High Blood Pressure in 40s a Dementia Risk for Women

Dennis Thompson wrote . . . . . . .

Women who develop high blood pressure in their 40s could be much more vulnerable to dementia later in life, a new study suggests.

That increased risk could run as high as 73 percent, the researchers reported, but the same did not hold true for men.

These new findings suggest that high blood pressure can start playing a role in brain health even earlier than previously thought, said lead researcher Paola Gilsanz, a postdoctoral fellow with the Kaiser Permanente Northern California Division of Research in Oakland.

Prior studies have linked high blood pressure with dementia, but “it wasn’t clear if hypertension before one’s 50s was a risk factor,” Gilsanz said.

A healthy circulatory system is key to a health brain, said Keith Fargo, director of scientific programs and outreach for the Alzheimer’s Association.

“The brain is a very metabolically active organ in the body. It requires an outsized amount of oxygen and other nutrients,” said Fargo, who wasn’t involved with the study. “Because of that, there’s a very, very rich blood delivery system in the brain. Anything that happens to compromise that is going to compromise the overall health and function of the brain.”

Because of that, it stands to reason that long-term exposure to high blood pressure could leave one more vulnerable to dementia as they enter old age, Gilsanz said.

Gilsanz and her colleagues reviewed the records of more than 5,600 patients of the Kaiser Permanente Northern California health care system, tracking them from 1996 onward for an average 15 years to see who developed dementia.

They found that people with high blood pressure in their 30s did not appear to have any increased risk of dementia.

But women who developed high blood pressure in their 40s did have an increased risk of dementia, even after the researchers adjusted for other factors like smoking, diabetes and excess weight.

However, the study did not prove that early high blood pressure caused dementia risk to rise in women, just that there was an association.

Men did not have a similar risk from high blood pressure in their 40s, but that could be because they were more likely to die before they grew old enough to suffer from dementia, Gilsanz noted.

Other factors such as genetic differences, lifestyle differences and sex-specific hormones also might separate men and women when it comes to dementia risk associated with high blood pressure, Fargo said.

“It’s really interesting to see there was an association among women but not men,” Gilsanz said. “Given that women have higher rates of dementia than men, understanding why this may be is a large area of interest for us. Future research should really look at sex-specific pathways that might be at play, to disentangle the risk factors for men and women.”

Fargo said it makes sense that people with long-term exposure to high blood pressure would be more likely to develop dementia.

“Your dementia risk is really a lifelong thing,” Fargo said. “People think about dementia in late life, because that’s when it’s common to see the clinical symptoms. But everything that is setting you up for cognitive decline is occurring throughout your life.”

But Fargo sees this as an opportunity, given that high blood pressure can be controlled with medication and lifestyle changes.

“These modifiable risk factors are the most powerful weapons we have in our arsenal to fight dementia,” he said. “It’s a target that is addressable.”

The study was published in the journal Neurology.

Source: HealthDay


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Adverse Events Spike after Blood Pressure Medicines Go Generic in Canada

One month after generic versions of three widely-used blood pressure drugs became available in Canada, hospital visits for adverse events spiked in generic drug users, according to new research in Circulation: Cardiovascular Quality and Outcomes, an American Heart Association journal.

Researchers in Quebec compared hospital visits and emergency room consultations among 136,177 patients, aged 66 years and older, who took one of three hypertension medications before and after their generic versions became available. The drugs – losartan (Cozaar®), valsartan (Diovan®) and candesartan (Atacand®) – are also used in patients with heart failure.

They found:

  • Before generic versions were commercialized, the average proportion of adverse events was 10 percent.
  • The month when generics were commercialized, the rates of adverse events ranged from 8 percent to 14 percent for patients using generics, depending on the type of drug.
  • The increase was 8 percent for losartan, 11.7 percent for valsartan and 14 percent for candesartan, and the rates for losartan remained consistently higher for the study year.

“Because most users of a brand-name drug are switched to generic versions within two or three years after it becomes available, the observed increase in adverse events could reflect an acute response to equivalent, but not identical, generic drugs for newly switched patients,” said Paul Poirier M.D., Ph.D., FAHA, study author and professor of pharmacy at Laval University in Quebec City.

