Calcium channel blockers may cause hypotension if taken with some antibiotics

Older people who are taking common blood pressure medications called calcium channel blockers face an increased risk of developing dangerously low blood pressure and possibly going into shock if they take certain antibiotics, Canadian researchers warn. "Two common antibiotics, erythromycin and clarithromycin, if given to patients taking calcium channel blockers, can increase the risk substantially of being hospitalized for low blood pressure," said lead researcher Dr. David Juurlink, a scientist at Sunnybrook Research Institute in Toronto. For patients taking erythromycin along with a calcium channel blocker the risk goes up almost sixfold, while it increases almost fourfold for patients taking clarithromycin, he said.

Although the interaction between these drugs has been known for some 20 years, this is the first time the risk has been quantified, Juurlink said. Juurlink noted a cousin of these drugs, azithromycin, doesn't cause this problem. "One of the main suggestions of the study is, if you are on a calcium channel blocker and you need to go on an antibiotic in this class, azithromycin is a safer one to use," he said. The report is published in the Jan. 17 edition of the Canadian Medical Association Journal. For the study, Juurlink's team collected data on people aged 66 and older who were taking calcium channel blockers between 1994 and 2009.

The researchers sorted out who among these patients was hospitalized for low blood pressure (hypotension) and whether or not they had taken a macrolide antibiotic before being hospitalized. Juurlink's group found that 7,100 of these patients had been hospitalized for low blood pressure or shock, and that having taken either erythromycin or clarithromycin was associated with an increased risk of trouble. The reason these antibiotics have this effect is that they interfere with an enzyme in the liver that is needed to break down the calcium channel blocker. When this enzyme is "turned off," too much of the calcium blocker accumulates and causes blood pressure to drop dangerously low, Juurlink explained.

Dr. Barry J. Materson, a professor of medicine at the University of Miami Miller School of Medicine and a specialist in blood pressure, said that this study "is of practical interest." The researchers have established that the combination of a macrolide antibiotic and a calcium channel blocker can cause hypotension or even shock because of increased blood levels of the calcium channel blocker, Materson said. "This happens because of the interference with an enzyme that metabolizes the calcium blocker," Materson noted. Materson added that grapefruit juice can also interfere with the same enzyme and lead to elevated levels of calcium channel blockers. "Grapefruit juice is consumed much more frequently than macrolide antimicrobials," he pointed out.

One limitation of the study is not knowing how many of these patients had hypotension or shock from the infection for which they were receiving the antibiotic. "We also do not know how many, if any, consume grapefruit juice," Materson said. "Nevertheless, it is important for practitioners, pharmacists and patients to appreciate that both grapefruit juice and macrolide antibiotics, with the possible exception of azithromycin, can increase the blood level of the calcium channel blockers to an unpredictable degree and may rarely result in hypotension or even shock," he said.

Source: (HealthDay News)

Blueberries good for high blood pressure

Harvard researchers and scientists from University of East Anglia say blueberries protect from high blood pressure. The findings that the blueberries can stave off hypertension come from anthocyanins. In the study, researchers found eating one serving of the berries per day lowered their chances of developing high blood pressure 10 percent. Anthocyanins are members of the flavonoid family that are found in fruits, vegetables, grains and herbs. They are also present in high amounts in blackcurrants, raspberries, strawberries, aubergines, orange juice and blood oranges. The researchers studied blueberries because they are especially rich in the flavonoid that has antioxidant properties and commonly consumed in the U.S. Together the researchers studied 134,000 women and 47,000 men from the Harvard established cohorts, the Nurses' Health Study and the Health Professionals Follow-up Study over a 14 year span. The participant's health was assessed every 2 years via questionnaire and diet reviewed every 4 years.

