POLYPHARMACY 

 Polypharmacy is defined simply as the use of multiple medications by a patient. The precise minimum number of medications used to define “polypharmacy” is variable, but generally ranges from 5 to 10 . While polypharmacy most commonly refers to prescribed medications, it is important to also consider the number of over-the-counter and herbal/supplements used.

The issue of polypharmacy is of particular concern in older people who, compared to younger individuals, tend to have more disease conditions for which therapies are prescribed. It has been estimated that 20 percent of Medicare beneficiaries have five or more chronic conditions and 50 percent receive five or more medications .

The use of greater numbers of drug therapies has been independently associated with an increased risk for an adverse drug event, irrespective of age. There are multiple reasons why older adults are especially impacted by polypharmacy:

• Older individuals are at greater risk for adverse drug events due to metabolic changes and decreased drug clearance associated with aging; this risk is compounded by increasing numbers of drugs used.
• Polypharmacy increases the potential for drug-drug interactions.
• Polypharmacy was an independent risk factor for hip fractures in older adults in one case-control study, although the number of drugs may have been an indicator of higher likelihood of exposure to specific types of drugs associated with falls (eg, CNS active drugs) .
• Polypharmacy increases the possibility of “prescribing cascades” ... A prescribing cascade develops when an adverse drug event is misinterpreted as a new medical condition and additional drug therapy is then prescribed to treat this medical condition.
• Use of multiple medications can lead to problems with medication adherence, compounded by visual or cognitive compromise in many older adults.

A balance is required between over- and underprescribing. Multiple medications are often required to manage clinically complex older adults. Clinicians are often challenged with the need to match the complex needs of their older patients with those of disease-specific clinical practice guidelines. For a hypothetical older female patient with chronic obstructive pulmonary disease, type 2 diabetes, osteoporosis, hypertension and osteoarthritis, clinical practice guidelines would recommend prescribing 12 medications for this individual .

It is particularly important to reconsider medication appropriateness late in life. The process considers the patients’ remaining life expectancy and the goals of care in reviewing the need for existing medications and in making new prescribing decisions. For example, if a patient’s life expectancy is short and the goals of care are palliative then prescribing a prophylactic medication requiring several years to realize a benefit may not be considered appropriate. This is increasingly being recognized as an important consideration when managing individuals with advanced dementia . Additionally, therapeutic medications (eg, antibiotics for pneumonia) may not increase comfort or quality of life when palliative care is the objective