Thinner Brains Could Signal Alzheimer's, Study Suggests

New research suggests that the outer edges of the brain are thinner in older people who may be destined to develop Alzheimer's disease, but there's currently no way to use the information to help people fend off dementia.

Still, the findings could help researchers test Alzheimer's medications by allowing them to track the progression of the disease, said study co-author Dr. Brad Dickerson, an associate professor of neurology at Harvard Medical School.

Alzheimer's disease is the sixth leading cause of death in the United States, according to the Alzheimer's Association, and the number of deaths has risen in recent years. There's no cure for the disease.

In the new study, researchers focused on the thickness of the edges of the brain, known as the cortex. "We're looking at the parts of the cortex that are particularly vulnerable to Alzheimer's disease, parts that are important for memory, problem-solving skills and higher-language functions," Dickerson said.

Previous research found that several areas of the cortex were smaller in people with dementia from Alzheimer's. "It's like an orange that's shriveling. The thickness of the outer skin might get thinner as it dries out," Dickerson said.

In the new study, researchers examined the MRI brain scans of 159 people with an average age of 76; about half were men. Three years later, the participants took tests designed to measure how their brains were functioning.

The findings appear in the 21 December 2011 online issue of the Journal Neurology.

The 15 percent of participants with the thinnest brain areas performed the worst on the tests: About one in five of them experienced cognitive decline. They also showed increases in signs of abnormal spinal fluid, a possible sign of developing Alzheimer's disease.

"That suggests they may be developing symptoms," Dickerson said.

A lower number - 7 percent - of the participants in the middle range of brain thinness experienced cognitive decline. None of the people with the least thin brain areas developed problems.

So are the scans appropriate as tools to figure out whether patients are on the road to Alzheimer's?

Cost doesn't appear to be a major challenge at this point. It's not clear how much the MRI scans might cost at doctor's offices, Dickerson said. However, they're only a few hundred dollars each in the research world.

Also, many older people already receive MRI scans of the brain for other reasons, said Dr. Raj Shah, medical director of the Rush Memory Clinic, in Chicago.

But with no cure for Alzheimer's, the best use for the scans will be to help researchers figure out if medications work, Dickerson said.

Cathy Roe, an Assistant Professor of Neurology at the Knight Alzheimer's Disease Research Center at Washington University School of Medicine, in St. Louis, said the findings could have value down the line. "Right now, there is not much we can do to delay the progression of dementia," said Roe, who's familiar with the findings. "But once effective treatments are identified, this research could help to identify which patients should receive that treatment and when they should receive it."

(Source: HealthDayNews, 21 December 2011)

More information about the link between BMI and Alzheimer's

Two new studies find that people with a low BMI are at greater risk of mortality and those with early stage Alzheimer's have a lower BMI.

Article from the ABC News :

Low BMI Linked to Alzheimer's and Death After Surgery

Maintaining a low Body Mass Index, or BMI, has long been considered a healthy practice for the general population, but two new studies have suggested links between low BMI and serious health conditions.

The first study, published in the Journal Neurology found that older people in the earliest stages of Alzheimer's disease are more likely to have lower BMI.

"The earliest stages of Alzheimer's are associated with some metabolic dysfunction, as evidence with the differences in BMI," said Dr. Jeffrey Burns, lead author of the study and Director of the Alzheimer and Memory Program at University of Kansas Medical Center. "We saw the relationship between Alzheimer's markers with body composition with low BMI in people in the earliest stages of the disease, both in people with mild cognitive impairment and in people without functional problems."

While Burns said he does not have the evidence to support whether low BMI puts people at risk of cognitive impairment or cognitive impairment may contribute to lower BMI, he said it goes beyond simple changes in one's ability to remember to eat.

"It reflects there is a systemic response to an underlying problem," said Burns. "We think of Alzheimer's as classically a brain disease, but now there's evidence that there are measurable changes going on in the body."

BMI is a number calculated from a person's height and weight that is meant to indicate body fatness in most people. According to the Centers for Disease Control and Prevention, 18.5 and below is considered underweight. Normal weight ranges from 18.5 to 24.9. Overweight spans from 25 to 29.9 and obese is considered 30 and above.

