Problematic Polypharmacy: ‘The drugs don’t work, they just make you worse…’

Drug Policy is based on a fine balance between future benefit and harm. However, over-prescription is a growing problem: 6.5% of all hospital admissions are caused by adverse drug reactions (1), leading to increasing costs to both the patient and the healthcare system. In particular, there is a growing problem with over-prescription of antibiotics in primary care, where infections are mostly viral. This has contributed to the emergence of antibiotic resistant strains of bacteria, which has become a significant threat to patient safety.

Another example of controversy regarding over-prescription is with statins – the UK’s most commonly prescribed drugs (2).While undisputed evidence shows that they are effective in people at high risk of stroke and heart disease, for people with low risk of these conditions (3) it is unclear and whether the benefits outweigh the potential side effects (4) . This is because recommendations were made on the basis of data from clinical trials that data only assessed limited adverse effects, which were poorly characterised.

Polypharmacy

Polypharmacy is the concurrent use of multiple medications in a patient. It is largely driven by the increasing prevalence of multi-morbidity (several conditions) within the ageing population. Diabetes mellitus, hypertension, heart disease, arthritis and cancer are common in this demographic and require many medications for proper treatment. Treatments employing multiple medications can improve outcomes for patients, improve their quality of life and extend life expectancy.

As with all clinical interventions, in order to determine therapeutic efficacy or predict prognosis clinical trials are necessary; however, for medically complex older individuals this evidence base is very poor. Despite multi-morbidity being a global and widespread problem, health care systems and practice guidelines still tend to use a single-disease framework.

Polypharmacy and potentially inappropriate medication (PIM) use are thorny issues in geriatric medicine with significant clinical, economic and humanistic impacts. Problematic polypharmacy occurs when the intended benefit of medication is not realised, or multiple medications are prescribed inappropriately or unnecessarily. This may happen if a prescriber inadvertently prescribes new medication to counteract symptoms that are actually side effects caused by other medications.

Polypharmacy can increase the risk of drug interactions undermining the therapeutic benefits and the incidence of adverse drug reactions, which worsen the patient’s quality of life. A recent study on a hospitalised geriatric patient group showed that over half were prescribed PIMs (5). When medicating older patients, adverse drug reactions may occur for various reasons including: interactions with drug-drug and drug-food, improper medication administration, decreased rate of metabolism and poor patient compliance (6).Furthermore, research has shown excessive polypharmacy (6-9 drugs) as a mortality indicator in elderly populations (7).

Healthcare is a limited resource thus the appropriateness of drug use should be reviewed regularly to avoid wastage of public money. Drug expenditures are typically skewed, with the top 3% of patients prescribed excessive polypharmacy accounting for 22% of the total pharmaceutical expenditures (8). Aside from potential drug reactions and side effects, over-prescribing PIMs will occur at cost of being unable to pay for other much needed medical services.

Recognising PIM

Recognising PIM in older adults is critical, and this can achieved using explicit identification criteria, the most commonly used are the updated Beers criteria 2012 (9) and the STOPP screening tool (10).These sets of criteria vary in their ability to identify PIM use in specific settings (11-13) and they work best when used in a complementary manner (9, 10).Studies showed that these criteria not only identified a high prevalence of PIM use, but also that its use was associated with adverse drug reactions as well as functional decline (14).

Although the overall of PIM usage is estimated to be high, according to the studies carried out in the USA and Sweden there has been a decline observed in recently (15, 16). However, findings from intervention trials suggests that while the employment of such criteria reduces the level of polypharmacy and PIM use as well as drug interactions, improvement in patient outcomes such as mortality and morbidity as not been observed (17) so further refinements are clearly required.

Reviewing prescriptions regularly is important for optimal patient care, particularly as patients get older, receive more medicines, or develop more illnesses. Recently, a set of guidelines was formulated by The King’s Fund in order to promote awareness and training in medicines management, multi-morbidity and optimal polypharmacy across all levels of healthcare, whilst minimising harm and waste (18) (Box 1) .

Box 1: King’s Fund Report – key findings and recommendations (précis) (18)

Conclusion

The NHS must stay abreast of increasingly complex medical circumstances; for this a holistic approach to is needed. Furthermore, this individualised approach to healthcare should be welcomed and not viewed as a deviation from ‘best practice’ on the basis of treatment guidelines for individual diseases.

If you would like to comment on any of the issues raised by this article, particularly from your own experience or insight, Healthcare-Arena would welcome your views.

References

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