Pharmacoepidemiology in older people: Purposes and future directions

Drugs and the elderly: A complex interaction

Although it can be difficult to define who should be considered an elderly person, the population aged 65 and over is experiencing the fastest demographic expansion and will represent almost one billion inhabitants of the 2030 World. Drug use increases dramatically with age and the elderly population is, by far, the highest consumer of medicines, up to 10 times more than younger adults. This consumption is in many aspects inappropriate, unjustified or sub-optimal and associated with a huge number of adverse reactions, admissions in emergency units and attributable deaths. A good part of which could be prevented if basic rules of good prescription and ad-hoc guidelines were systematically used. Even if older adults are more likely to present an adverse drug reaction, available data tend to support that the main risk factor of iatrogenesis in the elderly is the number of drugs used. Moreover, it is often irrelevant to transpose to this population the conclusions concerning the benefit-risk balance of drugs assessed in younger adults; similarly, approaches and programs classically used in pharmacovigilance and pharmacoepidemiology should be tailored to this specific population.

Potentially inappropriate medications in nursing homes and the community older adults using the French health insurance databases

PURPOSE

Potentially inappropriate medications (PIMs) have become a major issue in improving prescribing practices and reducing the risk of adverse drug events in older people. However, very few studies have compared exposition to PIMs controlling for differences in demographic and health between nursing home residents (NHRs) and community-dwelling older adults (CDOAs). This study aimed to assess the prescribing pattern of PIMs between NHRs and CDOAs.

METHODS

We conducted a cross-sectional study over three months in 2019 using the French Health Insurance databases. The study population included 274 971 NHRs and 4 893 721 CDOAs aged 75 years or over. The prevalence ratio (PR) between NHRs and CDOAs of 17 PIM indicators, based on the Beers and STOPP criteria lists, was assessed using multivariable robust Poisson regression adjusted for age, sex, diseases, and polypharmacy.

RESULTS

During the study period, 54% of NHRs and 29% of CDOAs received at least one PIM. After adjustment, the prevalence of PIMs was 33% higher among NHRs compared to CDOAs (aPR = 1.33; 95% CI [1.33-1.34]). NHRs received PIMs related to benzodiazepines (aPR = 1.43; 95% CI [1.42-1.43]), anticholinergic drugs (aPR = 1.29; 95% CI [1.27-1.31]), and at least three central nervous system-active drugs (aPR = 1.94; 95% CI [1.92-1.96]) more frequently. Prevalence of PIMs related to non-steroidal anti-inflammatory drugs (aPR = 0.50; 95% CI [0.48-0.52]) and long-acting benzodiazepines (aPR = 0.84; 95% CI [0.82-0.85]) was lower among NHRs.

CONCLUSION

The NHRs were at greater risk for PIM than CDOAs, although differences exist according to the category of PIMs. As the population is aging, it is essential to promote and evaluate interventions in NHs and the community to enhance medication optimization.

Chronic polypharmacy at all age: A population-based drug utilization study

Polypharmacy is a growing concern often described only in older people by cumulating all drugs taken. We aimed to describe chronic polypharmacy in France, regardless of age. A cross-sectional descriptive study was performed using the 1/97th representative sample of the French health insurance nationwide database (EGB). All subjects alive on January 1, 2015, and covered by the French healthcare insurance were included, and their information collected until December 31, 2015, or date of death. Drug exposures were estimated from drug dispensing dates and treatment durations. Chronic uses of drug were defined as drugs used daily for more than 6 months. Chronic polypharmacy corresponded to the exposure to five chronic uses of drug or more. In 2015, information of 584 862 subjects was collected (mean age: 42.2 years). Prevalence of chronic polypharmacy was 5.6% and incidence 1.1%. Prevalence of chronic polypharmacy increased noticeably from 0.2% for subjects aged 18 to 40 years to a maximum of 29.2% for subjects aged 80 to 90 years and then decreased to 23.6% for subjects aged 90 years and more. Lipid-modifying agents were the most frequent drugs involved in chronic polypharmacy (10% of exposure). According to age, the most important differences between the younger and older people were found for cardiovascular drugs (43.5% vs. 45.7% of exposure, respectively) and nervous system drugs (13.7% vs. 11.5% of exposure, respectively). This population-based study showed increasing of chronic polypharmacy and evolution of chronic drug patterns with age.

Prescription of Potentially Inappropriate Medication in Older Inpatients of an Internal Medicine Ward: Concordance and Overlap Among the EU(7)-PIM List and Beers and STOPP Criteria

Background: Age-related comorbidities prone older adults to polypharmacy and to an increased risk of potentially inappropriate medication (PIM) use. This work aims to analyze the concordance and overlap among the EU(7)-PIM list, 2019 Beers criteria, and Screening Tool of Older Person’s Prescriptions (STOPP) version 2 criteria and also to analyze the prevalence of PIM.

Methods: A retrospective cohort study was conducted on older inpatients of an internal medicine ward. Demographic, clinical, and pharmacological data were collected, during March 2020. After PIM identification by the EU(7)-PIM list, Beers criteria, and STOPP v2 criteria, the concordance and overlap between criteria were analyzed. A descriptive analysis was performed, and all the results with a p-value lower than 0.05 were considered statistically significant.

