Pharmacologic Treatment of Hypertension in Older Adults

The authors conducted a review of pharmacologic therapy in older adults with hypertension. They reviewed the evidence supporting their use in older adults, understanding the physiologic changes and potential adverse drug effects associated with aging and antihypertensive medication use, exploring guideline recommendations for antihypertensive use in older adults, and evaluating the associated risks and benefits of specific classes of antihypertensive medications.

Geriatric drug delivery - barriers, current technologies and the road ahead

The geriatric population encompasses the largest part of the health care system worldwide. Chronic medical conditions are highly prevalent in the elderly, consequently, due to their complex health needs, there is a significant rate of multi-drug therapy. Despite the high numbers of medications prescribed, geriatric patients face several barriers when it comes to successful drug delivery including alterations in cognitive and physical function. The current review highlights the impact of chronic diseases on the ageing population along with how changes in drug pharmacokinetics could impact drug efficacy and safety. Also discussed are applications of administration routes in the geriatric population and complications that could arise. A focus is placed on the traditional and upcoming drug delivery advancements being employed in seniors with a focus addressing obstacles faced by this patient category. Nanomedicines, three-dimensional printing, long-acting formulations, transdermal systems, orally disintegrating tablets, and shape/taste modification technologies are discussed. Several barriers to drug delivery in the elderly have been identified in literature and directions for future studies should focus on addressing these gaps for geriatric drug formulation development including personalised medicine, insights into novel drug delivery systems like nanomedicines, methods for decreasing pill burden and shape/size modifications.ARTICLE HIGHLIGHTSTypically, senior citizens take more medications than any other patient population, yet most drug delivery technologies are not tailored to address the specific cognitive and physical barriers that these individuals encounter.The safety of drug delivery systems in the elderly patients should be prioritised with considerations on changes in pharmacokinetics with age, use of non-toxic excipients, and selecting drugs with minimal off-target side effects.Several commercialised and upcoming drug delivery technologies have begun to address the current limitations that the ageing population faces.Future research should focus on applying novel strategies like 3D printing, personalised medicine, and long-acting formulations to improve drug delivery to elderly patients.

Pharmacokinetics, safety, and efficacy of daridorexant in Japanese subjects: Results from phase 1 and 2 studies

Daridorexant is a dual orexin receptor antagonist for the treatment of insomnia. We report results from the first two randomised, double-blind clinical studies of daridorexant in Japanese subjects. In the Phase 1 study, daridorexant (10, 25, 50 mg) or placebo were administered in the morning for 4 days in 24 young (mean age 26.9 years) and 24 older (mean age 69.7 years) healthy Japanese adults. Daridorexant reached a peak plasma concentration within 1.0 h across every dose and age group. For all doses, the mean plasma concentration of daridorexant showed a similar change between the age groups. Exposure parameters increased dose-dependently with minimal/no accumulation upon repeated dosing. The terminal half-life was ~8 h. In the Phase 2, four-period, four-way crossover study, 47 Japanese subjects (mean age 50.4 years) with insomnia disorder were randomised to receive four treatments (daridorexant 10, 25, 50 mg, placebo) during four treatment periods, each consisting of two treatment nights (5-12 day washout between treatment periods). Subjects continued their fourth treatment for 12 further days. A statistically significant dose-response relationship (multiple-comparison procedure-modelling, p < 0.0001) was found in the reduction of polysomnography-measured wake after sleep onset (WASO; primary endpoint) and latency to persistent sleep (secondary endpoint) from baseline to days 1/2. Statistically significant dose-response relationships were also observed for secondary subjective endpoints from baseline to days 1/2 (sWASO, latency to sleep onset). All daridorexant doses were well tolerated, with no treatment discontinuations and no next-morning residual effects. These results supported further investigation of daridorexant in Japanese patients with insomnia disorder.

Ageing-related considerations for medication used in supportive care in cancer

Both randomized controlled trials (RCTs) and retrospective studies have shown that a comprehensive geriatric assessment (CGA) prior to a patient commencing systemic anti-cancer therapy (SACT) results in improved quality of life outcomes and is associated with a decreased risk of grade 3-5 toxicity; however, data are lacking in relation to adverse drug events (ADE) associated with supportive care medications. Supportive care medications are prescribed as prophylactic agents in a SACT regimen, for management of treatment related toxicity and for symptoms caused by the disease itself. While necessary, the commencement of SACT and supportive medications may cause, or exacerbate, a significant drug burden in older patients, some of whom may have existing comorbidities. For many medications, older adults are underrepresented in pharmacokinetic and pharmacodynamic modelling studies. In this article we will review ageing-related changes in pharmacokinetics and pharmacodynamics, as well as how these changes may impact supportive care medications. Additional considerations for prescribing these medications in older adults with cancer, such as polypharmacy, potentially inappropriate medications, drug-drug interactions, and anticholinergic burden, as well as ageing-related considerations and recommendations for supportive care medications commonly used in older adults with cancer are also reviewed.

Drug-Induced Liver Injury in the Elderly: Consensus Statements and Recommendations from the IQ-DILI Initiative

The elderly demographic is the fastest-growing segment of the world's population and is projected to exceed 1.5 billion people by 2050. With multimorbidity, polypharmacy, susceptibility to drug-drug interactions, and frailty as distinct risk factors, elderly patients are especially vulnerable to developing potentially life-threatening safety events such as serious forms of drug-induced liver injury (DILI). It has been a longstanding shortcoming that elderly individuals are often a vulnerable population underrepresented in clinical trials. As such, an improved understanding of DILI in the elderly is a high-priority, unmet need. This challenge is underscored by recent documents put forward by the U.S. Food and Drug Administration (FDA) and European Medicines Agency (EMA) that encourage data collection in the elderly and recommend improved practices that will facilitate a more inclusive approach. To establish what is already known about DILI in the elderly and pinpoint key gaps of knowledge in this arena, a working definition of "elderly" is required that accounts for both chronologic and biologic ages and varying states of frailty. In addition, it is critical to characterize the biological role of aging on liver function, as well as the different epidemiological factors such as polypharmacy and inappropriate prescribing that are common practices. While data may not show that elderly people are more susceptible to DILI, DILI due to specific drugs might be more common in this population. Improved characterization of DILI in the elderly may enhance diagnostic and prognostic capabilities and improve the way in which liver safety is monitored during clinical trials. This summary of the published literature provides a framework to understand and evaluate the risk of DILI in the elderly. Consensus statements and recommendations can help to optimize medical care and catalyze collaborations between academic clinicians, drug manufacturers, and regulatory scientists to enable the generation of high-quality research data relevant to the elderly population.

