Polypharmacy and Drug Adherence in Elderly Patients

US Pharm. 2019;44(7):33-36.

Polypharmacy and medication adherence in the elderly are significant public-health considerations worldwide and are an important focus of integrated care. Polypharmacy—the use of multiple drugs or more drugs than are medically necessary—causes adherence problems in older patients, particularly those not residing in nursing homes. For this reason, there is an urgent need to address this growing issue in the elderly population. Approximately 44% of men and 57% of women older than 65 years take five or more nonprescription and/or prescription medications per week, and 12% of persons in this age group take 10 or more nonprescription and/or prescription medications per week.¹

It is not unusual for patients with respiratory problems, type 2 diabetes, and existing coronary heart disease to be taking six to nine medications to reduce their long-term risk of further complications and secondary coronary events. In fact, strict adherence to national treatment guidelines for such patients results in a minimum of six concurrent prescription medications. Polypharmacy becomes problematic when negative outcomes occur.¹

A consensus does not exist on the number of medications considered to define polypharmacy, and the number of medications designated as polypharmacy varies among studies. The use of medications that are not indicated, are ineffective, or constitute therapeutic duplication would be considered polypharmacy, and this definition necessitates a clinical review of medication regimens.²

As the population ages, the healthcare system is challenged with an increasing burden of chronic diseases and rising prescription expenditures. This article briefly identifies the prevalence and types of medications taken by older adults with polypharmacy and drug-adherence issues, after which a discussion is presented of the epidemiology of adverse health reactions resulting from polypharmacy and how medication use can be improved.

Drugs and Aging

In general, older people react differently to medications than younger patients react. Although aging does not change the absorption rate of most drugs, it can alter body-fat and water composition. With age, body-fat stores increase while total body water decreases. These are important changes that can alter therapeutic drug levels, resulting in greater concentrations of water-soluble drugs and longer half-lives for fat-soluble medications.¹

Additionally, it should be noted that the liver metabolizes many drugs and that age-related changes can reduce hepatic blood flow and alter drug clearance. Drug elimination may also be affected by age-related decreases in renal blood flow, as well as by changes caused by chronic diseases.¹

Many drugs are bound to plasma proteins so that only the unbound or free portion is biologically active. As a result of aging, serum albumin levels decrease in adults who are experiencing malnutrition or have chronic diseases. This could lead to higher levels of drug in the blood and cause drug toxicity.¹

Polypharmacy in Different Health Settings

As mentioned above, polypharmacy refers to the use of multiple drugs from different pharmacologic categories in various settings. The following sections briefly discuss these settings and their benefits and shortcomings.

Outpatient and Ambulatory Care: Outpatient and ambulatory-care sites come in a variety of models. Many studies in ambulatory care define polypharmacy as a medication count of five or more medications. Current practice guidelines often require multiple medications to treat each chronic disease state for optimal clinical benefit. Therefore, an elderly patient with at least two disease states, such as respiratory disease and diabetes, will usually exceed this arbitrary threshold of more than five medications.³

There are different models of multidimensional care settings. Although there is overlap among the models, each has its own market criteria within the healthcare ecosystem and serves a specific purpose. The following are various models for ambulatory care³:

1. Computers and Internet providers: These give patients easy access to portals and medical websites.
2. Mobile care: As part of charitable outreach programs, vans travel to different locations to provide medical services to communities.
3. Retail clinics: Located in retail drugstores, these clinics are accessible and convenient for simple medical examinations.
4. Urgent-care centers: Such services as general radiography, laboratory testing, and sutures are provided, and extended hours of operation are offered.
5. Freestanding emergency rooms: These settings offer services that fall between those of urgent-care clinics and hospital-based emergency departments.
6. Work-based clinics: These programs can help employees be healthier and more productive in the workplace.
7. Primary care clinics: The focus here is on team care that may include more collaborative medical services for group visits.
8. Specialty care and high-tech centers: These centers offer specialized care with imaging capabilities for pediatric and adult patients.

Each of these models has some overlap with other models in order to serve patients’ varying health and wellness needs and to capture revenue that might otherwise go elsewhere.³

Inpatient and Hospital Setting: Few studies have examined the issue of polypharmacy in hospitalized elderly patients. A study by Hajjar and colleagues assessed two definitions of polypharmacy upon hospital discharge. Among 384 patients studied, 41.4% were taking at least five to eight medications and 37.2% were taking nine or more medications. Overall, 58.6% of patients took one or more unnecessary prescribed drugs.⁴

Nurses and pharmacists have a unique opportunity to help identify patients who are at risk for inappropriate polypharmacy and to educate patients and families about adherence and risk reduction.⁴

Nursing Home Setting: Polypharmacy in nursing homes has been an ongoing concern for the past four decades. In the late 1990s, the Centers for Medicare and Medicaid Services considered this such an important issue that it implemented a quality-indicator measure targeting patients taking nine or more medications. A study using data from the 2004 United States Nursing Home Survey found that according to this quality-indicator measure, 39.7% of subjects had polypharmacy. Notably, the group with the lowest rate of polypharmacy was patients aged 85 years or older (34.8%).²

In this study, the most frequently reported medications in residents with polypharmacy included gastrointestinal agents (laxatives, 47.5%; agents for acid/peptic disorders, 43.3%), psychotherapeutic drugs (antidepressants, 46.3%; antipsychotics or antimanics, 25.9%), cardiovascular drugs (28%), respiratory drugs (12%), and pain relievers (nonnarcotic analgesics, 43.6%; antipyretics, 41.2%; antiarthritics, 31.2%).²

Reducing polypharmacy should be a priority of clinicians working in nursing homes. Clinicians should evaluate each medication for its utility, taking into consideration such factors as the patient’s life expectancy, the care goals, and the length of time until benefits manifest.²

