APRIL 01, 2008

High BP: Blame Familial Link

A 54-year-old study has firmed up the link between parents' high blood pressure (BP) and the odds their offspring will develop the condition. Whereas a history of hypertension is well-established as a warning sign, the current study has some unique components.

For example, the huge amount of data. The study followed 1160 men in a study that began in 1947, when the participants were medical students, and took annual measurements of their BP over the next 5 decades. The researchers also were able to classify the potential risk much better.At the start of the study, 264 participants reported at least one parent with high BP, whereas only 20 had both parents with high BP. At the end of the study, 583 new cases of parental hypertension were diagnosed, translating into 60% of the group with at least one parent with the condition and 14% with 2 parents.

Reporting in the March 24, 2008, issue of the Archives of Internal Medicine, lead author Nae-Yuh Wang, PhD, said, "What we found was that if parents have hypertension early, their children have a significantly higher risk of developing hypertension at an early age." He added, "If the parents develop hypertension at age 55 or earlier, the lifetime risk for the children is 7-fold higher than normal."

Alcohol May Boost BP, Study Says

Even moderate alcohol consumption may increase blood pressure (BP) more than previously thought. Earlier studies have associated heavy drinking with high BP whereas other studies have suggested that moderate alcohol consumption provides health benefits such as lowering cholesterol.

In the current study, reported recently in PLoS Medicine, the researchers found that individuals with a genetic mutation that makes it hard to drink alcohol had a considerably lower BP than regular and heavy drinkers. Individuals without the genetic mutation who consumed 3 drinks per day had "strikingly" high BP, compared with individuals with the genetic change who drank small quantities or abstained. The researchers reported that there is >2-fold risk for high BP among drinkers and a 70% increased risk for "quite modest" drinkers, compared with individuals with the genetic mutation. "Reporting of alcohol (in other studies) is likely to be subject to considerable error, and this error may be differential— for example, people who have been advised to reduce alcohol intake for medical reasons may under-report alcohol intake," said the researchers.

Marital Bliss, Good BP

A Brigham Young University study found that happily married couples have lower blood pressure (BP), compared with unhappy married couples or singles. On the other hand, even a supportive, social network did not mean a BP benefit for singles or unhappy married couples, according to a study reported in the March 20, 2008, issue of the Annals of Behavioral Medicine.

"There seem to be some unique health benefits from marriage. It's not just being married that benefits health—what's really the most protective of health is having a happy marriage," explained study author Julianne Holt-Lunstad, PhD, a psychologist who specializes in relationships and health.

For the study, 204 married couples and 99 single adults wore portable BP monitors for 24 hours. The monitors recorded BP at random periods and provided a total of 72 readings. The researchers found that overall, happily married couples scored 4 points lower on the BP readings, compared with single adults.The study also showed that BP among married individuals—especially those in happy marriages— dipped more during sleep than in single individuals.

"We wanted to capture participants' blood pressure doing whatever they normally do in everyday life. Getting 1 or 2 readings in a clinic is not really representative of the fluctuations that occur throughout the day," she said.

Smoking Ups Stroke Risk for High BP Patients

Data on 563,144 individuals showed that smoking boosts the increased risk of a hemorrhagic stroke for patients with high blood pressure (BP), according to a study reported in the March 2008 issue of Stroke.

At the study onset, more than a third of the participants were smokers. During 6.8 years of follow-up, 746 of the 210,961 smokers and 899 of the 352,183 nonsmokers had a hemorrhagic stroke. The researchers found that for every 10 mm Hg increase in systolic BP smokers faced an 81% increased risk of hemorrhagic stoke, compared with 66% increased risk for nonsmokers.

Specifically, smokers with the highest systolic BP readings (150 mm Hg or greater) were 9.3 times more prone to have a stroke, compared with smokers with the lowest readings (120 mm Hg or less).

The nonsmoker participants with the highest systolic BP readings were 7 times more apt to experience a hemorrhagic stroke, compared with the patients with the lowest readings.

F A S T   F A C T : Of the individuals with diabetes, 60% also have high blood pressure.