Potentially inappropriate medication prescribing in older adults: American geriatric society updated beers criteria journey

Rishabh Sharma; Parveen Bansal; Ravinder Garg; Malika Arora

doi:10.4103/jiag.jiag_2_21

REVIEW ARTICLE

Year : 2021 | Volume : 17 | Issue : 1 | Page : 28-35

Potentially inappropriate medication prescribing in older adults: American geriatric society updated beers criteria journey

Rishabh Sharma¹, Parveen Bansal², Ravinder Garg³, Malika Arora⁴
¹ Department of Pharmacy Practice, Indo Soviet Friendship College of Pharmacy, Moga, Punjab, India
² University Centre of Excellence in Research, Baba Farid University of Health Sciences, Faridkot, Punjab, India
³ Department of Medicine, Guru Gobind Singh Medical Hospital, Faridkot, Punjab, India
⁴ Multi-Disciplinary Research Unit, Guru Gobind Singh Medical College and Hospital, Faridkot, Punjab, India

Date of Submission	24-Jan-2021
Date of Decision	24-Jan-2021
Date of Acceptance	08-Jul-2021
Date of Web Publication	17-Aug-2021

Correspondence Address:
Dr. Malika Arora
Multi.Disciplinary Research Unit, Guru Gobind Singh Medical College and Hospital, Faridkot, Punjab
India

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jiag.jiag_2_21

Abstract

The present manuscript highlights Beers guidelines till date and puts them at a single platform to enable the physicians, academicians, and patients for the safe and timely use of medicines. Potentially inappropriate medications (PIM) are medications in which adverse risks exceed its health benefits. Complex and multiple comorbidities in older adults make them use multiple drugs that further become a reason for exclusion from randomized clinical trials (RCT). Hence, no set guidelines or RCT-based scientific shreds of evidence are available to support prescription decisions. PIM has become an increasingly common problem in older adults; hence the American Geriatric Society updated Beers criteria; the most crucial strategy to check its use/misuse. The Beers criteria have been formulated in 1991 with the help of validated and appropriate screening tools that explain the use/avoidance of various drugs in older adults based on their health status and are being further updated as and when required. This change in Beers criteria is due to some limitations in the study population, emerging adverse drug reactions/new drug molecules, change in pharmacodynamics of medicines with changing physiology of older adults. Beers guidelines are being updated; however, few significant issues that are not being touched by the committee responsible for constituting the criteria.

Keywords: American Geriatric Society, older adults, potentially inappropriate medication, randomized controlled clinical trials

How to cite this article:
Sharma R, Bansal P, Garg R, Arora M. Potentially inappropriate medication prescribing in older adults: American geriatric society updated beers criteria journey. J Indian Acad Geriatr 2021;17:28-35

How to cite this URL:
Sharma R, Bansal P, Garg R, Arora M. Potentially inappropriate medication prescribing in older adults: American geriatric society updated beers criteria journey. J Indian Acad Geriatr [serial online] 2021 [cited 2023 Mar 21];17:28-35. Available from: http://www.jiag.com/text.asp?2021/17/1/28/323940

Introduction

Defining the elderly is difficult. The older adults are defined as the population who are older than 60 years. Chronologically, the age of 60 years is considered as a definition of “elderly.” Inappropriate medication use is becoming an increasingly common problem in older adults. PIMs are those medications whose adverse risks exceed its health benefits.^[1],[2] Adverse risks of medications and drug-related problems can have safety consequences for older adults and can affect the health care system economically.^[3] It is pertinent to mention that most older adults have complex and multiple comorbidities and are supposed to be on polypharmacy (5–9 medications per day), due to which older adults are mostly excluded from randomized clinical trial.^[4] As a result, prescribing decisions made in the older adults have the absence of scientific evidence generated by rigorous randomized controlled trials. PIMs continue to be prescribed as a first-line treatment on a daily basis, especially in India and other countries. Adverse drug events (ADEs) and drug-related problems in older adults are mostly due to the rapidly increasing use of PIMs in older adults.^[5]

