A new study has found that several commonly used drugs could significantly reduce the risk of delirium in older people following surgery.
Delirium – a sudden state of confusion and memory problems – affects around one in seven older adults after an operation. People who get delirium spend longer in hospital, are more likely to die in hospital or develop dementia later in life.
The study, published in The BMJ, was conducted by researchers at the University of Oxford’s Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS) and Nuffield Department of Clinical Neurosciences (NDCN), the University of Birmingham and supported by the National Institute for Health and Care Research (NIHR) Oxford Biomedical Research Centre.
The principal author, NIHR Doctoral Research Fellow Dr Matthew Luney, said: “Delirium is often unpleasant and distressing – for patients and their loved ones. It can slow recovery, lengthen hospital stays and often lead to long‑term health problems. This study brought together a great deal of existing research to help us identify which medications might help to prevent it after surgery.”
The research team analysed 158 clinical trials involving more than 41,000 participants aged 60 and over, using a ‘network meta‑analysis’ to compare the medicines and evaluate how effective each of them was.
They found that dexmedetomidine, a painkiller and sedative that also reduces inflammation, prevented delirium in almost every type of surgery. It reduced the number of people with delirium after surgery from 14 to seven per 100 people.
Several other medicines worked in specific types of surgery but often only in smaller studies. These included: corticosteroids; melatonin receptor agonists (which help to regulate sleep); Parecoxib, an anti‑inflammatory drug used to manage post-operative pain; Olanzapine, an antipsychotic medication; and intranasal insulin.
The type of anaesthetic used during surgery had minimal effect on whether delirium was prevented. Time spent in hospital and deaths after surgery were not different whether people had treatment to prevent delirium or not.
Dr Luney said: “It was very encouraging to see the effects dexmedetomidine – a drug often used during surgery – had in reducing delirium in patients after their operation. There were a number of other medications that appear promising, although more rigorous research will be needed before we can draw any conclusions about their merits.
Professor Matthew Costa, Professor of Orthopaedic Trauma Surgery in NDORMS and Oxford BRC Musculoskeletal Theme Lead, said: “With older adults making up a growing proportion of surgical patients, preventing delirium is increasingly important – it will help patients recover more quickly, lower healthcare costs and improve quality of life for our patients.
“Coming soon after the establishment of the Kadoorie Institute for Trauma, Emergency and Critical Care, it is significant that this piece of work brought together experts from the NDORMS and NDCN – the two departments that created the institute – to deliver research that promises to improve patient outcomes.”
Professor Costa is leading a related study, which is investigating whether anti-tumour necrosis factor (TNF) therapy, used to tackle inflammatory conditions, can reduce or prevent delirium following surgical operations.