Appropriate and problematic polypharmacy

Patients might be prescribed a large number of medicines, but it doesn’t mean that those medications are inappropriate.

As a consequence, polypharmacy may be defined as appropriate or inappropriate¹.

APPROPRIATE Polypharmacy:

• Drugs prescribed for the purpose of achieving a specific therapeutic objective that has been agreed with the patient; where the medicines are prescribed according to best evidence and achieve the intended goals.

PROBLEMATIC Polypharmacy:

• When multiple medications are prescribed inappropriately, or where the intended benefit of the medication is not realised.
• Describes when the downsides of using particular medicines outweigh the (potential) benefits.

So what evidence is there of appropriate polypharmacy?

Well a common example you may encounter in practice is a patient discharged on multiple new medications after an acute admission with a myocardial infarction. The table below highlights research demonstrating a 75% cumulative relative-risk reduction from taking four drugs for secondary prevention in cardiovascular disease^{1, 2}.

Figure 1: Reducing relative and absolute risk through polypharmacy. Table adapted from source², where there are details of how cumulative risk reduction was calculated.

Polypharmacy has been strongly associated with unplanned hospitalisation, though this effect is actually reduced in people with multiple conditions, who are less likely to experience an unplanned admission³. Only the most extreme levels of polypharmacy in people with multiple health problems were found to be associated with increased hospital admissions. Therefore, it can be wrong to assume that polypharmacy is always hazardous or represents poor care.

Therefore, simply reducing the number of medicines isn’t the solution. A flexible approach accounting for the clinical context and patient preferences is key.

We’ve considered how appropriate polypharmacy can definitely be beneficial. However, Brian’s case may tell a different story of problematic polypharmacy.

Past Medical History

• Hypertension
• Type 2 diabetes
• Osteoarthritis
• Overactive bladder
• Depression
• Gout
• Dry eye syndrome
• Constipation

Medication

• Ramipril
• Indapamide
• Metformin
• Amitriptyline
• Co-codamol 30/500
• Oxybutynin
• Allopurinol
• Citalopram
• Systane eye drops
• Fybogel
• Atorvastatin

Let’s consider Brian’s medications above. With all the interactions we identified earlier, he certainly has the potential for problematic polypharmacy. So if you encountered Brian in practice, where would you start?

You may have spotted that his gout could have been precipitated by his indapamide, so your priority may be to review this. However, Brian’s priority could be to reduce his constipation, which may have been triggered by his oxybutynin, amitriptyline or co-codamol. If we stopped these, it could negatively impact on his other conditions, including his osteoarthritis and overactive bladder. Where do we start?!

Ideally we want to tailor our de-prescribing, taking account of Brian’s priorities, whilst using our own wisdom to guide decision making. This is where understanding some of the potential barriers to tailored de-prescribing and having a structured approach could help!

We’ll consider this further in the coming steps…

References

1. The King’s Fund. Polypharmacy and Medicines Optimisation: making it safe and sound. 2013. Available from: https://www.kingsfund.org.uk/publications/polypharmacy-and-medicines-optimisation [Accessed 17/02/2022]
2. Yusuf S. ‘Commentary: Two decades of progress in preventing vascular disease’. The Lancet. 2002; 360:2-3.
3. Payne RA, Abel GA, Avery AJ, Mercer SW, Roland MO. Is polypharmacy always hazardous? A retrospective cohort analysis using linked electronic health records from primary and secondary care. Br J Clin Pharmacol. 2014 Jun; 77(6): 1073–1082. DOI: 10.1111/bcp.12292