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HICNet Medical News Digest      Sun, 01 Oct 1995        Volume 08 : Issue 34

Today's Topics:

  Bypass Over Angioplasty for Patients with Diabetes
  Job Strain Not Predictor of Heart Attack
  "Subclinical" heart/blood vessel disease easily detected
  Women Gain Beneficial Changes Cholesterol during Cardiac Rehab
  Cholesterol Levels Predict Extent of Artery Narrowing

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             Lawrence Lee Miller, B.S. Biological Sciences, UCI

            Dr K C Lun, National University Hospital, Singapore

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Date: Fri, 22 Sep 1995 06:59:24 -0700
From: David Dodell <david@dental.stat.com>
To: hicnews
Subject: Bypass Over Angioplasty for Patients with Diabetes
Message-Id: <199509221359.GAA07476@nntp1.news.primenet.com>

                                         September 21, 1995


                      CLINICAL ALERT FROM
         THE NATIONAL HEART, LUNG, AND BLOOD INSTITUTE,
                 NATIONAL INSTITUTES OF HEALTH,

       BYPASS OVER ANGIOPLASTY FOR PATIENTS WITH DIABETES


The National Heart, Lung, and Blood Institute (NHLBI), part of
the National Institutes of Health, today announced that, as a
first revascularization procedure, coronary artery bypass graft
(CABG) surgery has been shown to have a markedly lower 5-year
death rate than angioplasty for persons with diabetes mellitus
(Type I or II) who are on oral hypoglycemic agents or insulin.

The finding came from the NHLBI-funded Bypass Angioplasty
Revascularization Investigation (BARI).  The multicenter,
international, randomized trial studied patients who needed a
first revascularization because of severe ischemia with
obstructions in two or more major coronary arteries.  Over 5
years, patients with diabetes mellitus who were on drug therapy
had a significantly lower (p=0.002) mortality rate with CABG,
compared with percutaneous transluminal coronary angioplasty
(PTCA).  The 5-year CABG mortality rate was 19 percent, compared
with 35 percent for PTCA.  By contrast, in patients without
diabetes and in those with diabetes but not on drug treatment,
the 5-year mortality rates for CABG and PTCA were both about 9
percent.

The higher death rate for PTCA was not due to complications of
the procedure itself.  Those with diabetes are known to have an
excessive cardiovascular risk and a higher mortality rate was
expected for them, regardless of revascularization procedure.
However, the excess mortality with PTCA had not been
anticipated.

BARI's results indicate that CABG should be the preferred
treatment for patients with diabetes on drug or insulin therapy
who have multivessel coronary artery disease and need a first
coronary revascularization.  These results have a significant
impact on the clinical care of these patients.

Coronary revascularization plays an important role in the
treatment of clinically severe coronary artery disease.  The two
most commonly used methods of revascularization are CABG and
PTCA.  PTCA is a catheter-based nonsurgical approach that
directly targets coronary obstructions by dilation of the vessel
at the point of obstruction.  The process is accompanied by local
vascular injury and subsequent healing.  The extent of injury and
the healing process may be different in diabetic and nondiabetic
patients.  Not all lesions can be dilated, due largely to
technical reasons.  CABG is a major operation, requiring opening
of the chest.  It provides a new channel, with a lumen frequently
larger than the native, diseased lumen.  There is no
instrumentation of the local lesion and, therefore, no related
vascular injury.  While both treatments alleviate the effects of
coronary artery disease, they do not correct or alter the natural
course of the disease.

Before PTCA, CABG was the traditional revascularization
strategy.  But PTCA, first performed in the United States in
1977, has grown rapidly in use.  In 1993, about 362,000 PTCAs
were done in the United States, compared with about 309,000 CABG
surgeries.

However, PTCA use has expanded not just in number but also in the
type of patient treated.  Initially, PTCA was done on patients
with one obstructed vessel.  But, with increased physician
expertise and an improved technology, PTCA use has rapidly
expanded to include patients with more complex, multivessel
coronary obstructions, once treated exclusively with CABG.  This
has led to uncertainties about the longterm effectiveness and
safety of PTCA compared with CABG and prompted the NHLBI to fund
a rigorous evaluation of the two methods.

That rigorous investigation--the BARI study--tests whether the
use of PTCA as an initial treatment compromised the clinical
outcome for patients with multivessel coronary artery disease who
needed revascularization and could be treated by either PTCA or
CABG.  BARI did not test outcomes for repeat procedures.  It also
studied only PTCAs performed with the standard balloon
technique.

