Nursing Research: Medications in Older Persons

Due to increased life expectancy, older age is associated with the prevalence of multiple comorbidities (e.g., congestive heart failure, chronic obstructive pulmonary disease, diabetes mellitus), which often necessitate life-long and multiple medication intake. Consequently, older persons are the largest consumers of medication.
Polypharmacy is worrisome in the elderly because of the increased risk for adverse events. Moreover, polypharmacy may result in nonadherence to the therapeutic regimen, a factor found to be associated with poor outcomes in view of physical and psychological health. Adherence needs to be monitored as a clinical parameter during each clinical encounter. Evaluating older person’s capabilities and risk-factors for successful management of the medication regimen should be part of a thorough geriatric assessment as a cornerstone of chronic illness management. Nurses play an important role in this assessment and assist older persons and their families in the management of and adherence to their medication regimen. Older persons are the largest per capita consumers of medications. Several international studies show that
 persons older than 65 years account for 15%–18% of the population, but consume 40%–50% of prescribed drugs (Klauber, 1996; Linjakumpu et al.,2002; Swafford, 1997). 

elderly people

Prevalence of polypharmacy increases with higher age and number of concomitant comorbidities (Linjakumpu et al., 2002; U.S. Agency for Health-care Research and Quality, 1996). In two recent large-scale studies, it was noted that11%–25% of older persons use five or more medications simultaneously (Chen,Dewey, & Avery, 2001; Linjakumpu et al., 2002). Polypharmacy is worrisome in view of the increased risk for adverse events as this maybe associated with poor outcomes in view of poor physical and psychological health. It has to be noted that, secondary to higher age or multiple chronic diseases, older persons are most vulnerable to pharmacokinetic, pharmacodynamic, and homeostatic changes (Raik, 2001). These changes make them particularly sensitive to adverse events, interactions, and toxicity of medications. Older persons are also at greater risk for inappropriate prescribing. The average clinician often lacks sufficient knowledge regarding possible drug-drug interactions. In addition, a lack of information regarding medication prescriptions ordered by other providers serves as a significant factor in increasing the complexity of the therapeutic regimen. Every new drug added to the medication regimen will increase the risk for adverse outcomes (Raik).
Suboptimal use of prescribed medications is often associated with unplanned hospitalizations among the chronically ill: 28.1% of visits in an emergency department were due to medication-related visits, and 63.35% of hospital admissions due to drug reactions could have been prevented (Mc Donnell & Jacobs, 2003). Furthermore, the risk of medication mishaps is higher in the older population due to errors in self-administration, caused in part by visual and cognitive impairment, illiteracy, high medication costs, the complexity of the medication regimen, duration of treatment, and/or side effects of the medications (Raik, 2001). Adherence is defined as the extent to which a person’s behavior (taking medications, following a recommended diet, and/or executing lifestyle changes) corresponds with the agreed recommendations of a health care provider (Haynes, McDonald, Garg, & Montague, 2003). In persons aged 60 years or older, nonadherence with medication regimens varies from 26% to 59% (Van Eijken, Tsang, Wensing, de Smet, & Grol, 2003), numbers that are very similar to those of younger populations. Nonadherence with drug treatment is highly prevalent in all chronic patient populations among different age groups and is not more prevalent in older normally aging persons, as is sometimes wrongly stated. Because nonadherence has been found to be associated with poor outcomes, adherence needs to be monitored as a relevant clinical parameter during each clinical encounter. Clinicians can use direct as well as indirect methods to assess adherence with medication regimens. Direct methods refer to assay of medication, medication by-products or tracers in bodily substances (e.g., digoxin, phenobarbital), and observation of medication administration. Indirect measurement methods are self-report, collateral report, prescription refills, pill-count, and electronic event monitoring. Yet there is no gold standard to evaluate adherence with a medication regimen, as all methods have specific drawbacks in view of underestimating of nonadherence or the lack of revealing medication-taking dynamics. Electronic event monitoring (EEM) has emerged as the most valid and reliable method to date. EEM consists of a pill bottle fitted with a cap that contains a microelectronic circuit. The date and time of each bottle opening and closing are recorded as a presumptive dose. Recorded data can be down-loaded to a computer that lists and graphically depicts individual medication-taking dynamics. Indirect, electronic event monitoring has superior sensitivity compared to other direct and indirect methods, as it allows assessment of noncompliance at a continuous level and in a multidimensional manner (De Geest, Abraham, & Dunbar-Jacob, 1996).
A number of processes associated with aging may negatively influence older persons’ ability for independent and correct medication management and prevent adherence.
Knowledge of risk-factors for nonadherence will allow identification of older patients at risk for inadequate medication management. Modifiable factors can be targeted for adherence-enhancing interventions. A selection of factors with special relevance for the older population will be discussed next. Aging is associated with decline in auditory, visual, cognitive, and functional capacities. It can be more difficult for older persons to handle childproof caps, blister packages, or nebulizers, or to swallow large pills. Adherence to medication regimens requires, among other abilities, reading labels and distinguishing tablets according to their color. Nineteen percent of persons aged 70 years and older have visual impairments, including blindness; one third have hearing impairments (Desai, Pratt, Lentzner, & Robinson,2001). Labels may be misread and colors of pills may not be recognized. Reading difficulties with regard to prescription labeling was not significantly related to non-adherence in seniors, although 38.8% were not able to read all the prescriptions labels and 67.1%did not fully understand all information (Maison, Gaudet, Gregorie, & Bouchard, 2002), admittedly restricting options for adequate medication management. Older persons have to be aware of the intended effect of the medication, how to administer it, possible side effects, and other relevant aspects of the medication regimen. A significant proportion of the older population has inadequate or marginal functional health literacy, making it difficult to process the health information and instructions given to them. Although cognitive decline is associated with aging, in the absence of pathophysiological decline such as Alzheimer disease, cognitive functioning of older persons is normally sufficient to independently manage their own medication regimen (Park et al., 1999). Forgetfulness is a common reason for nonadherence in older persons; however, severe cognitive impairment most compromises patients’ abilities to independently manage their treatment regimen. Cognitively impaired persons are more likely to receive assistance with medication management compared to cognitively intact subjects (Conn, Taylor, & Miller, 1994).

