Obesity alone not linked to fatal heart attacks

NEW YORK (Reuters Health) – Being overweight or obese, in
the absence of high blood pressure, does not clearly increase
the risk of death from heart attack or stroke, French
researchers report in the journal Hypertension: Journal of the
American Heart Association.

“The role of obesity and overweight as independent risk
factors for (heart attack and stroke) is still debated,” Dr.
Athanase Benetos and colleagues from the Center
d’Investigations Preventives et Cliniques in Paris write.

The team studied the impact of overweight on fatal heart
attacks or strokes according to the presence or absence of
associated risk factors, such as high blood pressure and
diabetes, in more than 240,000 adults who had a standard health
checkup between 1972 and 1988 and were followed for an average
of 14 years.

Forty-two percent of the men and 21 percent of the women
were overweight and about 5 percent in each group were obese.
In both sexes, the rate of high blood pressure, diabetes, and
high cholesterol increased significantly with increasing
overweight status.

During follow-up, 2949 men and 929 women died of heart
attack or stroke.

Overweight subjects without associated risk factors did not
have an increased risk of heart attack or stroke death compared
with normal weight subjects.

However, men and women who were overweight and had high
blood pressure had about double the risk for heart attack or
stroke death relative to men and women who were overweight with
normal blood pressure.

In both men and women, being overweight and having diabetes
only or high cholesterol only did not increase the risk of
death from heart attack or stroke.

By contrast, in the presence of high blood pressure, the
risk of heart attack or stroke death “dramatically increased”
in overweight subjects with high cholesterol or diabetes.

High blood pressure was the most important factor
associated with increased risk of heart attack or stroke deaths
in overweight subjects, Benetos said in a statement. Therefore,
the best way to reduce risk is through “treatment that targets
both blood pressure and weight reduction.”

The finding, Dr. Frank B. Hu of the Harvard School of
Public Health added in a related editorial, “underscores the
importance of (high blood pressure) as a mechanism through
which obesity causes” heart attacks and strokes.

SOURCE: Hypertension, September 2005.