The trial is the largest randomized study of its type, with
enough patients to be able to address key endpoints, both overall
and in predetermined patient subgroups.  The subgroups were based
on patients' anginal status, number of diseased vessels, and left
ventricular function.  Also studied are various demographic
factors such as gender, age, race, and the presence of diabetes.

The primary endpoint is mortality after 5 years of followup.
Other important endpoints include the occurrence of a myocardial
infarction, need of repeat revascularization procedures, angina,
functional status, quality of life, and utilization of
health-care resources.  (Both quality of life and utilization of
health-care resources are studied in detail in a separately
funded ancillary study.)

Patients were eligible for the trial if they had coronary artery
disease with a 50 percent or more luminal obstruction (as
measured by calipers) in at least two of the coronary vessels
supplying two or three major coronary territories.  They also had
to have clinically severe ischemia but not a prior
revascularization.  Patients were ineligible for the trial if
they had, for example, insufficient angina or ischemia, required
emergency revascularization, left main stenosis of 50 percent or
greater, a noncardiac illness expected to result in limited
survival, primary coronary spasm, or a poor quality angiogram.
Baseline angiograms were reviewed and classified by the Central
Radiographic Laboratory (Dr. Edwin L. Alderman, director) at the
Stanford University Medical Center in Palo Alto, CA.

Between August 1988 and August 1991, 18 clinical centers
randomized 1,829 patients, ages 17 to 80 and including 353 on
drug treatment for diabetes.  Half of the patients were randomly
assigned to PTCA and the other half to CABG.  At baseline, the
mean age of the randomized patients was 61 years.  Thirty-nine
percent of the randomized patients were age 65 or older, 27
percent were women, 25 percent were classified as having diabetes
(of these, 76 percent were being treated with oral hypoglycemic
agents or insulin), 60 percent had two-vessel disease and 40
percent had three-vessel disease, and 98 percent had angina (of
these, 64 percent had unstable angina and 17 percent had class
3-4 angina).  At the time of this alert, 66 percent of patients
had completed followup.  Patients will be followed for a minimum
of 7 years.  The trial is expected to finish followup on all
patients by November 1998.

Followup includes annual functional status assessments and an
electrocardiogram (ECG), and a biennial exercise stress test.  As
required by the protocol, risk factor modification was initiated
for all patients after their enrollment.  This includes help with
smoking cessation, exercise, and diet.  Patients also were
treated as needed for hypertension, elevated blood cholesterol,
and diabetes.  Risk factors and medical problems were managed by
each patient's primary care physician.

The trial has been closely monitored by both the study chairman
(Dr. Robert Frye, Mayo Clinic Foundation), the Clinical
Coordinating Center (Dr. Katherine Detre, University of
Pittsburgh), and the independent Data and Safety Monitoring Board
(chaired by Dr. J. David Bristow, Oregon Health Sciences
University).  The Data and Safety Monitoring Board is composed of
PTCA experts, cardiovascular surgeons, clinical cardiologists,
and experts in biostatistics and ethics.  The Board regularly
reviews the monitoring reports.  ECG analyses are being done by
the Central ECG Laboratory (Dr. Bernard R. Chaitman, director) at
the St.  Louis University Medical Center.  An independent
Mortality and Morbidity Classification Committee (chaired by Dr.
Ronald Prineas, University of Miami) categorizes fatal events in
the trial.

On September 13, 1995, the Data and Safety Monitoring Board held
an urgent session to review the 5-year mortality data.  The Board
concluded that the unfavorable mortality results for the patients
on drug treatment for diabetes and first treated with PTCA were
unlikely to be due to chance.  The Board recommended to the
National Institutes of Health that physicians and other health
care professionals and the public be promptly informed of the
results.

In summary:  BARI's findings should not be applied to all persons
with diabetes.  They apply only to those on oral hypoglycemic
agents or insulin for diabetes and who have multivessel coronary
artery disease and are undergoing an initial revascularization
procedure.  The data offer the following guidelines for such
patients: They will probably fare better with CABG than PTCA as
an initial treatment.  For patients who have already had a PTCA
and are asymptomatic--experiencing no ischemia, angina, or other
symptom--they should take no special action but continue their
regular care.  Alternatively, if they have already had a PTCA and
had their ischemia return (e.g., reappearance of angina), they
should consult their physicians to assess their current health
status and review optimal strategies for further care.  Close
physician monitoring is particularly important for patients with
diabetes who have coronary artery disease, since they may not
experience symptoms during periods of ischemia.

