors affecting HD in older adults and developed a risk score (a set of consistent weights that assign a numerical value to each risk factor) which is potentially useful in predicting HD among community-dwelling Thai older adults.

METHODS

Data were obtained from a cohort study of community-dwelling older adults aged ≥60 years in Bangkok, Thailand, between October 1, 2019, and September 30, 2021. Current HD was defined as a serum osmolality >300 mOsm/kg. Univariate and multivariate logistic regression analyses were used to identify factors associated with current and impending HD. The risk score for current HD was developed based on the final multiple logistic regression model.

RESULTS

A total of 704 participants were included in the final analysis. In this study, 59 (8.4%) participants had current HD and 152 (21.6%) had impending HD. We identified three risk factors for HD in older adults: age ≥75 years (adjusted odds ratio [aORs] 2.0, 95% confidence interval [CI]: 1.16-3.46), underlying diabetes mellitus (aORs 3.07, 95% CI: 1.77-5.31), and use of β-blocker medication (aORs 1.98, 95% CI: 1.04-3.78). The increasing risks of current HD with increasing risk scores were 7.4% for a score of 1, 13.8% for a score of 2, 19.8% for a score of 3, and 32.8% for a score of 4.

CONCLUSION

One-third of the older adults in this study had current or impending HD. We identified risk factors for HD and created a risk score for HD in one group of community-dwelling older adults. Older adults with risk scores of 1-4 were at 7.4%-32.8% risk for current HD. The clinical utility of this risk score requires further study and external validation.

Molecular Modes of Action of an Aqueous Nerium oleander Extract in Cancer Cells In Vitro and In Vivo

Cancer drug resistance remains a major obstacle in clinical oncology. As most anticancer drugs are of natural origin, we investigated the anticancer potential of a standardized cold-water leaf extract from Nerium oleander L., termed Breastin. The phytochemical characterization by nuclear magnetic resonance spectroscopy (NMR) and low- and high-resolution mass spectrometry revealed several monoglycosidic cardenolides as major constituents (adynerin, neritaloside, odoroside A, odoroside H, oleandrin, and vanderoside). Breastin inhibited the growth of 14 cell lines from hematopoietic tumors and 5 of 6 carcinomas. Remarkably, the cellular responsiveness of odoroside H and neritaloside was not correlated with all other classical drug resistance mechanisms, i.e., ATP-binding cassette transporters (ABCB1, ABCB5, ABCC1, ABCG2), oncogenes (EGFR, RAS), tumor suppressors (TP53, WT1), and others (GSTP1, HSP90, proliferation rate), in 59 tumor cell lines of the National Cancer Institute (NCI, USA), indicating that Breastin may indeed bypass drug resistance. COMPARE analyses with 153 anticancer agents in 74 tumor cell lines of the Oncotest panel revealed frequent correlations of Breastin with mitosis-inhibiting drugs. Using tubulin-GFP-transfected U2OS cells and confocal microscopy, it was found that the microtubule-disturbing effect of Breastin was comparable to that of the tubulin-depolymerizing drug paclitaxel. This result was verified by a tubulin polymerization assay in vitro and molecular docking in silico. Proteome profiling of 3171 proteins in the NCI panel revealed protein subsets whose expression significantly correlated with cellular responsiveness to odoroside H and neritaloside, indicating that protein expression profiles can be identified to predict the sensitivity or resistance of tumor cells to Breastin constituents. Breastin moderately inhibited breast cancer xenograft tumors in vivo. Remarkably, in contrast to what was observed with paclitaxel monotherapy, the combination of paclitaxel and Breastin prevented tumor relapse, indicating Breastin's potential for drug combination regimens.

Combining Antidepressants with β-Blockers: Evidence of a Clinically Significant CYP2D6 Drug Interaction

BACKGROUND

The β-blockers and antidepressants are two of the most commonly prescribed drug classes in the United States. Several antidepressants are potent inhibitors of cytochrome P450 2D6 liver enzymes (CYP2D6) and can increase the plasma concentrations of certain β-blockers when administered concomitantly, potentially leading to serious medical consequences such as hypotension, bradycardia, and falls.

