Blood pressure changes at middle age raises risk for later heart attack or stroke
Posted by on December 30, 2011 - 6:22am

A hike in your blood pressure during middle age significantly raises the risk of having a heart attack or a stroke during your lifetime, according to new Northwestern Medicine research. The study offers a new understanding on the importance of maintaining low blood pressure early in middle age to prevent heart disease later in life.  Men and women who developed high blood pressure in middle age or who started out with high blood pressure had an estimated 30 percent increased risk of having a heart attack or stroke compared to those who kept their blood pressure low.

Previous estimates of a person’s risk of cardiovascular disease were based on a single blood pressure measurement. The higher the blood pressure reading, the greater the risk. The new Northwestern Medicine study expands on that by showing a more accurate predictor is a change in blood pressure from age 41 to 55.

“We found the longer we can prevent hypertension or postpone it, the lower the risk for cardiovascular disease,” said lead author Norrina Allen, assistant professor of preventive medicine at Northwestern University Feinberg School of Medicine. “Even for people with normal blood pressure, we want to make sure they keep it at that level, and it doesn’t start increasing over time.”

“There hasn’t been as much of a focus on keeping it low when people are in their 40’s and 50’s,” Allen added. “That’s before a lot of people start focusing on cardiovascular disease risk factors. We’ve shown it’s vital to start early.”  People that maintain or reduce their blood pressure to normal levels by age 55 have the lowest lifetime risk for a heart attack or a stroke.

The study used data from 61,585 participants in the Cardiovascular Lifetime Risk Pooling Project. Starting with baseline blood pressure readings at age 41, researchers measured blood pressure again at age 55, then followed the patients until the occurrence of a first heart attack or stroke, death or age 95.

The study did include men and women demonstrating a growing increase in important sex based medicine.   Men who developed high blood pressure in middle age or who started out with high blood pressure had a 70 percent risk of having a heart attack or stroke compared to a 41 percent risk for men who maintained low blood pressure or whose blood pressure decreased during the time period. Women who developed high blood pressure had almost a 50 percent risk of a heart attack or stroke compared to a 22 percent risk for those who kept their blood pressure low or saw a decrease.

Men generally have a 55 percent risk of cardiovascular disease in their lifetimes; women have a 40 percent risk.

“Our research suggests people can take preventive steps to keep their blood pressure low early on to reduce their chances of a heart attack or stroke,” said Donald M. Lloyd-Jones, MD, study co-author, chair of preventive medicine at Northwestern.  “Maintaining a healthy diet, combined with exercise and weight control, can help reduce blood pressure levels and, consequently, your risk for cardiovascular disease later in life.”

The study is published in Circulation: Journal of the American Heart Association

 

Women increase heart disease risk with sugary drinks more than men
Posted by on November 29, 2011 - 10:38am

Women who regularly drink sugary beverages may be increasing their cardiovascular risk, researchers found.  A longitudinal study showed that those who reported drinking at least two sugar-sweetened beverages every day were more likely to gain weight, increase waist size, and develop impaired glucose tolerance, according to Christina Shay, PhD, of the University of Oklahoma in Oklahoma City.

The same associations were not seen in men, which suggests that the factors responsible for the relationship between sugary drinks and cardiovascular disease differ between the sexes, Shay reported at the American Heart Association meeting recently held in Orlando.

"Women exhibit lower energy requirements overall and they may be at elevated risk for cardiovascular risk factors when a greater proportion of calories is consumed in the form of sugar-sweetened beverages," she said at a press briefing.  Sugar-sweetened beverages have been associated with a host of health problems, including weight gain, obesity, hyperglycemia, type 2 diabetes, and hypertension.

But few of the studies have examined the relationships in ethnically diverse populations, Shay said.So she and her colleagues turned to the Multi-Ethnic Study of Atherosclerosis (MESA), in which 38% of the participants were non-Hispanic white, 28% were black, 22% were Hispanic, and 12% were Chinese American.

All 4,166 men and women included in the current analysis were ages 45 to 84 and were free from cardiovascular disease and type 2 diabetes at baseline. They reported dietary habits on a food frequency questionnaire completed at baseline. Sugar-sweetened drinks included regular soft drinks, soda, sweetened non-diet mineral water, and nonalcoholic beer.  Overall, 8.4% of the participants reported drinking at least two sugary beverages each day.

