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Drug Safety and Dementia

The 14th Sidney De Haan Lecture

Professor Chris Fox presented the latest ABCD study findings at a public meeting for the 14th Sidney De Haan Lecture in Folkstone yesterday evening. Members of the public were interested in finding out more about medications that have effects on cognition.

BMJ publication - anticholinergic drugs and dementia risk

Our team findings of a history of more prescriptions of certain anticholinergic medications in patients diagnosed with dementia has been published in the BMJ today. The study used data from the Clinical Practice Research Datalink which includes anonymised diagnosis, referral and prescription records for more than 11 million patients from 674 primary care practices across the UK. We found a greater incidence of dementia among patients prescribed greater quantities of anticholinergic antidepressant, bladder drugs and antiparkinsons drugs. However we found no evidence of an increased dementia risk with anticholinergic drugs used to treat common conditions like hayfever, travel sickness and stomach cramps.

Prof Chris Fox commented “We don’t know exactly how anticholinergics might cause dementia.  Further research is needed to understand possible reasons for this link. In the meantime, I strongly advise patients with any concerns to continue taking their medicines until they have consulted their doctor or pharmacist.”

Here are some of the media stories at the BBC, the Times, the Independent, the Guardian, and CNN.

The following links provide the BMJ paper and BMJ editorial.

NIHR statistics group meeting

Dr Richardson presented a talk on her experiences managing a CPRD site licence to the NIHR statistics group on routine data in their first group meeting In London yesterday. There was great interest in the sharing of expertise and development of best practice for analysing routine data and further meetings will now be planned on these topics.  

NHS Kent and Medway CPD event

Professor Chris Fox presented latest ABCD findings on anticholinergic medications and risk of dementia in a talk called "Medication with anticholinergics effects - falls, delirium, death and cognitive impairment - The ABCD study“ at the NHS Kent and Medway Continuing Professional Development event in Kent today. 

BGS Improving continence for older people

Professor Chris Fox's presentation on ABCD findings on bladder antimuscarinics and risk of dementia was well received at the Bristish Geriatrics Society meeting on Improving Continence in Older People. This meeting was attended by healthcare professionals involved in incontinence, geriatric medicine and care of older people. 

Age UK Blog

Dr Ian Maidment writes a guest post on the Age UK blog on managing medication in later life. 

Alzheimer's Society Annual Research Conference 2017

ABCD conference poster 2017Dr Carlota Grossi recently attended the Alzheimer's Society Annual Research Conference on 18 May  2017 at the Grand Connaught Rooms, London. She presented a poster describing her work on anticholinergic and benzodiazepine use and incident dementia. 

The poster can be downloaded here:


British Pharmacological Society annual meeting 2016

combined british pharmacology posters 2016Dr Katharina Mattishent and Dr Nina Pieper recently presented the ABCD study systematic review preliminary results at the British Pharmacological Society's annual meeting in the Queen Eliazabeth II centre, London. Dr Pieper presented a poster examining anticholinergic use and incident dementia and cognitive decline. Dr Mattishent presented a poster examining benzodiazepine use and incident dementia using GP records and a poster summarising the evidence for benzodiazepine use increasing the risk of dementia.

Posters can be downloaded here: poster.pdf  poster.pdf and poster.pdf

International Conference on Pharmacoepidemiology & Therapeutic Risk Management 2016

horizontal richardson and grossi combined ICPEMembers of the ABCD study team, Dr George Savva and Dr Carlota Grossi, recently presented ABCD findings at the 32rd International Conference on Pharmacoepidemiology & Therapeutic Risk Management meeting at the Convention Center Dublin.  They presented findings on changes in anticholinergic use between 2001 and 2011, and on the association between anticholinergic use and incident dementia in a large primary care database study. The posters can be downloaded here: poster.pdf and poster.pdf

ABCD student wins award at the East Midlands Student research Conference

Declan Murphy, a medical student at UEA who joined the ABCD study team for the Alzheimer’s Society Summer School, was awarded 'Best Oral Presentation' at the East Midlands Student research Conference this month, when he presented his findings on the prescribing of benzodiazepines and Z-drugs. 

BBC radio 4 interview

Dr Chris Fox is interviewed on BBC radio 4's Inside Health on Wednesday 29th September at 9pm. He will be talking about potential adverse effects of anticholinergic medications in general and injurious falls risk in particular.


More details can be found here: 

Anticholinergic medications could delay brain injury

Members of the ABCD study team published a study today showing that the length of stay in a UK neuro-rehabilitation unit was longer for patients with acquired brain or spinal injury with a greater anticholinergic burden. 

Dr Chris Fox, lead author on the paper, said: “This pilot study demonstrates the need for larger studies to confirm the results and need for further investigation into what long-term effects these common medications are having on the recovery of these patients.”

“While medications with ACB are often needed to treat common complications of brain or spinal cord injuries, cognitive impairment due to the medication may adversely affect a patient’s ability to engage in the rehabilitation process, potentially increasing their length of stay in hospital."

Dr Ian Maidment, Senior Lecturer in Clinical Pharmacy at Aston University said: “This work adds to the evidence that anticholinergics should be avoided in a wide-range of populations, when possible. Regular medication review by a nurse, doctor or pharmacist may be a way of ensuring that medicines with anticholinergic effects are used appropriately.”

