High Blood Pressure Can Lower Fat Metabolism
According to research published in the June 2006 issue
of the Journal of Nuclear Cardiology, the hearts of patients
with muscle thickening (hypertrophy) due to high blood
pressure (BP) have an energy metabolism that fails to use
fat as energy. Researchers from Washington University
explained that these hearts get less energy because of their
reduced fat metabolism, which leads them to rely more
heavily on carbohydrates, which produce less energy per
molecule than fatty acids.
"With hypertrophy, the heart has a higher energy
demand because there's more muscle to feed," the
investigators explained. "With less fat metabolism, a
greater reliance on carbohydrates may represent a shift
to a less-efficient fuel."
The researchers studied patients who had high BP
that led to hypertrophy and found that the greater the
muscle mass of the hypertrophic heart the lower the
ability to burn fat. A normal heart muscle alternates
between using fats and carbohydrates as fuel, depending
on availability. When people with a hypertrophic
heart experience low blood sugar, however, their hearts
cannot switch to fatty acids as normal hearts would,
leaving them energy-deficient.
Low-fat Dairy Could Help Lower BP
According to a report published in the August 2006 issue of
Hypertension: Journal of the American Heart Association, eating
low-fat dairy products could help lower blood pressure (BP).
The researchers used data from food questionnaires filled out
by 4797 men and women who were participating in the
National Heart, Lung, and Blood Institute's Family Heart Study.
The participants had an average age of 52 years. They were
enrolled in the study to help determine genetic and nongenetic
causes of coronary heart disease, atherosclerosis, and cardiovascular
risk factors, such as hypertension.
The researchers, led by Luc Djoussé, MD, MPh, DSc, of the
Division of Aging at Brigham and Women's Hospital and Harvard
Medical School, Boston, Mass, found that those who ate more
dairy products had lower systolic BP. When divided into groups
based on the number of servings eaten daily, those who ate the
most had systolic BP readings of 2.6 mm Hg lower than those
who ate the fewest. These people also had a 36% lower chance
of having high BP. The greatest positive effects, however, were
shown in those who ate dairy products with the lowest amount
of saturated fats. In these groups, those who consumed more
dairy products (with less fat) had systolic BP readings of 3.5 mm
Hg lower and had a 54% lower chance of having high BP than
those who ate fewer.
Hypertension Could Limit Walking Ability in Seniors
The findings of a study by researchers at Rush
University Medical Center in Chicago, Ill, suggest that
higher blood pressure (BP) could be linked to a decline in
walking ability as patients get older. The study results
were published in the August 2006 issue of the Journal
of Gerontology: Medical Sciences.
Researchers studied 888 elderly Catholic clergy who
are participating in the Religious Orders Study. The investigators
measured the participants' BP at baseline,
established the presence of vascular diseases and diabetes,
assessed cognitive function, and noted medications.
They assessed gait and balance throughout the
study using performance-based tasks, including the time
and number of steps taken to walk 8 feet, the time to sit
up and down 5 times, and the ability to stand with eyes
open and eyes closed.
Controlling for age and gender, the researchers found
that a 10-mm Hg increase in systolic BP was associated
with a greater decline in lower limb function. On average,
lower limb function was reduced 28.7% faster in
patients with a systolic BP of 160 mm Hg than in those
with a normal systolic reading.
Exercise Encouraged to Reduce Hypertension
A US study has reinforced the benefits
of exercise in seniors with mildly
high blood pressure (BP). These patients
should be cautious, however,
because exercise tends to raise BP initially
and could lead to adverse cardiac
effects. Elderly patients should consult
with their physicians before taking up
any form of exercise.
Researchers at Johns Hopkins University
School of Medicine in Baltimore,
Md, performed the analysis. They studied
the effects of exercise on cardiac size and
left ventricular function of older men and
women participating in the Senior Hypertension
and Physical Exercise (SHAPE)
study. The patients were randomly
assigned either to participate or not to participate
in supervised exercise for 1 hour a
day 3 times a week.
After 6 months, those who exercised
had higher peak oxygen intake on a
treadmill, greater strength, and lower
body fat, diastolic BP, and insulin resistance
than those who did not exercise.
The results of the study were published
in the July 2006 edition of Heart.