Population Pharmacokinetics of Digoxin in Nonagenarian Patients: Optimization of the Dosing Regimen

OBJECTIVE

The aim of this study was to develop a population pharmacokinetic model of digoxin in patients over 90 years old and to propose an equation for adjusting digoxin dose in this population.

METHODS

We included 326 nonagenarian patients admitted to Severo Ochoa University Hospital (Spain) who received digoxin and were under therapeutic drug monitoring. All data were retrospectively collected, and population modeling was performed with non-linear mixed-effect modeling software (NONMEM®). One- and two-compartment models were tested to calculate digoxin clearance (Cl), volume of distribution (Vd), absorption rate constant (Ka), and bioavailability (bioavailable fraction, F). The covariates were evaluated by stepwise covariate model building, and the final model was internally validated by bootstrap analysis with 1000 resamples. External validation was performed with another population of 95 patients with the same characteristics as the modeling group.

RESULTS

The population was 26% males, with a mean age of 93.2 years (90-103 years), mean creatinine 1.11 mg/dL (0.42-3.81 mg/dL), and mean total body weight 61.2 kg (40-100 kg). The pharmacokinetics of digoxin were best described by a one-compartment model (ADVAN2 TRANS2), with first-order conditional estimation with interaction. The covariates with influence on our model were creatinine clearance based on the Cockcroft-Gault equation (CG), serum potassium (K), co-administration of loop diuretics, and sex: Cl/F = 4.55 · (CG/36.4)0.468 · 0.83LD · 1.21SEX; Vd/F = 355 · (K/4.3)-0.849; Ka = 1.22 h-1 [where LD indicates loop diuretics (1 for administered, 0 for otherwise) and SEX indicates patient sex (1 for male, 0 for female)]. Based on our results, we proposed an equation to adjust the digoxin dosing regimen in nonagenarian patients: dose (mg) = 0.144 · (CG/36.4)0.468 · 0.83LD · 1.21SEX.

CONCLUSIONS

The greatest influence on digoxin clearance came from renal function calculated by the Cockcroft-Gault equation. Vd was decreased by K. The model developed showed a precise predictive performance to be applied for therapeutic drug monitoring.

Safety and Tolerability of Antimicrobial Agents in the Older Patient

Older patients are at high risk of infections, which often present atypically and are associated with high morbidity and mortality. Antimicrobial treatment in older individuals with infectious diseases represents a clinical challenge, causing an increasing burden on worldwide healthcare systems; immunosenescence and the coexistence of multiple comorbidities determine complex polypharmacy regimens with an increase in drug-drug interactions and spread of multidrug-resistance infections. Aging-induced pharmacokinetic and pharmacodynamic changes can additionally increase the risk of inappropriate drug dosing, with underexposure that is associated with antimicrobial resistance and overexposure that may lead to adverse effects and poor adherence because of low tolerability. These issues need to be considered when starting antimicrobial prescriptions. National and international efforts have been made towards the implementation of antimicrobial stewardship (AMS) interventions to help clinicians improve the appropriateness and safety of antimicrobial prescriptions in both acute and long-term care settings. AMS programs were shown to decrease consumption of antimicrobials and to improve safety in hospitalized patients and older nursing home residents. With the abundance of antimicrobial prescriptions and the recent emergence of multidrug resistant pathogens, an in-depth review of antimicrobial prescriptions in geriatric clinical practice is needed. This review will discuss the special considerations for older individuals needing antimicrobials, including risk factors that shape risk profiles in geriatric populations as well as an evidence-based description of antimicrobial-induced adverse events in this patient population. It will highlight agents of concern for this age group and discuss interventions to mitigate the effects of inappropriate antimicrobial prescribing.

Assessment of alteration in antiviral plasma concentration across dialysis days: computational and analytical study

Aim: Protein-bound uremic toxins (PBUTs) may displace drugs from the plasma proteins and render them more liable to clearance. This study aims to investigate the possible interplay between PBUTs and directly acting antivirals (DAAs). Methods: PBUT plasma protein binding was compared to those of paritaprevir (PRT), ombitasivir (OMB) and ritonavir (RTV) in silico to assess the possible competitive displacement. The three drugs were LC-MS/MS determined in seven patients across dialysis and non-dialysis days and results were compared. Results & conclusion: Results showed that the PBUT exhibited a lower binding than DAA reducing the liability of their competitive displacement. This was echoed by an unaltered plasma concentration across dialysis days. Results may indicate that PBUT accumulation may have limited effect on disposition of DAA.

A North-West London Experience of the Impact of Treatment Related Toxicity on Clinical Outcomes of Elderly Patients with Germ Cell Tumors

Background/Aim: The occurrence of germ cell tumour (GCT) in the elderly is rare, with scarce data available. The aim of this study was to understand the clinical outcomes of patients with GCT in patients aged > 45 years. Materials and Methods: A retrospective study was conducted in a large tertiary cancer centre in north-west London. Between 1 January 2003 and 31 March 2022, 108 cases of GCT in men aged > 45 years were identified and treated at the Mount Vernon Cancer Centre. The median age at diagnosis was 54 years (range = 45−70 years). Results: The 5-year survival rate of all patients was 96%, and the toxicity profile was similar to the younger age group. Conclusion: Older patients with GCT are able to tolerate chemotherapy; however, care must be taken to prevent life-threatening complications using appropriate dose modification.

Efficacy and Safety of Daridorexant in Older and Younger Adults with Insomnia Disorder: A Secondary Analysis of a Randomised Placebo-Controlled Trial

Background and Objective

The dual orexin receptor antagonist daridorexant, studied in two phase III trials, dose-dependently improved objective and subjective sleep variables and daytime functioning in adults with insomnia. Because treatment of insomnia in older adults is challenging and has limited options, the purpose of the current analysis was to further analyse the phase III trial studying the higher doses of daridorexant, those that showed efficacy (daridorexant 50 mg, daridorexant 25 mg and placebo, nightly for 3 months), and compare the safety and efficacy of daridorexant in patients aged ≥ 65 (‘older adults’) to those aged < 65 years (‘younger adults’).

Methods

Analyses by age (≥ 65 years, n = 364; < 65 years, n = 566) were performed on data from the randomised, double-blind, placebo-controlled Trial 1 in adult patients with insomnia (NCT03545191). Efficacy endpoints included a change from baseline at month 1 and month 3 in polysomnography-measured wake after sleep onset (WASO) and latency to persistent sleep (LPS), self-reported total sleep time (sTST) and daytime functioning assessed using the validated Insomnia Daytime Symptoms and Impacts Questionnaire (IDSIQ). Safety endpoints included adverse events and the Visual Analog Scale for morning sleepiness.

