Johns Hopkins Gazette: November 28, 1994


Cutting Fat in Kid's Diets Will Not Impair Their Development
By Mike Field

     Children with abnormally high cholesterol levels can safely
follow a low-fat diet without suffering a decline in growth,
anemia or learning problems, researchers at the School of
Medicine have found. Peter Kwiterovich, professor of medicine and
pediatrics, presented the findings of the three-year, multicenter
study at the American Heart Association's 67th Scientific
Sessions held earlier this month in Dallas. Though significant,
they represent only a small part of the ongoing research efforts
being conducted at the Hopkins Lipid Research Clinic and the
Lipid Research-Atherosclerosis Unit, which Dr. Kwiterovich has
headed since its inception in 1971.
     "Coronary artery disease is still the No. 1 cause of
morbidity and mortality in this country," Dr. Kwiterovich said.
"Heart disease, hypertension and stroke cost the economy
approximately $128 billion annually, and result in more than 1 
million heart catheterizations and surgical procedures each year.
And yet, out of all the people who develop early heart disease
only in one of 20 cases is the basis of the disease known."
     Dr. Kwiterovich has spent his career trying to find out what
makes the heart stop ticking, especially when it stops
prematurely. Early heart disease, defined as heart problems
occurring at age 55 or less in men, age 65 or less in women, is
slowly beginning to be understood. Dr. Kwiterovich has played a
significant role in developing the new understanding. In 1980, he
co-discovered hyperapoB, the most commonly recognized lipoprotein
disorder involved in the cause of premature coronary heart
disease. More recently, he and colleagues have discovered three
new proteins in human blood that permit the detection of a novel
cell abnormality in patients with hyperapoB and coronary heart
disease.
     "The Lipid Research-Atherosclerosis Unit is a
multidisciplinary effort that conducts research ranging from
clinical trials, such as the Dietary Intervention Study in
Children that examined the effects of low-fat diets in children,
to fundamental molecular and genetic research into the nature of
heart disease," Dr. Kwiterovich said. "In the middle, we work
with families with a history of heart disease performing DNA and
blood tests to try to identify and predict risk factors."
     The Dietary Intervention Study in Children screened more
than 47,000 eligible boys and girls aged 8 to 10 in Baltimore,
Chicago, Iowa, New Jersey, New Orleans and Portland to select 663
participants with abnormally high levels of cholesterol. Half of
the children and their parents, assigned to the intervention
group, were subject to six months of intensive, behaviorally
oriented classes in shopping, food preparation and eating a
low-fat diet. The other half was put in the usual care group
where they received a general diet information packet and no
additional counseling.
     The intervention group subjects significantly reduced their
cholesterol level over the usual care group during the study. Yet
each group showed an average height increase of 8 inches during
the length of the study, nor was there a difference in the blood
ferritin levels between the groups, indicating the low-fat diet
was not deficient in iron. No significant differences were found
for any secondary outcome measures such as serum zinc, folate,
retinol or albumin, nor did the reduced-fat diet affect the onset
of sexual maturation, measures of cognitive development or child
behavior.
     "We concluded the low-fat diet was effective and safe in
rapidly growing boys and girls with elevated low-density
lipoprotein cholesterol levels," Dr. Kwiterovich said. "These
results are important for healthy children, aged 2 and older, who
suffer from excessively high levels of LDL cholesterol because
they indicate safe, effective treatment is available. We
recommend that if children have a family history of premature
heart disease--if a parent, grandparent, aunt or uncle was
affected--then the child should be brought in for a complete
blood lipid profile some time after the age of 2."
     Though intensive intervention appeared successful at
reducing cholesterol levels over a three-year period, it is
unclear how significant the benefits will be or how long the
changed behavior will last. 
     "The hard part of the low-fat diet is fast food," Dr.
Kwiterovich said. Whether the study group can survive the
teen-age years without large helpings of hamburgers, fries and
pizza remains to be seen. The second phase of the study,
currently in progress, will follow the participants until they
reach the age of 18.
     "Knowledge is not always translated into behavioral change,"
Dr. Kwiterovich said. "Subjects in the intervention group
participated in 12 weeks of classes in a social setting that
focused on substitution rather than elimination. Ground round
steak is only 8 percent fat; you can mix that with ground turkey,
top it with low fat cheese and you've got a great cheeseburger."
It is not known, however, if high-chol-esterol, high risk
teen-agers will eat low-fat cheeseburgers eight or even 10 years
after intervention.
     Meanwhile, Dr. Kwiterovich directs research aimed at
discovering what causes heart disease to develop. Researchers in
his lab recently received a grant from the National Institutes of
Health to re-examine high-risk families ascertained from 1985 to
1988 in the Hopkins Coronary Artery Disease Study. They will
examine the genetic basis of hyperaboB and premature heart
disease.
     "We believe a receptor gene defect is present in a number of
fanilies with early heart disease, and we are using cell biology
and molecular biology to take an in-depth look," he said. "One
out of three subjects with early heart disease has hyperaboB,
which characterizes the presence of small, dense LDLs that
contribute to heart disease."
     If the relationship between cellular defect and heart
disease proves reliable, it could be a major step forward in
identifying potential heart disease victims far enough in advance
to introduce prophylactic dietary or drug therapies, he said. 
     "We feel as though we're on the verge of a breakthrough,"
Dr. Kwiterovich said. "Our goal is to discover an important cause
of heart disease, and thus create better tools for the diagnosis
and treatment of the country's No. 1 killer."
     Individuals with a family history of premature heart disease
can arrange a complete blood profile to reveal risk factors
through the Lipid Clinic. Call 955-3197 for details.

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