By Megan Rauscher
WESTPORT, CT (Reuters Health) – Mood has a powerful influence on prognosis after acute myocardial infarction (MI), according to findings reported in the August 15th issue of the American Journal of Cardiology. Investigators found that patients who are even mildly depressed after a heart attack are at significantly increased risk of death.
Dr. David E. Bush and a team from Johns Hopkins University in Baltimore analyzed depressive symptoms in 285 patients who survived an acute MI. The overall mortality rate at 4 months was 6.7%.
In comments to Reuters Health, Dr. Bush said his team was "most surprised" to find that extremely low levels of depressive symptoms affected prognosis. "It only took trivial levels of depressive symptoms to increase the mortality risk after a heart attack," he said.
Patients with a Beck Depression Inventory (BDI) score of 4 to 5, which is generally not thought to be clinically significant, had post-MI mortality rates that were 5 times as high as those with BDI scores of less than 4, Dr. Bush said.
Patients with BDI scores in the 6 to 9 range, still below the clinically significant range, had mortality rates 7 to 8 times higher than those with scores of less than 4. Patients with BDI scores of 10 and higher, the generally accepted level of mild to moderate depression, had mortality rates that were 8 to 10 times higher than those scoring less than 4.
These findings point to a dose-response relationship that begins "at very low levels of depressive symptoms, in ranges that would not have previously been considered significant," Dr. Bush said.
"We do not yet know…the best way to address this increased risk in these patients," Dr. Bush said. "It is not yet known whether antidepressants will substantially lower the increased risk. However, since depression post-MI is associated with substantially higher risk, these patients should be identified so that they may be monitored more closely and encouraged to follow treatment recommendations," he added.
Am J Cardiol 2001;88:337-341.