Geriatric Pharmacology

Transcription

1 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 changes as one ages that impacts medication use Compare and contrast the Beers criteria and STOPP 1

2 Geriatric Drug Usage Patterns Ambulatory or Community 3-4meds Acute Hospital 3.5-8meds LTCF 7meds But 20% use 10+ Medicare- 41% use 5+meds Consult Pharm 2001;16:54-64 JAMA 2003;289: JGIM 2007;22:6-12 Age 65+ with Chronic Health Conditions Men Women 2

3 Chronic Diseases Medicare Beneficiaries 80% have at least 1 chronic disease 48% have at least 3 chronic diseases 21% have at least 5 chronic diseases =INCREASED DRUG USAGE Health Affairs 2003;W3:37-53 Adverse Drug Events (ADE) 27,000 ambulatory elderly 1523 ADEs/12months 27.6% preventable 42% preventable in LTCF Mostly ordering and monitoring errors JAMA 2003;289: N Engl J Med 2003;348: Am J Med 2005;118: ER Hospitalizations ( ) for ADE yo+ Nearly 100,000 ER hospitalizations 48.1% in 80yo+ 66% unintentional overdoses 4 meds/classes involved in 67% Warfarin Insulins Oral antiplatelet agents Oral hypoglycemic agents N Engl J Med 2011;365:

4 Consequences of ADE in Elderly Increased morbidity and mortality ER visits- 25% linked to ADE Hospitalizations- 49% linked to ADE Older adults are 6.8x more likely to be hospitalized from ADE than younger age JAMA 2006;296: Risk Factors for ADE- Elderly Age 85 years Low body weight or BMI< 22kg/m2 Use of 5 or more medications Use of multiple pharmacies/physicians Dementia 4+ medical problems Non-Compliance JAMA 2003;289: Pharmacokinetic changes Pharmacodynamic changes Using high risk meds Inappropriate self medication Poor education Poor/missing monitoring Hospital stay >14days Addition of 2+ meds from hospital admission Higher ADE Risks in Older Populations 8 drugs=high risk 5-7drugs=medium risk Previous ADE 4 comorbidities Liver disease Am J Med 2012;125: Renal disease High-risk drugs Cognitive impairment Living alone Nonadherence Known psychologic disorder or substance abuse 4

5 Drug Interaction Potential Schwartz JB Principles of Geriatric Medicine and Gerontology.4 th ed 1999 Falls Morbidity & Mortality Every 18 sec=er visit Risk of serious injury 4-5x higher in 85+yo 90% of hip fractures in 65+yo caused by falls Increases admissions to LTCF Medication Related Falls 1 in 3 over 65yo fall each year 6% of hospitalizations in elderly Major medications linked to falls: CNS- antidepressants, benzodiazepines, neuroleptics Anticonvulsants Select cardiovascular N Engl J Med 2003;348:

6 Costs of Potentially Inappropriate Medication(PIM) $7.2 BILLION/YEAR Med Care 2007;45: Pearls Any symptom in a geriatric person should be considered an ADE until proven otherwise Any symptom in a geriatric person should NOT be considered normal aging or worsening of current diseases without ruling out a medication related problem Pharmacokinetics & Aging PK= how the body handles a drug Absorption Distribution Metabolism Excretion 6

7 Absorption Changes- Elderly Decreased gastric emptying plus increased transit time in bowels Changes in ph Decreased active transport mechanisms Iron, Vitamin B12, Calcium Consult Pharm 2008;23: Sem Onc Nurs 2005;21:29-35 Absorption Changes Topical gels/patches- may have altered absorption from skin thinning and/or decreased blood flow to skin Decreased IM/SQ absorption if poor muscle mass and/or poor perfusion Consult Pharm 2008;23: Distribution Changes-Elderly Decreased total body water Decreased albumin (frail, malnourished) Decreased muscle mass Increased adipose tissue Consult Pharm 2008;23: Sem Onc Nurs 2005;21:29-35 Clin Geriatr Med 2002;18:

8 Metabolism Changes- Elderly Multi-pathway, complex system Some, some Cytochrome P450 isoenzymes Some, some Signficant drug interactions Consult Pharm 2008;23: Elimination Changes- Elderly Renal function decreases 1% per year over age 50 Decreased glomerular filtration rate (GFR) Lose 25-50% of GFR between 20-90yo Decreased tubular secretion Decreased renal blood flow Exp Gerontol 2003;38: Consult Pharm 2008;23: Renally Adjusted Medications MANY antimicrobials, opioids, select GI meds, select cardiovascular meds, select diabetic meds Increased accumulation of active metabolites-----toxicity 8