OBJECTIVE

The primary objective of this investigation was to determine whether initiating an antidepressant in patients receiving β-blockers increased the risk of hemodynamic adverse events. Our primary outcome was time to hospital admissions or emergency department (ED) visits for an International Classification of Diseases-9 diagnosis suggestive of excessive β-blockade.

METHODS

We conducted a survival analysis for adults continuously enrolled in the California Medicaid system (Medi-Cal) between 2004 and 2012. Eligible patients were required to be receiving β-blocker medications that are primarily CYP2D6 substrates (e.g., metoprolol, propranolol, or carvedilol). Univariate and multivariable analyses were performed for patients who concurrently received antidepressants with β-blockers. An additional multivariable analysis analyzed the association of this combination upon hospitalizations or ED visits for all causes.

RESULTS

A total of 21,292 beneficiaries met the inclusion criteria, and 4.3% of patients required hospitalization or ED visits within 30 days of co-medication. In multivariable analysis, patients receiving antidepressants with moderate to strong CYP2D6 inhibitory potential (fluoxetine, paroxetine, duloxetine, or bupropion) had a greater risk for hospitalization or ED visits for hemodynamic events than those initiated on antidepressants with weak CYP2D6 inhibition for 30 days or less when each was compared with patients receiving no antidepressants (hazard ratio [HR] 1.53, 95% confidence interval [CI] 1.03-2.81; p=0.04 vs HR 1.24; 95% CI 0.82-1.88; p=0.30). Other demographic variables associated with increased morbidity included advanced age, male sex, higher β-blocker doses, and African American race or Hispanic ethnicity.

CONCLUSIONS

Results of this analysis suggest that initiation of certain antidepressants was associated with an increased risk for serious medical sequelae among patients concurrently receiving β-blockers. Greater risk was observed with antidepressants that potently inhibit the CYP2D6 enzyme, implying that increased morbidity may be mediated by a metabolic drug interaction.

Why deprescribing instead of not prescribing?

Prescribing medications involves complex cognitive processes, and mistakes in prescription can cause serious adverse events. Deprescribing is one of the last opportunities to prevent patient harm from the use of drugs that should be avoided, especially among older patients. This viewpoint article aims to discuss the prescription process and some essential concepts, such as polypharmacy, prescription of potentially inappropriate medications, and, particularly, the relevance of deprescribing and its relationship with the appropriate prescription of medications in older people.

Outcome Definition Influences the Relationship Between Genetic Polymorphisms of ERCC1, ERCC2, SLC22A2 and Cisplatin Nephrotoxicity in Adult Testicular Cancer Patients

Although previous research identified candidate genetic polymorphisms associated with cisplatin nephrotoxicity, varying outcome definitions potentially contributed to the variability in the effect size and direction of this relationship. We selected genetic variants that have been significantly associated with cisplatin-induced nephrotoxicity in more than one published study (SLC22A2 rs316019; ERCC1 rs11615 and rs3212986; ERCC2 rs1799793 and rs13181) and performed a replication analysis to confirm associations between these genetic polymorphisms and cisplatin nephrotoxicity using various outcome definitions. We included 282 germ cell testicular cancer patients treated with cisplatin from 2009-2014, aged >17 years recruited by the Canadian Pharmacogenomics Network for Drug Safety. Nephrotoxicity was defined using four grading tools: (1) Common Terminology Criteria for Adverse Events (CTCAE) v4.03 for acute kidney injury (AKI) or CTCAE-AKI; (2) adjusted cisplatin-induced AKI; (3) elevation of serum creatinine; and (4) reduction in the estimated glomerular filtration rate (eGFR). Significant associations were only found when using the CTCAE v4.03 definition: genotype CA of the ERCC1 rs3212986 was associated with decreased risk of cisplatin nephrotoxicity (ORadj = 0.24; 95% CI:0.08-0.70; p= 0.009) compared to genotype CC. In contrast, addition of allele A at SLC22A2 rs316019 was associated with increased risk (ORadj = 4.41; 95% CI:1.96-9.88; p < 0.001) while genotype AC was associated with a higher risk of cisplatin nephrotoxicity (ORadj = 5.06; 95% CI:1.69-15.16; p= 0.004) compared to genotype CC. Our study showed that different case definitions led to variability in the genetic risk ascertainment of cisplatin nephrotoxicity. Therefore, consensus on a set of clinically relevant outcome definitions that all such studies should follow is needed.