Results

At baseline, mean [standard deviation] WASO was numerically greater (110 [39] vs 92 [38] min) in older than younger adults, while LPS was comparable (~ 65 min). Mean baseline IDSIQ total and all domain scores were numerically lower (i.e. better) in older adults. Daridorexant caused similar reductions in WASO and LPS, and similar increases in sTST, from baseline, in both age groups; improvements were numerically greater with daridorexant 50 mg than 25 mg. At month 3, daridorexant 50 mg, compared with placebo, decreased WASO by a least-squares mean of 19.6 (95% confidence interval 9.7, 29.5) in older patients versus 17.4 min (10.7, 24.0) in younger patients and decreased LPS by a least-squares mean of 14.9 (7.5, 22.3) in older patients versus 9.7 min (3.7, 15.7) in younger patients. Daridorexant 50 mg increased sTST from baseline to month 3 by a least-squares mean of 59.9 (49.6, 70.3) in older patients versus 57.1 min (48.9, 65.3) in younger patients. Daridorexant 50 mg progressively improved IDSIQ total and domain scores from week 1 onwards similarly in both groups; daridorexant 25 mg improved IDSIQ scores, but only in younger adults. In both age groups, in comparison with placebo, the overall incidence of adverse events was comparable, and there were fewer falls on daridorexant. Daridorexant improved Visual Analog Scale morning sleepiness in both groups; daridorexant 50 mg increased the mean (standard deviation) Visual Analog Scale morning sleepiness score by 15.9 (20.7) in older adults and by 14.9 (18.7) in younger adults from baseline to month 3. In older adults, there was one case of sleep paralysis, and no cases of narcolepsy, cataplexy, or complex sleep behaviour.

Conclusions

In older patients with insomnia, as in younger patients, the efficacy of daridorexant is maximal on night-time and daytime variables at the higher dose of 50 mg. Older patients particularly require this dose to improve daytime functioning. Older patients are not at an increased risk of adverse events or residual effects the next morning after night-time administration of daridorexant, even at 50 mg. The dose of daridorexant does not need to be decreased for older patients.

Clinical Trial Registration

ClinicalTrials.gov (NCT03545191) [first posted: 4 June, 4 2018], https://clinicaltrials.gov/ct2/show/NCT03545191.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40266-022-00977-4.

The burden of chronic insomnia (difficulty in falling/staying asleep or not getting enough sleep) increases with age yet treatment options in older patients are limited. In older patients, because of a risk of side effects, guidelines suggest caution when prescribing sleep medications and, for some drugs, recommend starting at a lower dose. Daridorexant was approved in 2022 for the treatment of insomnia in adults following positive results in two trials that showed daridorexant significantly improved night-time sleep and daytime functioning over 3 months of treatment in adults with insomnia. Approximately 40% of patients taking part in these trials were aged 65 years or older. This current analysis compared the safety and benefits of daridorexant in older adults (aged at least 65 years) and younger adults (aged less than 65 years) in the trial that administered the highest two doses of daridorexant, 25 and 50 mg. The results showed that the benefits of daridorexant were comparable in both age groups over 3 months; compared with placebo, daridorexant improved night-time sleep (reduced time awake during the night, reduced time to fall asleep and increased total sleep time) and daytime functioning—patients had less daytime sleepiness and a better mood and feeling of alertness. In older patients, the benefits, particularly for daytime functioning, were greatest at the higher 50-mg dose, without any increase in side effects. Both doses of daridorexant were equally well tolerated in the two age groups, indicating that treatment with daridorexant at 50 mg can be safely started in older patients.

Age-Related Change in Hepatic Clearance Inferred from Multiple Population Pharmacokinetic Studies: Comparison with Renal Clearance and Their Associations with Organ Weight and Blood Flow

OBJECTIVE

This study aimed to examine the magnitude of age-related change in hepatic clearance by integrating the data of multiple drugs and to compare this with renal clearance, considering associations with age-related changes in organ weight and blood flow.

METHODS

The results of multiple population pharmacokinetic analyses that detected age-related clearance changes in hepatically eliminated drugs were collected. The relationship between hepatic clearance of the unbound drug and age was then analyzed using the nonlinear least-squares method, adjusting for interdrug differences. The obtained change in hepatic clearance was compared with age-related changes in liver weight and hepatic blood flow in Japanese and Westerners. For comparison, the changes in renal clearance were analyzed similarly.

RESULTS

In total, 18 drugs were analyzed. The hepatic unbound clearance decreased by 32% at age 80 years and by 40% at age 90 years, compared with age 40 years, suggesting that it decreased by 0.80% per year with aging. The rate of the decrease was consistent with decreases in hepatic weight per person or blood flow per person, regardless of ethnicity and sex. Since age-related change in body weight varied somewhat by sex or ethnicity, hepatic weight per body weight was less consistent to account for age-related change in hepatic clearance. As for an index of renal clearance, the changes in inulin clearance with age were similar to those in renal blood flow, with a decrease of 0.97% per year from the age of 40 years.

CONCLUSIONS

Hepatic clearance consistently decreased by 0.80% per year from the age of 40 years, with aging for multiple drugs analyzed in this study. Changes in organ weight and blood flow are considered to be primarily responsible for the age-related changes in hepatic and renal clearance.

Adverse Drug Reactions of Acetylcholinesterase Inhibitors in Older People Living with Dementia: A Comprehensive Literature Review

The rising of global geriatric population has contributed to increased prevalence of dementia. Dementia is a neurodegenerative disease, which is characterized by progressive deterioration of cognitive functions, such as judgment, language, memory, attention and visuospatial ability. Dementia not only has profoundly devastating physical and psychological health outcomes, but it also poses a considerable healthcare expenditure and burdens. Acetylcholinesterase inhibitors (AChEIs), or so-called anti-dementia medications, have been developed to delay the progression of neurocognitive disorders and to decrease healthcare needs. AChEIs have been widely prescribed in clinical practice for the treatment of Alzheimer's disease, which account for 70% of dementia. The rising use of AChEIs results in increased adverse drug reactions (ADRs) such as cardiovascular and gastrointestinal adverse effects, resulting from overstimulation of peripheral cholinergic activity and muscarinic receptor activation. Changes in pharmacokinetics (PK), pharmacodynamics (PD) and pharmacogenetics (PGx), and occurrence of drug interactions are said to be major risk factors of ADRs of AChEIs in this population. To date, comprehensive reviews in ADRs of AChEIs have so far been scarcely studied. Therefore, we aimed to recapitulate and update the diverse aspects of AChEIs, including the mechanisms of action, characteristics and risk factors of ADRs, and preventive strategies of their ADRs. The collation of this knowledge is essential to facilitate efforts to reduce ADRs of AChEIs.

