She was found on the hall floor at about seven in the morning, no memory of going down, a bruise coming up on her hip. The GP was thorough. Bloods, an ECG, a careful look at the rug. Blood pressure was taken sitting in the chair and it was, in the doctor’s words, perfect. Nobody could find a reason. The fall went into the file as a trip.
Six months later it happened again.
There is a specific, measurable, treatable thing that causes falls exactly like that one, and the test for it takes about four minutes and costs nothing. It is not a blood test or a scan. It is a blood pressure cuff used twice: once lying down, once standing up. The reason it so often does not happen is that almost everything in the Irish system, from the HSE’s own patient page to the falls screening forms used in the community, waits for you to report feeling dizzy first. And the research out of Trinity’s own ageing study says that is precisely the wrong trigger.
TL;DR
- Orthostatic hypotension is a sustained drop in blood pressure on standing: at least 20 mmHg systolic or 10 mmHg diastolic within three minutes. It is defined by the drop, not by a low number, so your readings can look completely normal.
- In TILDA data on adults aged 70 and over, about 11% had it, and two-thirds of those people had no symptoms at all. Reported dizziness did not correlate with the size of the blood pressure drop.
- Those symptom-free cases were not the harmless ones. Asymptomatic orthostatic hypotension roughly doubled the odds of an unexplained fall over six years (odds ratio 2.01).
- The dramatic head-rush most people do feel on standing is usually a different and largely benign variant. A 2026 TILDA analysis of 4,596 adults followed for eight years found it carried no increased risk of falls or blackouts.
- Two or more falls-risk-increasing medicines doubled the odds of orthostatic hypotension in Irish over-65s. The HSE’s own community falls screen only triggers a blood pressure check if you answer yes to a dizziness question.
- Ireland has no national falls strategy or clinical programme, and only four of the six regional health areas have a dedicated falls clinic.
What standing up actually asks of you
Standing is a small cardiovascular emergency that your body has been quietly managing for decades. The moment you get up, gravity pulls somewhere between 300 and 800 millilitres of blood down into your legs and the vessels around your gut. That blood is no longer available to your heart to pump, and the pressure at the top of your body starts to fall within a single heartbeat.
What stops you collapsing is a reflex loop. Stretch sensors in your carotid arteries and the arch of your aorta notice the drop and fire less often. Your nervous system reads that as an alarm, dials up the sympathetic side and dials down the parasympathetic, and your blood vessels tighten while your heart rate lifts. Meanwhile the muscles in your calves squeeze the veins and push blood back up. Done properly, the whole correction happens in seconds and you notice nothing.
Several parts of that loop get slower with age. The sensors become less responsive. Arteries stiffen, so they tighten less willingly. Thirst signalling weakens, so a degree of dehydration becomes normal rather than exceptional. And by the seventies most people are taking something that interferes with at least one step in the chain. The margin narrows, and in some people it disappears.
Two different drops, routinely confused
Here is where it gets genuinely interesting, and where most general advice goes wrong.
The first kind of drop is the one you know. You stand up too quickly from a deep chair, the room greys at the edges, you grab the doorframe for a second and then it passes. Clinically this is immediate orthostatic hypotension, a fall of more than 40 mmHg systolic or more than 20 mmHg diastolic within about fifteen seconds of standing, with recovery back towards normal by twenty seconds. It is dramatic, it is brief, and crucially it is self-correcting. You cannot detect it with an ordinary cuff at all, because it is over before a cuff can inflate. It takes beat-to-beat monitoring.
The second kind is the one you do not know. Classical orthostatic hypotension is a sustained fall of at least 20 mmHg systolic or at least 10 mmHg diastolic that is still there at one minute, two minutes, three minutes. It does not bounce back. It is less dramatic in the moment and, as we will see, very often produces no sensation whatsoever.
Almost everybody assumes the first one is the dangerous one. In July 2026, researchers from University of Galway, St James’s Hospital and TILDA published an analysis in Age and Ageing that tested that assumption properly. They took 4,596 adults aged 50 and over who had undergone beat-to-beat blood pressure monitoring during an active stand test, and followed them for eight years to see who went on to have blackouts and unexplained falls.
Both variants turned out to be common: 953 people (20.7%) had immediate orthostatic hypotension and 1,008 (22.0%) had the classical form. Roughly one in five each.
The outcomes diverged. Over eight years, blackouts or unexplained falls were reported by 15% of the classical group, 9.5% of the immediate group, and 9.6% of those with neither. After adjusting for age, sex, education, cardiovascular disease, diabetes, baseline blood pressure and heart rate, frailty and number of medicines, classical orthostatic hypotension was independently associated with blackouts or unexplained falls (odds ratio 1.31, 95% confidence interval 1.04 to 1.66). Immediate orthostatic hypotension was not (1.22, 0.93 to 1.57). For unexplained falls specifically, the classical form came out at 1.42 (1.09 to 1.84) and the immediate form at 1.14, which is statistically indistinguishable from no effect. Among those aged 65 and over, the classical form rose to 1.66 (1.20 to 2.30).
