Download Polypharmacy

Polypharmacy
May 2008 CRIT
Heidi Auerbach, MD
Copyright Boston University Medical Center
Polypharmacy
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Definition
Causes
Consequences
Prevention/management
Definition
Suboptimal prescribing
 Overuse = Polypharmacy
 Inappropriate prescribing
 Underuse
Hanlon JT et al. JAGS. 2001;49: 200-9.
Fisk D et al. Arch Intern Med. 2003;163: 2716-2724.
Causes: Age and Chronic Dz
 Increased prevalence of somatic complaints
and chronic disease
 Community elders- 90% > 1med; 40% >
5meds; 12% > 10meds.
 Highest number of drugs per person in
greater than 80 yr olds
Gurwitz JH et al. JAMA. 2003;289(9): 1107-1116.
Causes: Drug regimen
changes
 Any transition of care- discharges,ER
 New meds, different doses…
 Changes from generic to brandnomenclature, color and/or shape
Causes: Providers/Patients
 The more the providers and visits, the more
the # meds pt takes
 2/3 of all physician visits end with a
prescription
 Expectations to receive medication
 Not communicating with PCP about med
changes
 Self-treatment
Complications of
Polypharmacy
 Increased incidence of side effects and
adverse drug reactions (ADRs)
 Noncompliance or nonadherence
 Increased cost
Side Effects and ADRs
 Side effects: considered minor enough to
allow continuation of therapy
 Adverse Drug Reactions (ADRs): May
necessitate discontinuation of drug and
require treatment of adverse event
 Due to : drug-drug interactions, drug-dz
interactions, drug-herbal interactions, drugfood interactions, rxn to pharmacokinetics or
dynamics, idiosyncratic
ADRs
 Elderly 7 times more likely to have
unwanted side effect and 2-3 times
more likely to have ADRs
 Multiple meds is the factor most strongly
correlated with increased risk of ADRs
 Exponential increase in ADRs with
addition of more drugs to a regimen (2
drugs-15%, 5 drugs-50-60% )
Pharmacokinetics and
Pharmacodynamics
 May predispose to side effects and
ADRs
 Age-related changes- renal and hepatic
 Tend to produce increased risk of doserelated adverse drug reactions which
may be avoided by dose reduction and
careful titration and monitoring of drug
levels (e.g. warfarin, digoxin)
Noncompliance/Nonadherence
Definition
 Not taking meds as prescribed
 Correlates more strongly with number of
meds, rather than age.
 The greater the number of meds, the greater
the nonadherence.
 Adherence inversely proportional to
frequency of dosing
Osterberg L, Blaschke T. NEJM. 2005; 353: 487-97.
Factors leading to
nonadherence
Intentional and unintentional factors:
 Cognitive impairment/psych issues
 Lack of insight into illness
 Illiteracy, language/cultural issues
 Misunderstanding verbal instructions
 Lack of follow up
 Cost and other social barriers
 Complexity of med regimen
 Side effects/ADRs
Statistics on Nonadherence
 Elderly: 26-59% with nonadherence
 33-69% of drug-related admissions
result from nonadherence (for all pts)
 Patients discharged with 4 or more
meds- over 50% error rate
Osterberg NJ, Blaschke T. NEJM. 2005; 353: 487-97.
Omori DM et al. Arch Intern Med. 1991; 151(8): 1562-4.
Direct Cost
 Those over 65 make up 12-13% of the
US population and consume roughly 3540% of prescription drugs
 Drug prices continue to rise– drug costs
often drive pt choices of health plan and
discretionary noncompliance
Indirect Cost
 10-30% elderly hospital admissions are drugrelated
 ADEs in 20% of patients on transfers
 Estimated 7000 deaths per yr from ADEs
 Mean length of stay, cost and mortality double
for pts with ADEs.
Bookvar K et al. Arch Intern Med. 2004; 164(5): 545-50.
Institute of Medicine. National Academy Press. 2000.
Classen DC et al. JAMA. 1997;227:301-6.
Medication Reconciliation
 ADEs- Injury resulting from using a
particular drug due to error or from
ADRs.
 Multiple categories of error
 Prescribing, dispensing, administering,
patient adherence, and monitoring
 JCAHO standard to reduce ADEsaddresses specifically errors in
prescribing during transitions of care
Gurwitz JH et al. JAMA. 2003;289(9):1107-1116.
Solutions to Polypharmacy
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Review medication
Anticipate ADEs
Avoid errors- prescribe carefully
Give verbal and written instructions
Simplify
Understand obstacles (cost, memory loss…)
Enlist family/nursing/PCP
Make sure there is good follow up
Always Remember
 “Prescribing cascade”- a drug added to
treat (mistakenly) the ADR of another
drug
 Clinical Pearl- “Any symptom in an
elderly person should be evaluated as a
potential ADR until proven otherwise”
 Many geriatric syndromes can occur as
a consequence of medications: delirium,
falls and fractures, incontinence
Take Home Message
 Polypharmacy is a reality of prescribing
when patients have multiple
comorbidities.
 We must all anticipate and guard
against the potential complications of
polypharmacy.
 Optimal prescribing is key!