Earlier Onset of High Blood Pressure Affects Brain Structure, May Increase Dementia Risk


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Individuals who are diagnosed with high blood pressure at ages 35-44 had smaller brain size and were more likely to develop dementia compared to people who had normal blood pressure, according to new research published in Hypertension, an American Heart Association journal.

The results raise the possibility that taking steps in young adulthood to control or delay the onset of high blood pressure may reduce the risk of dementia.

“Hypertension is very common in middle-aged people (45-64 years), and early onset high blood pressure is becoming more common. Although the association among hypertension, brain health and dementia in later life has been well-established, it was unknown how age at onset of hypertension may affect this association. If this is proven, it would provide some important evidence to suggest earlier intervention to delay the onset of hypertension, which may, in turn, be beneficial in preventing dementia,” said Mingguang He, M.D., Ph.D., senior author of the study and professor of ophthalmic epidemiology at the University of Melbourne in Melbourne, Australia.

The researchers analyzed data from participants in the UK Biobank, a large database containing detailed anonymous health information of about half a million volunteer participants in the United Kingdom. To determine brain changes, they compared magnetic resonance imaging (MRI) measurements of brain volume between two large groups of adults in the database: 11,399 people with high blood pressure diagnosed at different ages (younger than age 35; 35-44 years; and 45-54 years), and 11,399 participants who did not have high blood pressure, matched for age and multiple health-related variables. Participants entered the databank between 2006 and 2010, and they had MRI brain scans between 2014 and 2019. Hypertension in this study was defined as reporting a diagnosis of hypertension (told by a doctor) or inpatient records using the codes for international classification diseases. The blood pressure reading at the time of their MRI scans was controlled in the analysis.

From the MRI scans, the investigators found:

  • In each diagnostic age category (from 35 to 54), the total brain volume was smaller in people diagnosed with high blood pressure, and the brain volume of several regions were also smaller compared to the participants who did not have high blood pressure;
  • Hypertension diagnosed before age 35 was associated with the largest reductions in brain volume compared with controls; and
  • Among people with normal blood pressure readings at the time of their MRI scans, those who were previously diagnosed with hypertension at <35 years old had smaller total brain volume compared to people with normal blood pressure who had never been diagnosed with hypertension.

“Individuals who had hypertension diagnosed at younger ages had smaller brain volumes on these one-time measurements. Future research with brain volumes measured at multiple time points could confirm whether hypertension diagnosed at a younger age is associated with a greater decrease in brain volume over time,” said Xianwen Shang, Ph.D., M.P.H., lead author of the study and a research fellow at the Guangdong Provincial People’s Hospital in Guangzhou, China.

To evaluate dementia, the investigators examined how many participants developed dementia from any cause over a 11.9-year follow-up period, comparing 124,053 people with high blood pressure and 124,053 matched adults who did not have high blood pressure. During the follow-up period (up to 14 years; median of 11.9 years), 4,626 people developed some form of dementia. Analyzing the occurrence of dementia in relation to blood pressure diagnosis, the researchers found:

  • The risk of dementia from any cause was significantly higher (61%) in people diagnosed with high blood pressure between the ages of 35 and 44 compared to participants who did not have high blood pressure.
  • The risk of vascular dementia (a common form of dementia resulting from impaired blood flow to parts of the brain, as might happen after one or more small strokes) was 45% higher in the adults diagnosed with hypertension between ages 45-54 and 69% higher in those diagnosed between ages 35-44, compared to participants of the same age without high blood pressure.
  • Although vascular dementia risk was 80% higher in those diagnosed with high blood pressure before age 35, there were fewer cases of dementia among the younger participants, and the association with high blood pressure was not statistically significant, whereas the risk association was meaningful for individuals ages 45-54 with high blood pressure.
  • In contrast to vascular dementia, no relationship was found between age at hypertension diagnosis and the risk of Alzheimer’s disease, a type of dementia linked to proteins that disrupt brain function.

“Our study’s results provide evidence to suggest an early age at onset of hypertension is associated with the occurrence of dementia and, more importantly, this association is supported by structural changes in brain volume,” said Shang. The findings raise the possibility that better prevention and control of high blood pressure in early adulthood could help prevent dementia.

