1. Problems of Polypharmacy
Dr Nivi Singh
Elderly Care Department

2. Definition
Multiple drug use by patients
4 or more medications

3. Elderly Medication use increases with age
Over 60s - 19% of the population
57% of dispensed prescriptions
Over 70s - 20% taking > 5 medications

4. Causes
Appropriate
Inappropriate

5. Appropriate Multiple medical problems
New drugs for previously untreatable dx
Proof of efficacy of treatment in elderly

6. Usually/always Inappropriate
Multiple drug prescribers
Direct relationship btn the number of prescribing physicians and the incidence of ADRs
Non-medical prescribing
No regular medication review
Prescribing cascade
Prescribing of drugs that are not indicated

7. Patient factors Inaccurate drug history Underreporting of symptoms
Hoarding medications
Reluctance to discontinue medication

8. Associations Adverse drug reactions
Reduced compliance - > 2daily doses or >3 different drugs
Poor quality of life
High rate of symtomatology
Hospital admission
Longer length of stay

9. Associations
Increased mortality
Readmission on discharge
Drug expense

10. Adverse Drug Reaction A response to a drug that is:
noxious and unintended
occurs in doses normally used for the
treatment, prophylaxis, or diagnosis of
disease, or the modification of
physiological function (WHO)

11. ADRs Increase morbidity and mortality Underestimated
Implicated in ~17% hospital admissions
~30% of elderly pts exposed to drugs that may interact with one another

12. Number of drugs being taken
ADRs
The most consistent risk factor for an ADR is:
Number of drugs being taken
ADR rate 1.2% with 1 drug
10% with 9 drugs
50% with 10 drugs

14. Mechanisms of altered drug response in the elderly

15. Changes with age Altered drug pharmacokinetics
changes in absorption, distribution, metabolism and excretion
Altered drug pharmacodynamics
altered tissue sensitivity

16. Volume of Distribution
Increased % of body fat
Reduced lean body mass
Reduced total body water (15%)

17. Changes in protein binding
Decrease in plasma proteins
reduced protein bound (inactive) drug
greater amount of free (active) drug
increased drug effect, potentially resulting in toxicity

18. Metabolism Reduction in hepatic blood-flow and mass
Hepatic clearance of many drugs is reduced
Care - drugs with a narrow therapeutic range that are metabolised by the liver (eg. warfarin, phenytoin, theophylline)

19. Excretion Fall in GFR and creatinine clearance
Reduces elimination of many drugs
Care - narrow therapeutic range drugs eliminated partially or totally by the kidney (eg. digoxin, lithium and aminoglycoside antibiotics)

20. Pharmacodynamics
Changes occur in end-organ responsiveness to medications
Due to alterations in receptors and homeostatic mechanisms
e.g. an increased receptor response is seen for benzodiazepines, opiates, and warfarin
Increased likelihood of an ADR

21. Drugs that commonly produce adverse effects in elderly

22. Categories of medication
Medication Category
Cardiovascular
% enrollees 53
Antibiotics 45
Diuretics 30
Opioids 22
Non-opioid analgesics 20
Antidepressants 13
Sedatives and hypnotics
Anticoagulants 7

23. Recognising ADRs Constipation Confusion Dizziness Depression
Incontinence
Nausea
Unsteadiness

24. Falls Increased risk of falls
Polypharmacy is a marker of underlying comorbidity
High risk medications

25. Benefits of reducing polypharmacy
Reduced ADRs
Improved compliance
Improved patient quality of life
Reduced hospital admissions
Lower risk of drug interactions
Fewer drug errors
Reduced prescribing costs

26. NSF
Gain the max benefit from their medication to increase their quality and duration of life
Avoid excessive, inappropriate, or inadequate consumption of medicines

27. Solutions

28. Basic principles of good prescribing
Accurate diagnosis
Non-pharmacological agent
Start with lowest dose – Start low; Go slow
Consider potential side-effects and their impact
Review entire medication regimen

29. Regular medication review
>4 medications 6-monthly review
< 4 medications annual review
Full drug history
Over-the-counter medication
Alternative drug therapies

30. Alternative drug therapies
Gingko, garlic and ginseng – all interact with warfarin and possibly aspirin
Alcohol - exacerbates drug-induced hypotension or sedation
Many commonly prescribed medications have the potential to interact with alcohol

31. Medication Review Identify unnecessary drugs Review dose
Once daily / once weekly formulations

32. Medication Review Non-pharmacological interventions
Enlist family/friends as needed
Medication organisation equipment
Variety of healthcare professionals
Information technology

33. Patient Education Written information Take drugs as prescribed
Do not use medication from others
Report symptoms
Report all drugs used

34. Conclusion Common and growing problem
Inappropriate and appropriate prescribing
Benefits of reducing the drug burden
Regular medication review
Not always avoidable –minimise unnecessary multiple drugs