Results: A total of 616 older patients were included in the study whose median age was 85 (Q1–Q3) (78–89) years. Most of the older patients were male (51.6%), and the median (Q1–Q3) number of days of hospitalization was 17 (13–22) days. According to the EU(7)-PIM list, Beers criteria, and STOPP criteria, 79.7, 92.0, and 76.5% of older adults, respectively, used at least one PIM. A poor concordance (<63.4%) among criteria was observed. An association between PIM and the number of prescribed medicines was found in all applied criteria. Moreover, an association between the number of PIMs and diagnoses of endocrine, nutritional, and metabolic diseases, mental, behavioral, and neurodevelopmental disorders, and circulatory system diseases and days of hospitalization was observed according to Beers criteria, and that with diseases of the circulatory system and musculoskeletal system and connective tissue was observed according to STOPP criteria.

Conclusion: Despite the poor concordance between the EU(7)-PIM list, 2019 Beers, and STOPP v2 criteria, this work highlights the need for more studies in inpatients to develop strategies to facilitate the identification of PIM to decrease the high prevalence of PIM in hospitalized patients. The poor concordance among criteria also highlights the need to develop new tools adapting the existing criteria to medical ward inpatients.

REview of potentially inappropriate MEDIcation pr[e]scribing in Seniors (REMEDI[e]S): French implicit and explicit criteria

PURPOSE

To establish a consensus on both explicit and implicit criteria in order to identify potentially inappropriate prescribing (PIP) in French older people aged 75 years and over or 65 years and over with multimorbidity.

METHODS

Fifteen experts in geriatrics, general practice, pharmacy, and clinical pharmacology were involved in a two-round Delphi survey to assess preliminary explicit and implicit criteria based on an extensive literature review and up-to-date evidence data. Experts were asked to rate their level of agreement using a 5-level Likert scale for inclusion of criteria and also for rationale and therapeutic alternatives. A consensus was considered as reached if at least 75% of the experts rated criteria as "strongly agreed" or "agreed."

RESULTS

The new tool included a seven-step algorithm (implicit criteria) encompassing the three main domains that define PIP (i.e. overprescribing, underprescribing, and misprescribing) and 104 explicit criteria. Explicit criteria were divided into 6 tables related to inappropriate drug duplications (n = 7 criteria), omissions of medications and/or medication associations (n = 16), medications with an unfavourable benefit/risk ratio and/or a questionable efficacy (n = 39), medications with an unsuitable dose (n = 4) or duration (n = 6), drug-disease (n = 13), and drug-drug interactions (n = 19).

CONCLUSION

The REMEDI[e]S tool (REview of potentially inappropriate MEDIcation pr[e]scribing in Seniors) is an original mixed tool, adapted to French medical practices, aimed at preventing PIP both at the individual level in clinical practice and the population level in large-scale studies. Therefore, its use could contribute to an improvement in healthcare professionals' prescribing practices and safer care in older adults.

Methods for evaluating the benefit and harms of deprescribing in observational research using routinely collected data

Deprescribing is defined as "the planned and supervised process of dose reduction or stopping of medication that might be causing harm, or no longer be of benefit". Barriers to deprescribing include healthcare professional fear and lack of guidance. These may stem from limited available evidence on benefits and harms of deprescribing medications commonly used among older persons. Advances in pharmacoepidemiology and causal inference methods to evaluate comparative effectiveness and safety of prescribing medications have yet to be considered for deprescribing medication. This paper discusses select methods and how they can be applied to deprescribing research, using case studies of benzodiazepines and low-dose acetylsalicylic acid (aspirin). Target trial emulation involves the explicit application of design principles from randomised controlled trials to observational studies. Several design aspects, including defining eligibility criteria and time zero, require additional considerations for deprescribing studies. The active comparator new user design also presents challenges, including selection of an appropriate comparator. This paper discusses these aspects, and others, in relation to deprescribing studies. Furthermore, methods proposed to control for confounding, in particular, the prior event rate ratio and propensity scores, are discussed. Introduction of billing codes or mechanisms for accurately determining when deprescribing has occurred would enhance the ability to conduct research using routinely collected data. Although the approaches discussed in this paper may strengthen observational studies of deprescribing, their use may be best suited to certain scenarios or research questions, where randomised controlled trials may be less feasible.

Iatrogenesis and neurological manifestations in the elderly

Older people are often exposed to polypharmacy in a multimorbidity context. Inappropriate polypharmacy is often harmful, increasing the risk of inappropriate prescriptions and therefore adverse drug events (ADEs). Five to 20% of all hospital admissions are related to ADE in older people, among which 40 to 70% could be prevented. However, identifying ADEs and drug-related admissions in the elderly is challenging because ADEs often present as common geriatric problems such as falls, delirium, which might be due to the aging process, underlying diseases, and/or medications. In the pharmacovigilance database of the World Health Organization, drug-related neurological manifestations are the third reported cause of ADEs in the elderly, and neurological drugs are the third leading class of medications involved in ADEs. We must therefore be particularly vigilant, both in our prescriptions but also in our diagnoses to avoid prescribing inappropriate treatments and detect ADEs. Even though multiple pharmacologic changes occur in the elderly (absorption, distribution, drug metabolism and excretion), most of medications are still often prescribed at the same daily dosage as in young adults. When prescribing any drug for old patients, we should remember that daily intake should be adapted to these specificities, keeping in mind the old well-known aphorism "start low, go slow". In this review, we describe the main drug-related neurological manifestations (drug-induced movement disorders, falls, seizures, delirium, hypoglycemia, stroke, hyponatremia, peripheral neuropathy and myopathy, and serotonin syndrome) and the main drugs associated with neurological manifestations (dopamine receptor blocking agents, antithrombotics, anticholinergics, beta-lactams, antidepressants, benzodiazepines, mood stabilizers).