New clues as to why some older people may be losing their memory

New research links 'silent strokes,' or small spots of dead brain cells, found in about one out of four older adults to memory loss in the elderly. The study is published in the January 3, 2012, print issue of Neurology, the medical journal of the American Academy of Neurology.

30 dec 2011--"The new aspect of this study of memory loss in the elderly is that it examines silent strokes and hippocampal shrinkage simultaneously," said study author Adam M. Brickman, PhD, of the Taub Institute for Research on Alzheimer's Disease and the Aging Brain at Columbia University Medical Center in New York.

For the study, a group of 658 people ages 65 and older and free of dementia were given MRI brain scans. Participants also underwent tests that measured their memory, language, speed at processing information and visual perception. A total of 174 of the participants had silent strokes.

The study found people with silent strokes scored somewhat worse on memory tests than those without silent strokes. This was true whether or not people had a small hippocampus, which is the memory center of the brain.

"Given that conditions like Alzheimer's disease are defined mainly by memory problems, our results may lead to further insight into what causes symptoms and the development of new interventions for prevention. Since silent strokes and the volume of the hippocampus appeared to be associated with memory loss separately in our study, our results also support stroke prevention as a means for staving off memory problems," said Brickman.

Provided by American Academy of Neurology

Poor Ischemic Stroke Outcomes Linked to Poor Nutrition

By Peggy Peck
SEOUL, South Korea, Jan. 15 -- Undernourished stroke patients are more likely to have complications and a poor outcome than those who are well nourished.
In a study of 131 acute ischemic stroke patients, those who were undernourished prior to the event were almost seven times more likely to have complications (P=0.04), reported Dong-Wha Kang, M.D., Ph.D., of the University of Ulsan in Seoul, and colleagues, in the January issue of the Archives of Neurology.
As expected, stroke severity as measured by the National Institutes of Health Stroke Scale (NIHSS) was also a significant predictor of poor outcome (OR: 1.21, 95% CI: 1.01 to 1.45; P=0.04), but the strongest predictor was poor nutrition. However the confidence intervals were wide (OR: 6.72, 95% CI: 1.09 to 41.56, P=0.04),
And when poor outcome was limited to patients who had a disability score (mRS) of 2 to 6 or 3 to 6, "undernutrition was not an independent predictor of poor outcome," a finding that the authors attributed to small sample size.
In an accompanying editorial, Neeraj Badjatia, M.D., and Mitchell Elkind, M.D., M.S., of Columbia University in New York, wrote that the study was the latest in a series of studies that have linked nutrition to stroke outcome.
"Providing adequate caloric support early in the course after ischemic stroke may now be seen as a therapeutic intervention used to minimize stroke severity, reduce complications, and favorably affect patient outcomes," they wrote.
The 131 acute ischemic stroke patients had a mean age of 65. Eighty-four were men and the median baseline NIHSS score was 4 (range 0 to 23), with only seven patients in the severe range (NIHSS score of 15 or higher).
Sixteen patients were considered undernourished at baseline, defined as weight loss of 10% or more in the three months prior to stroke, weight index less than 80%, albumin level less than 3.0 q/dL, transferring level less than 150 mg/dL, and prealbumin level of less than 10 mg/dL.
At one week post stroke, 26 patients were considered undernourished -- weight loss of 6% or more in the week following stroke plus biomarkers of undernourishment.
In general, older patients were more likely to be undernourished before stroke (P<0.001), as were patients with higher baseline NIHSS scores (P=0.04).
Age also predicted undernutrition in the week following stroke, as did absence of hypercholesterolemia (P=0.04), and enteral feeding (P=0.049) along with baseline undernutrition.
During the three-month follow-up period, recurrent stroke occurred in two patients (1.5%) and death occurred in four (3.1%). Two deaths were from respiratory failure, one from cancer, and one of unknown cause. Baseline and one-week undernutrition were not associated with recurrent stroke or death.
Multiple logistic regression analysis revealed that poor outcome, as defined by one-month mRS responder analysis, was associated with one-week undernutrition (OR: 4.49, 95% CI: 1.07 to 18.94, P=0.04) and one-week NIHSS score (OR: 1.76, 95% CI: 1.31 to 2.37, P<.001).
The authors cautioned that the study was limited by a number of factors including population, because it was limited to a single tertiary hospital in an Asian country.
Also the study eliminated a number of stroke patients and as a result the study population represented patients with relatively mild strokes.
The study was supported by the Korean Ministry of Health and Welfare and the Ministry of Science and Technology of Korea.
The authors disclosed no financial conflicts.
Primary source: Archives of NeurologySource reference:Yoo S-H et al "Undernutrition as a Predictor of Poor Clinical Outcomes in Acute Ischemic Stroke" Arch Neurol 2008; 65:39-43 Additional source: Archives of NeurologySource reference: Badjatia N and Elkin MSV "Nutritional Suport After Ischemic Stroke More Food for Thought" 2008; 65:15-16