1. 
   

   What really defines polypharmacy?

   
   
2. 
   

   What are the consequences of polypharmacy?

   
   
3. 
   

   Who is at risk for polypharmacy?

   
   
4. 
   

   How can clinicians reduce polypharmacy?

Polypharmacy is most often defined in one of two ways: the use of multiple medications categorized by medication count or the use of unnecessary medications. Medication counts ranging from two to nine medications have been used to classify a patient as having polypharmacy. Lacking consensus about the specific medication count threshold, studies describing the occurrence of polypharmacy have chosen various numbers to operationalize their definition. As most elderly patients have multiple comorbidities requiring multiple medications based on established medical guidelines, this controversial definition fails to consider medication appropriateness. In fact, polypharmacy, measured by medication count only, may be appropriate to treat a patient with a number of medical conditions. The second definition of polypharmacy requires a review of medication appropriateness. Drugs deemed unnecessary include those that lack an indication or efficacy for a condition or therapeutically duplicate another medication, such as a prescription of a proton pump inhibitor for a patient with no history of peptic ulcer disease or a need for stress-ulcer prophylaxis. Few studies have evaluated this definition of polypharmacy despite its clinical relevance.

An in-home survey of 3005 participants of whom 58% ≥ 65 years of age reported that overall 94% of older adults took one or more medications and the average number of prescription medications was 3.6 per person. Over a third of men and women aged 75 to 84 years took ≥ 5 prescription (Rx) drugs. Moreover, nearly half of men and women ≥ 65 years of age reported the use of over-the-counter (OTC) drugs.

Table 171-1 lists the most common prescription and OTC drugs reported by gender. It is also important to note that 54% of older men and women reported use of dietary supplements.

Table 171-2 lists the most common dietary supplements reported by gender.

Hospitalized older adults have even higher medication use. Surprisingly, no national US data provide information about the epidemiology of drug use in hospitalized elders. One study of 834 older frail inpatients from 11 VA hospitals found that the average number of prescription drugs was 7.6 whereas the number of nonprescription drugs used was 2.6. This contrasts with a study from Ireland where the average number of medications was 5 per elderly hospitalized patient.

Table 171-3 lists the most common medications taken by older adults in a single US hospital. As a reflection of indications of hospitalization, hospitalized compared to community dwelling elders more commonly take opioid analgesics and antibiotics.