Home blood pressure monitors can help people keep their blood pressure in check and possibly cut down on medication -- as long as the patients and their doctors put those home readings to good use, a new research review finds.
The analysis, of 37 international clinical trials, found that on average, adults with high blood pressure who were assigned to use home monitors shaved a few points off their blood pressure compared with counterparts who stuck with doctor's office measurements alone.
The home monitor users were also twice as likely to reduce the number of blood pressure medications they needed.
Researchers say the findings, reported in the journal Hypertension, should encourage people with high blood pressure to invest in a home monitor. The devices generally range in cost from about $25 to more than $100, depending on the features.
"Everyone who wants to know how well (their) blood pressure is controlled should monitor blood pressure at home," the study's lead author, Dr. Rajiv Agarwal of the Indiana University School of Medicine in Indianapolis, said.
He also likened blood pressure monitors to exercise treadmills, though. People may buy them with good intentions, but how they use them is what matters.
In their study, Agarwal and his colleagues found that home monitoring tended to work better when it was part of a general plan to adjust medications in response to the home readings.
The conventional way to do that is to bring your blood pressure readings to your doctor at each visit; some home monitors have memory storage that automatically records each reading and allows you to print out the information.
A few of the studies Agarwal's team reviewed tested so-called telemonitoring, in which wired or wireless technology is used to automatically send blood pressure readings to the doctor's office. Those studies tended to show greater effects on blood-pressure control than studies without telemonitoring.
Right now, though, telemonitoring is not commonly used for managing high blood pressure and studies are still investigating its value.
The findings are based on 37 clinical trials that included a total of 9,446 men and women with high blood pressure. In each, researchers randomly assigned some patients to use home blood pressure monitors and the rest to stay with office-based measurements. Most of the studies followed the participants for a few months to one year.
Overall, study participants using home monitors saw their blood pressure dip by 2 to 3 points, and most of the studies came out in favor of home monitoring over office-based measurements alone -- though the differences were generally small.
Patients with home monitors were also more likely to be able to cut down their drug regimen. In one of the larger trials, for example, 51 of 203 home-monitor patients reduced their number of medications, versus 22 of 197 patients without home monitors.
That, according to Agarwal's team, may be because home monitoring helps detect the "white coat effect" -- when a person's blood pressure spikes in the doctor's office.
Dr. Giuseppe Mancia, who co-wrote an editorial published with the study, agreed that home monitors are a good investment.
"I definitely believe that all (high blood pressure) patients should be advised by their physician to use a home BP monitor," Mancia, of the University of Milano-Bicocca in Italy, said.
He also pointed out, however, that patients should use the monitors only as often as their doctors recommend, and not become obsessive about checking their numbers. Obsessive checking could just spur anxiety, which could, in turn, boost blood pressure.
Mancia said people should also be sure to choose monitors that have been validated for accuracy according to international criteria. Certain professional groups, like the British Hypertension Society and the Association for the Advancement of Medical Instrumentation, test blood pressure monitors' reliability and maintain lists of validated monitors on their websites.
A blog about everything blood pressure and hypertension related brought to you by Experts in Blood Pressure
Wednesday, 15 December 2010
Wednesday, 17 November 2010
A short blast of radio waves to the kidneys can help control high blood pressure in patients who do not respond to medication, a study shows
The pioneering work, described in The Lancet medical journal, selectively severs nerves to the kidney that play a key role in regulating blood pressure. Although still in the testing phase, experts say the procedure could one day help hundreds of thousands of patients.
Half of patients fail to achieve good blood pressure control with drugs. This is partly because it can be difficult to remember to take medication every day. But for up to a fifth of patients it is because the drugs simply have no effect.
High blood pressure is an exceedingly common condition, affecting around one in three adults in England
To get to the kidneys, the doctors use a long, thin piece of tubing called a catheter that is threaded into an artery in the groin and guided up to the kidney. Once in place, the catheter is connected to a machine that generates radio waves, known as radiofrequency energy.
In this way, a short burst from the machine can knock out a number of tiny nerves that run in the lining of the arteries of the kidney. By stopping these nerves from sending signals the treatment lowers blood pressure. The Australian team, working with 24 centres across the globe, have tested the treatment in trials involving more than 100 patients. They found the therapy lowered blood pressure by about 10mmHg or more - which although is not enough to return blood pressure to a 'normal' level is enough to reduce some of the associated health risks of very high blood pressure. And, importantly, there were few side effects if any.