Association Between Chronic or Acute Use of Antihypertensive Class of Medications and Falls in Older Adults. A Systematic Review and Meta-Analysis

BACKGROUND

Evaluating effect of acute or chronic use of antihypertensives on risk of falls in older adults.

METHODS

Data sources: Systematic search of primary research articles in CINAHL, Cochrane, EBM, EMBASE, and MEDLINE databases from January 1 2007 to June 1 2017. Study selection: Research studies of cohort, case-control, case-crossover, cross-sectional, or randomized controlled trial (RCT) design examining association between antihypertensives and falls in people older than 60 years were evaluated. Data synthesis: Twenty-nine studies (N = 1,234,667 participants) were included. Study quality was assessed using the Newcastle-Ottawa Scale (NOS). PRISMA and MOOSE guidelines were used for abstracting data and random-effects inverse-variance meta-analysis was conducted on 26 articles examining chronic antihypertensive use, with odds ratios (ORs) and hazards ratios (HRs) analyzed separately. Time-risk analysis was performed on 5 articles examining acute use of antihypertensives. Outcomes: Pooled ORs and HRs were calculated to determine the association between chronic antihypertensive use and falls. For time-risk analysis, OR was plotted with respect to number of days since antihypertensive commencement, change, or dose increase.

RESULTS

There was no significant association between risk of falling and chronic antihypertensive medication use (OR = 0.97, 95% confidence interval [CI] 0.93-1.01, I2 = 64.1%, P = 0.000; and HR = 0.96, 95% CI 0.92-1.00, I2 = 0.0%, P = 0.706). The time-risk analysis demonstrated a significantly elevated risk of falling 0-24 hours after antihypertensive initiation, change, or dose increase. When diuretics were used, the risk remained significantly elevated till day 21.

CONCLUSIONS

There is no significant association between chronic use of antihypertensives and falls in older adults. Risk of falls is highest on day zero for all antihypertensive medications.

The burden and management of cytochrome P450 2D6 (CYP2D6)-mediated drug-drug interaction (DDI): co-medication of metoprolol and paroxetine or fluoxetine in the elderly

PURPOSE

Metoprolol and paroxetine/fluoxetine are inevitably co-prescribed because cardiovascular disorders and depression often coexist in the elderly. This leads to CYP2D6-mediated drug-drug interactions (DDI). Because systematic evaluations are lacking, we assessed the burden of metoprolol-paroxetine/fluoxetine interaction in the elderly and how these interactions are managed in Dutch community pharmacies.

METHOD

Dispensing data were collected from the University of Groningen pharmacy database (IADB.nl, 1999-2014) for elderly patients (≥60 years) starting beta-blockers and/or antidepressants. Based on the two main DDI alert systems (G-Standard and Pharmabase), incidences were divided between signalled (metoprolol-fluoxetine/paroxetine) and not-signalled (metoprolol-alternative antidepressants and alternative beta-blockers-paroxetine/fluoxetine) combinations. Incident users were defined as patients starting at least one signalled or a non-signalled combination. G-Standard signalled throughout the study period, whereas Pharmabase stopped after 2005.