Through about five years of follow-up, women with that level of consumption were more likely to have more than 3% increase in waist circumference (63.7% versus 54.1%), to have high triglycerides (24.3% versus 10%), and to have impaired fasting glucose (26.8% versus 20.4%) compared with women who drank less than one sugary beverage a day.

The differences remained significant after adjustment for several potential confounders, including both baseline weight and weight change throughout the study.   None of the associations was statistically significant for men.

Rachel Johnson, PhD, MPH, RN, of the University of Vermont, said that "based on these findings, women especially should choose their beverage calories carefully and stick primarily to water, unsweetened coffee and tea, other low calorie drinks, and non- or low-fat milk."

"This study reinforces the American Heart Association's message that a heart-healthy diet limits sugar-sweetened beverages to no more than 450 calories or 36 ounces per week," said Johnson, who is an AHA spokesperson.

Obesity projections worse than terrorism threat for future--and we can do something about it.
Posted by on November 25, 2011 - 8:18am

In 2020, the vast majority of adults in America will be overweight or obese and more than half will suffer from diabetes or pre-diabetic conditions, according to projections presented by Northwestern Medicine researchers at the American Heart Association (AHA) Scientific Sessions recently in Orlando.

The AHA has set a target to help Americans improve their overall heart health by 20 percent in 2020. However, if current trends continue, Americans can expect only a modest improvement of six percent in overall cardiovascular health in 2020.

The implications of not increasing heart health by 20 percent by 2020 are grave. Declining rates of sickness and death from cardiovascular disease may stall, and related health care costs, already projected to reach $1.1 trillion per year by 2030, could rise even further. That’s according to study author Mark Huffman, MD, assistant professor in preventive medicine and medicine-cardiology at Northwestern University Feinberg School of Medicine.

Representative of all Americans, the study is based on patterns found in the National Health and Nutrition Examination Surveys (NHANES) from 1988 to 2008. The projected numbers on weight and diabetes, based on previous trends, follow.

In 2020, 83 percent of men and 72 percent of women will be overweight or obese. Currently, 72 percent of men and 63 percent of women are overweight or obese (people who are overweight have a BMI of 25 to 29, people who are obese have a BMI of 30 or greater).   In 2020, 77 percent of men and 53 percent of women will have dysglycemia (either diabetes or pre-diabetes). Currently, 62 percent of men and 43 percent of women have dysglycemia.

“To increase overall heart health by 20 percent, American adults would need to rapidly reverse these unhealthy trends -- starting today,” Huffman said.More people would need to improve health behaviors related to diet, physical activity, body weight and smoking, and health factors, related to glucose, cholesterol and blood pressure.

"We’ve been dealing with the obesity trend for the past three decades, but the impact we project on blood sugar is a true shock,” said Donald Lloyd-Jones, MD, chair and associate professor of preventive medicine at Feinberg. “Those are some really scary numbers. When blood sugar goes up like that all of the complications of diabetes come into play."

Less than five percent of Americans currently are considered to have ideal cardiovascular health. The modest six percent improvement in cardiovascular health that is projected for 2020 means better cholesterol and blood pressure numbers for Americans and fewer smokers. Improvements in treatment and control of cholesterol and blood pressure with medication and declines in smoking would partially account for this small boost, but they wouldn’t be enough to offset the weight and diabetes problems Americans face, Huffman said. Projected improvements in diet and physical activity also contribute to the six percent projection, but the absolute increase in Americans who consume ideal diets will remain less than two percent by 2020, if current trends continue.

“Since the 1960s cardiovascular disease death rates have substantially decreased, but if the weight and dysglycemia trends continue to grow past 2020, we are in danger of seeing those overall numbers start to reverse,” Huffman said.Achieving a healthy weight through diet and physical activity is the best way most Americans can improve their cardiovascular health, but, as Huffman stressed, not smoking is the number one preventable cause of preventable death. Yet, one in five Americans still smoke.

Why research is sometimes trial and error: a case study
Posted by on November 9, 2011 - 9:58am

Consumers are often frustrated when they hear the results of research studies that indicate a "maybe" rather than a definitive answer.  Here's an interesting study that demonstrates the long road researchers often have to take.  On the other hand, trial and error sometimes leads to surprising results and are worth it.  This example also demonstrates how different medical disciplines can learn from each other.

A new study suggests that a common sexually transmitted virus already linked to cancer may also cause cardiovascular disease.

Women infected with the human papillomavirus, or HPV, are two to three times as likely as uninfected women to have had a heart attack or stroke, according to a report published recently in The Journal of the American College of Cardiology.