Finally, all patients who have evidence of coronary artery
disease, with or without a prior PTCA or CABG, should receive an
aggressive approach to medical management of known risk factors
for coronary artery disease, including smoking cessation for
smokers, appropriate control of elevated blood pressure or serum
cholesterol, and optimal control of diabetes.
---
Internet : david@dental.stat.com
Telephone: +1-602-860-1121
FAX      : +1-602-451-1165


------------------------------

Date: Wed, 27 Sep 1995 13:04:55 -0700
From: David Dodell <david@dental.stat.com>
To: hicnews
Subject: Job Strain Not Predictor of Heart Attack
Message-Id: <19950927130500.19670889.in@dental.stat.com>

Job strain not a predictor of heart attack in patients

American Heart Association Press Release
        August 1, 1995

        DALLAS, Aug. 1 -- Although psychological stress in the
workplace is widely believed to increase the risk of
coronary heart disease, scientific evidence supporting this
belief "is relatively sparse," according to scientists
publishing a new study.  Their research suggests that job
strain is not an important coronary risk factor.
        After a four-year study of 1,489 patients who had
undergone coronary angiography, a test to detect blockage of
coronary arteries, the researchers report:  "The outcome of
patients with angiographically defined coronary disease was
not affected by the level of job strain."  Their findings
appear in the Aug. 1 issue of the American Heart Association
journal Circulation.
        The scientists were surprised to find job strain was
actually more common in patients with normal coronary
arteries than in patients with diseased vessels, says Mark
A. Hlatky, M.D., principal author of the new study.
        This is the first investigation of job strain to use
coronary angiography to confirm the presence and severity of
coronary disease, notes Hlatky, associate professor of
health research and policy and of cardiovascular medicine at
Stanford University School of Medicine, Stanford, Calif.
This method is more reliable than those used in previous
studies of job strain and coronary disease, he says, since
it shows the degree of cholesterol buildup within the heart
by use of X-ray pictures.  Some patients with job stress and
chest pain do not have evidence of heart disease on their
coronary angiograms.
        The researchers studied patients tested for heart disease
at Duke University Medical Center in Durham, N.C., between
March 1986 and June 1990.  Those who agreed to participate
filled out questionnaires that assessed their job duties and
work environment, including a measure of job strain.
        "Previous studies did not measure job strain directly in
each patient as we were able to do," says Hlatky.  "This is
important, because the amount of job strain varies from
person to person, even with the same job title."  Job strain
was defined in the study as high psychological demands from
work but little ability to control the pace or amount of
work on the job.
        Their study found that coronary disease was just as common
in the patients with low levels of job strain as it was in
patients with high levels of job strain, the researchers
report.  Patients with low job strain were just as likely as
the patients with high job strain to have heart attacks or
die from heart disease over the four years after
angiography.
        The four-year average follow-up was long enough and the
number of patients studied was large enough to show an
effect of job strain on the rate of heart attacks and death,
says Redford B. Williams Jr., M.D., a co-author of the
study.  "All of the other psychosocial risk factors, such as
hostility, depression and social isolation, that predict
high rates of cardiac events are predictive within the first
four years," he says.
        Why does job strain not appear to add to the risk of heart
disease?  "People who are able to keep working may benefit
from the social contacts at work, even if they have a high-
strain job," speculates Williams, director of behavioral
research at Duke University and author of the book, Anger
Kills.  Several studies have shown that coronary patients
who are socially isolated have a much higher death rate, he
says.
        Stress from a person's job is also only a fraction of the
overall stress of daily life, notes Hlatky.
        Ninety-two percent of the 1,489 patients enrolled in the
study of job strain considered coronary heart disease to be
a disorder of modern industrial society.  "Popular culture
accepts that the stress of modern life in general and the
modern workplace in particular have contributed to the rise
of coronary heart disease over the Twentieth Century," the
researchers write in Circulation.
        "A major difficulty in stress research has been the
inherent complexity and subjectivity of the concept and the
attendant difficulties in the measurement of stress," the
authors continue.  "The same job conditions, for instance,
may be viewed by one person as challenging and by another
person as stressful."
        Other possible sources of stress on the job should be
measured in future studies, they suggest, "such as low job
security, inadequate pay, interpersonal conflicts with co-
workers or customers, irregular schedules, or the
difficulties of juggling family demands and work demands."
        Co-authors of the study with Hlatky and Williams are Lai
Choi Lam, M.S.; Kerry L. Lee, Ph.D.; Nancy E. Clapp-
Channing, M.P.H.; David B. Pryor, M.D.; Robert M. Califf,
M.D., and Daniel B. Mark, M.D., M.P.H.
---
Internet : david@dental.stat.com
Telephone: +1-602-860-1121
FAX      : +1-602-451-1165


