Polypharmacy may be harmful and is a topic attracting increased interest among healthcare providers, especially those who work with older adults. Although adults age 65 and older comprise only approximately 13% of the population, they consume nearly one third of all prescriptions dispensed (Vincent & Velkoff, 2010). Approximately 42 cents of every dollar spent on pharmaceuticals is serving the older adult, which accounts for roughly $100 billion a year. (McCloskey, 2000; Sloan, 2012). Older adults receiving home healthcare take an average of eight medications daily and nearly 40% of them use nine or more drugs (Hayes et al., 2007). Older adults afflicted by polypharmacy are more prone to adverse drug reactions (ADRs) and drug-drug interactions due to physiological changes and multiple comorbidities. Ziere et al. (2006) found that the use of four or more drugs significantly adds to the risk of falls in older patients. Budnitz et al. (2011) found that 37.5% of emergency room visits attributed to adverse drug reactions in adults 65 years or older from 2007 to 2009 resulted in hospitalization. Viktil et al. (2006) found that there was a linear relationship between the number of medications a patient takes and the incidence of drug-related problems. Polypharmacy hurts people. The home healthcare nurse can play an important role in helping to recognize and treat this iatrogenic disease. Nurses can partner with patients and providers to work toward management of polypharmacy.

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Case Study

Across the spectrum of healthcare, there are various definitions of the term polypharmacy. Bushardt et al. (2008) performed a literature review of the various definitions of polypharmacy. The purpose of this study was to create a consensus definition. The authors concluded there was too much ambiguity and chose to use two common definitions: the use of six or more medications and the use of at least one potentially inappropriate medication (based on the Beers list from 2003). Another common definition was the medication does not match the diagnosis. As one can quickly observe, there are a wide range of definitions used to identify polypharmacy, further complicating its identification.

For the purposes of this article, the authors will use Lee's (1998, p. 142) definition. He states that polypharmacy is when "more medications are used or prescribed than are clinically indicated" (Carlson, 1996; Lee, 1998; Montamat & Cusack, 1992). This means that even if a patient is on one medication that is not indicated, it would be polypharmacy. A patient may also be on a medication regimen of 15 drugs that are all indicated and not causing adverse effects, meaning this would not be polypharmacy. For a medication to be indicated, the patient needs to have the disease, symptom, or a risk factor for which the medication is targeted to treat and the medication must be appropriate for that individual patient. Appropriateness can be assessed by ensuring the medication is not causing adverse effects to the patient and that the benefits outweigh the risks.

Why Address Polypharmacy?

Polypharmacy needs to be addressed because it causes harm. It hurts people. The people most afflicted by polypharmacy are often fragile and vulnerable-older adults. One study (Bootman et al., 1997) reported that for every $1 spent on medications, $1.33 was spent on treating drug-related problems. As a pharmacist and someone who handles medications, this plagues me. Polypharmacy is iatrogenic-a disease that is a result of medical treatment-therefore something we are causing as healthcare providers, something we need to work toward avoiding.

Spending for direct-to-consumer advertising nearly doubled from 1996 to 2000 according to Rosenthal et al. (2002). The United States is one of two countries, along with New Zealand, that allow this form of advertising. Although stronger regulations have been put in place to monitor the type of advertising allowed, this strong form of promotion of medications is still concerning. Patients can now learn from advertising what they should "speak with their doctor about" in order to treat many ailments they have. This has the potential to increase the overuse of medications and polypharmacy.

Along with a push to use evidence-based guidelines in medicine, there is a focus of using quality indicators to measure the quantitative quality of healthcare. Lee and Walter (2011) identify that by 2030, adults 65 years and older will represent 20% of the U.S. population and 50% of healthcare costs (Vincent & Velkoff, 2010). Based on this prediction, the older adult will represent the "average" patient.

The emphasis on providing evidence-based medicine provides a significant challenge when caring for older adults. When caring for older adults, healthcare providers must navigate what may be known as an "evidence-free zone." As people age, they are more likely to have multiple comorbidities, which in turn leads to less guidance when choosing treatment measures. In the absence of specific guidance from evidence, data are extracted, often inappropriately, and applied to the older adult patient. This may lead to grave amounts of polypharmacy. Boyd et al. (2005) address the challenge of using practice guidelines in older adults with multiple comorbidities and the impact this has on the quality of healthcare they receive. There are many other contributing factors such as polyprescribing, greater utilization of specialists, direct-to-consumer advertising, and longer life expectancies, leading to more chronic disease states (Rosenthal et al., 2002). These will be discussed in greater detail within this article.