The immediate increase of adverse events in these three generic drugs could, hypothetically, be explained by differences between drugs. “In our study, patients could have been substituted to a generic version that is pharmacokinetically 6 to 21 percent different from the brand-name version that was used,” Poirer said. “The results must be interpreted cautiously because studies like this assessing adverse events over a fixed time period, combined with differences between patients, make drawing firm conclusions difficult. Also, because the findings were based on medical claims data, there may be inaccuracies.”

After the first month, the difference between brand names and generics narrowed, but some differences persisted – primarily cardiovascular problems, he said. To some degree the findings might partially reflect various demographic differences between generic users, although clinical differences among very sick and lower socioeconomic patients were minimal, according to the authors.

“Although generic drugs are generally considered to be equivalent, patients and their physicians should be aware that they may not have exactly the same effect as their brand-name counterparts, especially during the first month as patients transition to the new medicine,” Poirier said.

Source: American Heart Association


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Frequent Sauna Bathing Keeps Blood Pressure in Check

Frequent sauna bathing reduces the risk of elevated blood pressure, according to an extensive follow-up population-based study carried out at the University of Eastern Finland. The risk of developing elevated blood pressure was nearly 50% lower among men who had a sauna 4-7 times a week compared to men who had a sauna only once a week. These findings were published recently in the American Journal of Hypertension.

The same researchers have previously shown that frequent sauna bathing reduces the risk of sudden cardiac death, and cardiovascular and all-cause mortality. Elevated blood pressure is documented to be one of the most important risk factors of cardiovascular diseases. According to the research group, underlying protective mechanisms may include the beneficial effects of regular sauna bathing on blood pressure.

The Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD) involved 1,621 middle-aged men living in the eastern part of Finland. Study participants without elevated blood pressure of over 140/90 mmHg or with diagnosed hypertension at the study baseline were included in this long-term follow-up study. Based on their sauna bathing habits, men were divided into three sauna frequency groups: those taking a sauna once a week, 2-3 times a week, or 4-7 times a week. During an average follow-up of 22 years, 15.5% of the men developed clinically defined hypertension. The risk of hypertension was 24% decreased among men with a sauna frequency of 2-3 times a week, and 46% lowered among men who had a sauna 4-7 times a week.

Sauna bathing may decrease systemic blood pressure through different biological mechanisms. During sauna bathing, the body temperature may rise up to 2 °C degrees, causing vessels vasodilation. Regular sauna bathing improves endothelial function, i.e. the function of the inside layer of blood vessels, which has beneficial effects on systemic blood pressure. Sweating, in turn, removes fluid from the body, which is a contributing factor to decreased blood pressure levels. Additionally, sauna bathing may also lower systemic blood pressure due to overall relaxation of the body and mind.

A recent analysis of the same study also revealed that those taking a sauna frequently have a lower risk of pulmonary diseases.

Source: Science Daily


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High Blood Pressure Reasons Differ by Gender in Teens and Young Adults

There are marked gender differences in what drives blood pressure in middle-age in adulthood, suggesting the need for gender-specific treatments for high blood pressure, according to research presented today at the American Heart Association (AHA) Council on Hypertension, AHA Council on Kidney in Cardiovascular Disease, American Society of Hypertension Joint Scientific Sessions 2017, in San Francisco.

Background

“Blood pressure is determined mainly by three factors: heart rate; stroke volume, which is the volume of blood pumped by the heart; and the resistance to blood flow through the vessels, called total peripheral resistance. An increase in any one of the three factors can lead to an increase in blood pressure,” said study author Catriona Syme, Ph.D., postdoctoral fellow at The Hospital for Sick Children (SickKids) in Toronto, Ontario, Canada. “The key takeaway from this study is that, for young and middle-aged women, stroke volume was the main determinant of blood pressure, while, in men, vascular resistance was the main determinant of blood pressure.”

Syme and colleagues studied 1,347 Canadians from the Saguenay Youth Study, including 911 adolescents and 426 adults ages 36 to 65 years. The researchers used a device that measures beat-by-beat blood pressure and the underlying forces of heart rate, stroke volume and total peripheral resistance. In the approximately hour-long protocol, they measured these variables at rest, and during posture changes and a mental stressor – all designed to mimic daily life activities, according to Syme.

