EMBARGOED FOR RELEASE UNTIL 4 PM ET, September 09, 2002
Cognitive Decline After Cardiac Valve Replacement Not a Given
St. Paul, Minn. -
A new study challenges previous findings that patients undergoing elective coronary bypass grafting (CABG), or valve replacement, experience long-term cognitive decline. That''s not always the case, according to the study published in September 10 issue of Neurology, the scientific journal of the American Academy of Neurology. The study compared the cognitive abilities of 52 patients prior to their CABG surgery and five years after. None of the patients showed clinically significant cognitive decline (defined as a decline of 1 standard deviation or more in at least two of the seven-part Wilcoxon tests administered). Other studies have reported late cognitive decline after CABG, however, none of these long-term follow-up studies included a control group like this one conducted at a hospital in Würzburg, Germany. According to neurologist Wolfgang Müllges, MD, the study author, "No individual patient showed a global decline at follow-up as compared to baseline. Seven patients (13 percent) had worse results in one single test." The researchers also compared follow-up data with data obtained at discharge. Even then, only four patients (8 percent) showed a standard deviation of more than 1 percent in two of the tests. Sixteen patients (31 percent) had lower follow-up test scores in only one of the tests, and 46 (88 percent) had better results in at least one test. The patients in this study may have had better outcomes through general medical care and by reducing vascular risk factors following their CAGB, said Müllges. "Many of the individuals had stopped smoking, many were prescribed statins, and many took steps to control their diabetes and hypertension," said Müllges. A shortcoming of the study was a lack of data or incomplete data from a portion of the 92 original members of the patient group which may have introduced a bias toward a better outcome. Müllges said neurologists work with their patients to provide care that reduces vascular risk for myocardial infarction, stroke and vascular dementia and contributes to a better quality of life for the growing elderly population. "Treatment of cardiac patients means more than surgery," he said.