------------------------------

Date: Wed, 27 Sep 1995 13:06:36 -0700
From: David Dodell <david@dental.stat.com>
To: hicnews
Subject: "Subclinical" heart/blood vessel disease easily detected
Message-Id: <19950927130640.196892e1.in@dental.stat.com>

Subclinical' heart and blood vessel disease easily detected

American Heart Association Press Release

        DALLAS, Aug. 15 -- The early signs and signals of heart
disease and stroke are present in the blood vessels long
before widely applied diagnostic tests and risk factor
information can detect them.
        Now a group of physicians and scientists in the
Cardiovascular Health Study say that without relying solely
on known factors -- high blood pressure, high blood
cholesterol, cigarette smoking and sedentary lifestyle -- to
assess risk, they have been able to detect "subclinical"
vessel disease that reliably warns of problems ahead for
people ages 65 and over.
        Participants who had subclinical disease -- that is,
disease without symptoms -- were two to three times as
likely to have a heart attack (either fatal or non-fatal) or
angina independent of other risk factors, says Lewis H.
Kuller, M.D., Dr.P.H., senior author of the report.
        The researchers base their findings on four technician-
administered tests that are relatively inexpensive,
according to their report published in today's (Aug. 15)
American Heart Association journal Circulation.
        If these test results are widely applied in medical
practice, they say, it would be possible to institute such
preventive measures as a low-fat, low-cholesterol diet, drug
therapy and exercise and reduce the risks of future heart
attacks or strokes in millions of high-risk older Americans.
        Kuller and his co-authors add: "Many older individuals
without subclinical disease, even those with increased risk
factors such as high cholesterol level, are at low risk of
developing clinical coronary artery disease and might not
benefit from specific aggressive therapies.  If such
treatments are relatively costly, i.e., drug therapy is
expensive, or treatment may cause serious side effects, then
the cost of such therapy may be greater than the benefits."
        Testing for subclinical disease before beginning
therapies could focus risk-reduction efforts on higher-risk
individuals who are more likely to develop clinical disease
within the next few years -- those who would benefit most,
the authors suggest.
        The CHS participants were 5,20l adults -- 2,239 men and
2,962 women -- from four regions of the United States.  They
were given four tests in clinics and hospitals and followed
by telephone over a period of about three years to record
their health status and events such as heart attack and
stroke.
        One test records blood pressure in the ankle and compares
the reading to blood pressure in the arm.  A lower reading
in the ankle is a sign of early blockages in peripheral
vessels.
        In a second test called duplex ultrasound, a technician
places a probe on the skin outside a main neck artery called
the carotid. By bouncing sound waves off the blood flowing
through the artery, the machine determines the rate of blood
flow and thickness of the artery.  Diseased arteries tend to
be thicker than healthy ones.  If the artery is constricted,
blood tends to flow faster and at higher pressure, producing
characteristic sounds.
        Each participant was also examined to see whether their
heart's  electrical system was properly controlling each
heartbeat.  An abnormal electrocardiogram is a sign of
subclinical disease. And all patients answered a
questionnaire designed to see whether they had experienced
heart and/or leg pain.  Yes answers were a fourth indicator
of disease.
        Patients in the study were from Forsyth County, N.C.;
Sacramento County, Calif.; Washington County, Md., and
Pittsburgh, Pa.  Whites composed 95 percent of the group,
blacks the remaining 5 percent.
        The researchers, including Kuller, who is on the faculty
at the University of Pittsburgh Graduate School of Public
Health, believe their study has uncovered "subclinical
disease" as a candidate risk factor for clinical heart
disease in older people.
        "The pathway from risk factors to clinical disease
probably is through the development of subclinical disease,"
the authors say.  Subclinical disease may be a marker for
the effects of the known risk factors and such contributing
factors as diabetes, obesity and family history.