“An active screening program to identify individuals with early hypertension and provide earlier, intensive high blood pressure treatment might help reduce the risk of developing dementia in the future,” said He.

In future research, the investigators are planning to examine medical records to detect whether the onset of dementia was preceded by other medical conditions with previously established connections to dementia risk, such as diabetes or stroke, in people who developed high blood pressure during young adulthood or middle age. Results from this study of a predominantly Caucasian population are not necessarily generalizable to people from other racial or ethnic groups.

Source: American Heart Association

Healthy Changes in Diet, Activity Improved Treatment-resistant High Blood Pressure

People with treatment-resistant hypertension successfully reduced their blood pressure by adopting the Dietary Approaches to Stop Hypertension (DASH) eating plan, losing weight and improving their aerobic fitness by participating in a structured diet and exercise program at a certified cardiac rehabilitation facility, according to new research published today in the American Heart Association’s flagship journal Circulation.

Uncontrolled high blood pressure (130/80 mm Hg or higher) despite the use of three or more medications of different classes including a diuretic to reduce blood pressure is a condition known as resistant hypertension. Although estimates vary, resistant hypertension likely affects about 5% of the general global population and may affect 20% to 30% of adults with high blood pressure. Resistant hypertension is also associated with end-organ damage and a 50% greater risk of adverse cardiovascular events, including stroke, heart attack and death.

Diet and exercise are well-established treatments for high blood pressure. In June 2021, the American Heart Association advised that physical activity is the optimal first treatment choice for adults with mild to moderately elevated blood pressure and blood cholesterol who otherwise have low heart disease risk.

This new study, Treating Resistant Hypertension Using Lifestyle Modification to Promote Health (TRIUMPH), is the first to evaluate the impact of lifestyle modifications in people with resistant hypertension. Researchers found that behavioral changes, including regular aerobic exercise, adoption of the DASH (Dietary Approaches to Stop Hypertension) diet, reducing salt consumption and losing weight, can lower blood pressure significantly and improve cardiovascular health in people with resistant hypertension. The DASH eating plan is rich in fruits, vegetables, low-fat dairy products and limited salt, and aligns with the American Heart Association’s nutrition recommendations.

The four-month clinical trial involved 140 adults with resistant hypertension (average age 63; 48% women; 59% Black adults; 31% with type 2 diabetes; and 21% with chronic kidney disease). Participants were randomly divided into two groups – 90 participants received weekly dietary counseling and exercise training in an intensive, supervised cardiac rehabilitation setting three times a week. The other 50 participants received a single informational session from a health educator and written guidelines on exercise, weight loss and nutritional goals to follow on their own.

Researchers found:

  • The participants in the supervised program had about a 12-point drop in systolic blood pressure, compared to 7 points in the self-guided group. Systolic blood pressure (the first number in a blood pressure reading) indicates how much pressure blood is exerting against artery walls when the heart beats and is recognized as a major risk factor for cardiovascular disease for adults ages 50 and older.
  • Blood pressure measures captured through 24 hours of ambulatory monitoring during a typical day revealed that the group in the supervised lifestyle program had a 7-point reduction in systolic blood pressure, while the self-guided group had no change in blood pressure.
  • Participants in the supervised program also had greater improvements in other key indicators of heart health, suggesting that they had a lower risk of a heart event in the future.

“Our findings showed lifestyle modifications among people with resistant hypertension can help them successfully lose weight and increase their physical activity, and as a result, lower blood pressure and potentially reduce their risk of heart attack or stroke,” said James A. Blumenthal, Ph.D., first and senior author of the study, and J.P. Gibbons Professor of Psychiatry and Behavioral Sciences at Duke University School of Medicine in Durham, North Carolina. “While some people can make lifestyle changes on their own, a structured program of supervised exercise and dietary modifications conducted by a multidisciplinary team of health care professionals in cardiac rehabilitation programs is likely more effective.”