Drug metabolism in severe chronic obstructive pulmonary disease: A phenotyping cocktail study

AIMS

To evaluate the effect of severe chronic obstructive pulmonary disease (COPD) on drug metabolism by comparing the pharmacokinetics of patients with severe COPD with healthy volunteers and using the modified Inje drug cocktail.

METHODS

This was a single-centre pharmacokinetic study with 12 healthy participants and 7 participants with GOLD D COPD. Midazolam 1 mg, dextromethorphan 30 mg, losartan 25 mg, omeprazole 20 mg, caffeine 130 mg and paracetamol 1000 mg were simultaneously administered and intensive pharmacokinetic sampling was conducted over 8 hours. Drug metabolism by CYP3A4, CYP2D6, CYP2C9, CYP2C19, CYP1A2, UGT1A6 and UGT1A9 in participants with COPD were compared with phenotypes in healthy controls.

RESULTS

The oral clearance (95% confidence interval) in participants with COPD relative to controls was: midazolam 63% (60-67%); dextromethorphan 72% (40-103%); losartan 53% (52-55%); omeprazole 35% (31-39%); caffeine 52% (50-53%); and paracetamol 73% (72-74%). There was a 5-fold increase in AUC for omeprazole and approximately 2-fold increases for caffeine, losartan, dextromethorphan, and midazolam. The AUC of paracetamol, which is mostly glucuronidated, was increased by about 60%.

CONCLUSION

Severe COPD is associated with a clinically significant reduction in oral drug clearance. This may be greater for cytochrome P450 substrates than for glucuronidated drugs. This supports reduced starting doses when prescribing for patients with severe COPD.

Guidance for appropriate use of psychotropic drugs in older people

Psychotropic drugs are widely prescribed in older people although their use is associated with important risks. In this position paper, we discuss the appropriateness of using these medications in older people in terms of different aspects such as indications, contraindications, dosing, adverse drug reactions, interactions and duration of therapy. Consequently, we discuss different strategies to increase the appropriateness of therapy while formulating some practical recommendations to keep in mind when (de)prescribing psychotropic drugs in older people.

Incorporating pharmacokinetic data into personalised prescribing for older people: challenges and opportunities

PURPOSE

We discuss the known age-associated changes in drug metabolism and elimination, the potential use of this information when selecting specific therapeutic strategies in older patients, and the steps required to fill the knowledge gap in this field.

METHODS

We conducted a narrative review that encapsulates the current knowledge regarding the main age-associated changes in drug metabolism and elimination and discusses their possible inclusion in current and future personalised prescribing tools for the older patient population.

RESULTS

Despite some progress in this field, the lack of specific information regarding the impact of frailty, pharmacogenomics, and drug-drug, drug-disease, and organ-organ interactions, particularly in subjects > 80 years, currently prevents the routine incorporation of pharmacokinetic data, barring measures of renal function, into personalised prescribing tools.

CONCLUSIONS

The incorporation of pharmacokinetic data into personalised prescribing, an approach based on the consideration of a number of patient's characteristics when selecting the right drug(s) and dose regimen(s) to maximize effectiveness and limit toxicity, remains a hypothetical construct in geriatric care. Pending the inclusion of frail and complex older patients in pre- and post-marketing studies, a better understanding of the key pharmacokinetic alterations of common medications in "real-life" patients, together with the implementation of effective strategies tackling inappropriate prescribing, is likely to improve clinical outcomes and reduce healthcare utilization in the older population.

Alterations in drug disposition in older adults: a focus on geriatric syndromes

INTRODUCTION

Age-associated physiological changes can alter the disposition of drugs, however, pathophysiological changes associated with geriatric syndromes in older adults may lead to even greater heterogeneity in pharmacokinetics. Geriatric syndromes are common health problems in older adults which have multifactorial causes and do not fit into distinct organ-based disease categories. With older adults being the greatest users of medications, understanding both age- and geriatric syndrome-related changes is important clinically to ensure safe and effective medication use.

AREAS COVERED

This review provides an overview of current evidence regarding pharmacokinetic alterations that occur with aging and in common geriatric syndromes, including frailty, sarcopenia, dementia, polypharmacy and enteral feeding. The evidence is presented according to the four primary pharmacokinetic processes (Absorption, Distribution, Metabolism and Excretion).

EXPERT OPINION

There is some evidence to inform our understanding of the impact of chronological aging and various geriatric syndromes on drug disposition. However, many areas require more research, including drug induced inhibition and induction of cytochrome P450 enzymes and the clinical utility of emerging methods for estimating renal function. There is a need to develop tools to predict alterations in drug disposition in subgroups of older adults, particularly where the currently available clinical information is sparse.

Prescribing medicines to older people-How to consider the impact of ageing on human organ and body functions

Ageing is associated with several changes in human organs, which result in altered medication pharmacokinetics and pharmacodynamics. Ageing is also associated with changes in human body functions, such as impaired vision, hearing, swallowing, motor and cognitive functions, which can affect the adequate intake and administration of drugs. As a consequence, older people, and especially patients older than 75 years, are the main users of many drugs and they frequently use 5 drugs or more long-term (i.e. polypharmacy). All this increases the complexity of adequate drug intake, administration and adherence. However, there is a lack of evidence on the considerations that should be taken into account to ensure appropriate drug prescribing to older people. This review article summarizes the most clinically relevant changes in human organ and body functions and the consequential changes in pharmacokinetics and pharmacodynamics in older people, along with possible dosing consequences or alternatives for drugs frequently prescribed to this patient population. Recommendations are given on how ageing could be considered in clinical drug development, drug authorization and appropriate prescribing.

Intracellular Tenofovir and Emtricitabine Concentrations in Younger and Older Women with HIV Receiving Tenofovir Disoproxil Fumarate/Emtricitabine

The altered immune states of aging and HIV infection may affect intracellular metabolism of tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC); increased cellular senescence decreases FTC-triphosphate (FTCtp) concentrations. The effects of age and inflammation on the ratio of intracellular metabolites (IMs; tenofovir diphosphate [TFVdp] and FTCtp) to their endogenous nucleotides (ENs; dATP and dCTP), a potential treatment efficacy marker, were assessed among participants of the Women's Interagency HIV Study (WIHS), who ranged from 25 to 75 years. Samples from women receiving TDF-FTC with viral loads of <200 copies/ml were dichotomized by age at collection into two groups (≤45 years and ≥60 years). IM/EN concentrations were measured in peripheral blood mononuclear cell (PBMC) pellets; interleukin-6 (IL-6) and sCD163 were measured in plasma; senescent CD8⁺ T cells were measured in viable PBMCs. The TFVdp:dATP and FTCtp:dCTP ratios had statistically significantly different distributions in older and younger women (log-rank test, P = 0.0023 and P = 0.032, respectively); in general, IM and EN concentrations were higher in the older women. After adjusting for potential confounders, these findings were not significant. In women aged ≤45 years, TFVdp was negatively associated with IL-6 and sCD163, while FTCtp was positively associated with sCD163 and IL-6 in women aged ≥60 years. Body mass index (BMI) was positively associated with IL-6 in both age groups and negatively associated with TFVdp in women aged ≤45 years. After adjustment, age remained significant for sCD163, while black race, BMI, and renal function remained significant for several IMs and ENs, suggesting that factors associated with aging, but not age itself, govern intracellular TDF-FTC pharmacology.

