The number of patients taking two or more medicines with moderate or high anticholinergic activity increased by around 10% at the beginning of the COVID-19 pandemic and has not returned to pre-pandemic levels, show NHS data analysed by The Pharmaceutical Journal.
In a trend that experts have described as “worrying”, between January–March 2020 and April–June 2020, the number of patients in England prescribed two or more medicines with a moderate or high anticholinergic burden (ACB) score increased from 699 per 10,000 patients at risk, to 759 per 10,000 patients at risk — a rise of almost 10%.
Numbers have remained elevated since then, with the latest figures showing 734 per 10,000 patients being prescribed two or more medicines with a moderate or high ACB score in January–March 2022.
The data also show a temporary increase in associated hospital admissions. Between April–June 2020 and July–September 2020, the number of patients prescribed two or more medicines with moderate or high anticholinergic activity admitted to hospital rose from 92 to 114 hospital admissions per 10,000 patients at risk; a rise of 23%. Although admissions have since returned to pre-pandemic levels.
Medicines with high or moderate anticholinergic activity, such as the bladder drug oxybutynin, may increase the risk of constipation, confusion, a fall, or a fracture as a result of a fall, and consequently increase the risk of hospital admission.
In 2018 guidance, the National Institute for Health and Care Excellence (NICE) said that anticholinergic burden should be “minimised” in patients with suspected or confirmed dementia.
And, since October 2020, all primary care networks in England were required to target patients taking anticholinergic drugs when carrying out structured medication reviews.
The Pharmaceutical Journal analysed data from the NHS Business Services Authority’s (NHS BSA’s) medication safety indicators, which were developed to help reduce medication errors and promote safer use of medicines.
Ian Maidment, senior lecturer in clinical pharmacy at Aston University, expressed concern over the findings: “It is worrying — use of these drugs has been increasing over a long period of time and polypharmacy is generally increasing.
“These drugs cause confusion and they’ll worsen the symptoms of dementia,” he added.
Graham Stretch, chief pharmacist at the Argyle Group in west London, said that the rise could be the result of reduced contact between patients and their prescribers during the COVID-19 pandemic.
“The last thing we wanted to do was act as a vector for the infection,” he explains.
“So, then opportunities for those informal conversations with carers, or observing patients sat in a lounge, looking drowsy or sleepy or talking to relatives … were lost.
“And patients in the community haven’t been coming to the [GP] practices, they probably haven’t been coming to the pharmacy … and opportunities [there] have been lost, that previously we might have used to review medicines and discontinue them when they’re inappropriate.”
Nina Barnett, consultant pharmacist, care of older people, at London North West Healthcare NHS Trust, said she knew that some of the improvements made in reducing antipsychotics, some of which have high anticholinergic burdens, were lost during COVID-19.
“We also know that, unavoidably, the number of medication reviews reduced,” she added.
“What we don’t know is which medications were being prescribed at a higher rate that had higher anticholinergic burdens.
“It might be that because medications were added due to clinical conditions in COVID-19; for example, respiratory, diabetes and non-COVID-related conditions, and there was less opportunity for review/reduction.
“This meant that the anticholinergic burden “crept” up, due to the small but significant additive effect of medicines that, on their own, aren’t a problem but when there are existing medicines with small anticholinergic burdens, these are cumulative.”
Lelly Oboh, consultant pharmacist, care of older people, for Guy’s and St Thomas’ NHS Trust Community Health Services, said that many of the measures put in place during the COVID-19 pandemic to reduce spread of the virus could have increased the reliance on pharmacological interventions.
“Lack of contact, families not coming in, not enough staff, not enough time, and all the other things that we have put in place that are non-drug [interventions],” she added.
In June 2019, study results published in JAMA Internal Medicine showed that using strong anticholinergic medication every day for three years or more was associated with a nearly 50% increased risk of dementia in those aged 55 years and over.
Although observational, the authors said that if the associations found in the study were causal, the findings indicated that around 10% of dementia diagnoses were attributable to anticholinergic drug exposure, equating to around 20,000 of the 209,600 new cases of dementia per year in the UK.