HPV is known to cause cancer of the cervix, vulva, penis, anus and throat, but the new study is the first to connect the virus to heart disease. The heart findings are not definitive: They show the virus may be associated with heart disease, but do not prove it caused the disease.

The senior author of the study, Dr. Kenichi Fujise, a cardiologist at the University of Texas Medical Branch in Galveston, said the research grew out of his quest to find out why some people have heart attacks even though they have none of the usual risk factors, like high cholesterol or high blood pressure. About 20 percent of patients with heart disease lack obvious risk factors, and researchers think those people must have other underlying problems that science has not yet figured out.

Dr. Fujise decided to study HPV because the virus can sabotage a gene called p53, which normally protects the body from cancer and may also help prevent artery disease. Inactivation of p53 occurs in a variety of cancers, and the gene is considered to be a sort of guardian of the genome. Disabling p53 may also lead to inflammation and thickening in the walls of arteries.  HPV is the most common sexually transmitted infection in the United States. Scientists estimate that half of sexually active men and women have been infected and that 80 percent of women have had it by age 50. The virus has many strains, only some of which cause cancer. In most people, the immune system fights off the virus.  The infection persists and causes cancer in only a small minority. Two vaccines are approved to prevent HPV infection and are recommended for young people before they become sexually active. The vaccine does not work in people who are already infected.

Dr. Fujise studied 2,450 women, ages 20 to 59, who took part in a national health survey from 2003 to 2006. The women used vaginal swabs to provide specimens for HPV testing and reported whether they had heart disease, which was defined in this study as ever having suffered a heart attack or stroke.

In all, 1,141 women had HPV. Sixty women had heart disease; of those, 39 also had HPV. When the researchers analyzed the data and adjusted for heart risks like smoking, blood pressure and weight, they found that women with HPV were 2.3 times as likely as those without the virus to have heart disease. The risk was even higher, 2.86 times that of uninfected women, in those who had HPV strains known to cause cancer.

Dr. Fujise said the results surprised him. “I was thinking maybe there would be just a weak link or no link, but this is a strong link,” he said.   Even if further research confirms the connection, most people who contract HPV would not be at special risk for heart disease. Dr. Fujise said that if the link is real, heart disease, like cancer, would be likely to develop only in people with lingering HPV infection.

A researcher not involved with the study, Dr. Lori Mosca, director of preventive cardiology at NewYork-Presbyterian Hospital/Columbia University Medical Center, said: “I’m definitely intrigued by this. The biological argument is highly plausible and deserves further investigation.”

But she emphasized that plausibility is not enough; the history of medicine is full of ideas that made sense and turned out to be wrong. The type of study that Dr. Fujise did, in which scientists look for associations in a mass of data, is good for generating ideas for more research, but it does not prove cause and effect.

Finding an association does not even tell which condition came first. In theory, heart disease could have come first and made the women more vulnerable to HPV. Or some other unknown factor could have predisposed some women to both HPV and heart disease.

“We need to proceed with caution,” Dr. Mosca said. “We need to go on and do more rigorous kinds of research that would answer the question more definitively.”She said that many researchers were studying possible links among cancer, infections and heart disease, but that so far no infection had been proved to cause artery disease.

Dr. Fujise’s work, she said, “has the potential, if it does pan out, to further inform the public about the potential benefits of vaccination for HPV.” But she added that the findings were too preliminary to be used as evidence in favor of vaccination.

Sex differences in heart disease
Posted by on November 5, 2011 - 7:07am

Heart disease affects men and women in different ways. In women, symptoms of burgeoning heart disease are often more insidious, but when a heart attack strikes, it is more lethal than it is in men. Roughly 25 percent of men will die within a year of their first heart attack, but among women, 38 percent will die. Women are twice as likely as men to have a second heart attack within 6 years of their first one, and women are twice as likely as men to die after bypass surgery.

Yet after a heart attack, women’s hearts are more likely to maintain their systolic function—their ability to contract and pump blood from the chambers into the arteries. According to C. Noel Bairey Merz, MD, Director of the Women’s Heart Center at Cedars-Sinai Heart Institute in Los Angeles, this suggests that heart disease manifests differently in women, affecting the microvasculature (small blood vessels) instead of the macrovasculature (major blood vessels) as it does in men.