Rethinking toxicity testing: Influence of aging on the outcome of long-term toxicity testing and possible remediation

Traditionally, toxicity testing is conducted at fixed dose rates (i.e., mg/kg/day) without considering life-changing events, e.g., stress, sickness, aging- and/or pregnancy-related changes in physical, physiological and biochemical parameters. In humans, life-changing events may cause systemic dose non-proportionality requiring modulation of drug dosage; similar changes occur in animals altering systemic dose during chronic/carcinogenic testing leading to "late-occurring" effects in some studies. For example, propylene monomethyl ether, an industrial chemical, initially induced sedation in rats and mice with recovery upon induction of hepatic CYPs after ~1 week. Sedation reappeared in rats but not in mice after ~12 months of exposure due to decreased CYP activity in rats, elderly mice were able to maintain slightly higher CYP activity avoiding recurrence of sedation. The systemic dose of two pharmaceuticals (doxazosin and brimonidine tartrate) increased up to 6-fold in ≥12-month old rats with no toxicity. In a rat reproductive toxicity study, systemic dose of 2,4-D, an herbicide, rapidly increased due to increased consumption of 2,4-D-fortified diet during pregnancy, lactation and neonatal growth, requiring adjustment to maintain the targeted systemic dose. Ideally, toxicological studies should be based on systemic dose with the option of modulating external dose rates to maintain the targeted systemic dose. Systemic dose can easily be monitored in selected core study animals at desired intervals considering recent developments in sampling and analysis at a fraction of the overall cost of a study.

Clinical pharmacology of the dual orexin receptor antagonist ACT-541468 in elderly subjects: Exploration of pharmacokinetics, pharmacodynamics and tolerability following single-dose morning and repeated-dose evening administration

BACKGROUND

The dual orexin receptor antagonist ACT-541468 showed sedative pharmacodynamic effects during initial clinical testing in adult subjects. The present study explored pharmacokinetics, pharmacodynamics and tolerability in healthy elderly subjects.

METHODS

Double-blind, placebo-controlled, randomised, single-ascending dose study in 24 male/female elderly (65-80 years, 5, 15 and 25 mg in the morning, 6/2 active/placebo per group). Additionally, 10 subjects (8/2 active/placebo) received 25 mg for 7 days in the evening. Pharmacokinetics, pharmacodynamics (saccadic peak velocity, adaptive tracking, body sway, visual analogue scales according to Bowdle and Bond and Lader, Karolinska Sleepiness Scale) and tolerability were assessed. In particular, pharmacodynamics results are to be interpreted exploratorily.

RESULTS

Absorption was quick with a median time to maximum concentration of ∼ 1.0 h. The mean elimination half-life was 8.5-9.8 h, the area under the curve and the maximum plasma concentration increased proportionally with dose. Following repeated evening administration of 25 mg, minimal accumulation was observed. There were no pharmacodynamic effects at 5 mg. At 15 mg, saccadic peak velocity (degree/s; SD) was reduced (69; 38), while other variables showed no effects. At 25 mg, effects on all objective pharmacodynamic parameters were observed. At 8-12 h post-dose, there were no differences to placebo and no next-day effects on pharmacodynamic variables after evening administration. Elderly subjects reported fewer adverse events compared to adults in previous studies.

CONCLUSION

ACT-541468 in elderly subjects was well tolerated and pharmacokinetics and pharmacodynamics are compatible with a drug for the treatment of insomnia. Clinicaltrials.gov: NCT02571855.

Prospective evaluation of health-related quality of life in geriatric trauma patients

BACKGROUND

Frailty is an established predictor of adverse outcomes in geriatric patients. Health-related quality of life (HRQoL) is an important outcome measure among trauma patients. This prospective observational study examined the impact of frailty on health-related quality of life in geriatric trauma patients.

METHODS

We prospectively enrolled geriatric (age ≥65 years) trauma patients. We calculated the frailty index (FI) within 24 hours of admission using the trauma-specific frailty index. Patients were stratified into frail (frailty index ≥0.27) and nonfrail (frailty index <0.27). Health-related quality of life was calculated at discharge and at 30 days (day) after discharge using the RAND Short Form-36 (SF-36). Outcome measures were health-related quality of life at discharge, 30-days postdischarge, and delta health-related quality of life. Regression analysis was performed to control for demographic, vital signs, and injury parameters.

RESULTS

We enrolled 296 patients. The mean age was 75.1 ± 9.8 years, 59% were male, and 81% were white. Frail patients accounted for 34%, and they had a lower health-related quality of life at discharge (366 vs 548, P < .01) and at 30-day postdischarge (393 vs 744, P < .01). Nonfrail patients scored higher in 6 out of 8 domains of health-related quality of life. Nonfrail patients had improved delta health-related quality of life (P < .01), unlike frail patients (P = .11). A linear regression model revealed an inverse relationship between frailty and improvement in health-related quality of life over 30-day postdischarge (β = -0.689, [confidence interval, -0.963 to -0.329] P = .01). This association remained statistically significant after controlling for potential confounding covariates, such as age, sex, race, and injury severity.

CONCLUSION

Compared with nonfrail geriatric trauma patients, those who were frail had poor health-related quality of life at discharge and at 30-day postdischarge. Frailty negatively affects the recovery of health-related quality of life after trauma. The use of frailty indices may help identify and develop targeted interventions to improve health-related quality of life among geriatric trauma patients.

Dosage considerations in the combined use of ocular-specific vitamins and nutrients and multivitamin products: A systemic review and analysis

OBJECTIVES

To provide guidance for safe and appropriate vitamin and mineral supplementation regimens for patients who use vitamins marketed for ocular use concurrently with general-purpose multivitamin (MVI) supplementation.

DATA SOURCES

Primary and tertiary evidence was compiled from secondary literature reference databases.