Researchers analyzed more than 500 patients with Alzheimer's biomarkers through advanced brain imaging techniques and cerebrospinal fluid. The biomarkers are often present years before symptoms set in. Study participants included people without any memory problems and those with mild cognitive impairment.

While the link between later-life low body mass and Alzheimer's disease has been fairly established by previous research publications, William Thies, Chief Medical and Scientific Officer of the Alzheimer's Association, said this study appears to extend this relationship to the earliest stages of Alzheimer's pathology through the biomarker findings.

Interestingly, prior research has shown that middle-aged people who are overweight or obese (higher BMIs) are at greater risk of developing Alzheimer's disease.

"It appears that mid-life high BMI and later life lower BMI are both related to Alzheimer's disease," said Thies. "Perhaps the mid-life findings are due to exacerbation of vascular risk by high BMI. The later-life linkage between low BMI and Alzheimer's may come about as the result of the earliest changes of Alzheimer's disease and result in a lowering of appetite, among other things."

While Burns said they are currently conducting studies that look deeper into metabolic changes in the body and brain, Thies said further research on early-stage symptoms is expansive and expensive.

"Without more money being invested in basic Alzheimer's disease research studies, we will never know the real relationship between BMI, age, and Alzheimer's disease," said Thies. "We must see, and quite soon, a greater commitment to Alzheimer's disease research at the federal level, and from industry, and from the American public."

In the second study, low BMI was spotlighted as increasing risk of death within 30 days of surgery. The research, published in the Archives of Surgery, found that, of the nearly 190,000 patients included in the study, 1.7 percent of them died within 30 days of surgery. Deaths among patients with a BMI less than 23.1 were twice that of patients with a BMI of 35.3 or higher.

"Patients with low body mass index are at significantly higher risk of death with 30 days after following general and vascular surgical procedures," said Dr. George Stukenborg, Associate Professor of Public Health Sciences at University of Virginia's School of Medicine. "Low BMI should be taken into account as an important risk factor for risk of death within 30 days of the procedure."

Oddly, patients in the heavier BMI groups did not have "a statistically significant mortality risk," said Stukenborg.

Patients who underwent laparatomy, or a procedure involving a large incision through the abdominal wall, were at highest risk of death after surgery, compared with other operations.

Stukenborg said the research does not disclose why BMI is a risk factor for death, but experts say the higher amount of deaths could be among the frail and elderly, not the young, thin and healthy. Stukenborg said he and his colleagues plan to investigate reasons for the increased risk in upcoming studies.

(Source: By Mikaela Conley, ABC World News, 27 November 2011)

Some People With Alzheimer's Take Conflicting Drugs - Common medications might block action of dementia drugs like Aricept

Many Alzheimer's patients who take cholinesterase inhibitors to slow their brain disease also take drugs that counter the effects of those Alzheimer's medications, a new study says.

Clinical trials have shown that cholinesterase inhibitors such as Aricept (donepezil) have a modest impact on the functional and cognitive decline caused by Alzheimer's disease, noted the researchers at the Group Health Research Institute in Seattle.

"Cholinesterase inhibitors are today's primary therapy for slowing Alzheimer's disease," study leader Denise Boudreau said in an institute news release.

"Anticholinergic properties are often found in drugs commonly used to treat gastrointestinal disorders, allergies, urinary incontinence, depression and Parkinson's disease, and they can have negative effects on cognition and function in the elderly. There's concern that if someone is taking both types of drugs - cholinesterase inhibitors and anticholinergic medications - they will antagonize each other, and neither will work," she explained.

Common anticholinergic medications include Benadryl (diphenhydramine) and Ditropan (oxybutynin), which is prescribed for overactive bladders.

Boudreau and colleagues analyzed data from more than 5,600 patients aged 50 and older who had cholinesterase inhibitors prescribed to them for the first time between 2000 and 2007. Of those patients, 37 percent also took at least one anticholinergic drug and more than 11 percent took two or more anticholinergic drugs.

Among the patients who took both classes of drugs, dual use generally lasted three to four months, but one-quarter of the patients used both classes of drugs for more than a year.

The researchers also found that 23 percent of patients who received a new prescription for cholinesterase inhibitors were already using at least one anticholinergic drug, and 77 percent of those patients continued taking an anticholinergic drug after they began taking a cholinesterase inhibitor.