The authors’ conclusion is worth reading slowly: immediate orthostatic hypotension “may represent a benign physiological response”. The group who had it were younger, fitter, less frail, on fewer medicines, and median age 57 against 64 for the classical group.
In plain terms: the whoosh you feel standing up from the sofa is probably your circulation working hard and winning. The drop that eventually puts someone on the hall floor is a quieter one.
Two honest caveats. Neither variant was associated with falls overall, with falls requiring medical attention, or with fracture in that analysis. The signal is specifically in unexplained falls and blackouts, which is exactly the category that tends to get written off as a trip. And an association is not a cause. What this evidence supports is looking, not panic.
The part that should change how you ask
If the dangerous variant were reliably uncomfortable, symptom questions would be a reasonable filter. It is not.
A 2022 TILDA analysis in Age and Ageing looked at adults aged 70 and over who had continuous blood pressure measured during an active stand. Just under 11%, some 934 people with a mean age of 75, met the criteria for orthostatic hypotension. Two-thirds of them reported no symptoms.
It goes further than that. The researchers tested whether reported dizziness tracked the size of the blood pressure drop at 30, 60 and 90 seconds after standing. It did not, at any of the three time points. Feeling light-headed told you nothing useful about how far your pressure had actually fallen.
And the people with no symptoms were not the lucky ones. Over six years of follow-up, asymptomatic orthostatic hypotension was independently associated with unexplained falls, odds ratio 2.01 (1.11 to 3.65). It was not associated with explained falls, the ordinary trips over the step and the loose flex, which is exactly the pattern you would expect if the mechanism is real.
So the single most common way of deciding whether to check someone, asking whether they feel dizzy when they stand, selects for the benign variant and misses two-thirds of the dangerous one.
What the check actually is
Lying and standing blood pressure is not a specialist investigation. Any practice nurse can do it and so, with a home monitor and a bit of patience, can you.
Lie flat and rest for at least five minutes, ideally ten. Have your blood pressure taken lying down. Then stand up and have it taken again at roughly one minute and again at three minutes, with the cuff at heart level and your arm supported. A sustained fall of 20 mmHg or more in the top number, or 10 mmHg or more in the bottom number, meets the definition.
Notice what that definition does not say. It says nothing about the absolute numbers. Someone who reads 162/88 lying down and 138/76 standing has textbook orthostatic hypotension and two readings a GP would be pleased with. Someone whose lying pressure is already low may have no postural drop at all. The diagnosis lives in the difference, and you can only see a difference if somebody measures twice.
This is where the HSE’s own patient information works against you. Its page on low blood pressure mentions postural hypotension in exactly one sentence, and defines it by feel: “You may get symptoms when you stand up or suddenly change position. If you do, you may have postural hypotension.” Its advice on when to act is symptom-gated too: “Get your blood pressure checked if you keep getting symptoms.” It offers three ways to have that check done, by your pharmacist, by your practice nurse or GP, or at home on your own monitor, and not one of them involves measuring in two positions. And it tells you, in bold terms, that “low blood pressure is a measurement of 90/60mmHg or lower”, a fixed threshold that has nothing to do with a postural drop and that the woman in the hall would never have met. The page, to be fair to it, carries a note saying the content is supplied by the NHS and adapted for Ireland.
The pattern repeats in clinical documents. Take the falls care pathway published by HSE Mid West Community Healthcare, a guideline running to over ten thousand words. Its falls screening tool asks “Did you feel dizzy before you fell?” and “Do you feel dizzy when you get up after sitting or lying?” Tick yes to either and the form directs staff to arrange a postural hypotension check with the GP. Tick no, which is what two-thirds of people with the condition would do, and nothing is triggered. The document’s own description of postural hypotension lists six symptoms and no measurement protocol at all. It was published in November 2021 with a revision date of November 2023.
The medicines question
If there is one modifiable cause worth chasing, this is it.
STOPPFall is a screening tool that collates fourteen classes of medicine known to increase falls risk in later life. The list is long and extremely ordinary: benzodiazepines, the Z-drugs used for sleep, antipsychotics, opioids, antidepressants, antiepileptics, diuretics, alpha-blockers used for blood pressure, alpha-blockers used for an enlarged prostate, centrally-acting blood pressure medicines, antihistamines, nitrates and other cardiac vasodilators, medicines for urinary frequency and incontinence, and drugs with strong anticholinergic effects.
A 2025 analysis in Age and Ageing applied that list to 1,499 TILDA participants aged 65 and over who had undergone active stand testing. About 27% were on one of these medicines and 10.6% were on two or more. Being on two or more was independently associated with more than double the odds of classical orthostatic hypotension (odds ratio 2.07, 1.13 to 3.78), and with significantly delayed blood pressure recovery after standing (1.88, 1.25 to 2.82). Measured directly, that group’s systolic pressure sat almost 8 mmHg lower at thirty seconds after standing than people on none.
