6. CGA in Primary Care Settings: Medication review

Medication review is a core component of CGA. Older patients with multiple comorbidities can have indications for multiple medications, some of which may be based on sound, relevant evidence, but others may do more harm than good, particularly in combination. 

The evidence base for guideline-based prescribing may not be directly relevant to frail older people or those with significant comorbidity (as such people are unlikely to have been represented in trial participants). Further, even established medications may no longer be useful as diseases may have run their course, physiology may have changed, or the reason for their prescription may have been to treat another drug’s side effect (e.g. amlodipine given for a single raised blood pressure, causes ankle swelling which is treated with furosemide, which causes urinary frequency treated with tamsulosin, which causes dizziness treated with betahistine). 

Finally, many medicines are given for long-term risk reduction (e.g. hypertension, renal disease in diabetes, lipid lowering), which may be less relevant to patients with a limited lifespan, and their use may not reflect current priorities.

Judicious review of medications, their indications, side effects, benefits and interactions can cause significant and rapid improvements in a patient’s condition. This does not always involve stopping medication; indeed increasing doses to effective levels or treating patient priorities such as limiting pain may be highly beneficial, or checking whether the medication can actually be taken or not might be particularly useful (e.g. inhaler technique, ability to put in eye-drops, frequency of PRN use). Below is a schema for a general approach to medication review (it is thorough but depending on prescribing complexity can be completed in 5-10 minutes), plus some validated tools to add rigour to the process. 

1 Obtain full medication history

a.  Primary care prescription

b.  Pharmacy dispensation history

c.  Prescribed medications from other providers (e.g. private healthcare, from abroad)

d.  Other medications taken (e.g. leftover tablets, medicines prescribed for others)

e.  Herbal supplements, vitamins etc

f.  Illicit drugs

2 Review medication use: in general and for each medication

a.  In general: 

• “Are you good at remembering your pills?”
• “Can you swallow them OK?”
• “What are you most concerned about with your tablets?”

b.  For each medication:

• “Do you take this?”
• “How often?”
• “What for?”
• “Do you think it works?”
• “Does it have any side effects?”

3 Review full drug list for pharmacological interactions or common side effects

The STOPP list (see below for details) or equivalent is useful here, as well as the BNF or e-prescribing decision support to check for interactions. This will guide further questioning.
 

4 Obtain sufficient medical history

Obtain sufficient medical history and current disease status to assess appropriateness of prescribing and patient understanding, e.g.:

• If on anti-anginals: “How often do you get angina?”
• If there is a previous history of stroke: “You’re not taking a blood-thinner. Do you know why that is?”
• If on painkillers: “This tablet is a painkiller. What type of pain do you use it for? Does it work?”
• If possible issues identified eg on STOPP: “Do you suffer from constipation?”

5 Review each medication

Review each medication for appropriateness given the medical history. The MAI can be useful here, at least as a framework for evaluating the key issues related to each medication

6 List and prioritise

List and prioritise medication-related issues and discuss changes with the patient

a.  Any high-risk prescribing should be changed urgently

b.  Patient priorities are very important to both guide the process and build trust

c.  Changes should generally be introduced progressively over time unless there is a significant, urgent problem

d.  New medications should also usually be introduced one-by-one (to avoid confusion if prescribing or de-prescribing causes new symptoms)

e.  Reduce old medications gradually if necessary to avoid rebound effects (physiological or psychological dependence) and introduce new medications gradually too – start low and go slow.

f.  Arrange to assess progress and, if necessary, make further changes in the future.