(dailyRx News) Older coronary artery disease patients receiving cardiac catheterization who remain chronically depressed appear to be at a significantly increased risk of suffering from cognitive decline.
Though researchers found high rates of depression in older patients with coronary artery disease, they are not certain what factors increase the risk of cognitive decline.
Elizabeth A. Freiheit., of the University of Calgary in Canada, found that depression during the first year following heart interventions also was a significant factor for a decline in cognitive performance.
Investigators studied 350 patients over the age of 60 receiving cardiac catheterization for the first time. Many of those patients subsequently had coronary artery bypass surgery, angioplasty to open blocked arteries or other medical therapy.
Researchers examined symptoms of depression within 30 months of the procedures and also studied whether any associations were influenced by the presence of the apolipoprotein E (APOE) ε4 allele, believed to be a genetic risk factor for Alzheimer's disease.
They discovered that patients with persistent depression showed significantly greater cognitive decline 30 months after their heart procedure. Patients exhibited difficulties with attention, memory, global cognition and verbal fluency.
However, chronic symptoms during the first year also were significantly linked to cognitive decline 12 months to 30 months later.
Patients with APOE ε4 allele also were more likely to experience cognitive declines in global function and verbal fluency. Researchers suspect those with the gene were more likely to suffer larger brain declines.
"Consequently, a one-time assessment of depressive symptoms may be inadequate for detecting those at risk of longer-term adverse cognitive and functional outcomes," Freiheit and her colleagues wrote. "These findings illustrate the need for longer-term monitoring of depressive symptom severity and change by clinicians and other caregivers."
The research was published in the March issue of Archives of General Psychiatry.