The first patient in the UK
"Further studies are needed to see if this invasive procedure will be acceptable to patients and produce long-lasting effects that are safe and reduce future cardiovascular events."
Source: BBC News
Garlic extract can reduce blood pressure say Australian researchers
Australian doctors enrolled 50 patients in a trial to see if garlic supplements could help those whose blood pressure was high, despite medication. Those given four capsules of garlic extract a day had lower blood pressure than those on placebo, they report in a scientific journal. Garlic supplements have previously been shown to lower cholesterol and reduce high blood pressure in those with untreated hypertension.
In the latest study, researchers from the University of Adelaide, Australia, looked at the effects of four capsules a day of a supplement known as aged garlic for 12 weeks. They found systolic blood pressure was around 10mmHg lower in the group given garlic compared with those given a placebo. Researcher Karin Ried said: "Garlic supplements have been associated with a blood pressure lowering effect of clinical significance in patients with untreated hypertension.
"Our trial, however, is the first to assess the effect, tolerability and acceptability of aged garlic extract as an additional treatment to existing antihypertensive medication in patients with treated, but uncontrolled, hypertension."
Experts say garlic supplements should only be used after seeking medical advice, as garlic can thin the blood or interact with some medicines.
Ellen Mason, senior cardiac nurse at the British Heart Foundation, said using garlic for medicinal purposes dates back thousands of years, but it is essential that scientific research proves that garlic can help conditions such as raised blood pressure. She said: "This study demonstrated a slight blood pressure reduction after using aged garlic supplements but it's not significant enough or in a large enough group of people to currently recommend it instead of medication.
"It's a concern that so many people in the UK
The study is reported in the journal Maturitas.
Source: BBC News
Tuesday, 16 November 2010
Teens warned to cut down salt if they wish to avoid high blood pressure
A teenager who consumes recommended quantities of salt each day has a considerably lower risk of developing hypertension (high blood pressure), stroke, heart disease, and dying prematurely later on in life during adulthood, researchers from the University of California, San Francisco, explained at the American Heart Association's Scientific Sessions 2010, Chicago. They added that processed foods contribute significantly to the high salt intake that currently affects many teens and their families. They also suggest that food manufacturers should do more to reduce the levels of salt in their produce.
Kirsten Bibbins-Domingo, Ph.D., M.D. and team used an advanced computer modeling analysis system to work out the long-term health benefits if salt levels in processed foods were reduced by 3-grams per day nationwide. They focused on produce consumed most commonly by male and female teenagers.
The team explain that teenagers consume more salt than any other age group inAmerica
They worked out that a 3 gram drop in daily salt intake among teenagers would result in a 380,000 to 550,000 reduction in the eventual number of young adults or late teenagers with hypertension (high blood pressure) - a decrease of between 44% to 63%.
This same reduction in daily salt intake during teen years would eventually result in between 2.7 million to 3.9 million fewer adults aged 35 to 50 with hypertension.
Bibbins-Domingo, Ph.D., M.D. said:
Kirsten Bibbins-Domingo, Ph.D., M.D. and team used an advanced computer modeling analysis system to work out the long-term health benefits if salt levels in processed foods were reduced by 3-grams per day nationwide. They focused on produce consumed most commonly by male and female teenagers.
The team explain that teenagers consume more salt than any other age group in
They worked out that a 3 gram drop in daily salt intake among teenagers would result in a 380,000 to 550,000 reduction in the eventual number of young adults or late teenagers with hypertension (high blood pressure) - a decrease of between 44% to 63%.
This same reduction in daily salt intake during teen years would eventually result in between 2.7 million to 3.9 million fewer adults aged 35 to 50 with hypertension.
Bibbins-Domingo, Ph.D., M.D. said:
"Reducing the amount of salt that is already added to the food that we eat could mean that teenagers live many more years free of hypertension. The additional benefit of lowering salt consumption early is that we can hopefully change the expectations of how food should taste, ideally to something slightly less salty.
A one-gram-per-day reduction in salt consumption results in a small drop of systolic blood pressure of 0.8 mm Hg. Reducing the salt in the teenage diet from an average of 9 grams to 6 grams would get teenage boys and girls to appropriate levels of salt intake."
