The inappropriate prescribing of medications from healthcare professionals is associated with a high risk of adverse drug events in older people in Ireland. In addition, the omission of some recommended medications from prescriptions is also linked with an increased risk of having to visit an accident and emergency department.

This is according to new research from the RCSI (Royal College of Surgeons in Ireland) Department of General Practice and the HRB (Health Research Board) Centre for Primary Care Research which are the first two prospective studies in the primary care setting that examine the effect of potentially inappropriate prescribing (PIP) on outcomes for older people. The studies, in collaboration with researchers from Trinity College Dublin (TCD) were published in the Journal of Gerontology and the British Journal of Clinical Pharmacology.

These studies investigated how PIP, which is the use of a medication in a way that its risks outweigh its benefits or where a better alternative medicine exists, in people aged 65 and over, can have adverse effects on the health of older people in primary care. On the other hand, PIP can also relate to the under-use or omission of appropriate medications from a prescription.

The inappropriate prescription of medications was associated with a 29% higher rate of adverse drug events in the older people studied. The type of events reported in the research were mainly mild, such as easy bruising, difficulty stopping bleeding from a small cut, heartburn, and dizziness, while there were a few relatively severe events that led to the hospitalisation of the patient.

The studies also found that healthcare use is higher among people who are taking more than one type of inappropriate medication, as well as those not being prescribed a potentially beneficial medicine. This was linked to an increase of approximately 15% in the rate of GP visits and of approximately 40% for accident and emergency department visits.

Older people, (aged 65 years and over) are particularly vulnerable to the adverse effects of medicines because of changes that occur with ageing in how the body processes and reacts to medicines. This age group is also at increased risk as they frequently have multiple chronic medical conditions and possible interactions between drugs they take to treat their multiple conditions. Previous studies, which have mainly focused on hospitalised patients, have shown that many older people in Ireland may be prescribed potentially inappropriate medications and this can put patients at risk of harmful effects.

Some of the most frequent types of medicines being prescribed included proton pump inhibitors, a common medication for gastric problems, being prescribed to patients at high dosages for more than eight weeks; and non-steroidal anti-inflammatory drugs being prescribed long-term or to patients with high blood pressure. The most frequent prescription omissions of potentially beneficial medicines were calcium and vitamin D supplements in patients with osteoporosis and the under treatment of patients reporting an abnormal heart rhythm.

Highlighting the importance of how the quality of prescribing can have a significant impact on older people's health outcomes, Dr Frank Moriarty, lead author of one of the studies and postdoctoral researcher at the HRB Centre for Primary Care Research at RCSI, said: "Our research shows that, despite there being justification for a patient being prescribed a potentially inappropriate medication, or whose prescription contains an omitted medicine, that both lead to poorer outcomes for older patients."

At a time of unprecedented strain on our A&E departments these findings are a reminder that a range of factors can contribute to a person's risk of attending hospital. There is no single solution to this issue; however, facilitating effective management of older people's conditions, specifically improving their medicines, in primary care may make a positive contribution," he continued.

The first study, published in the Journal of Gerontology, included more than 900 patients aged 70 years and recruited from general practices in the greater Dublin area. The second, published in the British Journal of Clinical Pharmacology, included approximately 1,700 medical card patients who were participating in The Irish LongituDinal Study on Ageing (TILDA), which is a nationally-representative cohort study charting the economic, social and health circumstances of Ireland's over 50's and led by TCD. Both studies followed participants up over a two year period with interviews and questionnaires and potentially inappropriate prescribing was assessed using criteria from the Screening Tool for Older Person's Prescriptions (STOPP) and the Screening Tool to Alert doctors to Right Treatment (START).

RCSI is ranked in the top 250 institutions worldwide in the Times Higher Education World University Rankings (2016-2017). It is an international not-for-profit health sciences institution, with its headquarters in Dublin, focused on education and research to drive improvements in human health worldwide.

Journal references:

•  Journal of Gerontology - DOI: 10.1093/gerona/glw140: https://academic.oup.com/biomedgerontology/article-lookup/doi/10.1093/gerona/glw140 
• British Journal of Clinical Pharmacology - DOI: 10.1111/bcp.12995: http://onlinelibrary.wiley.com/doi/10.1111/bcp.12995/abstract