In older adults, several physiological changes occur due to aging. Due to age-related physiological changes, the risk of ADE and drug-related problem keep on increasing as compared to healthy age group patient. Hence, many factors need to be considered while prescribing medications in older adults. In the older adults, age-dependent alteration in drug pharmacokinetics such as changes in drug absorption, distribution, metabolism, and excretion. Age-dependent pharmacodynamics changes cause alterations in the quantity and quality of target drug-receptor and age-related changes in body composition and physiology.^[6] Age-related changes in drug pharmacokinetics and pharmacodynamics make prescribing in older adults more challenging. Keeping in view the above-said issues, the American Geriatrics Society (AGS) keep updating the Beers criteria that were designed to determine the use of potentially inappropriate medication (PIM) in older adults as well as to decrease ADEs and drug-related problems in the older adults. The factors challenging drug therapy in older adults are as follows:

Pharmacokinetics Changes in Older Adults

Absorption

In the older adults, drug absorption altered with the decrease in gastric emptying, decrease in gastrointestinal blood flow, and reduced gastric acidity. Inhibition in first-pass metabolism is already reported for drugs such as propranolol, nitrates, and verapamil.

Distribution

The distribution of drugs in the body mainly depends on plasma and tissue binding characteristics of the drug.

Age-related structural and composition changes are also observed in the older patient, and they can affect the disposition of the drug in many different ways. Increase in body fat and decrease in lean body mass are the most critical structural and composition changes that occur in older adults.

The volume of distribution for water-soluble drugs such as ethanol, lithium, and digoxin decreased with alteration in body mass and body fat.^[7],[8] Alteration in these factors may also lead to an increased volume of distribution of lipid-soluble drugs such as a long-acting benzodiazepine. Drugs dosing in these patients should be carefully designed and monitored as these drugs have the potential to cause adverse effects by increasing the plasma concentration of a drug.

Metabolism

Several age-dependent changes such as the reduction in hepatic size and hepatic blood flow also lead to decreased levels of drug-metabolizing enzymes. Cytochrome 450, one of the most essential metabolizing enzymes, generally declines with aging. Most important factor is to recognize the drug-drug interaction especially involving these enzymes, for example, some drugs which have a first-pass effect in the liver such as beta-blockers, nitrates, and tricyclic antidepressant were found to be effective even at lower doses.^[9] Besides, certain drugs and foods cause induction of liver enzymes resulting in faster metabolism of some other drugs. In contrast, some of the drugs may reduce the action of the liver enzymes and hence resulting in slow metabolism of some other categories of drugs such as enzyme inhibitors. This factor is a crucial factor that plays a vital role in older adults taking multiple medications at the same time.

Excretion

Kidney is mainly involved in the elimination of most of the drugs from the body. The aging causes a decrease in the size of the kidneys in older adults. Aging process cause a significant decrease in renal plasma flow and glomerular filtration rate.^[10] Other age-related factors are the loss of tubular function and diminished reabsorptive capacity. Renal blood flow and the glomerular filtration rate decreases on an average of 35% in older adults having an age 70 years. In such a position, the older adults considered to be at high risk of adverse renal effects due to consumption of NSAIDs. Furthermore, renal vasodilator prostaglandins such as NSAIDs may result in further nephrotoxicity.^[11]

Pharmacodynamic Changes in Older Adults

Pharmacodynamics changes occur in older adults during aging, which mainly includes alteration in receptor number, receptor affinity, post-receptor changes, and age-related alteration. Beta-blocker sensitivity decreases along with a possible decreased clinical response to Beta-blockers and Beta-agonists.^[12],[13] Chronic medications become unsafe or ineffective if changes in patient medical status occur over time. Particular care must be devoted while determining drug dosages and prescribing medication to older adults and chronic patients.^[14]

Polypharmacy

One of the significant challenges in prescribing for older adults is polypharmacy, i.e., the use of multiple medicines at the same time.^[15] Most of the times older adults are consuming multiple drugs to treat their chronic diagnosis. However, increase in adverse drug reaction (ADR), drug-related problems are directly associated with polypharmacy. Older adults who tend to be on polypharmacy show non–specific symptoms such as depression, falls, constipation, light-headedness, confusion, lethargy.^[16] Hence, it becomes difficult to detect ADR in older adults. The ADR rate in older adults is at least three times that of the general population.^[17]

Various physiological changes occurring due to the aging has made the base of the Beers criteria. Hence, keeping all the above-said points in mind, the Beers criteria were formulated with the help of validated and appropriate screening tools and hence become an essential global tool for recommending the use/avoidance of various drugs in older adults based on their health status. The present article has been compiled to highlight the following parameters:

Chronological development of Beers criteria
Salient Features of time-to-time updates of Beers criteria from 1991 to till date
Strengths of Beers criteria
Limitations of the Beers criteria.