The overall findings showed lower risk of high blood pressure from eating foods with anthocyanins, the bioactive component found in blueberries. Other foods considered high in flavonoids included tea - a main contributor - strawberries, apples, orange juice, blueberries, red wine, and strawberries. During the study, 35,000 participants developed high blood pressure. None had hypertension at the study start. The findings showed those consuming the highest amounts of flavonoids that came mostly from strawberries and blueberries in the US had an 8 percent reduced risk of hypertension. Blueberries offered stronger protection than strawberries.

Professor Aedin Cassidy of the Department of Nutrition at UEA's Medical School says, "Anthocyanins are readily incorporated into the diet as they are present in many commonly consumed foods. Blueberries were the richest source in this particular study as they are frequently consumed in the US. Other rich sources of anthocyanins in the UK include blackcurrants, blood oranges, aubergines and raspberries." The researchers are taking things further to study individual foods containing anthocyanins. The intention is to discover optimal dosing of foods like blueberries, strawberries and raspberries that can guide public health recommendations.

The findings show berries, especially blueberries, and other fruits contain beneficial compounds that can keep high blood pressure at bay. Cost of hypertension in the US is currently estimated at $300 billion annually and affects 25 percent of the global population, according to background information from the authors.

Worried about the housework? Stop – it’s bad for your blood pressure

If you have a very busy household regime that keeps you too much engaged in the jobs, you may fall victim to the problem of having a high blood pressure. In a recent study by the scientists from the University Of Pittsburgh School Of Medicine in the US, it suggests that stresses and strains of life remains alive even after the work hours of the day and it rises when one reaches home. The group conducted a research on 113 men and women, who work full time and at the same time maintain household chores to come to the conclusion.

The report of the study was published in the journal Psychosomatic Medicine. Each of the participants gave the details of their daily working hours, levels of responsibility they took for running their home, and the works specifically they did during these working hours. The observation period was for 3 weeks during which these women went for a regular BP checks in the local clinics and finally they were given a BP monitor to wear for a day to track the changes in the BP at different times of the day.

The results revealed that all those men and women who felt that they have more responsibilities to shoulder were at a greater risk of having a high BP. The researchers said, 'The perceived responsibility for household tasks, rather than the time spent doing those tasks, is what's most distressing."

Combination pills improve blood pressure management and outcomes

A combination of drugs is better than a single one in treating high blood pressure, a UK study has suggested. The study in the Lancet involved 1,200 people and found starting treatment with two drugs gave better and faster results, with fewer side effects. The approach challenges conventional medical practice where doctors give a patient one drug, then add another later if blood pressure stays high.

A team led by researchers at the University of Cambridge, University of Glasgow and University of Dundee followed 1,254 patients with high blood pressure in 10 countries. They compared the effects of giving one drug (either aliskiren or amlodipine) or a combination of both. Patients given the combination of drugs had a 25% better response during the first six months compared with those on conventional treatment, the study found. This equates to a 6.5mm Hg greater reduction in systolic blood pressure. Participants were also less likely to stop taking their medication due to side effects. The two drugs can be given as a single pill, making it easier for patients to take.

Professor Morris Brown of the University of Cambridge said the study "breaks the mould for treating hypertension". He said: "Most patients can now be prescribed a single combination pill and know that they are optimally protected from strokes and heart attacks."

The British Heart Foundation, which is funding follow-up research, said good control of blood pressure is hard to achieve in many patients.

Associate medical director Professor Jeremy Pearson said: "This study adds significantly to the evidence that starting treatment for patients with high blood pressure with two medicines rather than one is safe, and more effective than waiting to add the second medicine later."

The research was funded by the pharmaceutical company Novartis, which makes amlodipine and aliskiren.

Source: BBC News

Parents smoking can cause high blood pressure in children

Parents who smoke around their preschool-aged children may increase their kids' risk of having higher blood pressure at that young age compared to children who have parents who do not smoke, according to research published in Circulation: Journal of the American Heart Association. The study, performed by German researchers from the University of Heidelberg in Germany, is the first to show that environmental nicotine exposure can increase the blood pressure of children as young as 4 and 5 years old. And researchers say smoke exposure is likely to have a similar effect on the blood pressure of children in the U.S.