Polypharmacy may lead to a decreased quality of life. Polypharmacy can lead to ADRs, falls, and compliance issues (Sergi et al., 2011). Many studies have found an increase in ADRs with increased medication use. Viktil et al. (2006) found an 8.6% increase in ADRs for each drug increase on a patient's medication regimen. This study was done with patients on admission to an inpatient hospital facility. ADRs accounted for 30% of unplanned hospital admission in 219 patients (75 years and older) in a study conducted by Chan et al. (2001). The patients admitted for ADRs were taking more medications than those admitted for other reasons. Gnjidic et al. (2012) looked at functional outcomes (measured by the Short Performance Physical Battery [SPPB]) of patients 70 years and older living in a self-care retirement community. The authors used Drug Burden Index (DBI), which looks at anticholinergic and sedating medications. For each unit increase in the DBI, there was a 1.7 decrease in the SPPB score, a significant difference. The use of four or more drugs was found to significantly increase the risk of falls in older adults (Ziere et al., 2006).

Budnitz et al. (2011) conducted a study looking at emergency room visits due to ADRs in adults ages 65 and older. An estimated 37.5% of emergency room visits due to ADRs resulted in hospitalization. Almost 50% of the hospitalizations were among patients 80 years or older. The authors identified four medications that accounted for 67% of these hospitalizations: warfarin, insulin, oral antiplatelet medications, and oral hypoglycemic agents. Within this study, they also report the number of medications that patients are taking concomitantly. 40.6% of patients who were hospitalized were between five and nine medications, one of which was implicated in causing an adverse drug effect. This illustrates the glaring harm polypharmacy can cause.

As will be discussed further, many older adults do not present with the common adverse effects associated with medications, but more of an increased "off" feeling or contributions to many of the common geriatric syndromes such as an increase in confusion, urinary incontinence, increased weakness, and changes in sleeping patterns, just to name a few (Sloan, 2012). These can often be passed over as not being a side effect of a medication; however, they can significantly impact a patient's quality of life.

Rossi et al. (2007) bring up another point that is not as widely discussed in the literature or medical community, the health beliefs of the older outpatient. In this study, they identified patients' health beliefs and the relationship this has on polypharmacy. Patients who believe that their health was not determined by a "powerful other" (such as a prescriber or other healthcare provider) were more likely to experience polypharmacy. Patients who did believe their health was determined by their physicians were more likely to request written material about their medications and ask questions. The authors conclude that there is a need for better communication between prescribers and patients to enhance this relationship and work toward shared decision making.

Who Is at Risk?

Older adults are the group most at risk for experiencing polypharmacy. They use nearly one third of prescription medications dispensed, and because of multiple comorbidities many patients are on numerous medications (Boyd et al., 2005). This greater use of medications puts them at a higher risk for having medications that are either not indicated or clinically appropriate.

Transitions of care are identified as another high-risk situation. Forster et al. (2003) reported 20% of patients experience adverse health-related events after being discharged from the hospital to home. Of this number, it is estimated that two-thirds of these are medication related. About 20% of Medicare discharges result in hospital readmissions within 30 days, which costs more than $26 billion per year (Flora et al., 2012; U.S. Department of Health and Human Services, 2011). Patients are often discharged with new or changed medications, which can potentially cause adverse effects not only due to polypharmacy, but also due to medication discrepancies related to this transition (Coleman et al., 2005; Setter et al., 2009). A lack of communication between providers, especially during these times of transition, can further lead to polypharmacy.

Medication Safety Issues

ADRs are a well-known problematic consequence of prescription medications. Unfortunately, they can often be overlooked as something that the patient just needs to "deal with" or passed over as being insignificant by a healthcare provider, when they may have a profound impact on the patient's quality of life. Older adults are especially prone to adverse reactions to medications due to physiological changes of aging altering the effect a medication has in the body. Some of these physiological changes include decreased muscle mass, renal function, and organ reserve capacity making it more difficult for the body to adapt or recovery from injury. These changes can result in medications having more pronounced or longer effect in the older adult. Older adults are, as has been mentioned, more likely to take multiple medications and have multiple comorbidities, further increasing their risk for ADRs. ADRs are one of the leading causes of injury and death in the United States (Peron & Ruby, 2012).