The heart is a muscle, and as with other muscles, depriving it of oxygen causes damage that diminishes its ability to function. Conventional wisdom notes that the most prevalent form of heart disease is coronary artery disease, in which atherosclerotic plaque narrows and eventually blocks the major arteries leading into the heart, thus cutting off the heart’s supply of oxygen. The damage to the heart tends to be permanent, and after a heart attack, the heart never quite regains its former power.

But when reviewing the medical literature, Dr. Bairey Merz and her colleagues found that women’s hearts were less likely than men’s to lose their ability to pump blood after a heart attack, and that female heart patients were less likely to present with obstructive coronary artery disease. Instead, the oxygen deprivation and subsequent damage to the heart is more likely to occur when small blood vessels, not major arteries, become dysfunctional.

“That is the reason women are often misdiagnosed and suffer adverse events,” said Dr. Bairey Merz. “Physicians have been looking for male pattern disease, when we need to start looking at female patterns.” Likewise, more research is needed to develop appropriate treatments and reduce risk in women, she added.

According to Dr. Bairey Merz, the good news is that it is possible to measure damage to small blood vessels objectively. “The gold standard is reactivity testing, angiograms, and other physiologic measures, rather than anatomic study.”

Dr. Bairey Merz is looking at data that  can be applied to help clinicians understand gender differences in the pathophysiology of heart disease.

 

Smoking increases heart risk more in women than in men
Posted by on October 12, 2011 - 1:26pm

Smoking is definitely a risk factor for heart disease but until recently it was not known if this risk was higher in women.   Study results published in Lancet in August 2011 suggest that the risk of heart disease due to smoking is higher in women.

The large meta analysis suggested that the harmful effects of tobacco smoking affect men and women differently.  In a study of more than two million people, researchers showed that the pooled adjusted female-to-male relative risk of coronary heart disease in smokers vs nonsmokers is 25% higher in women. If anything, said Dr. Rachel Huxley from University of Minnesota, the 25% increased risk may be on the conservative side.  Women have not been smoking as long as men, so the true impact on women's health may not have manifested yet.

Of particular concern are the increasing number of young girls starting to smoke compared to young boys.   ALERT:   Young ladies who start smoking, you might think you look cool now but you won't look so cool when you get older and are walking around with an oxygen tank!

New research examines how estrogen could protect women from heart disease
Posted by on August 26, 2011 - 6:54am

The sex hormone estrogen could help protect women from cardiovascular disease by keeping the body's immune system in check, new research from Queen Mary, University of London has revealed.

The study has shown that the female sex hormone works on white blood cells to stop them from sticking to the insides of blood vessels, a process which can lead to dangerous blockages.

The results could help explain why cardiovascular disease rates tend to be higher in men and why they soar in women after the menopause.

The researchers compared white blood cells from men and pre-menopausal women blood donors. They found that cells from premenopausal women have much higher levels of protein called annexin-A1 on the surface of their white blood cells.

The scientists also found that annexin-A1 and estrogen levels were strongly linked throughout the menstrual cycle.

White blood cells play a vital role in protecting the body from infections. When they are activated they stick to the walls of blood vessels. This process normally helps the cells to tackle infection but if it happens too much, it can lead to blood vessel damage, which in turn can lead to cardiovascular disease. However, when annexin-A1 is on the surface of these white blood cells, it prevents them from sticking to the blood vessel wall.

The new research shows that estrogen can move annexin-A1 from inside the white blood cell, where it is normally stored, to the surface of the cells, thereby preventing the cells from sticking to blood vessel walls and causing vascular damage. This may have important implications in cardiovascular disease.

Dr Suchita Nadkarni from the William Harvey Research Institute, Queen Mary, University of London, who led the research, said: "We've known for a long time that estrogen protects pre-menopausal women from heart disease, but we don't know exactly why. This study brings us a step closer to understanding how natural estrogen might help protect our blood vessels.

"We've shown a clear relationship between estrogen levels and the behaviour of these white blood cells. Our results suggest that estrogen helps maintain the delicate balance between fighting infections, and protecting arteries from damage that can lead to cardiovascular disease.

"Understanding how the body fights heart disease naturally is vital for developing new treatments."

The study is published in American Heart Association journal Arteriosclerosis, Thrombosis and Vascular Biology. It was co-funded by the British Heart Foundation, the Wellcome Trust and the National Institutes of Health Research (NIHR).