STUDY SELECTION

Dosage exposure with the use of supplements marketed for the prevention of ocular disease, including those recommended by the Age-Related Eye Disease Studies (AREDS), when used in combination with conventional MVI/nutrient products was determined. An analysis of the data was performed to suggest appropriate supplement recommendations.

DATA EXTRACTION

Combined dosages for single and duplicate ingredients found in ocular supplements and select MVI/nutrient supplements were compared with U.S. Food and Drug Administration--recommended daily value intake levels and the National Academy of Medicine recommendations on vitamin and nutrient tolerable upper intake levels (TUILs).

RESULTS

With the exception of copper, all studied product components that conformed to AREDS guidelines for vitamin and nutrient levels far exceeded U.S. Food and Drug Administration--recommended daily value intake level limits. Furthermore, vitamin A and zinc exceeded the National Academies of Medicine TUIL when a multivitamin product was combined with an ocular-specific vitamin or nutrient that conformed with AREDS-recommended dosage levels. Several products marketed specifically for ocular use failed to provide AREDS-recommended vitamin or nutrient levels even when combined with MVI products.

CONCLUSION

With the exception of vitamin A and zinc, the addition of typical multivitamin preparations to AREDS-recommended vitamin and nutrient regimens do not result in vitamin and mineral dosages that exceed TUIL as outlined by the National Academy of Medicine. However, combined AREDS and MVI regimens can create a substantial vitamin or mineral burden that is not appropriate for all older adult populations, particularly those with comorbidities, contributing to susceptibility of component toxicity.

Population pharmacokinetic modelling of intravenous paracetamol in fit older people displays extensive unexplained variability

AIMS

Paracetamol is the analgesic most used by older people. The physiological changes occurring with ageing influence the pharmacokinetics (PK) of paracetamol and its variability. We performed a population PK-analysis to describe the PK of intravenous (IV) paracetamol in fit older people. Simulations were performed to illustrate target attainment and variability of paracetamol exposure following current dosing regimens (1000 mg every 6 h, every 8 h) using steady-state concentration (Css-mean ) of 10 mg l-1 as target for effective analgesia.

METHODS

A population PK-analysis, using NONMEM 7.2, was performed based on 601 concentrations of paracetamol from 30 fit older people (median age 77.3 years, range [61.8-88.5], body weight 79 kg [60-107]). All had received an IV paracetamol dose of 1000 mg (over 15 min) after elective knee surgery.

RESULTS

A two-compartment PK-model best described the data. Volume of distribution of paracetamol increased exponentially with body weight. Clearance was not influenced by any covariate. Simulations of the standardized dosing regimens resulted in a Css of 9.2 mg l-1 and 7.2 mg l-1 , for every 6 h and every 8 h respectively. Variability in paracetamol PK resulted in Css above 5.4 and 4.1 mg l-1 , respectively, in 90% of the population and above 15.5 and 11.7, respectively, in 10% at these dosing regimens.

CONCLUSIONS

The target concentration was achieved in the average patient with 1000 mg every 6 h, while every 8 h resulted in underdosing for the majority of the population. Furthermore, due to a large (unexplained) interindividual variability in paracetamol PK a relevant proportion of the fit older people remained either under- or over exposed.

Invasive Candidiasis in the Elderly: Considerations for Drug Therapy

Candida infections in the elderly are an important and expanding clinical problem, with significantly higher mortality in this group than in younger patients. The increasing problem of invasive Candida infections may be related to higher prevalence of immunocompromised older people and the emergence of treatment resistance. Older people, especially the frail and critically ill, are at higher risk of medication-related harmful effects due to changes in pharmacokinetics and pharmacodynamics, which may be further complicated by organ dysfunction, diminished homeostatic control, co-morbidities and polypharmacy. Here, we review the available options for the treatment of Candida infections and provide insights into the challenges surrounding the optimal use of antifungal drugs in the elderly.

Challenges and innovations of drug delivery in older age

Both drug delivery performance and various age-related physical, mental and physiological changes can affect drug effectiveness and safety in elderly patients. The many drug delivery systems developed over the years include recent novel transdermal, nasal, pulmonary and orally disintegrating tablets that provide consistent, precise, timely and more targeted drug delivery. Certain drug delivery systems may be associated with suboptimal outcomes in the elderly because of the nature of drug present, a lack of appreciation of the impact of age-related changes in drug absorption, distribution and clearance, the limited availability of pharmacokinetic, safety and clinical data. Polypharmacy, patient morbidity and poor adherence can also contribute to sub-optimal drug delivery systems outcomes in the elderly. The development of drug delivery systems for the elderly is a poorly realised opportunity, with each system having specific advantages and limitations. A key challenge is to provide the innovation that best meets the specific physiological, psychological and multiple drug requirements of individual elderly patients.

Metabolomics Approach for Validation of Self-Reported Ibuprofen and Acetaminophen Use

Over-the-counter analgesic use is common and is typically assessed through self-report; therefore, it is subject to misclassification. Detection of drug metabolites in biofluids offers a viable tool for validating self-reported analgesic use. Thus, the aim of this study was to determine the utility of a metabolomics approach for the validation of acetaminophen and ibuprofen use in blood samples. Untargeted mass spectrometry-based metabolomics analysis was conducted in serum samples from 1547 women and plasma samples from 556 men. The presence of two metabolites each for acetaminophen and ibuprofen at levels at or above a defined cutoff value was used to determine concordance with self-reported use. For acetaminophen use based on the presence of both acetaminophen and acetamidophenylglucuronide, concordance was 98.5–100% among individuals reporting use today, and 79.8–91.4% for those reporting never or rare use. Ibuprofen use based on the presence of both carboxyibuprofen and hydroxyibuprofen resulted in concordance of 51.3–52.5% for individuals reporting use today and 99.4–100% for those reporting never or rare use. Our findings suggest that an untargeted metabolomics approach in blood samples may be useful for validating self-reported acetaminophen use. However, this approach appears unlikely to be suitable for validating ibuprofen use.

Short-Term Fasting Alters Pharmacokinetics of Cytochrome P450 Probe Drugs: Does Protein Binding Play a Role?

Background and Objectives

Short-term fasting differentially alters cytochrome P450 (CYP) mediated drug metabolism. This has been established by using CYP-enzyme selective probe drugs. However, the observed effects of fasting on the pharmacokinetics of these probe drugs may also include the effects of altered plasma protein binding of these drugs. Therefore, we studied the effect of short-term fasting on protein binding of five commonly used probe drugs [caffeine (CYP1A2), metoprolol (CYP2D6), midazolam (CYP3A4), omeprazole (CYP2C19) and S-warfarin (CYP2C9)].