The present article will serve as a great help for health care professionals while prescribing medication for older adults in rationalized manner. These are the most necessary and commonly used guidelines for having a check on inappropriate medications. Besides, all the Beer's guidelines are compiled on a common platform to enable the physicians, academicians, and patients for the safe and timely use of medicines as well as for future suggestive consolidations.

Historical perspective and development of Beer's criteria

The consensus technique was used in the development and validation of Beers criteria. Team of experts from the different specialized field such as geriatric medicine and pharmacology was involved in the development of a consensus statement. Literature reviews with a bibliography and a questionnaire evaluated using modified Delphi technique as a basis of consensus development.^[18] The modified Delphi technique has been used first time in 1991 Beer's criteria. The Delphi technique is a beneficial and structured communication technique to formulate a group judgment for a subject matter in which precise information is lacking (such as medication use in older adults). The chronological development of Beer's criteria is described in [Figure 1].

Figure 1: The chronological development of Beers criteria

Click here to view

The criteria were updated and revised time to time, keeping the market of the suggested medicines in mind. Some of the medications were excluded in the revised versions due to the exclusion of drugs from the market. Similarly, some of the medicines are included as many new medications may enter the marketplace that was not considered during the initial development process or in previous updates. Apart from the market analysis, new scientific information may become available about the effects and side effects of particular medications in older adults based on pharmacovigilance reports or drug alert lists issued by the governments/regulatory authorities.

Beer's Criteria 1991

In 1991, Beers et al. published the first set of explicit criteria for determining inappropriate medication use in older adults.^[19] The first published Beers guidelines had focused on older adults residing in nursing care. While working upon the criteria, two rounds of written surveys were conducted, based on the Delphi method.^[20]

Based on factors derived from the literature review, 43 survey questions included in the first-round survey. Twenty-six of the questions addressed medications that should be avoided, and 13 addressed dose, frequency, or duration factors. From the same, the expert panel had produced a list of 30 medications that should be avoided in nursing home residents. The Beer's criteria 1991 had published two general aspects that should be considered while prescribing the medication in older adults which are as follows:

Individual medications or categories of medications that should be avoided (except under unusual clinical circumstances)
Doses, frequency, or duration of medication prescriptions that generally should not exceed as given in the Beer's criteria. The name of medicine along with its permissible medication dose, frequency, duration of dose.

Beer's Criteria 1994

In 1994, Stuck et al. modified Beer 1991 criteria for community-dwelling older adults inappropriate prescribing as the original criteria were limited to nursing home residents.^[21] The goals of the updated criteria were as follows:

For community-dwelling older adults to generate explicit criteria of inappropriate drug use
To determine the prevalence of inappropriate drug use in older adults
To determine different subsets of older adults at high risk for inappropriate medication therapy.

For designing the criteria, 1994, two rounds of consensus were made. The panellists used 5-point Likert scale for rating the appropriateness of use of each drug. Multivariate logistic regression approach was used for calculating the prevalence of a population using a PIM.^[22] Multivariate regression used subject characteristics such as depression score, activities of a daily living score, age, number of self-reported chronic health conditions, gender. According to Beers criteria 1994, inappropriate medications were prescribed in 14% of the subjects. The most common PIMs were long-acting benzodiazepines, dipyridamole, amitriptyline, chlorpropamide. [Figure 2] represents the distribution of prevalence of PIM use in patients according to their gender.

Figure 2: The distribution of prevalence of potentially inappropriate medication use in elderly patients according to their gender^[21]

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In addition to it, during the development of criteria 1994, the panellists reviewed and analyzed the commonly used prescription medications in separate sex and common prescription details in different age groups.

