Denis O’Mahony, Department of Medicine (Geriatrics), University College Cork


Prof. O’Mahony has worked at senior faculty level in the Department of Medicine at UCC since 2005, having previously worked as Senior Lecturer in Geriatric Medicine at the University of Birmingham, UK, from 1995 to 1999. He also works as a consultant physician in Geriatric Medicine at Cork University Hospital since 1999. Since the mid-1990’s, most of his research has focused on adverse pharmacotherapy in older people, its consequences and prevention. He has collaborated closely with academic colleagues in Europe, USA and Canada on research projects aimed at various ways of optimizing pharmacotherapy in multimorbid older people.

Prof. O’Mahony is the original inventor and principal developer of STOPP (Screening Tool of Older Persons’ Prescriptions) and START (Screening Tool to Alert to Right Treatment) criteria. STOPP was designed to detect potentially inappropriate medications (PIMs), START was designed to detect potential prescribing omissions (PPOs). They are embedded in a recent UK guideline for optimal recommended management of frail older people (doi:10.1093/ageing/afu138). STOPP/START criteria are also recommended in the 2015 NICE guideline on medicines optimisation in multi-morbid older people (https://www.nice.org.uk/guidance/ng5) and the current British National Formulary (volume 81, March-September 2021). STOPP/START criteria have also been endorsed by the European Union Geriatric Medicine Society, the British Geriatric Society, the UK  Royal College of General Practitioners and the Dutch government. A search of STOPP/START-related articles in PubMed in October 2021 found 851 original articles, including 72 review articles (including 30 systematic reviews) and 111 clinical studies. Articles originated from over 60 countries in Europe, North America, Asia, Australia, South America, Middle East. STOPP/START version 2 was recently translated into Chinese.

Prof. O’Mahony and his research group at UCC have also developed STOPPFrail, an explicit criteria tool to guide deprescribing in highly frail older people in their last year of life. The second version of STOPPFrail criteria and the first randomised clinical trial using STOPPFrail as an intervention were published within the last 2 years.

Since 2010, his research group in Cork has focused on randomised clinical trials of structured interventions, based largely on STOPP/START criteria, designed to minimize inappropriate prescribing in multimorbid older people and its consequences. As PI or co-PI, he has participated in 5 such clinical trials in this area, including two multicentre international trials; in total these trials have leveraged €13M in grant funding.

Prof. O’Mahony has over 200 peer-reviewed publications, including several book chapters in mainstream textbooks; details of most of these may be found at the following webpage: http://research.ucc.ie/profiles/C012/denisomahony

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