McLendon and Shelton (2012) suggest that possible side effects, or symptoms, should be investigated as drug induced, prompting a medication review. This concept has been written about previously by Avorn (2005) and Gurwitz (2004). This approach can help prevent what is known as the prescribing cascade, further leading to polypharmacy. The prescribing cascade is defined as when a medication is added to treat the side effect of another medication (Rochon & Gurwitz, 1995). This can happen when it is not recognized that the initial medication is causing the side effect; thus, the side effect is viewed as a new symptom or disease and therefore "treated."

Sloan (2012) discusses how often times an older patient will not report a side effect of a medication, but rather a slight worsening of an already present symptom or an overall "off" feeling. According to Sloan, this "off" feeling has been described as anything from increased confusion, falling more frequently, more urinary incontinence, a general malaise, or muscle weakness or fatigue.

One of the biggest challenges when prescribing medications for older adults, as previously mentioned, is that treating older adults needs more age specific evidence. Many randomized controlled studies, the gold standard of research, have been done to show the benefits of medications for patients under the age of 65. Along with a lack of data supporting the use of medications in the older adults, many of the recommended goals used for monitoring therapy, such as blood pressure, cholesterol levels, and blood glucose levels, have not been proven in older adults. In fact, the aggressive treatment of blood pressure, cholesterol, and blood glucose to the standards recommended in younger patients has shown little or no benefit, and in some cases harm, in older adults (Beckett et al., 2008; Brown et al., 2003; Morley, 2011).

Why is there a lack of evidence in this population if they consume such a large percentage of prescription medications? In fact, some clinical trials often exclude older adults (Boyd et al., 2005). Drug trials are designed to eliminate outside factors such as comorbidities and multiple medication use, which could potentially tangle the findings. For this reason, older adults, especially frail older adults, are often excluded from drug trials. However, this is still the population that consumes one-third of medications used, so how are decisions made to put these patients on medications when there is such a paucity of evidence? Data may be often extrapolated by prescribers from studies and then applied to older populations. Although this may be the only evidence or information available in how to use the medication in older adults, is this a safe practice? Many would argue that the data are "stretched too far" when a medication is studied in a younger presumably healthier patient population and then extrapolated and applied in an older and/or frailer population (Boyd et al., 2005). Not only does this raise the question of if a medication is EFFECTIVE if used in this older population, but if that medication is SAFE for use in this older population?

According to Boult and Weiland (2010), the U.S. healthcare system is not conducive to the care of the older adult. The authors illustrate this with a case of an older female struggling to keep up with her own health. A 77-year-old, she has multiple chronic conditions, many medications, and gets around with some difficulty. The authors highlight the challenges she faces with multiple doctors visits to various specialists and how this leads to fragmented and incomplete healthcare. An older patient, such as this one, may spend all their time going from one medical appointment to another, then to the pharmacy for medications, making phone calls to find a specialist who will accept their insurance-all the while not understanding the individual aspects of their care and possibly having some overlooked. This compounded with an insufficient number of providers trained as geriatricians or in geriatrics can lead to poor healthcare, polypharmacy, and poor outcomes.

Guidelines for Medication Use in Older Adults: Three Tools

Because older adults often have multiple comorbidities, many physicians will treat them based on guidelines published (again, sometimes based on studies in younger populations), leading to inappropriate use of medications, or polypharmacy. Boyd et al. (2005) addresses this with a hypothetical 79-year-old patient presenting with five chronic disease states. Following clinical practice guidelines, the patient should be placed on 12 prescription medications. Boyd goes on to address the concerns this presents, primarily from a financial perspective. This raises a concern that Steinman and Hanlon (2010) addressed: finding a happy medium when managing medications in a clinically complex patient. They focus on the steps to finding this happy medium, which will be addressed further in part two of this article. Although Boyd et al. (2005) were primarily focusing from a payer perspective, Steinman and Hanlon (2010) focus on multiple concerns. They address the cost of polypharmacy as well as the high risk for drug side effects, nonadherence, and consequently increased hospital admissions.