Furthermore, it was revealed that subjects using three or more prescription drugs (in comparison to one or two) were more likely to be taking inappropriate medications in different sex, as well as different age groups, and the persons who were depressed, had a higher risk of receiving inappropriate medication than the person who was not depressed.^[23],[24] On the line of the above points, the criteria 1994 had introduced minor changes in the previously mentioned medication list. In addition, the criteria had highlighted the prevalence of various medications concerning age and gender.

Beer's Criteria 1997

In 1997, Beer's criteria were updated to provide a revised and more comprehensive set of explicit criteria.^[25] Beer's criteria were updated to determine potentially inappropriate drug use in ambulatory people aged 65 years and over. The revised and updated Beer's criteria can be applied to all older adults regardless of their place of residence (community or nursing home) or level of frailty. The significant goals of this update were as follows:

To reformulate the criteria concerning new drugs available in the market and to incorporate new information related to such drugs
To generalize the criteria to a population of persons older than 65 years regardless of their level of frailty or their place of residence
To assign a relative rating of severity caused due to any inappropriate medications
To specify the additional alerts that apply to specific diagnosis and when clinical information of the patient is available.

For validation of updated Beer's criteria, the same but modified Delphi consensus method was used. As a result, the six-panel of experts were enabled to classify potentially inappropriate drugs into three categories which are as follows:

Medications or medication categories that should generally be avoided because they pose an unnecessarily high risk for older adults
Drugs that exceed a maximum recommended daily dose
Drugs to be avoided in those patients who were having specific comorbidities.

Beer's criteria 1997 had explained the classes of medications that should be avoided in older adults based on diagnosis and independent to diagnosis. As a response, 26 medications were identified in Beer's criteria 1997. Out of the 14 were considered highly severe independent to diagnosis. Fifteen medical conditions were identified, for which 35 drug/categories of drugs are considered to be inappropriate in older adults. The list of drugs mentioned in 1997 guidelines along with its severity index. The list of drugs (that may cause high severity) to be avoided older adults with specific disease conditions covered in 1997 Beer's Criteria.

Beer's Criteria 2003

In 2003, Beer's guidelines were updated again and validated by a consensus technique.^[26] The update was done due to lack of a precise information in the previous criteria and to reformulate the criteria for further use of safe medication in older adults.^[27] The guidelines were introduced with appropriateness indexes along with a list of specific drugs that need to be avoided in older adults.^[28] Apart from the consensus technique, systemic review of the evidence-based literature on medications used in older adults was another approach. Still, in older adults' number of controlled studies on medication use was limited. There were 3 main aims to cover in Beer's criteria 2003, which are as follows:

To reformulate the 1997 criteria with respect to new drugs available in the market and to incorporate new information related to such drugs
To assign or reformulate a relative rating of severity for each of the medications
To identify patients with a new condition or existing indication not covered in the 1997 criteria.

The Beer's criteria 2003 was critically reviewed and designed on the basis of two types of statements which are as follows:

Considering inappropriate medication or medication classes that should be avoided in older adults of 65 years or older (independent to diagnosis) because these inappropriate drugs may pose an unnecessarily high risk and especially when an equally effective safer alternative is available
Consideration of the medications that should not be used in older adults having specific medical conditions (dependent of diagnosis).

As a result, 48 individual medications/classes of medications were identified, which are to be avoided and have potential concerns in older adults. Furthermore, 20 diseases/conditions were identified in which some specified medications should be avoided in older adults based on diagnosis. Moreover, the 2003 criteria also had introduced the severity index concerning to adverse outcomes of high severity, 66 drugs were identified and mentioned. Conditions and diagnosis such as cognitive impairment, depression, Parkinson disease, malnutrition, syndrome of inappropriate antidiuretic hormone secretion and obesity were addressed in the criteria.

Salient Features of Beer's Criteria 2012

In 2012, Beer's criteria were updated using a comprehensive, systematic review.^[29] AGS played a crucial role in this Beer's criteria update. Once again in the updated 2012 Beer's criteria Modified Delphi method has been used by the interdisciplinary panel of 11 experts to reach a consensus. The expert panel reached on consensus with the help of systematic review and grading of the evidence on drug-related problems as well as keeping ADEs in mind that is occurring in older adults.

