Polypharmacy

Original Editor - Shwe Shwe U Marma Top Contributors - Shwe Shwe U Marma, Lucinda hampton and Kim Jackson

Introduction

Polypharmacy refers to the use of multiple medications in a patient, commonly an older adult. While the most commonly used definition of polypharmacy is being on five or more medicines, definitions are variable.

• The World Health Organization suggest that while the definition is numerical, emphasis should be on evidence-based practice and that the goal must be to reduce inappropriate polypharmacy.
• Each year, thousands of elderly patients suffer injury because of adverse effects from multiple medications.

Catagories

There is no universally agreed definition of polypharmacy, however it can be described in 3 groups-

1. Excessive polypharmacy (EPP): concurrent use of ten or more different drugs.
2. Polypharmacy (PP): the use of five to nine drugs.
3. No polypharmacy: taking four or less drugs (included those taking no medicines)

Prevalence

People aging more than 65 years is the group taking medications most; more than 50% of elderly patients are taking at least one medically unnecessary medication. However, polypharmacy declines in patients after 85 years of age.

Issues of Concern

Polypharmacy is a particular concern in older people due to the following reasons.

1. Adverse effects (ADE): refers to an injury resulting from the use of a drug and refers to harm caused by a drug at usual dosages. ADEs are causative in 5% to 28% of acute geriatric medical admissions. Preventable ADEs are among one of the serious consequences of inappropriate medication use in older adults. The drug classes commonly associated with preventable ADEs are cardiovascular drugs, anticoagulants, hypoglycemics, diuretics, and NSAIDs. Adverse drug effects are higher in older adults due to metabolic changes and decreased drug clearance that come with age. This risk compounds by increasing numbers of drugs used.
2. Drug interactions: The use of multiple medications increases the potential for drug-drug interactions ie the pharmacologic or clinical response to the administration of a drug combination that differs from the response expected from the known effects of each of these two agents when given alone. Cardiovascular drugs are most commonly involved in drug-drug interactions. The most common adverse events related to drug-drug interactions are neuropsychological (delirium), acute renal failure, and hypotension. eg Anti-inflammatory medications may increase blood pressure and worsen kidney function.
3. Prescribing Cascades: when additional drugs are prescribed to treat the adverse effects (ADE) of other drugs by misinterpreting the ADE as a new medical condition.
4. Inappropriate therapy, or nonadherence: especially if associated with visual or cognitive decline.
5. The risk for hip fracture: Polypharmacy has been shown as an independent risk factor for hip fractures in older adults in some case-control studies; although the number of drugs may have been an indicator of a higher likelihood of exposure to specific types of drugs like central nervous system (CNS)-active drugs associated with falls.
6. Use of Over-the-Counter and Complementary Medications: use has increased over the past decade with studies showing that these agents are highly prevalent in the elderly population. Less than half of the patients discuss the use of herbal supplements or other products or complementary medicine with their medical providers. There are safety issues regarding their use including risks for herb-drug interactions.
7. Transitions of Care: eg between hospital and home or institutional setting like a nursing home. Common source of medication errors putting patients at risk for polypharmacy. This is because many times, patients start new medications or stop previous medications, which can cause a lot of medication errors and negative outcomes.
8. Changes in Pharmacokinetics Associated with Aging: ie drug absorption, distribution, metabolism, and elimination. Physiologic changes that occur with aging result in multiple alterations to the pharmacokinetics and pharmacodynamics of drugs, which, in turn, increase the risk of adverse drug reactions. Consideration of initial dose adjustment, along with frequent medication reconciliation and analysis of the medication list, are keys to providing optimal pharmaceutical care for elderly patients.

Associated Factors

Individual/Patient Factors	Physician Factors	Systems-Level Factors
Increasing age Female gender White ethnicity/race Lower socioeconomic status Poor self-reported health Multiple chronic conditions Declining nutrition/ability to function Decreased cognitive capacity Self-medication Use of over-the-counter medications Borrowing from friends/family Use of multiple pharmacies	Lack of education/competence High patient workload Prescribing habits Adherence to multiple medical guidelines Use of potentially inappropriate medications Improper medication reconciliation Poor physician-patient communication Multiple prescribers	Different electronic medical record systems Poor physician-physician communication Lack of continuity between multiple medical providers Ineffective transitions of care

Managing Polypharmacy

• 

  List of prescribed medication should be updated and accurate
• Each clinician should review ongoing prescription
• Physician should be informed of any supplements, herbal products or over-the-counter medication a patient taking
• Understanding the purpose of each medication
• Being aware of side effects of each medication
• Simplification of medication regimen
• Discontinuation of any medication if needed
• Taking medications as prescribed
• Taking any prescribed medication should not be stopped suddenly

Conclusion

Along with all other health practitioners, physiotherapists should be aware of the tools and methods to manage polypharmacy-related issues to optimize patient outcomes.