15 Aug 2011

A simple reason to exercise
Posted by on August 10, 2011 - 8:28am

A healthy heart is like a rubber band. The more elastic it is, the better it works. A new study by Benjamin Levine at the Texas Health Presbyterian hospital in Dallas shows lifelong exercise can help your heart stay that way.

While starting to exercise late in life has its benefits, Dr. Levine says:  “You don’t want to wait too long if you want to try to make these major structural changes.”

Between the ages of 45 and 60 is when the heart typically starts to stiffen. To reduce those effects, exercise should be a conscious part of your daily routine. “Four to five days a week we think is the right dose to make sure that you have the maximum benefits.”

The study, supported by the National Institutes of Health, was presented at the annual scientific meeting of the American College of Cardiology.
Source;  HHS HealthBeat

An Apple a Day May Keep Bad Cholesterol Away!
Posted by on May 13, 2011 - 7:55am

A new study discovered that apples promoted good cholesterol levels in the participating women.   Researchers from Florida State University were surprised at the results of their study that included 160 females aged 45-85 randomly selected to received either 75 grams of dried apples or dried prunes for a whole year.  The apple consumption group significantly reduced the blood levels of total cholesterol and low density cholesterol (LDL- bad cholesterol) by 14% and 23%, respectively. Good cholesterol (HDL) increased in the study group by 4%.  The atherogenic  (plaque building) risk ratios of lipid  and C-reactive protein levels were also improved in the apple group.

The women in the study group also lost an average of 3.3 pounds even though the apples added another 240 calories to the usual daily diet.  Dr. Bahram Arjmandi who led the study, suggested that weight loss may be due to the pectin in apples which satisfies hunger.   Early animal studies had already suggested that apple and its components, e.g. apple pectin and polyphenols, improve lipid metabolism and lower the production of proinflammatory molecules. The authors believed that this study was the first  to look at the cardioprotective effects of daily consumption of apple for one year in postmenopausal women.

Of course, more studies will need to be done to reconfirm these results and look at the cellular interactions but we already know that apples are a good source of fiber, so why not have "an apple a day!"

 

Add Fiber Now, Avoid Heart Disease Later
Posted by on April 4, 2011 - 8:45am

High-fiber diets during early adult years may lower lifetime cardiovascular disease risk

A new study from Northwestern Medicine shows a high-fiber diet could be a critical heart-healthy lifestyle change young and middle-aged adults can make. The study found adults between 20 and 59 years old with the highest fiber intake had a significantly lower estimated lifetime risk for cardiovascular disease compared to those with the lowest fiber intake.  This is the first known study to show the influence of fiber consumption on the lifetime risk for cardiovascular disease.

“It’s long been known that high-fiber diets can help people lose weight, lower cholesterol and improve hypertension,” said Donald M. Lloyd-Jones, M.D., corresponding author of the study and chair of the department of preventive medicine at Northwestern University Feinberg School of Medicine. “The results of this study make a lot of sense because weight, cholesterol and hypertension are major determinants of your long-term risk for cardiovascular disease.”

A high-fiber diet falls into the American Heart Association’s recommendation of 25 grams of dietary fiber or more a day.  Lloyd-Jones said you should strive to get this daily fiber intake from whole foods, not processed fiber bars, supplements and drinks.

“A processed food may be high in fiber, but it also tends to be pretty high in sodium and likely higher in calories than an apple, for example, which provides the same amount of fiber,” Lloyd-Jones said.

For the study, Hongyan Ning, M.D., lead author and a statistical analyst in the department of preventive medicine at Feinberg, examined data from the National Health and Nutrition Examination Survey, a nationally representative sample of about 11,000 adults.  Ning considered diet, blood pressure, total cholesterol, smoking status and history of diabetes in survey participants and then used a formula to predict lifetime risk for cardiovascular disease.

“The results are pretty amazing,” Ning said. “Younger (20 to 39 years) and middle-aged (40 to 59 years) adults with the highest fiber intake, compared to those with the lowest fiber intake, showed a statistically significant lower lifetime risk for cardiovascular disease.”  In adults 60 to 79 years, dietary fiber intake was not significantly associated with a reduction in lifetime risk of cardiovascular disease. It’s possible that the beneficial effect of dietary fiber may require a long period of time to achieve, and older adults may have already developed significant risk for heart disease before starting a high-fiber diet, Ning said.

As for young and middle-aged adults, now is the time to start making fiber a big part of your daily diet, Ning said.

Erin White is the broadcast editor. Contact her at ewhite@northwestern.edu

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