Two things follow. First, if you are on two or more of these, a lying and standing reading is worth asking for even with no symptoms and no falls. Second, and this matters, the finding runs the other way too: this is a cause that can often be removed. Doses can be adjusted, timings moved, duplicates stopped. That is a conversation with your GP or pharmacist, not a decision to make at the kitchen table. Never stop a prescribed medicine on your own, including one you are fairly sure is the culprit.
Once is not enough
One more thing the research is blunt about. A single normal lying and standing reading does not rule the condition out.
A 2026 study in Clinical Autonomic Research repeated orthostatic blood pressure measurements in the same people a year apart and found reproducibility was modest for the systolic response and poor for the diastolic one. Of the nine participants who met the criteria for orthostatic hypotension at the repeat visit, not one of them had met the criteria at baseline. The researchers’ recommendation is explicit: repeat the measurement rather than relying on a single reading, and re-measure at every visit in people at risk. TILDA’s own earlier work, which identified eight distinct patterns of blood pressure behaviour on standing, found the same instability when people were re-tested after four years.
The condition is also worse first thing in the morning, after a night lying flat and before you have had anything to drink. If you can choose, choose a morning appointment.
The Irish context
It would be easier to be relaxed about all this if falls were rare. They are not.
Researchers analysing TILDA Wave 6 data and scaling it against the 2022 census published their findings in BMJ Open in 2026. Among people aged 70 and over living in the community, almost 12% had a fall requiring medical attention in a single year. Extrapolated nationally, that is around 61,998 people. Roughly 32,207 attended an emergency department after a fall. Over 3% sustained a fracture. Among those aged 85 and over, more than 8% had a fracture in twelve months.
Their conclusion included this sentence: “Currently, there is no national falls strategy in Ireland.” They also noted that there is no dedicated clinical programme for falls, that only four of the six proposed regional health areas were served by a dedicated falls clinic, that four of those six clinics are in Dublin, and that consequently more than a fifth of older people presenting to an emergency department after a fall cannot access a local multidisciplinary falls service.
That is the backdrop against which a four-minute measurement matters. Where there is no national programme making something routine, it falls to individual clinicians to remember and to individual patients to ask. Ireland does genuinely excellent research on this, much of it from TILDA at Trinity and the falls and syncope service at St James’s. The gap is not knowledge. It is the distance between what the Irish evidence says and what the forms ask.
What to do with this
Ask for the measurement by name. “Could I have a lying and standing blood pressure?” is the request. Ask for it after any fall you cannot fully explain, after any blackout, if you are on two or more of the medicine classes above, and as part of any annual review once you are in your seventies. You do not need to have symptoms to ask, and you should not wait to develop them.
Bring the full list. Everything prescribed, everything bought over the counter, everything you take occasionally. Antihistamines and sleep aids bought in a pharmacy belong on that list.
Keep a note of unexplained falls. Date, time of day, what you were doing in the minute beforehand, whether you remember going down. Falls in the hour after a meal or in the first few minutes after getting out of bed are patterns worth flagging. If you lost consciousness, read our guide to fainting and blackouts after 50, because that changes the urgency and has implications for driving.
If you are diagnosed, the fixes are mostly unglamorous. Rise in stages and sit on the edge of the bed for a minute before standing. Keep fluids up, especially in hot weather or during illness. Eat smaller, more frequent meals if the trouble clusters after eating. Raising the head of the bed by about 15 centimetres helps some people, and compression stockings help others. Ask before changing salt or fluid intake, because that advice reverses entirely if you have heart failure. Our guides to falls prevention and dizziness and balance after 50 cover the strength and balance side, which does as much work as anything on this list.
If the first reading is normal, ask for it again. Particularly if the falls continue.
The point worth holding onto
The instinct behind “but she was never dizzy” is a decent one. We use symptoms as a guide to seriousness in almost every other part of medicine, and most of the time that works. Orthostatic hypotension is one of the places it quietly fails, and the Irish data showing that is some of the clearest in the world.
If you take one thing from this, make it this: a blood pressure reading taken sitting in a chair, however good it looks, has not answered the question. The question is what happens to that number thirty seconds after you stand up, and the only way to know is to measure it. At Críonna Health we write about ageing as something to navigate well rather than endure quietly, and this is one of the better examples going. The condition is common, the test is free, the causes are often sitting in the medicine press, and the main thing standing between a person and the answer is that nobody thought to take the cuff out twice.
This article is for general information and is not a substitute for individual medical advice. If you have had an unexplained fall or blackout, speak to your GP. Never stop or change a prescribed medicine without medical advice.
📷 Photo by Susan Wilkinson on Unsplash