RESULTS

A total of 1763 patients had 2039 metoprolol-paroxetine/fluoxetine co-prescriptions, despite DDI alert systems, and about 57.3% were signalled. The number of metoprolol-alternative antidepressant combinations (incidences = 3150) was higher than alternative beta-blocker-paroxetine/fluoxetine combinations (incidences = 1872). Metoprolol users are more likely to be co-medicated with an alternative antidepressant (incidences = 2320) than paroxetine/fluoxetine users (incidences = 1232) are. The number of paroxetine/fluoxetine users co-prescribed with alternative beta-blockers was comparable to those co-medicated with metoprolol (about 50%). Less than 5% of patients received a substitute therapy after using metoprolol-paroxetine/fluoxetine. Most of the metoprolol users (90%) received a low dose (mean DDD = 0.47) regardless whether they were prescribed paroxetine/fluoxetine.

CONCLUSION

Despite the signalling software, metoprolol-paroxetine/fluoxetine combinations are still observed in the elderly population. The clinical impact of these interactions needs further investigation. Copyright © 2017 John Wiley & Sons, Ltd.

Pharmacologic management of chronic stable angina

Chronic stable angina is a significant problem in older adults. The goal of therapy is to provide symptomatic relief, improve patient quality of life, and prevent subsequent angina or myocardial infarction that could lead to sudden death. The efficacy and safety of drugs such as beta-blockers and calcium channel blockers for managing chronic stable angina in older adults has not been rigorously investigated. Drug selection should be based on physiologic alterations, patient comorbidities, adverse reaction profile, and cost.

Digoxin intoxication: An old enemy in modern era

Objectives

Although development of new treatment modalities limited digoxin usage, digoxin intoxication is still an important issue which could be easily overlooked. In this report, we analyzed a case series definitively diagnosed as digoxin intoxication in the modern era.

Methods

We analyzed 71 patients hospitalized with digoxin intoxication confirmed by history, complaints, clinical and electrocardiograph (ECG) findings, and serum digoxin levels > 2.0 ng/mL, during a five year period. The demographic and clinical data, indications for digoxin use, digoxin dosage, concurrent medications, laboratory data, hospital monitoring, and ECG findings were obtained from all patients.

Results

Thirty-eight of 71 patients (53.5%) had symptoms of heart failure during admission or later. Sixty-four percent of patients were older than 75 years. The percentage of females was 67%. Atrial fibrillation, hypertension and gastrointestinal complaints were more frequent in the females (64% in females, 30% in males, P = 0.007; 81% in female, 52% in males, P = 0.01; 50% in female, 17.3% in males, P = 0.008, respectively). The mortality rate during the hospital course was 7%.

Conclusions

This report demonstrated the reduced mortality rates in patients with digoxin intoxication over the study period. Gastrointestinal complaints are the most common symptoms in this population.

Pharmacokinetics and pharmacodynamic changes associated with aging and implications for drug therapy

The population of older adults continues to increase, and polypharmacy in this population is more the rule than the exception. Physiologic changes that occur with aging result in multiple alterations to the pharmacokinetics and pharmacodynamics of drugs, which, in turn, increase the risk of adverse drug reactions. Consideration of initial dose adjustment, along with frequent medication reconciliation and analysis of the medication list, are keys to providing optimal pharmaceutical care for elderly patients.

Role of β-adrenergic receptors in regulation of hepatic fat accumulation during aging