A one-gram-per-day reduction in salt consumption results in a small drop of systolic blood pressure of 0.8 mm Hg. Reducing the salt in the teenage diet from an average of 9 grams to 6 grams would get teenage boys and girls to appropriate levels of salt intake."
Highlighted below are some projections the team made if teenagers reduced their daily salt intake. By the time the teenagers were 50 years old:
- There would be 120,000 to 210,000 fewer cases of coronary heart disease, a drop of 7% to 12%
- There would be 36,000 to 64,000 fewer heart attacks, a fall of 8% to 14%
- There would be 16,000 to 28,000 fewer strokes, a reduction of 5% to 8%
- There would be 69,000 to 120,000 fewer deaths from any cause
According to the researchers, approximately 80% of a typical teenager's salt intake comes from processed foods, just over a third comes from breads, pastries and cereals.
Bibbins-Domingo, Ph.D., M.D. said:
Bibbins-Domingo, Ph.D., M.D. said:
"The hidden places of salt in our diet are in breads and cereals, canned foods and condiments, and of course fast foods," said Bibbins-Domingo, also co-director of the UCSF Center
According to the National Center
The team welcomes the efforts made by some food manufacturers to reduce salt content in their produce, such as joining the National Sodium Reduction initiative. However, these efforts should be widened to all manufacturers, who should work with state and federal authorities.
Source: American Heart Association's Scientific Sessions 2010
Written by Christian Nrodqvist
Copyright: Medical News Today
The team welcomes the efforts made by some food manufacturers to reduce salt content in their produce, such as joining the National Sodium Reduction initiative. However, these efforts should be widened to all manufacturers, who should work with state and federal authorities.
Source: American Heart Association's Scientific Sessions 2010
Written by Christian Nrodqvist
Copyright: Medical News Today
Thursday, 11 November 2010
Solar powered BP monitor could be breakthrough for low-income nations health
Field tests at three medical centers in Africa -- two in Uganda and one in Zambia -- showed that the $32 automated device is 94 percent in agreement with the standard blood-pressure testing method for systolic blood pressure, which is the top number in a blood-pressure reading and represents the maximum pressure when the heart contracts.
It was less accurate for diastolic blood pressure (the lower number that shows pressure when the heart is relaxed), but that is something that should be easy to fix, the researchers said. They also noted that systolic blood pressure is the major contributor to cardiovascular events and tends to be the more important reading.
The research is reported Nov. 8 in the journal Hypertension.
It took about 15 minutes to train medical center staff to use the device. The staff then used the new device and a standard device to take blood pressure readings on about 716 patients. They repeated this one month later. Medical staff and patients said they preferred the solar device over the standard device.
"Solar energy eliminates the need for expensive rechargeable batteries in remote areas where electricity and the availability of batteries might be scarce, but sunlight is plentiful. It can be run on batteries, but it can also be left in the sunlight to charge, making it ideal for rural areas and use out in the bush," lead author Dr. Eoin O'Brien, a professor at Conway Institute of Biomolecular and Biomedical Research of the University College Dublin, Ireland, said in an American Heart Association news release.
He noted that the incidence of hypertension, or high blood pressure, has risen dramatically in low-income nations, many of which lack trained medical personnel.
"Hypertension leads to stroke and heart attack as the major cause of death around the world. It is greater than malnutrition, cancer and AIDS," O'Brien said.
"We have been able to provide an accurate, robust and inexpensive device to diagnose high blood pressure," O'Brien added. "It's a start. If we can't measure blood pressure, we certainly can't begin to treat hypertension."
SOURCE: American Heart Association, news release, Nov. 8, 2010 / HealthDay.
Researchers discover important link between adrenal gland hormone and brain in hypertension
Researchers at UT Southwestern Medical Center studied patients who overproduce aldosterone to see whether the hormone had any effect on sympathetic nerve activity responsible for blood pressure increases. "Between 10 percent and 20 percent of patients with high blood pressure who are resistant to treatment have elevated aldosterone hormones," said Dr. Wanpen Vongpatanasin, associate professor of internal medicine at UT Southwestern and senior author of the study in the October issue of the Journal of Clinical Endocrinology & Metabolism. "Previous studies in animals showed that this hormone can affect many parts of the brain that control the cardiovascular system. We wanted to understand whether aldosterone also increases the nerve activity that causes constriction of blood vessels, which elevates blood pressure in humans. "Since aldosterone can cause high blood pressure by affecting multiple systems and not just the kidneys, this study sheds light on why blood pressure is so difficult to control in patients with high aldosterone levels."
