Medication Appropriateness in Vulnerable Older Adults

Healthy Skepticism of Appropriate Polypharmacy

Terri R. Fried, MD; Marcia C. Mecca, MD

Disclosures

J Am Geriatr Soc. 2019;67(6):1123-1127. 

In This Article

Evaluating the net Benefit of the Medication Regimen

Criteria for identifying both PIMs and PPOs focus on individual medications without considering the benefits and harms of the medication regimen as a whole. Although there are scales to measure the cumulative burden of medications with known adverse effects, such as anticholinergics and sedatives,[24,25] little evidence exists regarding the marginal benefits and harms of any given nth medication added to a regimen.[7] However, it is highly likely that the marginal effects of medications are different from their effects when considered individually. The strongest evidence for this comes from the well-established association between number of medications and likelihood of an adverse drug reaction (ADR). In a study of hospitalized persons 65 years or older, those taking eight or more medications had four times the odds of an ADR compared with those taking five or less.[26] Although number of medications is a risk factor for receipt of a PIM, it is unlikely that the large excess risk of ADRs associated with multiple medications is completely accounted for by the individual medications. Instead, this risk more likely reflects the exponentially increased number of drug-drug and drug-disease interactions that can occur when multiple medications are prescribed. In the face of an already narrowed gap between the benefits and harms of many medications for vulnerable older adults, even small excess marginal risks could tip the balance in favor of reducing the number of medications in a regimen.

A second consideration is whether the patient can/will take all prescribed drugs. Medication nonadherence is more common among individuals with cognitive impairment and more complex regimens.[27] Even if the regimen has net benefit outweighing harms and acknowledging the existence of tools to simplify complex regimens,[28] the patient may nonetheless not be able to manage the regimen. To achieve feasibility, even medications that would otherwise not be considered inappropriate will need to be discontinued. Although this principle is controversial, it achieved consensus support in a Delphi panel examining recommendations for deprescribing.[29]

Figure 1 provides a suggested approach to the evaluation of medication appropriateness that includes the key step of stratifying patients as "robust" or "vulnerable." In conclusion, all older persons require evaluation for PIMs that can be easily identified, using established tools such as the Medication Appropriateness Index, AGS Beers Criteria®, and/or STOPP. Periodic reevaluation can identify medications that no longer have indications and, if done after a change in health status, identify new risk factors for adverse events. "Robust" older persons can benefit from the identification of PPOs. For example, physicians tend to overestimate fall risks in decisions not to prescribe anticoagulants to patients for whom risk of stroke outweighs their risk of bleeding.[30] However, for vulnerable patients, clinicians should be wary of adding PPOs and have a high index of suspicion for additional PIMs. Until there are better tools to aid in their identification, clinicians must depend on the limited literature and clinical judgment. In a study of older patients admitted to an acute inpatient geriatric unit, only 34% of START criteria were implemented by a multidisciplinary geriatric team upon discharge as compared with 87% of STOPP criteria. Reasons for not following START criteria included severe disability and high risk of adverse events,[31] suggesting that seasoned clinicians can use their knowledge and experience to avoid high-risk medications in vulnerable older persons.

Figure 1.

Algorithm for evaluation of medication appropriateness in older adults. Beers, AGS Beers Criteria; MAI, Medication Appropriateness Index; PIM, potentially inappropriate medication. PPO, potential prescribing omission; START, Screening Tool to Alert to Right Treatment; STOPP, Screening Tool of Older People's Prescriptions.

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