The study included 4,236 preschool children, aged 4 to 7years old, from the Heidelberg Kindergarten Blood Pressure Project, who were examined from February 2007 to October 2008. Researchers gathered questionnaires from 4,185 parents on their smoking habits. Parents who smoked: 28.5% of fathers, 20.7% of mothers, and 11.9% for both parents.

Factors That Raise a Child's Blood Pressure

• Height, body mass index (BMI), sex, and prenatal risk factors affected children's blood pressure, according to the study. Obese children were almost twice as likely to have a high-normal or elevated systolic (the top number) blood pressure.
  

Children born preterm or with low birth weight had higher systolic blood pressure values than children born at term, and children whose mothers smoked during pregnancy had higher systolic blood pressure than those who were not exposed during pregnancy. The study confirms findings from previous studies that these factors independently are associated with higher blood pressure in early childhood.

However, the unique finding of this study was the new evidence that exposure to tobacco smoke from smoking parents may raise the blood pressure of kids as young as 4 and 5 years old. Kids exposed to nicotine and smoke at home had higher systolic and diastolic blood pressure than kids who were not exposed. Children whose parents smoked had a 21% greater chance of having systolic blood pressure in the top 15%, even after researchers adjusted for the other risk factors mentioned above.

"Smoking adds to other risk factors," Giacomo D. Simonetti, MD, says in a news release. "Average blood pressure increased in proportion to the cumulative number of risk factors present."

The Argument for Smoke-Free Environments

The study suggests that implementing smoke-free environments, especially at home, may be necessary to preserve heart health for not only adults, but also for children. Researchers found that mothers smoking had a larger effect on kids' blood pressure than fathers smoking. The difference may be that mothers were more likely to smoke at home while fathers smoked more while at work, researchers say.

"The prevention of adult diseases like stroke or heart attack begins during childhood," Simonetti says. "Removing any avoidable risk factors as soon as possible will help reduce the risk for heart disease later on and improve the long-term health of children."

 

Source: WebMD

One in five women feel their stress levels are out of control - what does this mean for their blood pressure?

About one in seven Britons feels under extreme stress, a survey suggests.  Experts say stress raises blood pressure, putting people at greater risk of stroke. A poor diet and lack of exercise also contribute to the chances of suffering a stroke.  Stroke is the third most common cause of death in England and Wales after heart disease and cancer, killing more than 67,000 people every year.

Almost one in five women and one in 10 men feel their stress levels are out of control, according to the poll of 2,000 people.  The survey, by the Stroke Association and the engineering company Siemens, found almost a fifth of people said they took no exercise.  A similar number said they exercised for 30 minutes once a week.

More than a quarter of people aged 45 to 54 said they never exercised, despite suffering the highest stress levels.  Almost half said they were under more than "moderate stress".

Overall, 40 per cent of those surveyed said they were unaware of the link between exercise and lowering the risk of stroke.  James Beeby, of the Stroke Association, said: "The research is incredibly worrying and emphasises the need for people to be aware of the dangers of stroke.  "It's imperative that people take regular exercise and modify their diet to reduce the risk of suffering a stroke."

 

Source: Daily Telegraph

Use your iPhone as a blood pressure monitor

Withings has launched a blood pressure monitor that works with a software app downloadable to the iPhone and iPod Touch.

In the words of the press release:

“With the Withings Blood Pressure monitor, measuring and understanding your blood pressure couldn't be easier. All data is recorded and saved to the user's secure online space for easy measurement access and retrieval through their iPhone, iPad or other screen connected to a user-friendly interface.”

Currently, the Withings Blood Pressure Monitor is available for 129 Euros which is quite a lot more expensive that high quality monitors already available on the market.  It is not clear whether the monitor has been clinically validated against existing standards.

Watch this space…