Diabetes appears to
increase risk of death for patients with acute
coronary syndromes
Newswise — Individuals with
diabetes and acute coronary syndromes (ACS) such
as a heart attack or unstable angina have an
increased risk of death at 30 days and one year
after ACS, compared with ACS patients without
diabetes, according to a study in the August 15
issue of JAMA.
“The presence of elevated
blood glucose levels, diabetes mellitus, or both
contributes to more than 3 million
cardiovascular deaths worldwide each year. With
the increase in obesity, insulin resistance, and
the metabolic syndrome, the worldwide prevalence
of diabetes is expected to double by the year
2030,” the authors write. They add that more
than 1.5 million adults in the U.S. were newly
diagnosed with diabetes in 2005, and nearly 65
percent of individuals with diabetes die from
cardiovascular disease in the U.S., establishing
it as the leading cause of death among this
growing segment of the population. The effect of
diabetes on the risk of death following ACS is
uncertain.
Sean M. Donahoe, M.D., of
Brigham and Women’s Hospital and Harvard Medical
School, Boston, and colleagues evaluated the
independent effect of diabetes on risk of death
following ACS at 30 days and 1 year using a
large clinical trial database that included ACS.
The study consisted of an analysis of patients
with diabetes enrolled in randomized controlled
trials that evaluated ACS therapies. Patients
with ACS in 11 independent Thrombolysis in
Myocardial Infarction (TIMI) Study Group
clinical trials from 1997 to 2006 were pooled,
including 62,036 patients (46,577 with
ST-segment elevation myocardial infarction [STEMI;
a certain pattern on an electrocardiogram
following a heart attack] and 15,459 with
unstable angina/non–STEMI [UA/NSTEMI]), of whom
10,613 (17.1 percent) had diabetes.
The researchers found that
the rate of death was significantly higher among
patients with diabetes than among patients
without diabetes at 30 days following either UA/NSTEMI
(2.1 percent vs. 1.1 percent) or STEMI (8.5
percent vs. 5.4 percent). After adjusting for
baseline characteristics and features and
management of the ACS event, diabetes was
independently associated with a nearly 80
percent increased risk of death at 30-days after
UA/NSTEMI, and 40 percent increased risk of
death at 30-days after STEMI.
At 1 year, diabetes
remained a significant independent factor
associated with all-cause death for patients
presenting with UA/NSTEMI (65 percent increased
risk of death) or STEMI (22 percent increased
risk of death). By 1 year following ACS,
patients with diabetes presenting with UA/NSTEMI
had a risk of death that approached patients
without diabetes presenting with STEMI (7.2
percent vs. 8.1 percent).
“Despite modern therapies for
ACS, diabetes conferred a significant
independent excess mortality risk at 30 days and
1 year following ACS. Current strategies are
insufficient to ameliorate the adverse impact of
diabetes. Given the increasing burden of
cardiovascular disease attributable to diabetes
worldwide, our study highlights the need for a
major research effort to identify aggressive new
strategies to manage unstable ischemic heart
disease among this high-risk population,” the
authors conclude.
