Underuse of Medical Therapy Linked With Increased Adverse Events in Very Elderly

An analysis of community-dwelling elderly patients suggests many fail to receive appropriate medications, including ACE inhibitors, antiplatelet therapy, and statins, and that this underuse of medical therapy is associated with a significantly increased risk of poor clinical outcomes.

Overall, the underuse of appropriate medication was observed in 67% of elderly primary-care patients participating in a Belgian cohort study. Each additional medication not prescribed at baseline was associated with a 39% increased risk of death and a 26% increased risk of hospitalization at 18 months, report investigators.

Speaking with TCTMD, lead author Maarten Wauters (Ghent University, Belgium) said that in the very elderly, there’s not a lot of evidence available on medication use as these patients are frequently excluded from randomized trials. In addition, physicians might be reluctant to prescribe medication to a frailer patient, one who might be currently taking a range of drugs for various medical conditions.

“We suggest that prescribers don’t have to be alone in the position of prescribing medication,” said Wauters. “Certainly, in light of the lack of evidence in this very elderly population, we suggest using a multidisciplinary counsel to address the risks and benefits of each medication and to do regular evaluations of medications in these patients. We also suggest they evaluate the therapies from time to time, to search for those that might be misused or underused. Doctors can be helped by consulting with pharmacists or clinical pharmacologists.”

Published online this week in the British Journal of Clinical Pharmacology, the analysis included 503 participants in Belfrail-Med, a prospective, population-based cohort study of individuals 80 years of age and older. To assess misuse and inappropriate use, the researchers used the Screening Tool of Older People’s Prescriptions (STOPP-2) and Screening Tool to Alert to Right Treatment (START-2) criteria, which enabled them to cross-reference patient disease states with medication use. The individuals— mean participant age 84 years—were prescribed an average of five medications, with 58% prescribed five or more medications.

Using the START-2 and STOPP-2 criteria, drug therapy was suboptimal for a large percentage of patients. Underuse was documented in two-thirds of participants and misuse in 56%. More than one-third of elderly patients misused benzodiazepines, which are sedatives used to decrease agitation and anxiety and aid sleep, by taking the drugs for more than 4 weeks. More than 12% of participants had duplicate prescriptions of drugs in the same class, such as NSAIDs, loop diuretics, ACE inhibitors, and anticoagulants.

Regarding underuse, 26.2% of participants with systolic heart failure and/or documented coronary artery disease were not taking an ACE inhibitor and 24.3% with documented coronary, cerebral, or peripheral vascular disease were not taking antiplatelet therapy. Approximately 15% of participants aged 80 to 85 years of age with documented vascular disease were not taking a statin.   

At 18 months, 8.9% of participants had died and 31% had been hospitalized. In a multivariate analysis that included adjustment for polypharmacy and misuse, the underuse of medication was associated with increased risks of both mortality and hospitalization. For individuals with “high” underuse—those missing three or more medications—the mortality rate was threefold higher than for those taking all appropriate medications. Similarly, in these patients, the rate of hospitalization was twofold higher. There was no association between misuse of medical therapy and mortality or hospitalization in the adjusted model.

“What we knew from the past is that the misuse of medication has been linked with adverse drug events, but now our main findings are that underuse—not prescribing essential, beneficial medications—can also have an adverse on mortality and hospitalizations,” said Wauters.

The researchers are currently working on developing a computerized alert system to help prescribers identify missed or misused medications. The ideal system would include the patient information, including various disease states, and if a medication is not present, for example, the physician would receive an electronic reminder to prescribe a certain type of drug, said Wauters.

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