Aldosterone is an essential hormone that regulates electrolytes in the body. Created by the adrenal glands, it is responsible for re-absorption of sodium and water into the bloodstream and for regulating potassium. High levels of aldosterone can cause high blood pressure, muscle cramps and weakness.
Dr. Vongpatanasin and her team studied 14 hypertensive patients who overproduced aldosterone, a condition known as primary aldosteronism, and compared them with 20 hypertensive patients and 18 patients with normal blood pressure.
The data showed that in humans, aldosterone does increase activity in a part of the nervous system that raises blood pressure. Such activity contributes to the onset of hypertension. Furthermore, when the nerve activity was measured in patients who had adrenal surgery to remove tumors that produced this hormone, both nerve activity and blood pressure decreased substantially. "Our study also suggested that treatment of hypertension in these patients not only requires targeting the kidneys but also the sympathetic nervous system that controls blood pressure," Dr. Vongpatanasin said. "Since our study shows that patients with high aldosterone levels have high nerve activity, future studies are needed to determine how we could prevent effects of aldosterone on the brain."
The research was supported by the National Institutes of Health, the Donald W. Reynolds Foundation, the George M. O'Brien Kidney Research Center, the Lincy Foundation and the Burroughs Wellcome Fund.
Other UT Southwestern researchers who contributed to the study included senior author Dr. Andrew Kontak, postdoctoral researcher in internal medicine; Dr. Zhongyun Wang, research associate in internal medicine; Debbie Arbique, advance practice nurse in internal medicine; Beverley Adams-Huet, assistant professor of clinical sciences; Dr. Richard Auchus, professor of internal medicine; and Dr. Shawna Nesbitt, associate professor of internal medicine. Other researchers included Dr. Ronald Victor of Cedars-Sinai Medical Center.
Aldosterone is an essential hormone that regulates electrolytes in the body. Created by the adrenal glands, it is responsible for re-absorption of sodium and water into the bloodstream and for regulating potassium. High levels of aldosterone can cause high blood pressure, muscle cramps and weakness.
Dr. Vongpatanasin and her team studied 14 hypertensive patients who overproduced aldosterone, a condition known as primary aldosteronism, and compared them with 20 hypertensive patients and 18 patients with normal blood pressure.
The data showed that in humans, aldosterone does increase activity in a part of the nervous system that raises blood pressure. Such activity contributes to the onset of hypertension. Furthermore, when the nerve activity was measured in patients who had adrenal surgery to remove tumors that produced this hormone, both nerve activity and blood pressure decreased substantially. "Our study also suggested that treatment of hypertension in these patients not only requires targeting the kidneys but also the sympathetic nervous system that controls blood pressure," Dr. Vongpatanasin said. "Since our study shows that patients with high aldosterone levels have high nerve activity, future studies are needed to determine how we could prevent effects of aldosterone on the brain."
The research was supported by the National Institutes of Health, the Donald W. Reynolds Foundation, the George M. O'Brien Kidney Research Center, the Lincy Foundation and the Burroughs Wellcome Fund.
Other UT Southwestern researchers who contributed to the study included senior author Dr. Andrew Kontak, postdoctoral researcher in internal medicine; Dr. Zhongyun Wang, research associate in internal medicine; Debbie Arbique, advance practice nurse in internal medicine; Beverley Adams-Huet, assistant professor of clinical sciences; Dr. Richard Auchus, professor of internal medicine; and Dr. Shawna Nesbitt, associate professor of internal medicine. Other researchers included Dr. Ronald Victor of Cedars-Sinai Medical Center.
This news release is available on: http://www.utsouthwestern.edu/home/news/index.html
Tuesday, 9 November 2010
Kitchen Table review - A&D UA-767Plus Blood Pressure Monitor
Welcome to the first of my Kitchen Table Reviews. I aim to give validated blood pressure monitors the once over and look at them in terms of value for money, bells and whistles and ease of use.