Other co-authors are Lynn Shemanski, Ph.D.; Bruce M.
Psaty, M.D., Ph.D., and Nemat O. Borhani, M.D., of the
University of Washington School of Medicine, Seattle; Julius
Gardin, M.D., University of California-Davis; Mary N. Haan,
M.D., University of California-Sacramento; Daniel H.
O'Leary, M.D., Geisinger Medical Center, Danville, Pa.;
Peter J. Savage, M.D., National Heart, Lung, and Blood
Institute, Bethesda, Md.; Grethe S. Tell, Ph.D., Bowman Gray
School of Medicine, Winston-Salem, N.C., and Russell Tracy,
Ph.D., University of Vermont, Colchester.
        The Cardiovascular Health Study is supported by funds
from the National Heart, Lung, and Blood Institute.
---
Internet : david@dental.stat.com
Telephone: +1-602-860-1121
FAX      : +1-602-451-1165


------------------------------

Date: Wed, 27 Sep 1995 13:08:34 -0700
From: David Dodell <david@dental.stat.com>
To: hicnews
Subject: Women Gain Beneficial Changes Cholesterol during Cardiac Rehab
Message-Id: <19950927130840.196a5fbc.in@dental.stat.com>

Women gain more beneficial cholesterol changes during rehab


American Heart Association Press Release


        DALLAS, Aug. 15 -- Women with heart disease who
participate in a cardiac rehabilitation program may achieve
greater beneficial changes in their cholesterol levels than
men, according to a new study.
        "Most cardiac rehab programs until now have been full of
men, but maybe our findings will convince women that they
should participate, too," says James G. Warner Jr., M.D.,
lead author of the study and assistant professor of
cardiology at Bowman Gray School of Medicine, Winston-Salem,
N.C.
        Among a group of patients taking part in one of the
longest-running rehabilitation programs for heart patients,
Warner and his colleagues found 166 female participants were
able to lower their risk of heart attack more than 553 male
participants, the scientists report today (Aug. 15) in the
American Heart Association journal Circulation.
        All of the cholesterol levels improved more in the women:
(1) HDL, their "good" cholesterol, increased by 20 percent
compared to a five percent increase in the men; (2) LDL
cholesterol, the "bad" form, dropped by 34 percent compared
to 15 percent in the men; and (3) women's total cholesterol
decreased overall by 20 percent versus only eight percent in
the men.
        The 719 men and women, mean ages 57 and 59, respectively,
participated in the Wake Forest Cardiac Rehabilitation
Program between Jan. 1, 1988, and Jan. 1, 1994.  They
exercised three days a week for up to five years.  Each
exercise session involved 10 minutes of stretching followed
by 30 to 40 minutes of walking, jogging or riding a
stationary bicycle.
        All patients were counseled on low-cholesterol and low-fat
diets, the scientists report.  The percentage of men and
women on cholesterol-lowering drugs was similar, and only six
percent of the women were taking estrogen supplements.
        The research project is one of the largest "observational"
studies to examine the effects of exercise on HDL-cholesterol
and other blood fats in patients undergoing cardiac
rehabilitation and to compare the effects on men and women,
the investigators point out.
        "A limited number of (earlier) studies showed a favorable
effect of exercise on HDL-cholesterol in cardiac
rehabilitation patients," they say.  "However, most of these
studies had small numbers of subjects and short training
periods and were conducted almost exclusively in men."  So
the researchers designed their study to compare changes in
HDL and other lipids (fats) in a large group of men and women
taking part in a rehab program for five years.
        Men in the study showed approximately the same beneficial
increase in HDL-cholesterol as the women during the first
year of exercise.  "But over the next four years, there was
no further increase" in the men, the authors report.  "It is
unclear why HDL-cholesterol remained essentially unchanged
after one year in men and continued to rise over five years
in women."
        "We were surprised that the men plateaued after one year,"
says Warner.  One possible factor is that the women started
at lower overall fitness levels, based on measures of aerobic
capacity, and thus had "more room for improvement," he points
out.
        Even if they don't benefit as much as women do, men should
continue to participate in cardiac rehab programs -- "because
if they quit, the beneficial effects (of past efforts)
probably will disappear," Warner says.
        Because studies by others have suggested that each one-
milligram-per-deciliter (mg/dl) increase in blood level of
HDL-cholesterol reduces the risk of heart attack by more than
two percent, Warner estimates that the five percent increase
in HDL levels in men does represent, at least in theory, a
significant 10 percent decrease in their heart attack risk.
        The 20 percent increase in HDL -- and the accompanying
theoretical 40 percent decrease in heart attack risk -- seen
in the exercising women was as good a result as they could
hope to achieve with the best drug therapies, says David M.
Herrington, M.D., senior author of the study and associate
professor of medicine at Bowman Gray.
        But at this point, the researchers have not shown that the
improvements they observed in cholesterol levels actually
translate into lower rates of heart attacks and higher rates
of survival.  Warner, Herrington and their co-workers plan to
continue to follow the same 719 patients to see which ones go
on to have heart attacks.
        Future studies also are needed to clarify the mechanism
through which exercise affects HDL-cholesterol and other
lipids in women and men, the scientists say.
        Female hormones including estrogen probably play an
important role, notes Warner, because after menopause, a
woman's risk of heart attack rises until it eventually
matches that faced by men.  "It's known that until women
reach menopause, they have higher HDL-cholesterol than men,"
he says.
        Other co-authors of the study are Peter H. Brubaker,
Ph.D.; Ying Zhu, M.S.; Timothy M. Morgan, Ph.D.; Paul M.
Ribisl, Ph.D., and Henry S. Miller, M.D.
---
Internet : david@dental.stat.com
Telephone: +1-602-860-1121
FAX      : +1-602-451-1165


