People with type 2 diabetes can expect to suffer from
fatal and non-fatal heart attacks, strokes and other cardiovascular
events about 15 years earlier than non-diabetics, a new
study shows.
"The rates are consistently higher," said lead
researcher Dr. Gillian Booth, an adjunct scientist at
the Institute of Clinical Evaluative Sciences in Toronto,
Canada.
Her team published its findings in the July 1 issue of
The Lancet.
It's long been known that type 2 diabetes increases
the risk for cardiovascular disease. In the study, Booth's
team studied the hospital and death records of nearly
9.5 million Canadians -- 379,000 of them with diabetes.
They hoped to determine how fast diabetes accelerates
an individual's progression to higher levels of risk
for cardiovascular disease.
The study found that men with type 2 diabetes entered
the cardiovascular "moderate-risk" category
at an average age of just under 39 years; for non-diabetic
men, that transition didn't typically occur until
more than 15 years later, at about age 55. Diabetic men
entered the "high-risk" category at just over
49 years of age, compared to 62 years for men without
diabetes, the researchers found.
The numbers for women were similar. Women with type 2
diabetes were classified as being at moderate risk for
heart disease at an average age of 46, compared to 62
years for non-diabetic women. And women with type 2 diabetes
entered the high-risk category at 56 years, compared to
just under 69 years of age for women without diabetes.
Perhaps the most striking numbers in the report involved
life expectancy. People with type 2 diabetes who were
also classified as being at moderate or high risk for
cardiovascular disease died an average of about 18 years
earlier than non-diabetics, the researchers found.
"This report is a call to action to physicians to
be aggressive in identifying patients and helping them
by telling them to be more physically active and watch
their weight," said Dr. V.S. Srinivas, an interventional
cardiologist at Montefiore Medical Center in New York
City.
The report "underscores the importance of identifying
diabetics early on," he said. Srinivas believes physicians
should be on the alert for persons at high risk of developing
type 2 diabetes and intervene early.
The study indicates that intervention at an early age
is a good strategy, Booth added.
"Under 40, people with diabetes seem to have a low-to-moderate
absolute risk of cardiovascular disease," she said.
"So at that age, it makes sense to individualize
treatment."
Srinivas said efforts at prevention could well start
even earlier, with educational programs for children on
the risks of diabetes.
The study covered only type 2 diabetes -- the kind that
generally begins in the adult years, often due to being
overweight and lack of exercise, Booth noted. An estimated
16 million to 18 million Americans have type 2 diabetes,
triple the number 30 years ago, due in large part to the
upsurge in obesity. People who are obese -- defined as
a body mass index (BMI) of 30 or greater -- have a five-fold
greater risk of type 2 diabetes than those with a normal
BMI of 25 or less, according to the National Institutes
of Health.
In type 2 diabetes, either the body does not produce
enough insulin or the cells ignore the insulin, a hormone
that converts blood sugar to energy for cells.
The study did not look at the effects of type 1 diabetes,
an autoimmune disease in which the insulin-producing beta
cells of the pancreas are destroyed. "We need to
do work about that," Booth said.
