According to a report in the August issue of Archives of Neurology, one of the JAMA/Archives journals, older patients with lower rates of left ventricular ejection fraction (measurement of heart pumping efficiency of the left ventricle with each contraction) appear more likely to have a significantly reduced verbal memory function compared with patients of a younger age.
According to background information of the article, researchers began studying the association of heart failure with cognitive decline 30 years ago and discovered that thirty to eighty percent of patients with heart failure may experience some cognitive deficits. The research revealed some inconsistent results between the correlation of cognitive impairment with decreased left ventricular ejection fraction (EF), a measurement of the severity of heart failure.
The authors state,
“Conflicting evidence about the association of EF with cognitive function suggests a complex relationship between patient variables and the cardiovascular factors that influence cognition.”
Between September 2006 and September 2008, Joanne R. Festa, Ph.D., from St. Luke’s – Roosevelt Hospital Center, New York, and her fellow researchers conducted a cross-sectional study to evaluate the relationship between age, EF and memory among patients with heart failure. All participants in the study consisted of adult patients with heart failure who underwent neurocognitive assessment during their assessment for a potential heart transplantation candidacy. The study evaluated participant’s verbal and visual memory, attention, executive functioning and self-reported depressive symptoms. Investigators recorded the medical history, current medications, demographic information, EF and heart failure cause of each participant.
The EF was measured by Echocardiography, categorized into 30%, less than 30% or higher than 30%. Researchers split the participants age groups into aged 45 years or younger, 46 to 55 years, 56 to 62 years and 63 years or older.
The final analysis of the study included a total of 207 participants with and 38 patients who had an EF of 30 or higher and 169 patients with an EF of less than 30. Research revealed, that EF levels in patients younger than 63 years of age maintained a stable memory function, while a significant connection to reduced memory performance was demonstrated in older patients when their EF was less than 30%.
The analysis revealed, that the highest association with low EF was verbal delayed recall and recognition. The investigators commented,
“In summary, an interaction exists between the age and EF such that older patients with low EF had significantly reduced memory, particularly verbal delayed recall and recognition. However, the association of low EF with “memory in these patients is not entirely explained by EF.”
The authors recommend for more studies to be conducted to research into additional mechanisms of cognitive dysfunction in patients with heart failure.
Written by Petra Rattue