In the first study to directly examine the
effects of b-blockers on surgical patients with chronic
obstructive pulmonary disease (COPD), researchers have found that, contrary to
previous thought, b-blockers significantly reduce mortality in
“Patients with COPD frequently have
unrecognized, atherosclerotic disease. This is also a major cause for late
morbidity and mortality,” said principle investigator Don Poldermans, M.D.,
Ph.D., of the Erasmus Medical Center in Rotterdam,
The results were published in the first issue
for October of the American Journal of
Respiratory and Critical Care Medicine, published by the American Thoracic
Clinical trials on the benefits of using
preoperative b-blockers to lower the risk of cardiovascular
events in patients undergoing noncardiac surgery have yielded inconsistent
results. Recent guidelines from the American Heart Association, however,
recommend b-blockers before noncardiac surgery for
patients who are at high risk for or who have known cardiovascular disease.
But patients with COPD, who have an increased
risk of cardiovascular disease, often do not receive preoperative b-blockers because of concerns that the drugs
will aggravate bronchospasm and worsen their airway obstruction. Moreover, the
benefits of b-blockers have not been examined in a
population of patients with COPD undergoing noncardiac
To determine the effect of b-blockers on COPD patients undergoing
vascular surgery, the researchers evaluated the mortality outcomes of more than
3,000 consecutive patients who underwent vascular surgery at the Erasmus Medical Center in Rotterdam between 1990 and 2006. They
specifically looked at the effect of a low dose of b-blockers (less than 25 percent maximum
recommended therapeutic dose) versus an “intensified” dosage (more than 25
percent maximum recommended therapeutic dose).
Of the 3,371 patients evaluated, 31
percent—more than 1000—received cardio-selective b-blockers at their initial hospitalization.
There was no apparent clinical differences between the patients with COPD— 39
percent of the entire study sample— and those without in terms of the likelihood
of them receiving b-blockers.
They found that cardio-selective b-blockers were independently associated with
reduced 30-day mortality in both patients with and without COPD. In the 30 days
after surgery, COPD patients did not receive b-blockers were twice as likely to die as
those who did (eight percent versus four percent.) Over the long term, a similar
trend, though not statistically significant, emerged. During the follow-up
period, 40 percent of COPD patients on b-blockers died, whereas 67 percent who were
not onb-blockers died.
“What was observed in the population, beta
blockers, especially, cardioselective beta blockers like bisoprolol are well
tolerated by COPD patients without inducing respiratory adverse effects. More
importantly, they improve outcome, by preventing late cardiac events, a major
cause for late morbidity and mortality,” said Dr.
They also found that in COPD patients, an
intensified dose, but not a low dose, of b-blockers was associated with reduced 30-day
mortality, but in the long term, both intensified and low dosages were
associated with similar reductions in mortality. In patients without COPD, both
low and intensified doses were associated with reduced mortality in 30-days but
in the long term, only the intensified dose was associated with a nonsignificant
trend in reduced mortality.
“We found that an intensified dosing regimen
appeared to be superior to low-dose therapy in terms of its impact on 30-day
mortality,” wrote Dr. Poldermans. “We [demonstrated] among a large group of
well-characterized patients with COPD…that b-blockers were safe and beneficial in
prolonging survival after major vascular surgery.”
“The indications of our findings are that a
high-dose might be preferred in the COPD population,” said Dr. Poldermans. “The
safety of cardioselective beta blockers in the COPD population will support
These findings demonstrate that carefully
selected patients with COPD can tolerate cardioselective beta-blockers without
experiencing respiratory complications. They also show that COPD patients may be
protected by b-blocker therapy from cardiovascular
complications of surgery, such as myocardial infarction. These findings need to
be put in context with the recent POISE (Perioperative Ischemic Evaluation)
study that demonstrated higher mortality among general populations of patients –
those with and without COPD – treated with preoperative b-blockers.
Dr. John E.
Heffner, past president of ATS and Garnjobst Chair at
Portland Medical Center, observed that “the jury remains
out regarding the utility of preoperative b-blockers for all patients at risk of
cardiovascular complications from noncardiac surgery. But this study suggests
that carefully selected patients with COPD, which is an extreme risk factor for
cardiovascular disease, at best may benefit but at least appear to tolerate
cardioselective b-blocker therapy. ”
News release from American Thoracic Society on October 1, 2008.