Blumenthal noted that the success of the supervised program doesn’t mean people with resistant hypertension can stop taking their medications; however, it suggests that they may want to talk with their physicians about possibly reducing the dosages or altering their medications based upon their lowered blood pressure values.

The study was conducted at a single institution – Duke University School of Medicine – so findings may not be generalizable to broader groups of people. However, the intensive, structured, supervised part of the study occurred at several representative cardiac rehabilitation centers in central North Carolina, with educational and cultural diversity well represented. Researchers believe the program could be implemented with success at similar cardiac rehabilitation centers throughout the county. Also, the study’s impact beyond the four months of monitoring is limited by whether participants who made significant lifestyle changes will maintain them. “The benefits of the lifestyle modifications may be reduced unless the healthy lifestyle habits can be maintained,” Blumenthal said.

“The most important point is that it is not too late to lower blood pressure by making healthy lifestyle choices,” he said. “Adopting a healthy lifestyle pays huge dividends, even for people whose blood pressure remains elevated despite being on three or more antihypertensive medications.”

American Heart Association volunteer expert Bethany Barone Gibbs, Ph.D., FAHA, noted that this data gives clinicians another evidence-based tool for helping patients with resistant hypertension.

“Though we usually think about recommending lifestyle changes like losing weight and getting more physical activity before starting medications, this study provides important reinforcement that adding lifestyle changes in conjunction with medications – and when medications alone are not doing the job – is an effective strategy,” said Gibbs, an associate professor in the department of health and human development and clinical and translational sciences at the University of Pittsburgh. “Also exciting is that Blumenthal, et. al., used a cardiac rehab model, which can be duplicated in many settings.”

Gibbs, chair of the statement writing group of the Association’s June 2021 scientific statement on lifestyle treatment for hypertension, urged patients to commit to lifestyle changes – losing 5% to 10% of their bodyweight, greater adherence to the DASH-style diet, and increasing steps by at least 1,000 per day can yield health benefits.

Source: American Heart Association

Can Isometric Resistance Training Safely Reduce High Blood Pressure?

Emi Berry wrote . . . . . . . . .

This very accessible and easy to perform intervention could have a strong effect on reducing blood pressure, say UNSW Sydney researchers.

When was the last time you had your blood pressure checked? High blood pressure affects 1.13 billion people around the globe and in 2019, it accounted for 10.8 million deaths. Worldwide, it’s the leading risk factor for mortality. More than a third of the Australian population over the age of 18 has high blood pressure, yet it’s estimated 50 per cent of Australians don’t realise they’re living with it.

As high blood pressure puts you at high risk of having a heart attack or stroke (cardiovascular disease), it’s important to keep track of your blood pressure. People over the age of 18 are advised to have a blood pressure check at least every two years.

Given the impact of this global health challenge, there is a clear need for strategies to reduce the prevalence and severity of high blood pressure, and exercise is one such strategy. While aerobic and dynamic resistance exercise appears effective at reducing blood pressure, a new study led by UNSW Medicine & Health researchers has revealed isometric resistance training (IRT) as an emerging mode of exercise demonstrating effectiveness in reducing office blood pressure. Office blood pressure refers to your pressure when taken during a GP visit, for example. It is taken at one time period, usually when you’re sitting down.

What is isometric resistance training?

IRT is a type of strength training. During IRT, the muscles produce force but do not change length. For example, pushing against a wall or holding a ‘plank’. This is different to more traditional strength training like a squat or a push-up or where muscles shorten and lengthen during the movement.

Currently, IRT is not recommended by several international guidelines for the management of high blood pressure. This was mostly due to concerns over its safety because the static nature of IRT causes blood pressure to increase markedly during exercise, particularly when performed using large muscle groups or at high intensity, compared to traditional strength exercise such as lifting weights or aerobic exercise such as walking or cycling.

However, lead authors of the study Mr Harrison Hansford and Dr Matthew Jones, both accredited exercise physiologists at the School of Health Sciences said their research showed IRT to be safe.

“We were interested in how IRT reduced blood pressure in people with high blood pressure. We also wanted to know whether IRT was safe. We found that IRT was very safe and caused meaningful changes in blood pressure – almost as much as what you’d expect to see with blood pressure-lowering medications,” explained Dr Jones.

