Amrita is in her 80s, lives in a house with 4 generations of her family but currently in a my consulting room in a wheelchair, and for the past year has struggled with lethargy, somnolence, walking and even conversation, often seeming a little confused. We’ve all put it down to getting old, but could there be more to it?
A new paper, published in this month’s BJGP (2025;75(760):e786), highlights the rate of delirium amongst older people living in their own homes. When we think about delirium, I suspect most of us would assume it is relatively uncommon and mostly linked with acute illness, and probably in a person in residential care. But as the researchers point out, there is a huge knowledge gap about how our patients living at home may be affected by unrecognised delirium and ask the question:
Could delirium be significantly more common than we think?
The authors undertook a systematic review of existing studies reporting on delirium in people living at home, with their primary aim to determine how common this may be. They identified 24 studies for inclusion but noted a significant amount of heterogeneity both in how these studies examined for delirium and the reported prevalence – from 0.2% to 8.3% in general community-dwelling older populations (≥65y), and from 1.4% to 44% in those with frailty (a major risk factor) receiving care at home.
The key reason for this difference is whether the studies specifically screened for delirium using a validated tool or simply pulled the diagnosis from existing healthcare data. The clear implication is when we go looking for it, delirium is much more common than we might think.
Colloquially often termed “acute brain failure”, delirium often presents in two distinct ways. “Hyperactive” is the easier form to recognise; these are our restless, anxious, agitated patients. “Hypoactive” is where things get more difficult as patients may have subtler symptoms: lethargy, drowsiness, being ‘pleasantly confused’. Despite being more common, hypoactive delirium is less likely to be diagnosed.
By definition, delirium is considered an acute condition, but researchers are exploring the idea of persistent delirium. A 2022 systematic review and meta-analysis update identified that at least 1 in 8 older patients continued to display symptoms of delirium 12 months after hospital admission. While there is no data on duration of delirium in community populations, this makes me think about many of my frail patients, my housebound patients. Could there be more to their symptoms – that mild confusion, that excessive somnolence? Could they essentially have chronic delirium?
Back to our patient, Amrita then. She sleeps a lot and intermittently talks nonsense to her family. She often can’t stand or balance well. She is on several medications: amlodipine, indapamide, metformin, gliclazide, atorvastatin and tolterodine being the most relevant.
Recent bloods show a mild hyponatraemia. Her HbA1c is 49mmol/mol (6.6%) but her finger prick BMs show she is often borderline hypoglycaemic. Her blood pressure is 120/80 as she sits in her chair, but drops when she tries to stand. She is frequently incontinent of urine, which in fact may be worse since she started the tolterodine.
Medications are one of the most common causes of delirium, and while acute changes to a patient’s cognitive state can be easily recognised, longer term, lower level changes are easily missed.
Amrita has multiple iatrogenic drivers of delirium. We decide to focus on the person rather than the numbers. Stopping the indapamide resolves the hyponatraemia, stopping the gliclazide resolves the hypoglycaemia, stopping the tolterodine reduces her anti-cholinergic burden and the combination results in marked improvements in cognition, energy and mobility.
Time for us to start thinking about delirium more, but if you’re looking for even more urgent care problems, join us on the Saturday 15th November for our brand new Urgent Care course. We’ll be covering a wide range of acute medical problems that present in general practice and community urgent care settings including management of syncope, acute chest pain, acute asthma, acute facial pain, and much, much more.

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