In 2012 criteria, PIMs were categorized into three categories which are as follows:

PIMs/classes to be avoided in older adults: Independent of diagnosis
PIMs/classes to be avoided in older adults with certain diseases (dependent on diagnosis/syndromes)
Medications to be used with caution in older adults based on lab reports and diagnosis as well.

In 2012 Beer's Guidelines, various focus areas covered are as follows:

The 2012 criteria were intended to use in all kinds of ambulatory and institutional setting of care for the population aged 65 and older in the US^{[30],[31],[32]}
The AGS mainly focuses on different ways to improve appropriate prescribing in older adults, drug utilization pattern in older adults, educating health care professionals on appropriate drug use, improve quality of care, improve health outcomes.

For framing Beers criteria 2012, a well-tested framework was used for the development of clinical practice guidelines.^{[33],[34],[35]} In 2012, 53 medications/classes encompassed included in the guidelines, and these were further divided into three categories. Drugs such as glyburide, sliding scale insulin, and thiazolidinediones were notable new inclusions in the independent of diagnosis category. In contrast, glitazones with heart failure, selective serotonin reuptake inhibitor with falls and fractures, acetylcholinesterase inhibitors with a history of syncope were notable new inclusions in the considering diagnosis category. In addition to the new drugs, new components added were quality of evidence and strength of recommendation to each medication.

Salient Features of Beer's Criteria 2015

AGS once again updated Beer's criteria in 2015 for the PIM in older adults.^[36] An interdisciplinary panel of 13 experts from the different specialized field such as experts from geriatric care and pharmacotherapy was involved. Experts used a modified Delphi method for updating the Beer's criteria and to reach a consensus in each existing and new criterion with the help of systematic review and provide grading of each evidence. Evidence1-1 based approach using the institute of medicinal standards was followed.^[37] Some strategies were made to achieve the following aim:

To update evidence obtained from new medication or new indication of old medication not addressed in 2012 Beer's criteria
To provide new evidence on existing PIMs
To assimilate new areas of evidence on drug-drug interactions
To assimilate new areas of evidence on dose adjustment according to kidney function for select medications
Grade the strength and quality of each PIMs statement based on the level of evidence and strength of recommendation
To incorporate exceptions in the criteria that would generally design to make the criteria more individualized to clinical practice and will be more applicable and useful across different settings of care.

The criteria were developed to educate clinicians and patients about PIMs, to improve medication selection, reduce ADE and drug-related problems, decrease hospitalization and improve quality of care in older adults.

In this new update, for the development of clinical practice guidelines for the development purpose, the AGS employed a well-tested framework.^[38] To improve drug safety in older adults: (1) Medication or medication class whose dosage should either be adjusted/reduced according to creatinine clearance level of the patient (2) Clinically relevant Drug-drug interactions that generally should be avoided in older adults.

Two new categories of medication included, and if compared with the 2012 update, the 2015 update has fewer changes in other categories. Only three medications were added, and most importantly, two new inappropriate medication classes were added, but these changes were pervasive. Several drugs were modified or changed based on the rationale and recommendation statements. Some most significant changes were the 90-day used caveat being removed from nonbenzodiazepine, benzodiazepine receptor agonist hypnotics, resulting in an “avoid” statement (without caveats) because of the increase in the evidence of harm in this area since the 2012 update.^[39],[40] In the previously discussed Criteria's some of the statements were given to “avoid” some particular prescription. Still, in the present Criteria, such statements were modified in context to their use or clarified in a better way concerning their use, dose, frequency, duration of action. The change in creatinine clearance level of nitrofurantoin states that nitrofurantoin should be avoided to <30 ml/min from <60 ml/min. Antiarrhythmic drugs classes 1a, 1c, and III (exception of amiodarone) should not be used as first-line treatment for atrial fibrillation. The most important notable change in the considering diagnosis category was the removal of constipation.

Some crucial additions in the 2015 criteria were the (1): Addition of long-term proton pump inhibitor (PPI) in the independent of diagnosis category and use of PPI should generally be avoided in the absence of a firm indication because they have the potential to cause fractures, bone loss as well as the risk of Clostridium difficle Infections may exist.