He said exercise is important for the management of high blood pressure, but the researchers acknowledged many Australians were physically inactive, with ‘lack of time’ commonly cited as a reason.

“IRT is a time-efficient means of reducing blood pressure, needing only 12 minutes a day, two to three days per week to produce the effects we found in our review.”

“While the studies included in our review normally used a specialised handgrip device, it’s possible we would see the same effects simply by asking participants to make a fist and squeeze it at a certain intensity for the prescribed amount of time. This means IRT could easily be performed while participants are sitting down watching TV,” said Dr Jones.

“We also found IRT caused improvements in other measures of blood pressure including central blood pressure (the pressure in the heart’s largest artery – the aorta, and an important predictor of cardiovascular disease) and to a lesser extent ambulatory blood pressure (average blood pressure across a 24-hour period), neither of which had previously been reviewed.”

Although previous studies had shown IRT as being effective for lowering office blood pressure, the studies had not comprehensively examined the safety of IRT.

IRT is accessible and easy to perform

Dr Jones said IRT is a very accessible and easy to perform intervention. He highlighted how exciting it was to know such a simple intervention could have such a strong effect on reducing blood pressure – the leading risk factor for mortality, globally.

“It’s particularly exciting for people who may have difficulty performing more ‘traditional’ exercise such as walking, cycling or strength training knowing they have another exercise type in their toolkit to help manage their high blood pressure.”

Dr Jones noted the research team were surprised there were not increased risks of adverse events in older adults.

“In fact, there were actually lower rates of adverse events in older adults, making it a very appealing mode of exercise, especially in those with mobility restrictions who may not be able to do other exercises like aerobic or dynamic resistance training.”

Dr Jones acknowledged research limitations in terms of the studies included in the scientific literature review, which were not always of ‘high quality’. This means the research team cannot be entirely confident in their results. Dr Jones also acknowledged relatively few studies examined lower body IRT, or IRT using different doses and intensities. Therefore, it is still unclear how different types and doses of IRT may affect results, and whether these would also be safe.

“There is a clear need for large, high-quality randomised controlled trials to better assess the effect of IRT on blood pressure. To conduct such a study would be a clear goal for the future. It would also be useful to study how different types and doses of IRT affect results, and whether this differs between males and females, so this would also be a goal of future research.”

Source: UNSW Sydney

Statins May Reduce Death from, Severity of COVID-19 Among Those with Heart Disease or High Blood Pressure

Research published today in The Public Library of Science ONE, PLOS ONE, examined the relationship between use of medications to control cholesterol or blood pressure levels, and the risk of death among people who were hospitalized due to COVID-19.

In an analysis of more than 10,000 hospitalized COVID-19 patients across the United States, the use of cholesterol-lowering drugs, known as statins, prior to admission was associated with a more than 40% reduction in in-hospital death, and a greater than 25% reduction in the risk of developing a severe outcome. The analysis compared similar patients who did and did not use statins or anti-hypertensive medication, among those both with and without underlying health conditions.

“Early during the pandemic, there were questions as to whether certain cardiovascular medications might worsen COVID-19 infections,” said Lori Daniels, M.D., M.A.S., lead author of the study, professor and director of the Cardiovascular Intensive Care Unit at UC San Diego Health. “We found that not only are statins and anti-hypertensive medications safe – they may very well be protective in patients hospitalized for COVID, especially among those with a history of hypertension or cardiovascular disease.”

This research sought to understand the relations between prior medication exposure, existing health conditions and COVID-19 outcomes using data from the American Heart Association’s COVID-19 Cardiovascular Disease Registry. The COVID-19 CVD Registry, powered by the American Heart Association’s Get With The Guidelines® platform, contains de-identified health data on patients treated for COVID-19 at over 140 participating hospitals across the country. As of July 2021, data from more than 49,000 patient records had been contributed into the platform.

