Older people using several inappropriate medications, study shows

Higher rates were recorded amongst women of 67.0% or 293,886, compared to 60.8% or 216,444 of men in this age group.

Polypharmacy is termed as the concurrent use of five or more types of medication monthly. The habit is often associated with potentially inappropriate prescribing and adverse drug interactions.

The study reveals that high levels of this habit suggest that monitoring and evaluation of patients’ medication regimes may be required to ensure appropriateness.

Increasing levels of polypharmacy have been observed internationally and in Ireland.

The Health Service Executive Primary Care Reimbursement Services (HSE-PCRS) pharmacy claims database for the General Medical Scheme (GMS) eligible population, was used as a basis for study and examined at least one claim per month dating back to 2013.

Those having lower levels of education and it is twice as likely in those who are the poorest. The study, which was published in the, Irish Medical Journal, also revealed that the use of multiple medications monthly, was also significantly associated with increasing age.

However, patients aged 45-54 years or 38.6% were less likely to have polypharmacy. This proportion rose steadily through subsequent categories up until the oldest age group of 75 years, or 82.6%.

Co-author Travis Tatum from the UCD Geary Institute for Public Policy said: “As no previous studies have looked at polypharmacy rates at the national level in the HSE-PCRS, our results establish a benchmark in this regard. Overall, rates among the GMS eligible population aged 45 years and over in receipt of any medication in 2013 was high at 64.3%.

“The study found that the availability of newer treatments and lower thresholds at which certain conditions are now treated has contributed to the increase, as have health system factors, such as mainly free access to medications, patients’ expectations of their GP and consultations with several doctors.

The use of several medications at the same time, increases the risks of developing adverse drug reactions, drug-drug interactions, hospitalisation, poor quality of life, poor medication adherence and, in some cases, death.

“The number of medications is associated with potentially inappropriate prescribing (PIP) and is associated with functional impairment and falls and fractures.”

The study examined the national rate of polypharmacy in 2013, by age and patients who remained anonymous, in the following age groups: 45-54, 55-64, 65-69, 70-74, and 75 years of age were analysed

Mr Tatum added: “Although medication can lessen the burden in the utilisation of healthcare1 by preventing costly hospitalisations and other expensive medical procedures, polypharmacy also contributes to a considerable economic healthcare burden.

“Eligible GMS patients included in the HSE-PCRS receive prescriptions at only a small co-payment (€2.50 per item). High medication use among these patients contributes to substantial government spending, especially for the oldest age groups.

“It is likely that some of the polypharmacy observed may result in potentially inappropriate prescribing and, therefore, there may be room for improvement in the quality of prescribing leading to cost-savings.”

Mr Tatum pointed out that interventions which improve the quality of prescribing would benefit patients by eliminating unnecessary costs and unwanted side-effects, which have significant health and economic implications.

“The very large number of patient cases in the PCRS database greatly strengthened the statistical power of our analysis. However, the HSE-PCRS is only a pharmacy claims database, so it was not possible to determine which medications were actually consumed; also, there was no information on the diagnoses or outcomes associated with polypharmacy,” added Mr Tatum.