Treatment-related factors such as duration, complexity, and cost of medication regimens can also negatively affect adherence. Medication restriction, i.e., taking less medications than prescribed, is common in seniors who lack prescription coverage, particularly among certain vulnerable groups (Steinman, Sands, & Covinsky, 2001). The fact that many older persons live alone and are relatively socially isolated deprives them of necessary social support and places them at risk for depression, both of which are known risk factors for medication nonadherence (De Geest, von Renteln-Kruse, Steeman, Degraeve, & Abraham, 1998). Compliance-enhancing interventions should be built on the available empirical evidence of modifiable risk-factors and intervention studies. Evidence shows that compared with single, generalized, and short interventions, multifaceted, tailored, and continuous interventions result in improved medication adherence (Haynes, McDonald, Garg, & Montague, 2003; Peterson, Takiya, & Finley, 2003; Roter et al., 1998; Van Eijken, Tsang,Wensing, de Smet, & Grol, 2003). This implies a combination of educational, behavioral, and social support strategies tailored to the specific situation of each individual older person and his family within a biopsychological care paradigm. Moreover, it is important that older patients and their families are seen as partners in the development of tailored and multifaceted medication management interventions. Successful management of medication regimens in older persons requires an under-standing of the risks associated with polypharmacy and specific factors associated with the aging process that put patients at risk for nonadherence. Interventions aiming at sup-porting older persons and their families with regard to medication-taking further should be multifaceted and tailored along the continuum of chronic illness management.