The People's Perspective on Medicine

Will Low Blood Pressure Increase the Danger of Dementia in Older People?

Is lower blood pressure always better? Many people think that 120/80 is ideal but older people may be at risk for dementia if diastolic BP goes too low.

Many physicians are trained to believe that a good blood pressure (BP) is right around 120/80, regardless of age. Some aggressively prescribe several blood pressure medicines to achieve that goal. New research suggests that there could be unforeseen complications from low blood pressure in elderly patients?

The Guidelines Say Lower is Better

A cardiologist once told us that you could not have too low a golf score or cholesterol level. He was certainly correct about golf, but we think he might have been mistaken about cholesterol. It was almost as if he had convinced himself that cholesterol was a colossal mistake of nature. That despite the fact that we could not survive without cholesterol.

There seems to be a somewhat similar belief about blood pressure. Many health professionals seem to think that the lower the BP the healthier the patient. Certainly throughout middle age hypertension increases the risk for heart attacks, strokes, kidney damage and dementia. That’s why doctors often attempt to “normalize” patients’ blood pressure to 120/80.

The Dangers of Low Blood Pressure in Older People:

When it comes to the elderly, however, low blood pressure numbers may not necessarily be better. In older adults, aggressive BP control may actually lead to several serious side effects. Dizziness is not an unusual complication of drugs that produce low blood pressure. If an older person falls because he is unsteady, that could lead to a fracture. A broken hip can be a life-threatening adverse reaction.

Another problem may be accelerated mental decline. That was the conclusion from an Italian study of 172 elderly people attending memory clinics (JAMA Internal Medicine, April, 2015). The authors concluded that getting systolic blood pressure below 128 with drugs increased cognitive impairment. They recommended a range of 130 to 145 as more appropriate in the elderly.

New Research and Low Blood Pressure:

This may have seemed heretical to many physicians, but a new study appears to confirm the connection between blood pressure and cognitive function among the oldest old. Recent research focusing on nonagenarians found that those who developed hypertension late in life-no sooner than 80 and preferably after 90-actually had a lower risk of dementia (Alzheimer’s & Dementia, online Jan. 16, 2017).

The 90+ Study that provided this insight started tracking very old members of a California retirement community in 2003. By 2013, 1,554 people had volunteered for the study. None had dementia when they entered.

The researchers were able to complete a series of semi-annual in-depth in-person neurological exams on 559 of the participants. Those who developed hypertension (pressure above 140/90) after age 80 were 42 percent less likely to be diagnosed with dementia in their nineties. If their blood pressure didn’t rise until after they turned 90, they were 63 percent less likely to experience severe cognitive difficulties.

In Their Own Words:

The researchers concluded:

“In this cohort of oldest-old participants who were free of dementia into their 90s, hypertension onset late in life was associated with a lower dementia risk compared with those with no hypertension.”

Why is Low Blood Pressure Problematic?

The researchers think that by the time a person reaches an advanced age, higher blood pressure may be protecting rather than harming brain function. They suggest that higher blood pressure may help get more blood and oxygen to the aging brain. Perhaps older bodies are compensating for inadequate blood flow to the brain by boosting blood pressure. This might also offer some protection against disability and physical decline because other organs are also getting better blood flow.

What To Make of The New Research?

The new research will come as a shock to some doctors. But this is not the first time a study has shown cognitive benefit for older adults with elevated blood pressure. The Adult Changes in Thought (ACT) study found a decreased risk of dementia among people who developed hypertension after age 85 (Journal of the American Geriatrics Society, August, 2007).

Low Blood Pressure and Brain Shrinkage?

Another study offers additional evidence that low blood pressure may pose problems in certain cases (JAMA Neurology, Aug., 2013).  Dutch investigators tracked 663 patients with vascular disease for roughly four years. They had MRI scans at the start of the study and again at the end. The study revealed that people who had low diastolic blood pressure at the onset of the research had the greatest brain shrinkage (atrophy) over time.

Swedish Research on Low Blood Pressure:

Swedish researchers followed 1,270 older adults for six years (JAMA Neurology, Feb., 2003). The authors reported:

“In this elderly Swedish population, aged 75 years and older, we found that not only high systolic pressure, but also low diastolic pressure, was associated with an increased incidence of Alzheimer disease and dementia. The risk effect of low diastolic pressure on dementia was pronounced particularly among antihypertensive drug users.”

The Take Home Message on Low Blood Pressure:

Perhaps it is time to think about ideal blood pressure as changing throughout life. In fact, our blood pressure changes almost on a minute-by-minute basis depending upon our activities and mental state.