Three tools provide limited guidance when prescribing in the older adult population. Although there are other tools available, three are discussed here: (1) the Beers Criteria (American Geriatrics Society 2012 Beers Criteria Update Expert Panel, 2012), (2) the Screening Tool of Older Persons' potentially inappropriate Prescriptions (STOPP) (Gallagher et al., 2008), and (3) the Screening Tool to Alert doctors to the Right Treatment (START) (Barry et al., 2007).

The Beers Criteria are a reference that identifies potentially inappropriate medications (PIMs). It was originally developed in 1991 by a team of geriatric specialists based on expert consensus and has been updated by other groups in 1997, 2003, and 2012. The medications included on the Beers Criteria are divided into three categories: those to avoid in older adults, those to avoid in older adults with certain diseases and syndromes that the drugs listed can exacerbate, and medications to be used with caution. However, caution must be used when applying this information. For example, there are medications listed in the Beers Criteria that are routinely used, appropriately, in hospice patients or others are end-of-life. A complete list of the Beers Criteria can be accessed online at the American Geriatrics Society Web site: http://www.americangeriatrics.org/health_care_professionals/clinical_practice/cl.

STOPP, which was developed in 2008, is a list of PIMs and is organized by physiological systems. This tool is based on an evidence-based, multicenter, multicountry European study conducted in an age-specific population. It addresses drug-drug interactions, drug-disease interactions, medications that will increase a patient's risk of falls, and duplicate drug class prescriptions. When STOPP was compared to Beers Criteria (Hamilton et al., 2011), it was found that STOPP identified significantly more potentially inappropriate medications and it identified twice as many medications that have a relationship to hospital admissions, in the population studied (Table 1).

Table 1.

START was developed in 2007 and is intended to identify potentially beneficial medication omissions. It was developed through evidence-based prescribing criteria and validated by expert providers. Even in the setting of polypharmacy, conditions in older adults are as likely to be undertreated as those without polypharmacy (Steinman et al., 2006). Similarly to STOPP, this list is organized by physiological system. In a study conducted in a teaching hospital, 58% of patients were found to have omissions of medications that could be providing benefit to these patients (Barry et al., 2007) (Table 2).

Table 1.

Table 2.

Identifying Polypharmacy

Referring back to the definition of polypharmacy used by the authors of this article, the use of a medication that is not indicated in a patient or is inappropriate for that individual, the best tool is a personal interview with the patient. Yang et al. (2001) conducted a study comparing medication lists obtained in a clinic versus those obtained in follow-up home patient interview and inspection. The authors concluded that in-home medication lists are more complete because 48% of the clinic medication lists had a least one omission of a regular medication. As was previously discussed, in-home visits allow clinicians to frequently monitor patients and identify when new symptoms or clinical changes have occurred. Complete information from the prescribers and patient can be used to assess the use of each medication and medication regimen as a whole, helping to identify polypharmacy. This will also be developed in depth in the second part of this article.

CGA takes a holistic approach to the patient assessment evaluating clinical, functional, cognitive, nutritional, and social parameters using multiple disciplines. This allows for a global assessment that can provide better long-term care for patients. It incorporates assessments from a multidisciplinary team including nurses, occupational and physical therapists, social workers, general practitioners, geriatricians, and pharmacists. Unfortunately, despite the use of CGA, polypharmacy continues to be a problem, which needs further attention (Sergi et al., 2011).

MAI, initially developed in 1992 by Hanlon et al., is a 10-component assessment tool to evaluate the appropriateness of medications used in older patients. The components that are included in these criteria include efficacy (as defined in clinical practice guidelines), drug dosage, interactions, cost, and duplications (Table 3).

Table 3. Medication Appropriateness Index

The ACOVE project (Wenger et al., 2001) was designed with several goals in mind, one of which was to list the medical conditions that affect this group. Appropriate use of medications is one of the 22 categories that this group identified as being a medical condition in this population. A complete list of the ACOVE quality indicators can be accessed online at: http://www.annals.org/content/135/8_Part_2/653.full.pdf+html.

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