Depression might not break your heart, but it could keep it from bouncing back after a heart attack.
A recent study has shown that while heart rate variability — an indicator of a healthy heart — is lowered in all patients following a heart attack, it might not recover in those with untreated depression.
Heart rate variability is the measure of changes in one’s heart rate. Previous studies have shown decreased heart rate variability is a predictor of death following a heart attack. It is also known that heart rate variability is lower in depressed people than in non-depressed people.
Researchers led by Dr. Alexander Glassman of Columbia University in New York randomly assigned 290 heart attack patients with major depression to receive inactive placebo pills or treatment with the antidepressant sertraline. Heart rate variability improved in patients who received sertraline but worsened in those who received placebos.
Glassman says that in non-depressed patients, heart rate variability recovers approximately half of its previous value over the months following a heart attack. In the current study, patients with untreated depression did not experience any heart rate recovery.
“Depressed people not only started out lower, but they didn’t recover (their heart rate variability) as much. As a matter of fact, on the average, they don’t recover at all,” Glassman says. “That makes them even more vulnerable to dying.”
Glassman says heart rate variability can be improved through exercise, which is generally recommended after a heart attack. “Rehab is good for everybody, (not just) if somebody has low heart rate variability.”