‘Does anticholinergics drug burden relate to global neuro-disability outcome measures and length of hospital stay?’ is published in the journal Brain Injury

Anticholinergic medications found to increase the risk of serious falls in men

Members of the ABCD team have found that serious falls are more than twice as likely in older men who take medicines with potent anticholinergic properties. The research team used data from the Irish Longitudinal Study on Ageing (TILDA), to discover the link between these medicines and falls which cause serious injury. The effect remained even after accounting for differences in health and other risk factors for falls. A greater use of such medicines increased the risk for these men further. There was no such association for women, however.

Lead researcher Dr Kathryn Richardson said: “Our findings indicate the importance for doctors, pharmacists and healthcare professionals to regularly review the appropriateness of medications taken by their older patients. 

“It is however, important that people don’t stop taking any medications before speaking with their GP. It is not fully clear why the same link was not found in women and further research is needed to explore this and the reasons behind the findings in men.

“Experiencing a fall can have a devastating impact on older people’s lives and is a major contributor to care home admission and hospitalisation, so it is vitally important for us to find ways to reduce the risk of falls or their severity.”

Dr Chris Fox said: “With the rising levels of frailty in older people we must develop strategies to maintain health and avoid prescribing medicines which could cause a deterioration- such an approach could be simply implemented using tools available”

Dr Ian Maidment said: “After a fall, an older person may never regain the same quality of life. This research helps us to understand how medication is linked to falls. It is vital that doctors, nurses and pharmacists review medication if someone has suffered a recent fall.”

More information is available here:

Alzheimer's Society Annual Research Conference 2015

2015 ABCD conference posterMembers of the ABCD team, Carlota Grossi and Chris Fox, recently attended the Alzheimer's Society Annual Research Conference from 29-30 June 2015 at the Mercure Manchester Piccadilly Hotel. They presented a poster describing the design of the ABCD study.


The poster can be downloaded here: poster.pdf.

Benzodiazepine use found not associated with an increased risk of dementia

In the largest study published to date using data from over 94,000 UK primary care patient records, Swiss researchers found no evidence of benzodiazepine use leading to an increased risk of dementia. They did however find evidence that benzodiazepines were more likely to be prescribed for early symptoms of dementia in up to 3 years before dementia diagnosis.

The paper can be found here:

New cellular model quantifies anticholinergic response in humans

Members of the ABCD study team, in conjunction with researchers at Aston University, have devised a cellular model that can aid the identification of anticholinergic responses to drugs in humans. It is uncertain exactly how Anticholinergic medicines affect brain processes at the cellular level and which combinations cause memory and cognition problems. In this study, the researchers used human neurones and astrocytes in the laboratory to re-create the effects of anticholinergic medicines and can now predict which combinations are likely to have the strongest negative effects on memory and cognition. This is the first time a laboratory system has been shown to be capable of reproducing a basic aspect of human brain function, so as to make constructive suggestions on safer combinations of anticholinergic medicines.

Dr Chris Fox commented that "This study graphically provides preliminary objective evidence of the impact of medications with anti-muscarinic effects, and offers us the potential to look at new assessments of the impact of medicines on this pathway and ways of mitigating their effects".

Strongly anticholinergic medications raise the risk of dementia

A new US study finds that people who took a strongly anticholinergic medication for more than three months over the past ten years were 20% more likely to get dementia. Taking them for more than 3 years resulted in a 50% increased risk of dementia (compared to people taking none). It is possible that people taking anticholinergics were already at higher risk of dementia.  This study goes a long way to addressing that possibility but cannot completely discount it. What makes the findings more convincing is that the risk of dementia increased for increasing durations of medication use.

Dr Savva, commenting in the Times newspaper, said "If strong anticholinergics increase dementia risk then there is an important opportunity to prevent dementia by discouraging their long term use. But we have to remember that anticholinergics do improve quality of life for a lot of people, and so it is important to weigh up the benefits against possible harms. It is important for individuals to discuss the benefits and harms with their doctors before stopping any medication."

Dr Fox, commenting in the Times newspaper, also added "Some of our work indications that it is also worse if you take several medications with anticholinergic effects, compared with taking one that has a strong effect." 

For more information see

Older people more likely to be prescribed antipsychotic drugs

Using UK primary care records, a study finds antipsychotics are commonly prescribed to elderly patients and more than half of these patients did not have a diagnosis for a licenced condition. This has implications for patients prescribed outside guidelines as the potiential side-effects and harms of taking antipsychotics may be greater or unknown.

See more at

New research links sleeping pills with Alzheimer's

A study published in the British Medical Journal has found that Canadian Alzheimer's Disease patients were 51% more likely to have been prescribed benzodiazepines 5-10 years before disease onset than patients without the neurodegenerative disorder.

Dr Chris Fox, a collaborator in the ABCD study, speaking to the Daily Mail said that memory problems 'are a well-known short term side-effect of benzodiazepines, but side-effects usually disappear once you stop taking them.'

'But it may be in that some people this effect is permanent.'

'What we need to find out is if benzodiazepines do cause permanent damage to the brain - is it like radiation, in that if you are exposed just once, then the damage is done?'

- See more at:

Review highlights implications of anticholinergic use

ABCD study team members have published a review of 46 studies examining Anticholinergic drug use and find evidence of their use casuing impairments in cognitive and physical function.

Dr Fox commenting for PULSE today, said "Once you start to get to five medications, you start to get increased risks of interactions and side effects, so these patients should be targeted to see if they’ve got a high anticholinergic score and then you should consider alternatives".

For more information see:

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