Excessive fat accumulation in liver (hepatic steatosis) predisposes to hepatic functional and structural impairment and overall metabolic risk. Previous studies noted an association between hepatic steatosis and age in humans and rodents. However, the mechanisms leading to age-associated hepatic fat accumulation remain unknown. Earlier work from our group showed that β-adrenergic receptor (β-AR) levels and β-AR-stimulated adenylyl cyclase activity increase in rat liver during aging. Here we investigated whether age-associated increases in β-AR signaling play a role in augmenting hepatic lipid accumulation. We demonstrate an increase in hepatic lipid content during senescence and a significant correlation between hepatic fat content and stimulation of adenylyl cyclase activity by the β-AR agonist isoproterenol in rat liver. Isoproterenol administration to young and old rodents in vivo increased hepatic lipid accumulation. Furthermore, in vitro overexpression of β1- and β2-AR subtypes in hepatocytes from young rodents increased cellular lipid content, whereas inhibition of β-ARs by receptor subtype-specific inhibitors reduced lipid levels in hepatocytes from senescent animals. Isoproterenol-induced hepatic lipid accumulation in vivo was prevented by the β-AR nonselective blocker propranolol, suggesting a novel therapeutic effect of this class of drugs in hepatic steatosis. Acipimox, which inhibits adipose tissue lipolysis, did not alter isoproterenol-mediated hepatic fat accumulation; thus β-AR responsive hepatic lipid accumulation does not appear to be related primarily to altered lipolysis. These findings suggest that augmented hepatic β-AR signaling during aging may increase lipid accumulation in liver and advocate a possible role for β-adrenergic blockers in preventing or retarding the development of hepatic steatosis.

Emergency step-by-step specific immunotherapy in severe digoxin poisoning: an observational cohort study

OBJECTIVE

To evaluate the efficacy and safety of a step-by-step fixed dose of specific immunotherapy protocol in case of severe digoxin poisoning in an open uncontrolled prospective study.

METHODS

Twenty consecutive patients were admitted because of severe digoxin poisoning. The inclusion criteria were: digoxin overdose and either life-threatening arrhythmia; high-degree atrioventricular block, ventricular arrhythmia, or bradycardia less than 50 bpm and hyperkalaemia (>5.5 mmol/l). A two-step protocol of antidigoxin antibodies treatment was carried out. At admission, every patient received two vials of specific Fab-fragments. If after 1 h following infusion ECG signs regressed, no more treatment was given. If ECG signs did not regress, patients were given two more vials. At inclusion and 6 h after immunotherapy, clinical (cardiac rhythm, ECG records) and biological (serum digoxin concentration, potassium) findings were recorded.

RESULTS

Patients had a median (interquartile range) age of 83 (75-90) years. Four patients had acute poisoning and 16 chronic overdoses. Eleven patients showed ventricular arrhythmia, and five had high-degree atrioventricular block. Seventy percent of the patients needed only the first step. Significant decreases were observed in the number of cardiac dysrhythmia (16 vs. three patients), in the median (interquartile range) of serum digoxin concentration [5 microg/l (3.8-6.2) vs. 0.4 microg/l (0.3-2.2)] and in serum potassium [4.6 mmol/l (4.1-5.5) vs. 3.85 mmol/l (3.7-4.55)] before and after immunotherapy. The digoxin-related mortality was 5%.

CONCLUSION

This protocol of step-by-step digoxin-specific immunotherapy seems to be as effective as the equimolar treatment, and there was significant cost reduction in case of acute poisoning.

What limits for acute care in the elderly?

PURPOSE OF REVIEW

This review aims to address the important question of the increasing life expectancy and the aging population in the healthcare system today. We try to give some elements that will help the reflection about the ethical stakes balancing the necessity of care in the increasing number of elderly patients and the limited resources available, in the special context of acute care.

RECENT FINDINGS

There is growing evidence that the chronological age itself is not a reliable marker of bad prognosis or of mortality. The new concept of frailty may better correlate with the aging process of the elderly. The frailty index is an integrative approach considering the multiple factors impacting on the aging individual. Applied in the practical arena, it might become a useful tool for clinicians.

SUMMARY

Aging implies many biological modifications at molecular, cellular, organic levels as well as of the behavior. Some aspects of these processes and their consequences on health are described. The frailty concept is detailed, and its potential interest explained. We conclude that the measurement of aging phenomenon, including the frailty index, may help us to better assess the true health and the required therapeutics of elderly patients.