Aging and Geriatric Assessment March 31, 2008 Sharon Leigh, Pharm D. BCPS Providence ElderPlace

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1 Aging and Geriatric Assessment Page 1 Aging and Geriatric Assessment March 31, 2008 Sharon Leigh, Pharm D. BCPS Providence ElderPlace I. Aging A. Demographics Age 65+ population 3.1 million million million million 2003 (12% of total population) 44.1 million 2008 (15% of total population 71.5 million 2030 (20% of total population) Age 85+ population 4.2 millions 2000 (1.7%) 7.4 millions 2030 (2.1%) 2006 Medicare enrollee years: 17.3 million (43%) years: 12.7 million (31%) >85 years: 3.8 millions (10%) Average life expectancy 2002 is 77.3 years Women 79.9 years Men 74.5 years Women 65+ = 20.8 million, Men 65+ = 14.8 million Frail elderly 80% of elderly have at least one chronic condition 50% have at least 2 chronic conditions that lead to disability 38.7% of 65+ population believe they are in good health 44% of 75+ population have limitation in daily activity 1.9 million resides in nursing homes (>85 years: 45%, years: 34%, years: 12%, <65 years: 9%) B. Age related changes (physiologic changes) Less lean body mass, increase in body fat Loss of skeletal bone mass Atrophy of the thyroid gland Decreased cell mediated immunity Reduction in cardiac output with activity Decrease in lung tissue elasticity and strength of respiratory muscles Decrease in renal blood flow and GFR (glomerular filtration rate) Decrease in GI motility and acid production Hepatic blood flow and liver mass are reduced

2 Aging and Geriatric Assessment Page 2 Changes in sensory organs: vision (decrease night vision and visual acuity), hearing (less tone sensitivity), taste (decrease in sweet, sour and bitter taste but not in saltiness), decrease thirst response C. Pharmacokinetic changes Absorption gastric acidity, blood flow to small bowel delayed gastric emptying Rate of absorption of enteric coated tablets and sustained release products could be altered but the extent of the absorption is not changed. Net effect: overall bioavailability of most drugs are not altered Distribution total body water, lean body mass, plasma albumin adipose tissue, alpha-1 glycoprotein Net effect: 1. Increase in serum concentration of water soluble drugs due to decreased Vd (ie: theophylline, lithium, aminoglycosides, alcohol) 2. Increase in serum concentration of drugs that distribute to lean body mass (ie: digoxin) 3. Decrease protein binding of drugs leading to increase in free drug (ie: phenytoin, warfarin) 4. Delay in clearance of lipophillic drugs and prolonged drug effect due to increased Vd (ie: benzodiazepines) Increased volume of distribution Diazepam Chordiazepoxide Salicylates Tolbutamide Thiopental Decreased volume of distribution Digoxin Theophylline Alcohol Lithium Meperidine Metabolism first pass metabolism due to reduction in liver mass and reduction in hepatic blood flow Minor decrease or no change in phase I metabolism (oxidation, reduction, hydrolysis) primarily by CYP P450 isoenzyme systems Unchanged phase II metabolism (glucoronidation, sulfation) Net effect: 1. Increased bioavailability of drugs with extensive first pass metabolism (ie: morphine, metoprolol, labetolol, statins, verapamil, nitrates) 2. Increased half life of drugs that undergo phase I metabolism (ie: diazepam)

3 Aging and Geriatric Assessment Page 3 Drugs with prolong hepatic metabolism Amitriptyline Meperidine Barbituates Propranolol Chlordiazepoxide Quinidine Diazepam Warfarin Flurazepam Phenytoin Labetolol Lidocaine Elimination in renal blood flow and glomerular filtration rate (renal function decreased by 1% per year after age 40) Serum creatinine is not a reliable indicator of renal function in the elderly. Creatinine clearance must be calculated. Most widely use formula for Clcr (creatinine clearance) is: Clcr (ml/min) = (140-age) x weight (kg) 72 x serum Cr (mg/dl) For female: multiple by 0.85 For sever muscle wasting or bedridden patient: Sanaka formula may be more accurate: Men = (19 x Albumin + 32) x weight (kg) 100 x Scr Women = (13 x Albumin +29) x weight (kg) 100 x Scr Net effect: increased half life of drugs with predominant renal elimination Drugs with decreased renal clearance Amantadine Hydrochlorothiazine Ceftriaxone Lithium Cimetidine Ranitidine Digoxin Sotalol Vancomycin Gentamicin Ciprofloxacin Trimethoprim/Sulfamethoxazole D. Pharmacodynamic changes Not well studied Certain receptors have shown to be less sensitive Beta receptors Baroreceptors Insulin receptors