Methods

The free and total plasma concentrations of the five probe drugs were analyzed by LC–MS/MS in samples retrieved in a cross-over study in which nine healthy subjects received an intravenous administration of the cocktail after an overnight fast (control) and after 36 h of fasting.

Results

Short-term fasting increased plasma free fatty acid concentrations from 0.48 mmol/L (control) to 1.29 mmol/L (36 h fasting) (p = 0.012). Short-term fasting did not alter the free fractions of caffeine, metoprolol and omeprazole compared to the control intervention (p > 0.05). Power to detect a difference for midazolam and S-warfarin was low since the majority of free concentrations were below the limit of quantification.

Conclusions

This study demonstrates that short-term fasting does not alter protein binding of the probe drugs caffeine, metoprolol and omeprazole.

Electronic supplementary material

The online version of this article (doi:10.1007/s13318-017-0437-7) contains supplementary material, which is available to authorized users.

Deprescribing Benzodiazepines in Older Patients: Impact of Interventions Targeting Physicians, Pharmacists, and Patients

Benzodiazepines (BZDs; including the related Z-drugs) are frequently targets for deprescribing; long-term use in older people is harmful and often not beneficial. BZDs can result in significant harms, including falls, fractures, cognitive impairment, car crashes and a significant financial and legal burden to society. Deprescribing BZDs is problematic due to a complex interaction of drug, patient, physician and systematic barriers, including concern about a potentially distressing but rarely fatal withdrawal syndrome. Multiple studies have trialled interventions to deprescribe BZDs in older people and are discussed in this narrative review. Reported success rates of deprescribing BZD interventions range between 27 and 80%, and this variability can be attributed to heterogeneity of methodological approaches and limited generalisability to cognitively impaired patients. Interventions targeting the patient and/or carer include raising awareness (direct-to-consumer education, minimal interventions, and 'one-off' geriatrician counselling) and resourcing the patient (gradual dose reduction [GDR] with or without cognitive behavioural therapy, teaching relaxation techniques, and sleep hygiene). These are effective if the patient is motivated to cease and is not significantly cognitively impaired. Interventions targeted to physicians include prescribing interventions by audit, algorithm or medication review, and providing supervised GDR in combination with medication substitution. Pharmacists have less frequently been the targets for studies, but have key roles in several multifaceted interventions. Interventions are evaluated according to the Behaviour Change Wheel. Research supports trialling a stepwise approach in the cognitively intact older person, but having a low threshold to use less-consultative methods in patients with dementia. Several resources are available to support deprescribing of BZDs in clinical practice, including online protocols.

Genomic Variation and Pharmacokinetics in Old Age: A Quantitative Review of Age- vs. Genotype-Related Differences

Older persons may particularly benefit from pharmacogenetic diagnostics, but there is little clinical evidence on that question. We quantitatively analyzed the effects of age and genotype in drugs with consensus on a therapeutically relevant impact of a genotype. Assuming additive effects of age and genotype, drugs may be classified in groups with different priorities to consider either age, or genotype, or both, in therapy. Particularly interesting were those studies specifically analyzing the age‐by‐genotype interaction.

Analysis of the Variables Influencing Valproic Acid Concentration in the Serum and Cerebrospinal Fluid of Chinese Patients After Craniotomy

BACKGROUND

Valproic acid (VPA) has been widely used in Chinese patients after craniotomy. Many studies have focused on the influencing factors of VPA serum concentration, but conclusions are sometimes paradoxical. Furthermore, the concentration of VPA in the cerebrospinal fluid (CSF) has been rarely reported. In the present study, VPA CSF concentrations were measured, and the potential factors influencing serum concentration and CSF distribution of VPA were investigated. In addition, the functional relationship between serum and CSF concentration was explored.

METHODS

Subjects were patients who underwent craniotomy and were administrated with VPA and had a lumbar puncture. Serum and CSF VPA concentrations were measured by use of the Abbott i1000 system. CYP2C9 (430 C>T, 1075 A>C, 1076 T>C, 1080 C>G), UGT1A6 (541 A>G, 552 A>C), UGT2B7 (211 G>T, 802 C>T), and ABCB1 (1236 C>T, 2677 G>T/A, 3435 C>T) genotypes were determined by direct sequencing. Information, such as age, gender, and height, was collected, and their effect on serum and CSF VPA concentrations was investigated by univariate analysis and multiple linear regression analysis.

RESULTS

First, the concomitant use of carbapenems (β' = -0.422) and UGT1A6 (552 AA → AC) (β' = -0.249) had a significant negative correlation with the weight-adjusted VPA serum concentration (C:W ratio), whereas CYP2C9 (1075 AA → AC) (β' = 0.186) and gender (female compared with male) (β' = 0.322) showed a positive correlation with VPA serum C:W ratio. The coefficient of determination (R) was only 0.348. Second, the relationship between the serum concentration and the CSF square root of the concentration (R = 0.705) had a better linear fit. Third, serum VPA concentration (β' = 0.810), concomitant use of glycerol fructose (β' = 0.160), and age (≥65 compared with <65) (β' = 0.118) showed a positive correlation (R = 0.748) with the variability of square root of the concentration of the CSF.

CONCLUSIONS

In Chinese patients, after craniotomy, female patients with 1 or more of CYP2C9 (1075 AC) and UGT1A6 (552 AA) genotypes required a lower VPA dosage compared with male patient. There was a better-fitted linear relationship between VPA serum and the square root of CSF concentrations. CSF VPA concentrations were relatively stable, with only age and the use of glycerol fructose having a small influence.

Population Pharmacokinetics Modeling of Unbound Efavirenz, Atazanavir, and Ritonavir in HIV-Infected Subjects With Aging Biomarkers

Unbound drug is the pharmacodynamically relevant concentration. This study aimed to determine if chronologic age or markers of biologic aging, such as the frailty phenotype and p16INK4a gene expression, altered unbound pharmacokinetics (PKs) of efavirenz (EFV) and atazanavir/ritonavir (ATV/RTV). Sixty human immunodeficiency virus (HIV)-infected participants receiving EFV and 31 receiving ATV/RTV provided 1 to 11 samples to quantify total and unbound plasma concentrations. Population PK models with total and unbound concentrations simultaneously described are developed for each drug. The unbound fractions for EFV, ATV, and RTV are 0.65%, 5.67%, and 0.63%, respectively. Covariate analysis suggests RTV unbound PK is sensitive to body size; unbound fraction of RTV is 34% lower with body mass index (BMI) above 30 kg/m2 . No alterations in drug clearance or unbound fraction with age, frailty, or p16INK4a expression were observed. Assessing functional and physiologic aging markers to inform potential PK changes is necessary to determine if drug/dosing changes are warranted in the aging population.