Manufacturer: A&D Medical
Model: UA-767Plus Automatic Blood Pressure Monitor
Features:
Open the box of the UA-767Plus and you will find a handy blue vinyl bag for storing your monitor. Undo the zip and you will find your monitor, batteries and your cuff. The standard A&D adult cuff measures 22-32cm which is fine for average people, however, those with larger upper arms might want to see if they can get the UA-767Plus with a large cuff. If you need to know what size cuff you need see our video on watchyourbp.co.uk.
The face of the UA-767Plus is clean and simple A large single button starts the monitor up and automatically inflates the cuff to begin your measurement.
The screen has big numbers on and both the systolic and diastolic blood pressure are clearly marked with the pulse beats per minute coming at the bottom of the screen. On the left hand side of the screen which has a battery indicator and the clever bits.
Bells and whistles?
First off, the IHB or irregular heart beat monitor. What is this useful for. Well, if you know you suffer from an irregular heart beat or atrial fibrillation, this may well be able to detect it, although it is important to remember that the monitor can only pick up an irregular heart beat if it happens while you are having your blood pressure measured. Not everyone has “regular” irregular heart beats so it may not pick it up. It is, however, useful if you have a family history of stroke or irregular heart beat. Atrial Fibrilation is a risk factor for stroke and it is important that it is detected – this monitor may help you do this.
The other clever bit is the WHO Classification Indicator. WHO? They are the World Health Organisation based in Switzerland and interested in the health of us all globally. The WHO have a clear classification system which enables you to place yourself within a spectrum from optimal (120/80mmHg or below) through pre-hypertensive, mild and moderate hypertension all the way to severe hypertension. This monitor does it for you with a colour coded strip alongside the screen which clearly marks where you are in the classification. Personally, I thought that this would be really useful for those doing occasional readings or who want to make sure that there blood pressure is staying where it should be.
Ease of use?
It is very easy to use. No need for an idiots guide as it is simply a matter of putting the cuff on properly, sitting down and pushing the single button. All the figures are very clear and it provides what you need.
Who is it suitable for?
Anyone really, but only if you are interested in basic blood pressure monitoring. It does not connect to a PC and has no memory outside of a last reading re-call. If you are looking for a straight out of the bag monitor which will give you accurate readings but little else (discounting the IHB indicator) this will probably work for you. If you are looking to buy a monitor for an elderly relative who has been told to keep an eye on their blood pressure - this will work as well.
Star quality
I will give this monitor 4 stars. It is very easy to use, is clinically validated and has a 5 year guarantee. It falls down a bit on the bells and whistles, but if you do not want a memory or one to attach to your PC - and many people do not - this is ideal.
Cost
The RRP of the UA-767Plus is around £70. Mine was supplied by Experts in Blood Pressure products and they are selling it for £40 - so really good value for a clinically validated monitor.
Clinical validation details
The monitor is on the British Hypertension Society list of validated monitors. It has a European protocol pass and the paper was published in 2004 in Blood Pressure Monitoring*
*Verdeccia, P, Angeli, F, Poeta, F, REboldi, GP, Borgioni, C, Pittavini, L, and Porcellati, C. Validation of the A&D UA-774 (UA-767Plus) device for self-measurement of blood pressure.
Blood Pressure Monitoring 2004, 9 (4): 225-229
 |
| What's in the box? |
Model: UA-767Plus Automatic Blood Pressure Monitor
Features:
- Irregular Heart Beat (IHB) monitor
- Blood pressure classification indicator
- Last reading recall
- Extra large 3-line display for an easier read
- One-touch management
- SlimFit comfortable cuff
Open the box of the UA-767Plus and you will find a handy blue vinyl bag for storing your monitor. Undo the zip and you will find your monitor, batteries and your cuff. The standard A&D adult cuff measures 22-32cm which is fine for average people, however, those with larger upper arms might want to see if they can get the UA-767Plus with a large cuff. If you need to know what size cuff you need see our video on watchyourbp.co.uk.
The face of the UA-767Plus is clean and simple A large single button starts the monitor up and automatically inflates the cuff to begin your measurement.
 |
My blood pressure (after medication) clearly shown with the WHO indicator on the left hand side. |
The screen has big numbers on and both the systolic and diastolic blood pressure are clearly marked with the pulse beats per minute coming at the bottom of the screen. On the left hand side of the screen which has a battery indicator and the clever bits.