4 Aging and Geriatric Assessment Page 4 Elderly tend to be more sensitive to the centrally acting agents Neuroleptics Antidepressants Analgesics Benzodiazepines II. Drugs and aging A. Medication use 3 billion prescriptions ($182 billion) are filled by elderly in 2002 Average number of Rx filled by 65+ population was 24.3 (female 27.3, male 20.3) in 2003 From 1998 to 2003 patients using >5 meds increased from 54% to 67%, >10 meds increased from 19% to 28% Elderly accounts for 35% of all prescription medications and 60% of all OTC 40% of the elderly use 5 different drugs per week (Kaufman DW. et al. JAMA 2002;287: ) 12% of the elderly use 10 different drugs per week (Kaufman DW. et al. JAMA 2002;287: ) B. Reasons for multiple drug use Prevalence of more chronic diseases Multiple age related diseases Availability of medications with direct advertising Preventative care Inappropriate use of medication 1987: 23.3% of elderly in the community used at least 1 of 20 inappropriate medications (NMES National Medical Expenditure Survey) 1995: 17.5% of elderly in the community used at least 1 of 20 inappropriate medications (MCBS Medicare Current Beneficiary Survey) 1996: 21.3% of elderly in the community used at least 1 of 33 inappropriate medications (NMES) C. Implications of polypharmacy Drug-drug interactions Risk for adverse event Most likely to be on medication that is inappropriate or ineffective High risk medications o Drugs that prolong QTc interval o Drugs with narrow therapeutic index (warfarin, digoxin) o Drugs with anticholinergic effects o Sedative drugs o Diabetes drugs D. Medication coverage by Medicare Part D Prescription medication coverage started January 2006 Expected to cost $400 billion over next 10 years

5 Aging and Geriatric Assessment Page 5 MTMS (medication therapy management services) for elderly who have multiple chronic diseases (>2 of the following: diabetes, asthma, heart failure, hypertension), on multiple meds (>5), and annual cost of $4000 Coverage is as follow: $250 deductible Annual spending of $251-$2250: Medicare will pay 75% Annual spending of $2251-$5100: Medicare will pay 0% Annual spending of >$5100: Medicare will pay 95% E. Medication related problems in the elderly Prescribing characteristics Patient characteristics Cormorbid conditions Wrong or unnecessary Age 85 or older Decreased kidney drug Living alone function High dose More than 9 meds/day Low vision and hearing Long duration of therapy More than 12 Dementia Narrow therapeutic index doses/day Low body weight or BMI Lack of monitoring More than 6 chronic Functional impairment conditions F. Adverse drug reactions (ADR) Elderly are 2-3 times more likely to experience ADR Risk of hospitalization due to an ADR is 5-6% in younger population, but 17% in age 65+ population Elderly who takes 1-3 medications have 6% incidence of ADR, 7 or more medications have 51% incidence of ADR Nearly 50% of all emergency room visits for ADR are due to 3 drug classes: oral anticoagulants or antiplatelet agents, antidiabetic agents, narrow therapeutic index agents 1998 Alliance for Aging Research Report list medication-related problems as the fifth most costly disease affecting the elderly Adverse events may have resulted from +/-medication errors (errors in prescribing, dispensing, patient adherence, and monitoring) For ambulatory elderly population: 9.6% life-threatening or fatal, 28.3% serious events, 62% significant (Gurwitz JH. et al. JAMA 2003;289: ) 1. Cardiovascular, antibiotics, diuretics, non-opioid analgesics, anticoagulants, hypoglycemics, steroids, opioids, antidepressants, antiseizure % of all ADE were considered preventable (18.3% life-threatening or fatal, 39.7% serious, 42% significant) 3. Of the preventable ADE 58.4% errors were identified in prescribing stage, 60.8% in the monitoring stage of pharmaceutical care, 21.1% in patient adherence 4. Preventable prescribing stage errors include: wrong drug/wrong therapeutic choice, wrong dose, inadequate patient education, drug interaction. Preventable monitoring stage errors include: inadequate lab monitoring of drug therapies, delayed response or