9 Pharmacodynamics & Aging PD= body s response to a drug Not as well understood or studied Involves altered receptors, decreased receptor affinity, altered processing of signals, altered homeostatic control P Dynamic Examples Loss of baroreceptor functionality (=falls) Increased sensitivity to central nervous system medications Increased tardive dyskinesia risk with antipsychotics Increased sensitivity to anticholinergic side effects of medications Exp Gerontol 2003;38: Anticholinergic Side Effects Confusion Memory loss Delirium Sedation Dizziness Hallucinations Cardiac conduction changes Urinary retention Constipation Xerostomia Blurred vision Unsteady gait Tachycardia Thermoregulatory impairment 9

10 Anticholinergic Burden 180/201 patients 65+yo had serum antichol activity with cognitive impairment Can exacerbate underlying dementia and/or antagonize effects of dementia meds AC Risk Scale, AC Drug Scale, AC Burden Scale Arch Gen Psychiatry 2003;60: , Arch Intern Med 2008;168: , J Clin Pharmacol 2006;46: , Aging Health 2008;4: Meds w/anticholinergic Activity Antispasmodics- dicyclomine, oxybutynin Antihistamines- diphenhydramine Antidepressants- tricyclics, paroxetine, trazodone, duloxetine Antipsychotics- olanzapine, risperidone Antiemetics- prochlorperazine, promethazine Muscle relaxants- cyclobenzaprine Urinary incontinence meds- oxybutynin Beers List or Beers Criteria List of potentially inappropriate meds (PIM) to use in geriatric patients LTCF residents elderly older adults older adults J Am Geriatr Soc 2012;60:

11 Outcomes with Beers List Meds Studies show 14-40% inappropriate prescribing Increased hospitalizations Increased ER visits Increased healthcare costs Death Ann Pharmacother 2007;41: J Am Geriatr Soc 2011;59: Ann Pharmacother 2011;45: Arch Intern Med 2011;171: Beers Categories I. PIM/classes to avoid Diphenhydramine, sliding-scale insulin, benzodiazepines, digoxin>125mcg, antipsychotics (in behaviors with dementia) II. PIM/classes to avoid with certain diseases/syndromes Tramadol/Seizure history, NSAID/Heart failure, Anticholinergics/Dementia PIM= Potentially Inappropriate Medication Beers Categories III. Meds to be used with caution Aspirin for cardiac primary prevention in 80yo+ ***Hospice/palliative care acknowledgement for patient-specific circumstances (specific, short-term use) 11

12 STOPP- Screening Tool of Older Person s Prescriptions UK alternative to Beers List 65 criteria for potentially inappropriate prescribing Incorporates concurrent diagnoses Ibuprofen in hypertension or heart failure Furosemide as 1 st monotherapy for BP Int J Clin Pharmacol Ther 2008;46:72-83 STOPP versus Beers 600 consecutive 65+ yo over 4 months 158 (26.3%) patients had 329 ADEs 219 (66.6%) of ADEs related to admission 151 (68.9%) of admission ADEs were avoidable/potentially avoidable Likelihood of serious, avoidable ADE STOPP----OR 1.847, p<0.001 Beers----OR 1.276, p=0.11 Arch Intern Med 2011;171: Good Palliative-Geriatric Practice Algorithm 70 patients (mean 82.8yo), 19 months 61%--3 comorbids, 26%--5 comorbids 311 meds (58% of meds) discontinued in 64 patients Successful discontinuation in 81% No significant adverse effects 88% reported global improvements Arch Intern Med 2010;170:

13 10 Step Framework- Med Reduction in Older Patients 1. Ascertain all drugs 2. Identify patients at high risk of or experiencing ADEs 3. Estimate life expectancy 4. Define care goals in reference to life expectancy, level of functional incapacity, quality of life, and patient/ caregiver priorities Am J Med 2012;125: Step Continued 5. Define and confirm existent indications for ongoing treatment with reference to defined care goals 6. Determine time until benefit for preventative disease-specific medications 7. Determine disease-specific benefit-harm thresholds that may support treatment discontinuation 10 Step Continued 8. Review the relative utility of individual drugs 9. Identify drugs that may be discontinued or have their dosing modified 10. Implement and monitor revised therapeutic plan with ongoing reappraisal of drug utility and patient adherence 13

14 Geriatric Med Considerations Older adults *** ***Points of change Inc. Use of Medications *** Inc. Negative Outcomes Pearls of Geriatric Pharmacology M A S T E R minimize number of meds alternatives to be considered start low and go slow titrate therapy educate patient review and monitor regularly Consult Pharm 2008;23: Questions & Answers Thank you for your attendance! 14