Bells and whistles?
First off, the IHB or irregular heart beat monitor. What is this useful for. Well, if you know you suffer from an irregular heart beat or atrial fibrillation, this may well be able to detect it, although it is important to remember that the monitor can only pick up an irregular heart beat if it happens while you are having your blood pressure measured. Not everyone has “regular” irregular heart beats so it may not pick it up. It is, however, useful if you have a family history of stroke or irregular heart beat. Atrial Fibrilation is a risk factor for stroke and it is important that it is detected – this monitor may help you do this.
 |
| Simple but clear face |
Ease of use?
It is very easy to use. No need for an idiots guide as it is simply a matter of putting the cuff on properly, sitting down and pushing the single button. All the figures are very clear and it provides what you need.
Who is it suitable for?
Anyone really, but only if you are interested in basic blood pressure monitoring. It does not connect to a PC and has no memory outside of a last reading re-call. If you are looking for a straight out of the bag monitor which will give you accurate readings but little else (discounting the IHB indicator) this will probably work for you. If you are looking to buy a monitor for an elderly relative who has been told to keep an eye on their blood pressure - this will work as well.
Star quality
I will give this monitor 4 stars. It is very easy to use, is clinically validated and has a 5 year guarantee. It falls down a bit on the bells and whistles, but if you do not want a memory or one to attach to your PC - and many people do not - this is ideal.
Cost
The RRP of the UA-767Plus is around £70. Mine was supplied by Experts in Blood Pressure products and they are selling it for £40 - so really good value for a clinically validated monitor.
Clinical validation details
The monitor is on the British Hypertension Society list of validated monitors. It has a European protocol pass and the paper was published in 2004 in Blood Pressure Monitoring*
*Verdeccia, P, Angeli, F, Poeta, F, REboldi, GP, Borgioni, C, Pittavini, L, and Porcellati, C. Validation of the A&D UA-774 (UA-767Plus) device for self-measurement of blood pressure.
Blood Pressure Monitoring 2004, 9 (4): 225-229
Thursday, 30 September 2010
Pine bark extract doesn't help with high blood pressure
Add pine-bark extract to the list of dietary supplements that don't live up to their promises of improved health. A new study from the Stanford University School of Medicine shows that pine-bark extract had no effect in lowering blood pressure or reducing other risk factors for heart disease.
Senior author Randall Stafford, MD, PhD, said the findings are part of a growing body of evidence that antioxidant supplements don't improve heart function.
"While there's a good biological basis to presume that antioxidant supplements might have a beneficial effect on heart health, this study is another example that they don't," said Stafford, associate professor of medicine at the Stanford Prevention Research Center. "There's also a broader message that many dietary supplements don't have the data to back up their claims of providing health benefits."
The study, which will be published in the Sept. 27 issue of the Archives of Internal Medicine, is the largest randomized, placebo-controlled clinical trial to date examining the effects of pine-bark extract on blood pressure and other heart disease risks.
Pine-bark extract has been reputed to have beneficial properties because it is an antioxidant, meaning that it counters the effects of free radicals - oxygen molecules that can damage cells in the body. While some previous studies linked pine-bark extract to reductions in blood pressure, Stafford said most of those studies were "open-label" (meaning that participants knew they were taking the extract) and didn't have control groups of patients who were given placebos. In some cases, participants took the extract in conjunction with other medication, so it wasn't possible to determine the effects of the pine-bark extract alone.
For the Stanford study, the researchers recruited 130 overweight individuals who had blood pressure above an optimal level but were not taking medication for it. Stafford said the researchers felt these were the types of people who would be more likely to seek out dietary supplements as an alternative therapy.
The participants were randomly assigned to take either a Japanese-produced pine-bark extract or a placebo. The extract dosage was 200 mg per day, which researchers said was in the middle range of dosages used in previous studies.
Blood-pressure readings and blood samples of the participants were taken before the study began, at six weeks and then again at the end of the 12-week study period. Additionally, participants were monitored to ensure that their diets, medications and weight didn't change during the study.