“There is much to be learned about the impacts COVID-19 has on the heart and our cardiovascular system,” said Sandeep R. Das, M.D., MPH, MBA, FACC, FAHA, American Heart Association volunteer expert, COVID-19 CVD Registry committee co-chair and director for quality and value, cardiology division for UT Southwestern Medical Center. “Research like this is encouraging and has the potential to accelerate treatment patterns as we continue to examine best practices and novel pathways that improve patient outcomes.”

i>Source: American Heart Association

5-Minute Daily Breathing Exercise May Equal Meds in Lowering Blood Pressure

Amy Norton wrote . . . . . . . . .

A quick daily “workout” for the breathing muscles may help people lower their blood pressure to a similar degree as exercise or even medication, a small study suggests.

The technique is called inspiratory muscle strength training (IMST), and it involves using a device that provides resistance as the user inhales — essentially working out the diaphragm and other breathing muscles.

Researchers found that over six weeks, the exercises lowered study participants’ blood pressure by nine points, on average.

And all it took was five minutes of training per day, said lead researcher Daniel Craighead, an assistant research professor at the University of Colorado, Boulder.

There are caveats, he said: Study participants had higher-than-normal blood pressure but were healthy. It’s unclear how well the technique would work for people in poorer health.

There’s also the question of how long the benefits last, Craighead said, though this study turned up some encouraging results. Even after the training ended, most of the blood pressure reductions were sustained for another six weeks.

That hints there is “something special” about the breathing exercises, according to Craighead. “We’re excited to study it further,” he added.

The findings were recently published online in the Journal of the American Heart Association.

Inspiratory muscle strength training has been studied for lung conditions like asthma and emphysema and for boosting athletic endurance, according to Craighead, who uses the technique in his own marathon training.

But a recent trial found that for people with sleep apnea — a nighttime breathing disorder — IMST also lowered blood pressure.

So Craighead’s team wanted to see whether the training could help people whose only health issue was elevated blood pressure.

The study — which was funded by the U.S. National Institutes of Health and the American Heart Association (AHA) — involved 36 adults aged 50 to 79. All had above-normal systolic blood pressure (higher than 120 mm Hg). Systolic pressure is the force your blood exerts against artery walls when your heart beats.

The researchers randomly assigned participants to one of two groups: In one, participants used a hand-held device that provides resistance during inhalation — similar to trying to suck through a tube that sucks back.

The other group performed a “sham” version of the exercise, using a device that provided little resistance.

“It’s not relaxing, like slow deep breathing,” Craighead said of the real training. “It’s more like exercise.”

Luckily, it’s a brief workout — 30 inhalations, or about 5 minutes, per day.

After six weeks, the study found, people in the IMST group saw their systolic blood pressure drop from an average of 135 mm Hg to 126 mm Hg.

The improvement is on par with medication, according to Craighead, and even better than what’s typical with exercise.

No one, however, is saying that people should dump their current prescriptions and buy an IMST device.

It “would not be wise” to simply stop taking blood pressure medications or exercising, said Dr. Karen Griffin, chairwoman of the AHA’s hypertension council.

She said the findings raise the possibility that IMST could bring added benefits, and even allow some people to take less medication. But Griffin agreed that further study is needed to see whether the exercises are as helpful for people with co-existing conditions like heart disease and diabetes.

As for why IMST helps lower blood pressure, it’s not yet clear, Craighead said.

But study participants in the IMST group showed certain measurable changes: an increase in nitric oxide, a chemical that helps dilate arteries, plus a decrease in C-reactive protein, a marker of inflammation in the blood vessels.

People interested in trying IMST for their high blood pressure should talk to their doctor first, according to Griffin.

“It’s always prudent to check with your physician,” she said, “although I suspect most healthy individuals would be able to add this to their daily routine without any significant health risk.”

Craighead said he does not necessarily see IMST as a replacement for whole-body exercise.

“If you can exercise, do it,” he said. “Exercise has many benefits other than blood pressure control.”

But, he added, IMST might be particularly helpful for people who can’t exercise because of health problems or injuries, or who lack safe places for exercise.

The devices do require a financial investment: The product used in this study, the POWERbreathe K3 trainer, costs about US$430, according to the manufacturer’s website.

Source: HealthDay