Deprescribing medications in nursing home residents requires a team-based approach involving physicians, pharmacists, and nurses. Discontinuing a medication should involve proper planning, communicating, and coordinating with the patient and the nursing staff. The nursing staff can help monitor the patient for beneficial or harmful effects from tapering or stopping medications. Patients and families can be educated about the dangers of polypharmacy so that they understand that a medication may be stopped if it is causing harm or no longer benefits the patient. In addition, patients and families should be informed that stopping unnecessary medications and adhering to affective medications can reduce costs.^2,5

Adverse Drug Reactions

Polypharmacy has many negative consequences. The increasing use of multiple medications has been associated with greater healthcare costs and an increased risk of adverse drug reactions, drug-drug interactions, medication noncompliance, and multiple geriatric syndromes.⁶

Adverse reactions are common in older adults and often manifest differently than in younger patients. It is reported that an estimated 35% of ambulatory older adults experience an adverse drug reaction each year, and 29% of these reactions require hospitalization. For example, falls, dementia, and urinary incontinence can result from a health problem or a medication.⁶ Common drug classes that are associated with adverse drug reactions include anticoagulants, nonsteroidal anti-inflammatory drugs, cardiovascular medications, diuretics, antibiotics, anticonvulsants, benzodiazepines, and hypoglycemic agents.⁶

The probability of a drug-drug interaction increases with the number of medications being taken. For example, a patient taking five to nine medications has a 50% probability, whereas the risk increases to 100% when a patient is found to be taking 20 or more medications. Therefore, practitioners should keep in mind the possibility of a drug-drug interaction when they are prescribing any new medications to patients.⁶

Poor adherence to the medication regimen is an ongoing problem among older adults. Forgetfulness, decreased vision, and poor manual dexterity may also contribute to this problem. Some patients may attribute unpleasant symptoms to a medication and decrease the dosage or even stop taking the drug without consulting the physician. Financial problems may have an effect on noncompliance.^6,7

Cognitive impairment, which occurs with both delirium and dementia, has been associated with polypharmacy. Patients taking five or more medications have been reported to have impaired cognition.⁷

Falls are associated with increased morbidity and mortality in older adults and may be precipitated by certain medications. Given the serious consequences of falls in older adults, caution should be used in prescribing new drugs to patients who are at risk of falling.⁷

Urinary incontinence is another condition that is associated with the use of multiple medications. Many medications are known to exacerbate urinary incontinence, so a review should be performed to evaluate both the number of medications and the specific types of medications a patient is taking.⁷

Additionally, polypharmacy has been reported to have effects on a patient’s nutritional status. In older adults, polypharmacy has been associated with a reduced intake of fiber, fat-soluble and B vitamins, and minerals, as well as with an increased intake of cholesterol, glucose, and sodium.⁷

Healthcare Providers’ Role in Reducing Polypharmacy

Nurses and pharmacists in hospitals and nursing homes can be pivotal in helping older patients manage their medications and prevent polypharmacy. For instance, knowing that a patient has end-stage renal disease allows the pharmacist to determine that the prescribed metformin is not appropriate for that particular patient. Linking each prescribed medication to a disease state or diagnosis will make that medication potentially necessary. There are three major keys to reducing polypharmacy risks^5,8,9:

1. It is important to talk with patients about keeping an accurate list of all medications, including the prescribed dosage, the dosing frequency, and the reason it was prescribed. Discuss with the patient any dietary restrictions necessitated by a specific medication. Inform the patient about potential side effects, and provide information about look-alike and sound-alike medications. These face-to-face meetings are invaluable and facilitate strong relationships with patients.
2. Instruction and good communication are vital. Primary care providers and specialists must maintain good communication with each other and with patients in order to minimize problems and maximize adherence. Patients should be advised to take medications based on the instructions the prescriber gave them and not to stop taking a medication before consulting the prescriber. At every office visit, the patient should be asked about his or her adherence to the medication regimen and use of all OTC preparations.
3. Organization can improve compliance. Patients should be advised not to share their medications or save them for future use. Medications should be stored in a secured place. Color-coded pillboxes or blister packs can help elderly patients adhere to their regimen. One useful reminder method for patients with cognitive deficits involves basic techniques like linking dosing schedules to routine daily activities, such as brushing the teeth, eating breakfast, or performing other memory-trigger activities.

Conclusion

Polypharmacy is common among elderly persons because of the need to treat the various disease states that develop with age. Although the deprescribing of unnecessary medications is a way of limiting polypharmacy, the underprescribing of effective therapies in older patients is a concern. Therefore, healthcare providers must evaluate each drug and balance its potential adverse effects against its potential benefits. Advances in information technologies such as electronic prescribing, electronic medical records, and electronic laboratory results will help prevent adverse drug effects and interactions. Medication management in nursing homes and outpatient settings is feasible because of alterations in administration and technology-driven prescribing systems.

REFERENCES

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6. Shah BM, Hajjar ER. Polypharmacy, adverse drug reactions, and geriatric syndromes. Clin Geriatr Med. 2012;28(2):173-186.
7. Forster AJ, Murff HJ, Peterson JF, et al. The incidence and severity of adverse events affecting patients after discharge from the hospital. Ann Intern Med. 2003;138(3):161-167.
8. Dwyer LL, Han B, Woodwell D, Rechtsteiner EA. Polypharmacy in nursing home residents in the United States: Results of the 2004 National Nursing Home Survey. Am J Geriatr Pharmacother. 2010;8(1):63-72.
9. Antonelli Incalzi R, Pedone C, Pahor M. Multidimensional assessment and treatment of the elderly with COPD. Eur Respir Monogr. 2009;43:35-55.

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