In analyzing the results, the researchers found that the participants' blood pressure levels - as well as other risk factors for heart disease, including cholesterol, blood glucose, body weight and C-reactive protein levels - remained virtually the same in both groups throughout the study.
"We conducted additional analyses to see if there were subgroups of patients who might have received a benefit from the supplement, but none of them did," Stafford said.
The study did confirm that the pine-bark extract was safe for consumption even though it didn't improve heart health, but Stafford said many other dietary supplements haven't undergone the same rigorous safety testing. He pointed to a U.S. Food & Drug Administration decision in 2004 to ban over-the-counter sales of ephedra, an herbal supplement that contained amphetamine-like drugs, because it caused heart problems.
"Most consumers presume that the supplements on the market are safe, but there isn't rigorous information to back up those presumptions," said lead study author Rebecca Drieling, MPH, research director for the SPRC's Program on Prevention Outcomes and Practices. "That's because federal regulations treat dietary supplements more like food than like drugs. Also chemical composition varies among dietary supplements, making standardized testing difficult."
Other co-authors include associate professor of medicine Christopher Gardner, PhD, and data analyst David Ahn, PhD. The study was funded by Toyo Shinyaku Co. of Japan, which provided the pine-bark extract along with the placebo tablets. None of the researchers has financial or consulting ties to the supplement company.
Senior author Randall Stafford, MD, PhD, said the findings are part of a growing body of evidence that antioxidant supplements don't improve heart function.
"While there's a good biological basis to presume that antioxidant supplements might have a beneficial effect on heart health, this study is another example that they don't," said Stafford, associate professor of medicine at the Stanford Prevention Research Center. "There's also a broader message that many dietary supplements don't have the data to back up their claims of providing health benefits."
The study, which will be published in the Sept. 27 issue of the Archives of Internal Medicine, is the largest randomized, placebo-controlled clinical trial to date examining the effects of pine-bark extract on blood pressure and other heart disease risks.
Pine-bark extract has been reputed to have beneficial properties because it is an antioxidant, meaning that it counters the effects of free radicals - oxygen molecules that can damage cells in the body. While some previous studies linked pine-bark extract to reductions in blood pressure, Stafford said most of those studies were "open-label" (meaning that participants knew they were taking the extract) and didn't have control groups of patients who were given placebos. In some cases, participants took the extract in conjunction with other medication, so it wasn't possible to determine the effects of the pine-bark extract alone.
For the Stanford study, the researchers recruited 130 overweight individuals who had blood pressure above an optimal level but were not taking medication for it. Stafford said the researchers felt these were the types of people who would be more likely to seek out dietary supplements as an alternative therapy.
The participants were randomly assigned to take either a Japanese-produced pine-bark extract or a placebo. The extract dosage was 200 mg per day, which researchers said was in the middle range of dosages used in previous studies.
Blood-pressure readings and blood samples of the participants were taken before the study began, at six weeks and then again at the end of the 12-week study period. Additionally, participants were monitored to ensure that their diets, medications and weight didn't change during the study.
In analyzing the results, the researchers found that the participants' blood pressure levels - as well as other risk factors for heart disease, including cholesterol, blood glucose, body weight and C-reactive protein levels - remained virtually the same in both groups throughout the study.
"We conducted additional analyses to see if there were subgroups of patients who might have received a benefit from the supplement, but none of them did," Stafford said.
The study did confirm that the pine-bark extract was safe for consumption even though it didn't improve heart health, but Stafford said many other dietary supplements haven't undergone the same rigorous safety testing. He pointed to a U.S. Food & Drug Administration decision in 2004 to ban over-the-counter sales of ephedra, an herbal supplement that contained amphetamine-like drugs, because it caused heart problems.
"Most consumers presume that the supplements on the market are safe, but there isn't rigorous information to back up those presumptions," said lead study author Rebecca Drieling, MPH, research director for the SPRC's Program on Prevention Outcomes and Practices. "That's because federal regulations treat dietary supplements more like food than like drugs. Also chemical composition varies among dietary supplements, making standardized testing difficult."
Other co-authors include associate professor of medicine Christopher Gardner, PhD, and data analyst David Ahn, PhD. The study was funded by Toyo Shinyaku Co. of Japan, which provided the pine-bark extract along with the placebo tablets. None of the researchers has financial or consulting ties to the supplement company.
Source: Medical News Today
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