6 Aging and Geriatric Assessment Page 6 failure to respond to signs and symptoms of drug toxicity or lab evidence of drug toxicity. III. IV. Geriatric Syndromes A. Cardiac diseases: CHF, atrial fibrillation, coronary artery disease, angina B. Endocrine diseases: hypothyroidism, diabetes, osteoporosis, hyperlipidemia C. Neurological diseases: Parkinson s, Alzheimer s dementia, delirium, depression D. Functional impairments: falls, gait instability, vision, hearing, urinary incontinence E. End-of life care Challenges in geriatric care Elderly patients are not represented in Phase III or clinical trials Limited number of health professional trained in the field Finding an appropriate level of care for the elderly in the community Coordination of care for chronic diseases V. Geriatric Assessment Must be multidisciplinary or interdisciplinary Area of focus should include evaluation of physical and mental health, social and economic status, functional status, environmental characteristics Medication history Rx, OTC, herbals best to ask patient to bring in actual bottles Social drug use alcohol, tobacco, caffeine, others Immunization ask about annual flu, pneumococcal, tetanus booster Allergies and adverse reactions ask about specific reactions to medications Medication compliance/adherence 40% of elderly patients do not take their medications as prescribed Reasons for noncompliance include: not knowing the indication, confusion about dosage schedule, unwanted or side effect, cost of medication Medications to avoid in the elderly (Beers, M. Arch Intern Med 1997;157: , 2003;163: ) Agents Reasons to avoid in the elderly Propoxyphene Minimal analgesic effect and has active metabolite with CNS side effects Indomethacin In addition to NSAIDs adverse effects (renal and GI), it has CNS side effects Trimethobenzamide Least effective anti-emetic with EPS side effects Methocarbamol, Carisoprodol, Cyclobenzaprine Muscle relaxants are poorly tolerated by the elderly leading to anticholinergic side effects, sedation and weakness

7 Aging and Geriatric Assessment Page 7 Agents Flurazepam, Diazepam, Chlordiazepoxide Amitriptyline, Doxepin Disopyramide Chlorpropamide Methyldopa, Reserpine Diphenhydramine, Chlorpheniramine, other antihistamine combinations Meperidine NSAIDS Naproxen, Piroxicam, Oxaprozin Nitrofurantoin Cimetidine Others: Barbiturates, Pentazocine, Phenylbutazone, Meprobamate, Belladonna Reasons to avoid in the elderly Benzodiazepines have long half-life in the elderly producing prolonged sedation and increase in falls and fractures Strong anticholinergic and sedating properties Of all antiarrhythmic drugs, it is the most potent negative inotrope and therefore may induce heart failure in the elderly. It also has a strong anticholinergic property. Prolonged half life in the elderly can cause prolonged and serious hypoglycemia. It can also cause SIADH. Can cause bradycardia and exacerbate depression Has potent anticholinergic activity Active metabolite with long half life and CNS side effects Long term use at full dosage can result in GI bleed and renal impairment Potential of renal impairment and pulmonary toxicity Potential for many drug interactions and CNS adverse effects Medications that are underused in the elderly Conditions Coronary artery disease, angina, peripheral artery disease, stroke prevention Status post MI Hypertension CHF, diabetic with hypertension Coronary artery disease, hypercholesterolemia Chronic atrial fibrillation Recurrent major depression Medications Baby Aspirin Beta blockers Thiazide diuretics Beta blockers ACE inhibitors Angiotensin II receptor blockers Statins Warfarin with INR goal of 2-3 Antidepressants Important medication classes that need monitoring Anticholinergics

8 Aging and Geriatric Assessment Page 8 Alpha blockers Beta blockers and beta agonists ACE inhibitors and ARB CNS drugs (antidepressants, antipsychotics, antihistamines, anticonvulsants, benzodiazepines) Opioids NSAIDs Anticoagulants Medication counseling and education Give simple and relevant information Adjust pace and allow adequate time for patient to respond Consider alternative approach based on special need (hearing or visually impaired) Augment verbal communication with other methods (writing, signs, gestures) Evaluate understanding frequently and rephrase if necessary Prepare to spend more time to answer questions 10 steps in appropriate prescribing for the elderly Use a drug with established efficacy in the elderly (evidence based prescribing with risk/benefit assessment) Start with low dose and titrate slowly Screen for drug-drug, drug-disease interactions Know the characteristic of the drug (ie: lipophillic) and the patient (ie: renal function) Avoid treating side effect of one drug with an another drug Keep dosing regimen simple (qd or bid dosing) Encourage treatment compliance Discontinue drugs that are no longer indicated or had significant side effects. The drug is affordable to the patient Frequent follow up and monitoring after staring a new drug VI. End of life care/ Palliative care Power of attorney for health care POLST (Physicians Order for Life Sustaining Treatment) Managing symptoms other than pain Shortness of breath or dyspnea: oxygen, opioids (morphine), benzodiazepines (lorazepam), furosemide Secretions: hyoscyamine sublingual tablets, atropine drops, scopolamine patch Nausea: prochlorperazine, promethazine, 5HT3 antagonist (ondansteron), antidopamine agents (haloperidol), steroids Terminal agitation or agitated delirium: benzodiazepines (lorazepam), antidopamine agents (haloperidol)

Geriatric Pharmacology

Geriatric Pharmacology Janice Scheufler R.Ph.,PharmD, FASCP Clinical Pharmacist Hospice of the Western Reserve Objectives List three risk factors for adverse drug events in the elderly Discuss two physiological