Polypharmacy May 2008 CRIT Heidi Auerbach, MD Copyright Boston University Medical Center

Polypharmacy  Definition  Causes  Consequences  Prevention/management

Definition Suboptimal prescribing  Overuse = Polypharmacy  Inappropriate prescribing  Underuse Hanlon JT et al. JAGS. 2001;49: Fisk D et al. Arch Intern Med. 2003;163:

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):

Causes: Drug regimen changes  Any transition of care- discharges,ER  New meds, different doses…  Changes from generic to brand- nomenclature, 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, drug- food 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 dose- related 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:

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: Omori DM et al. Arch Intern Med. 1991; 151(8):

Direct Cost  Those over 65 make up 12-13% of the US population and consume roughly % 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 drug- related  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): Institute of Medicine. National Academy Press 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 ADEs- addresses specifically errors in prescribing during transitions of care Gurwitz JH et al. JAMA. 2003;289(9):

Solutions to Polypharmacy  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!