(2): Older adults with a history of falls and fractures the Beer's criteria states that opioids should be avoided in these patients. If opioids must be used, it is recommended not to use with other CNS-active medications or their dosage should be reduced.^[41]

(3): Another most essential change in the rationale and recommendation for the use of antipsychotics in dementia and delirium drug-disease, drug-syndrome category.

(4): Antipsychotics should be avoided as first-line treatment in patients with delirium as increasing evidence of harm associated with antipsychotics and conflicting evidence on their effectiveness in delirium and dementia.^[42]

(5): Medications with strong anticholinergic properties have been updated. Anticholinergic medication use in older adults remains a concern because it is associated with impaired cognitive and physical function and risk of dementia.^[43],[44]

Salient Features of Beer's Criteria 2019

AGS updated the Beer's criteria for PIM use in older adults in 2019. The modified Delphi method was used by an interdisciplinary panel of experts to reach a consensus on the statement. In 2015 Beer's criteria, The Strategies that are intended to achieve aim and objective in Beer's criteria 2015 were also intended in Beers criteria 2019. No Major changes were observed in the intentions of the criteria. Each of the five types of PIMs categories in the 2015 update was retained in this 2019 update:^[45]

Compared with 2015 criteria, the 2019 update has several vital revisions.

The changes in updated 2019 Beer's criteria are not as extensive as those observed in 2015 Beer's criteria. Significant noteworthy additions include nearly about 70 modifications to the previous 2015 AGS Beer's criteria. Anticholinergic drugs tables again updated in Beer's criteria 2019. Fewer new medications were added, and some medications were modified or removed in a new update. Other notable changes include the addition of new medications, clarifications of criteria language and rationale, and the addition of selected drug-drug interactions. Four new medications or medication classes added to the drug list that should be used with caution. Dextromethorphan/quinidine, Trimethoprim-sulfamethoxazole, Rivaroxaban, Lowering the age threshold in aspirin for primary prevention. One of the most significant changes is addition of two antibiotics, ciprofloxacin, and trimethoprim-sulfamethoxazole, over concerns of increased central nervous system effects and tendon rupture, and worsening renal function and hyperkalemia. From the dependent of diagnosis category, serotonin-norepinephrine reuptake inhibitor was added to the list of drugs to avoid in patients with a history of falls and fractures. The comparative analysis of components covered in Beer's criteria 1991–2019 is described in [Table 1].^[45]

Table 1: Comparative analysis of components covered in beer criteria 1991–2019

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Limitations of Beers criteria

In under-developed and developing countries significant chunk of the people is dependent upon Traditional/Chinese/Ayurvedic/Herbal preparations. However, no such medicine is covered in Beer's guidelines
Aphrodisiacs such as Viagra (Sildenafil citrate) have some adverse effect like altered blood pressure, palpitation, and tachycardia and hence is contraindicative beyond a specific age, especially in older adults
Specific earmarked geriatric health care centers should be opened for better care on a daily basis. Medical Officers posted in nursing homes should seek mandatory training for implementing the Beer guidelines in their day-to-day practice. Moreover, standard operative procedures/protocol should be designed to handle older adults
In addition, grassroots level physicians should know the criteria. Hence, they must undergo mandatory training after a specific period of time as AGS updates the Beer's guidelines time to time as per the requirement of the older adults as well as keeping the changing trends of the pharmaceutical market in mind
No directions have been issued to regulatory authorities as well as universities so that they could recommend its inclusion in under-graduation (MBBS/BAMS/BHMS) as well as post-graduation (MD/MS) curriculum. In addition, it should be included in the curriculum of the professional courses like Pharm. D., nursing, RMPs, Physiotherapists, other health courses where people are entitled to prescribe medicine, etc., who are providing bedside assistance to the patient
World Health Organization should work upon the global implementation of the Beer's guidelines. Moreover, geriatrics societies of the various countries should play a role in its implementation
Directions may be issued by the drug regulatory authority to manufacturers so that while manufacturing they may put warning alerts on the labels of the drugs that are mentioned in the alert list of Beer's criteria as “not safe for the use in age >65” or “Not to be used in older adults.”

Acknowledgment

The authors are thankful to Baba Farid University of Health Science, Faridkot, Punjab, India, and Indo-Soviet Friendship College of Pharmacy for providing the authors with all the necessary facilities and timely guidance.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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