Pharmacokinetics and pharmacodynamics of rocuronium in young adult and elderly patients undergoing elective surgery

Objective

To evaluate the impact of advanced age on rocuronium kinetic disposition in ASA I–III patients undergoing elective surgeries.

Methods

Young adult (20–50 years, n = 15) and elderly patients (65–85 years, n = 14) submitted to surgery under general anaesthesia were investigated. All patients were induced with individual intravenous doses of midazolam, rocuronium, fentanyl and propofol. Rocuronium-induced neuromuscular block was monitored by train of four stimulations of the adductor muscle of the thumb on the ulnar nerve. The pharmacokinetic parameters were calculated by non-compartmental analysis. The relationship between rocuronium plasma concentration and the neuromuscular blockade was described by a sigmoidal Emax model.

Key-findings

Elderly patients presented decreased Cl (2.1 ml/kg per min vs 2.8 ml/kg per min; P = 0.0123); increased AUC/dose (507.8 μg min/ml (mg/kg) vs 392.2 μg min/ml/(mg/kg); P = 0.0168) and reduced volume of distribution (285.4 ml/kg vs 435.6 ml/kg, P = 0.0434) compared to young adults. The concentrations required to achieve 50% of maximum neuromuscular block (EC50) were similar for young adult (338.8 ng/ml) and elderly (462.7 ng/ml) patients (P &gt; 0.05).

Conclusions

Elderly patients showed increased AUC/D and reduced total Cl compared to young adult patients due to the age-related reduced renal function. Differences in the PK-PD properties of rocuronium in elderly population are due to changes in drug disposition rather than to alterations in the sensitivity to the drug.

UGT1A6- and UGT2B7-related valproic acid pharmacogenomics according to age groups and total drug concentration levels

AIM

The role of UGT1A6 and UGT2B7 polymorphisms and the impact of total drug plasma concentration in valproic acid (VPA) pharmacogenomics.

PATIENTS & METHODS

A total of 134 Greek patients were recruited (76 adults). Patients were genotyped for UGT1A6 19T>G, 541A>G and 552A>C and UGT2B7 802T>C polymorphisms. Patients' demographic and clinical data were registered. Natural logarithm of concentration-to-dose ratio (CDR) was also calculated as the final outcome.

RESULTS

No significant genotype-related differences in VPA metabolism were noted among various subgroups. An increased lnCDR ratio was noted in children patients compared with adults suggesting increased metabolic capability in younger ages.

CONCLUSION

UGT1A6 and UGT2B7 genotypes were not related to significant changes in VPA metabolism, even after controlling for total drug concentration levels. Younger ages were associated with increased VPA clearance rate.

Age-related loss of hepatic Nrf2 protein homeostasis: Potential role for heightened expression of miR-146a

Nrf2 regulates the expression of numerous anti-oxidant, anti-inflammatory, and metabolic genes. We observed that, paradoxically, Nrf2 protein levels decline in the livers of aged rats despite the inflammatory environment evident in that organ. To examine the cause(s) of this loss, we investigated the age-related changes in Nrf2 protein homeostasis and activation in cultured hepatocytes from young (4-6 months) and old (24-28 months) Fischer 344 rats. While no age-dependent change in Nrf2 mRNA levels was observed (p>0.05), Nrf2 protein content, and the basal and anetholetrithione (A3T)-induced expression of Nrf2-dependent genes were attenuated with age. Conversely, overexpression of Nrf2 in cells from old animals reinstated gene induction. Treatment with A3T, along with bortezomib to inhibit degradation of existing protein, caused Nrf2 to accumulate significantly in cells from young animals (p<0.05), but not old, indicating a lack of new Nrf2 synthesis. We hypothesized that the loss of Nrf2 protein synthesis with age may partly stem from an age-related increase in microRNA inhibition of Nrf2 translation. Microarray analysis revealed that six microRNAs significantly increase >2-fold with age (p<0.05). One of these, miRNA-146a, is predicted to bind Nrf2 mRNA. Transfection of hepatocytes from young rats with a miRNA-146a mimic caused a 55% attenuation of Nrf2 translation that paralleled the age-related loss of Nrf2. Overall, these results provide novel insights for the age-related decline in Nrf2 and identify new targets to maintain Nrf2-dependent detoxification with age.

Pharmacotherapy in the ageing patient: The impact of age per se (A review)

A literature search was carried out to review the influence of 'ageing' on pharmacotherapeutic decision-making, specifically how 'age' is defined and considered in the utilisation of medication. Embase, Medline, International Pharmaceutical Abstracts, and Google scholar were canvassed in a three-tiered search according to pre-established inclusion criteria. In tier 1, a total of 22 studies were identified highlighting the underutilisation of medication in elderly patients, with a particular focus on warfarin. Four studies highlighted an age-bias in medication-prescribing for elderly patients, specifically in relation to medicines for rheumatoid arthritis, angina, and hypertension. Tier 2 identified diverse definitions for 'elderly', including biological age, chronological age, physiological age, as well as various descriptions of 'elderly' in clinical trials and guidelines. Finally, medication optimisation tools were identified through the third tier, emphasising the use of chronological age to describe the 'elderly'. Old age influences pharmacotherapeutic decision-making at various levels, however, what complicates the situation is the absence of a comprehensive definition of 'elderly'. Clinical recommendations need to be based more on objective factors known to affect medication effectiveness and safety.

Understanding alterations in drug handling with aging: a focus on the pharmacokinetics of maintenance immunosuppressants in the elderly

PURPOSE OF REVIEW

This review presents current knowledge of the impact of age on the pharmacokinetics of maintenance immunosuppressants.

RECENT FINDINGS

Over the past decade, there has been a steady increase in older patients on organ transplant waiting lists. As a result, the average age of transplant recipients has significantly increased. The survival and quality-of-life benefits of transplantation in the elderly population have been demonstrated. Advancing age is associated with changes in immune responses, as well as changes in drug handling. Immunosenescence is a physiological part of aging and is linked to reduced rejection rates, but also higher rates of diabetes, infections and malignancies. Physiologic changes associated with age can have a significant impact on the pharmacokinetics of the maintenance immunosuppressive agents. Taken together, these age-related changes impact older transplant candidates and may have significant implications for managing immunosuppression in the elderly.

SUMMARY

Despite the lack of formal efficacy, safety and pharmacokinetic studies of individual immunosuppressants in the elderly transplant population, there are enough data available for practitioners to be able to adequately manage their older patients. A proficient understanding of the factors that impact the pharmacokinetics of the immunosuppressants in the elderly is essential to managing these patients successfully.