"It's reassuring that we did not observe an association between simultaneous use of the two types of drugs and increased risk of death or nursing home placement," Boudreau said in the release. "But concomitant use of these drugs is, at the very least, not optimal clinical practice."

The study was published online October 22, 2011 in the Journal of the American Geriatrics Society.

Alzheimer's patients often have multiple health problems, which may help explain why doctors might prescribe conflicting medications for these patients, the researchers said.

More information:
U.S. National Institute on Aging has more about Alzheimer's medications.
Alzheimer's Association => Learn more about Alzheimer's Medications

Source: Group Health Research Institute, News Release, October 25, 2011

Certain Senior Moments May Signal Mental Decline

Getting lost in familiar places, trouble following a group conversation are red flags, study finds.

Those "senior moments" that plague so many aging Baby Boomers may or may not be a sign of more serious problems down the line.

New research finds that losing your train of thought or forgetting where you placed your keys may be a fairly benign - albeit annoying - sign of age. But having trouble remembering what happened a few minutes ago, or getting lost in familiar places, may be more serious.

The information, published in the September issue of the Journal of the American Geriatrics Society, should help primary care physicians sort out the mundane from the more troublesome when they see elderly patients.

"They should be asking their patients if they have any complaints (about memory or thinking skills)," said study lead author Rebecca Amariglio, a neuropsychologist with Brigham and Women's Hospital and Harvard Medical School in Boston. "When you're getting old, it's common to ignore these complaints."

President Obama's Affordable Care Act includes a provision for screening for these types of problems, called cognitive problems, at a person's annual physical exam.

So researchers are trying to find simple ways to sort out which patients can go home (relatively) reassured, and which might need further testing for Alzheimer's disease or another form of dementia.

For this study, researchers quizzed almost 17,000 women, average age about 74, over the telephone about their own recollections of memory lapses. The investigators then correlated this data with how the women scored on standard cognitive tests, including delayed recall of sets of words and numbers, also administered over the telephone.

The researchers used a set of questions - seven in all - which asked the participants if they had recently experienced a change in their ability to remember things, whether they had trouble remembering a short list of items (such as a shopping list), whether they had trouble remembering recent events, and whether they had trouble remembering things from one second to the next.

The women were also asked whether they had difficulty following spoken or written instructions, whether they had more trouble than usual following a group conversation or TV program due to memory problems, or whether they had trouble finding their way around familiar streets.

"Getting lost," in particular, was highly associated with cognitive impairment. Women who reported they had gotten lost in familiar neighborhoods tended to score significantly lower on cognitive tests similar to those used to detect signs of Alzheimer's. Having trouble keeping up with a group conversation and difficulty following instructions were also strongly associated - though not as highly - with cognitive impairment.

On the other hand, forgetting things from one moment to the next was not associated with any decline in measure of cognitive function. But the more complaints a woman had, the more likely she was to score poorly on the test administered by investigators. Each additional complaint was associated with a 20 percent increase in cognitive impairment. (The complaint of forgetting one moment to the next had a score of zero since it was not associated with impairment.)

The authors noted that the participants were all women and mostly white, however, which means that the findings may not be generalizable to other populations.

Another expert pointed out other limitations of the study.

The "senior moments" reported by the study participants were only related to how well they did on the telephone tests, not to whether or not the person had actual dementia, according to Mary Sano, professor of psychiatry and director of the Alzheimer's Disease Research Center at Mount Sinai School of Medicine in New York City.

"This may overstate the problem, which also is not a good thing," she said, adding that the study does not trace the source of any problems it uncovered.

"The next step going forward would be to develop specific questions to ask [and] to see if this relates to dementia," Amariglio said.

For now, simple questions don't portend "what the future holds," she added. But answers may indicate that follow-up is warranted.

"It's one little extra red flag that can maybe direct decisions," Amariglio said.

More information

For more information about stages of Alzheimer's, visit the Alzheimer's Association.

Sources: Rebecca Amariglio, Ph.D., neuropsychologist, Brigham and Women's Hospital and Harvard Medical School, Boston; Mary Sano, Ph.D., professor, psychiatry, and director, Alzheimer's Disease Research Center, Mount Sinai School of Medicine, New York City; September 2011 Journal of the American Geriatrics Society.