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Polypharmacy of Older Adults. Objectives. Describe the demographics of medication usage Identify the effects of physiologic changes on drug absorption, distribution, and clearance Describe adverse reactions to medications
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Objectives • Describe the demographics of medication usage • Identify the effects of physiologic changes on drug absorption, distribution, and clearance • Describe adverse reactions to medications • Identify iatrogenic problems associated with multigeriatric syndromes and their medication regimens.
Objectives • Discuss strategies for preventing polypharmacy and enhancing medication compliance / adherence. • Appreciate complex cost issues related to medications • Discuss effects of tricyclic antidepressant drugs on older adults
Polypharmacy “many drugs”…indicates the use of more medication than is clinically indicated or warranted. 5+ drugs 2000 = 200 million visits to the doctor • No prescription (30%) • Prescription of 1 - 2 drugs (30%) • Prescription of 3+ drugs (30%)
The Typical Older Adult….. • Takes 4 to 5 prescription and 2 OTC drugs at a time; fills 12 – 17 prescriptions/year • Is on fixed income, whose main source of income is Social Security • Spends an average of $955 for medications • In ambulatory: 2 – 4 prescription drugs • In long term care: 2 – 20 prescription drugs
Physician Factors • Presuming patient expects prescription medication and no medication review • Prescribing without sufficient investigation of clinical situation • Unclear, complex, incomplete instruction; not simplifying the regimen • Ordering automatic refills • Lack of knowledge of geriatric clinical pharmacology……inappropriate prescribing
Patient Factors • Seeing multiple physicians and pharmacies • Hoarding of medications • Inaccurate reporting of ALL medicines concurrently being taken • Assuming that when medication starts, they can continue indefinitely • Changes in daily habits • Changes in cognition, depression, insufficient funds, declining function, living alone
Polypharmacy leads to… • Adverse drug reactions • Drug-drug interactions • Decreased medication compliance • Poor quality of life • Unnecessary drug expense
Effects of Physiologic Aging • Absorption • Delayed gastric emptying; decreased gastric acidity; decreased splanchic blood flow • Drug Distribution • Higher percentage of fat; decreased total body water; decreased plasma albumin concentration
Effects of Physiologic Aging • Serum Concentration • Change in body composition changes serum concentration of water-soluble drugs • Change in fat mass affect concentration of fat-soluble medications • Drug Clearance • Altered liver metabolism; decreased renal excretion of drugs
Adverse Drug Reactions • Simulate conventional image of ‘growing old’: unsteadiness, confusion, nervousness, fatigue, insomnia, drowsiness, falls, depression, incontinence, malaise • Criteria for potentially inappropriate medication use in older adults (US Consensus Panel of Experts, 2003)
Adverse Drug Reactions • Fifth leading cause of death in older adults • Falls from orthostatic hypotension • Confusion and disorientation • Hepatic toxicity • Renal toxicity • *Creatinine clearance formula
Iatrogenic Problems • Anticholinergics: confusion; orthostatic hypotension; dry mouth; blurred vision; urinary retention • Tricyclics: confusion and unstable gait • Antiemetics: confusion; orthostatic hypotension; blurred vision; falls; dry mouth; urinary retention
Iatrogenic Problems • Digoxin: toxicity • H2 Blockers: confusion • Benzodiazepines: CNS toxicity • Narcotics: constipation; “start low; go slow”
Preventing polypharmacy • Requires social and nursing support • Enhancing compliance: • Patient education – written instruction • Sensitivity to lack of money to buy medications • Counseling • Need to take medication even if ‘feeling good’
Enhancing compliance • Improve provider-patient communication: more time with physician and pharmacist • No pill sharing • Assess other remedies patient uses • Support Systems: Medication Event Monitoring systems (MEMS) • At least yearly, ask patient to bring ALL medications for review
Cost of Medications • 65% of noninstitutionalized Medicare beneficiaries – have some form of prescription drug coverage • Spend less ($310/year) than those without drug coverage ($590/year) • 60% employer-sponsored or private policy • 20% Medicare + Choice HMO • 20% supplemental Medicaid, other public programs
Cost of Medications Medicare Prescription Drug, Improvement and Modernization Act of 2003 (comprehensive plan will be effective 1/2006) The Discount Card Program • NOT a comprehensive benefit • Voluntary and temporary • Immediate assistance in lowering drug costs for 2004 and 2005
Cost of Medications The Discount Card Program • Medicare will contact private companies: 10% – 25% savings • Choose a prescription drug plan; pay a premium $35.00 • Pay $250.00 deductible; Medicare will pay 75% of cost from $250 to $2,250 • Recipient will pay 100% from $2,250 - $3,600 • Medicare will pay 95% after recipient spends $3,600
Cost of Medications • Older adults save money on prescription drugs by • Cutting medications in half • Borrowing money from friends • Discontinuing certain medications because they ‘feel good’
Tricyclic antidepressants • Cause adverse anticholinergic effects • Caution when using in older adults with glaucoma and cardiac arrhythmias • Hypotension, tachycardia, and arrhythmia • Sedation, fatigue, anxiety, impaired cognitive function, seizures, extrapyramidal symptoms
Summary • Demographics of medication usage • Physiologic changes of aging and effects on drug absorption, distribution and clearance • Adverse drug reactions • Iatrogenic problems • Preventing polypharmacy / enhancing compliance • Cost Issues • Effects of tricyclic antidepressants