Researchers found:

  • In females, stroke volume explains 55 percent of the variance in systolic blood pressure (the top number in a blood pressure reading), versus only 35 percent in males.
  • In males, the major determinant of systolic blood pressure was total peripheral resistance, which explained 47 percent of the variance, versus only 30 percent in females.
  • These gender differences were seen across most of the 52-minute protocol, being most prominent during standing and least evident during mental stress, according to the abstract.

This study is novel in that it looks at the relative contributions of the three parameters determining blood pressure, which have not been evaluated in a large population-based study, and it assesses these factors over time, in a way that mimics daily life activities. The study also looks at high blood pressure culprits in adolescents and young to middle aged adults, who are not frequently studied despite being affected by hypertension, according to Syme.

“For example, there have been many studies looking at sex differences in the usefulness of blood pressure medications. But, most of those studies have been done in people whose average age was 60-70 years — many of the women being post-menopausal,” Syme said. “We think pre-menopausal women and men of a similar age may have elevated blood pressure for different reasons, and thus may need to be treated for hypertension differently. After menopause, when the production of female sex hormones decreases, reasons for hypertension may be more similar in men and women.”

While current treatment recommendations for hypertension do not differ by gender across all ages, this study suggests potential benefits to prescribing blood pressure-lowering medications with consideration for gender differences in the underlying physiology of elevated blood pressure in young and middle-aged adults.

This study was conducted in Caucasians. Future studies should investigate whether the relative contributions of these parameters differ by race.

Source: American Heart Association


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Researchers Advise Caution about Recent US Advice on Agressively Lowering Blood Pressure

Medical researchers at Trinity College Dublin, Ireland, are advising caution when treating blood pressure in some older people — after results from a study contrasted with recent advice from the US to attempt to aggressively lower blood pressure in all adults to targets of 120mmHg.

Researchers from the Irish Longitudinal Study on Ageing (TILDA) at Trinity College Dublin, in collaboration with Beaumont Hospital, Dublin, have recently published the findings in the Journal of the American Medical Association (JAMA Internal Medicine).

A large randomised blood pressure trial led by US investigators — the Systolic blood Pressure Intervention Trial (SPRINT) — demonstrated that lowering systolic blood pressure to levels of 120mmHg or less compared with 140mmHg or less in adults (over 50 years with cardiovascular risk) significantly reduced death (from all causes and from heart failure and heart attacks). The study also reported that common side effects of low blood pressure such as falls, injuries, blackouts, and drops in blood pressure after standing were not increased by aggressive treatment — even in people over 75 years old.

Because the latter findings were clinically counter intuitive, the TILDA team tested whether they held true outside of a trial setting. Focusing on people in Ireland over 75 years, they examined rates of falls, injuries, blackouts and excessive drops in standing blood pressure in those who met the criteria for the treatment proposed in SPRINT and were followed up with for 3½ years — the same time period as SPRINT.

The researchers reported starkly contrasting results — falls and blackouts were up to five times higher than reported in SPRINT and drops in blood pressure on standing were almost double that reported in SPRINT. Therefore, in people over 75 years, intensive lowering of blood pressure to 120mmHg could result in harm and TILDA researchers recommend that a better understanding of who, over 75 years, will or will not benefit, is necessary before widespread adaptation of the SPRINT results.

The TILDA team is now assessing how best to determine which people may benefit from SPRINT, and which people are more at risk from aggressive blood pressure lowering.

First author of the journal article, Research Fellow at TILDA, Dr Donal Sexton, said: “SPRINT was a landmark study of hypertension treatment. While the benefits of lowering blood pressure seen in this study are not in dispute, we are highlighting to physicians that we need to be cognisant of the fact that the trial was not powered for adverse events such as falls causing injury. Physicians ought not to expect a similarly low rate of adverse events in clinical practice as was observed in the trial when lowering blood pressure in older people. Overall what we are saying is that the risks and benefits of lowering blood pressure should be individualised for each patient. ”

Professor Rose Anne Kenny, founding Principal Investigator with TILDA and lead author of the journal article commented: “Our work and that of other groups has shown that low blood pressure and particularly drops in standing blood pressure are linked not only to falls, fractures and fall- and blackout-related injuries, but also to depression and possibly other brain health disorders.”

“These outcomes can seriously impact on independence and quality of life and we advise caution in applying the SPRINT recommendations to everyone over 75 years without detailed assessment of an individual’s risk versus possible benefit until such a time as we can provide more clarity re treatment.”

Source: Science Daily