As we get older, especially in our later years, the best blood pressure goal may be a bit higher than 120/80. If an older person has low diastolic blood pressure, adding powerful blood pressure medications may increase the risk for falls and fractures because of dizziness. In addition, it may be bad for the brain.

No one should ever stop any medication without careful consultation and monitoring by a physician. This is especially true of some blood pressure drugs that could cause rebound hypertension if discontinued suddenly.

For more information about various ways to control hypertension with and without drugs, you may wish to consult our Guide to Blood Pressure Treatment. Anyone who would like a printed copy, please send $3 in check or money order with a long (no. 10) stamped (70 cents), self-addressed envelope:

  • Graedons’ People’s Pharmacy, No. B-67
  • P. O. Box 52027
  • Durham, NC 27717-2027

It can also be downloaded for $2 from the website:

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
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I suspect that if one had the financial resources to develop a cohort of people with a) clear evidence of free-flowing arteries, b) no history of the use of beta-blockers and other meds, c) no history of BP abnormalities in childhood (to age 21), d) no other cardiovascular diseases, and e) clearly determined that the walls of their arteries were not stiffening, and examined them over a goodly number of years that evidence would emerge that 120/80 might indeed be the best upper limit, even for the aged, that diet and exercise were the primary ingredients of a healthy BP, and that dementia was significantly delayed in those who managed to stay well nourished, well-exercised, and away from BP controlling drugs.

Too many unwarranted conclusions are drawn from too many studies of men and women with already degraded vascular health.

Robert Jordan Ross

I have also had low blood pressure my entire life, along with low body temperature. Doctors never gave me any advice on how to cope with it. All they would say was, “Get down on your knees and thank God you don’t have high blood pressure!” I had to learn from others about how to cope with low blood pressure.

What I learned was to pace myself, not try to keep up with others who seemed to go at break neck speed through life, and to take short naps when I felt tired or winded, even if the naps only lasted 10 or 15 minutes. I learned to take a brown bag lunch to work so that I could gobble my sandwich and then grab a nap in a corner for the rest of my lunch hour.

I finally found a chiropractor who told me that I may live longer than many of my peers because, as a result of my low vital signs, I am not using up my resources as quickly as they are. Here’s hoping that’s true. If I live into my 90s and my blood pressure does go up, I may finally have “normal” blood pressure.

Marilyn’s at 85 yrs is 110/56 and cliff’s at 75 is 110/66.
Should we go to a farm store and buy a salt block?

I am 77 years old. My normal blood pressure is 98 over 68, with no BP meds. of any kind, ever. My Dr. tells me to use salt liberally but it makes no difference. I am troubled by dizziness when I lean down but have learned to be very careful. Do you think I am at an increased risk of dementia? The only RX I take is levothyroxine, along with many supplements. My Dr. does not take it seriously. & just tells me to squat to pick up something, not lean over but it is hard & painful on the knees

The reason why higher blood pressure might be of benefit in older people is because most of them have narrowed blood vessels due to a poor diet throughout their lives, which has oxidised their surplus {above 70} cholesterol.These narrowed vessels are reducing blood flow to their organs, including the brain, Therefore most probably BP should only be tackled if it is above 150/90. This would be my practical observation on the aforementioned research, coming from a non-medically trained person but one interested in the subject.

You are probably correct. The guidelines now say that BP up to 150 systolic is fine for the geriatric population.

I have been saying this for years, low blood pressure is a good way to kill someone with arteriosclerosis, how do the cardiologists expect your body to maintain heart homeostasis by lowering your blood pressure that is needed to force the blood through the occlusions. lets face it most if not all of the elderly have arteriosclerosis and I can tell you the lesions are not caused by cholesterol!
The number one cause of death in care homes and the elderly in general in Great Britain is vascular dementia which is either caused by bleeds in the brain or lack of oxygenated blood in the brain. medicine blames the problem on high blood pressure I blame the problem on aspirin and other NSAID’s that penetrate the blood brain barrier and as well can allow for transport of other higher weight toxic molecules into the brain. As far as high blood pressure in the elderly refer to the first paragraph.
High blood pressure is a symptom that you have occluded arteries but it is NOT the cause of the occluded arteries, is there no critical thinking and common sense when it comes to modern medical practice

I’ve had low blood pressure all of my life. I’m 68 years old. Does that mean I’m going to get dementia? This is scary.

I was just thinking the same thing!!! My mom had Alzheimer’s, and her bp was normally high.

Naturally low blood pressure is probably not worrisome. We are far more concerned about people who take three or more medications to lower blood pressure and end up with a diastolic reading below 70. Please discuss your concerns with your physician.

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