------------------------------

Date: Wed, 27 Sep 1995 13:10:16 -0700
From: David Dodell <david@dental.stat.com>
To: hicnews
Subject: Cholesterol Levels Predict Extent of Artery Narrowing
Message-Id: <19950927131019.196bedf0.in@dental.stat.com>

Cholesterol levels predict extent of artery narrowing

American Heart Association Press Release


        DALLAS, Aug. 9 -- Cholesterol levels in the blood appear
to be an accurate barometer of the amount of fatty plaque
clogging a person's coronary arteries, according to a
multicenter European study.
        The investigators say that blood cholesterol levels are a
"strong and independent" link to coronary artery disease
(CAD) and heart attack risk.  Their report appears in the
August issue of the American Heart Association journal
Arteriosclerois, Thrombosis, and Vascular Biology.
        Researchers used angiograms, a type of X-ray, to peer
inside the coronary arteries of 2,587 men and women at 18
European medical centers.  All the patients had "angina"
chest pain resulting from narrowed coronary arteries.  Those
who had the highest blood cholesterol had the most severe
narrowings, reports the study's co-author, Dr. Simon
Thompson of the Medical Statistics Unit at London's School
of Hygiene and Tropical Medicine.
        This is the first time that researchers have
comprehensively linked the actual level of cholesterol and
other lipids to the amount of coronary artery disease in
such a large study, researchers say.=7F
        "The implications of this study are that cholesterol, HDL
and LDL are major culprits in CAD, and that dietary
recommendations concerning cholesterol should be stringently
maintained," says Thompson.
        Cholesterol is piggy-backed through the bloodstream in
particles of HDL (high-density lipoprotein) and LDL (low-
density lipoprotein).  Population studies have shown that
risk of heart attack increases when total cholesterol and
LDL levels are elevated and levels of "good" HDL are low.
        In their study the European investigators used a scoring
system of 0 to 4 to classify patients, with the lowest score
indicating no narrowing and the highest score indicating
blockages of at least 50 percent in all four coronary
arteries studied.  Blood concentrations of the major lipids
-- including total cholesterol, HDL cholesterol and LDL
cholesterol -- were measured.
        The researchers also measured triglycerides and a fat
particle called lipoprotein(a) that may adversely affect
blood clotting.
        Patients were placed in one of three groups, based on
their lipid levels.  Those in the highest third had a 3.84-
fold higher incidence of CAD than those with serum levels in
the remaining two thirds.  Individuals in the highest third
for triglycerides and Lp(a) had about 1.5 times greater risk
than those in the lowest third.
        The findings provide clear evidence that all of
cholesterol -- including LDL and HDL -- is "strongly related
to the presence and extent of coronary artery disease" and
this underlies their importance as predictors of heart
disease risk, the scientists say.
        "Arteriosclerotic diseases are multifactorial in origin,
and risk of heart attack has been found to be related to
cholesterol, LDL and HDL, but it has not before been so
clearly shown how serum lipid profiles are related to the
extent of coronary artery disease," says Thompson.=7F

        Co-authors with Thompson are Dr. Ignasi Bolibar, Dr.
Arnold von Echardstein, Dr. Martin Sandkamp and Professor
Gerd Assmann.
---
Internet : david@dental.stat.com
Telephone: +1-602-860-1121
FAX      : +1-602-451-1165


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End of HICNet Medical News Digest V08 Issue #34
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Editor, HICNet Medical Newsletter
Internet: david@stat.com                 FAX: +1 (602) 451-6135