Study says loss of smell may help sniff out Alzheimer's disease

A small pilot study of patients displaying signs of cognitive decline found that peanut butter can help identify those with Alzheimer’s disease, which is often accompanied by a loss of smell.

The results indicate that loss in sense of smell may help in diagnosing Alzheimer's. Loss of smell can be detected long before classic clinical symptoms, and it may not only be an early warning sign of Alzheimer's, but it is also an indicator for Parkinson’s disease and some other neurological disorders, writes Richard Doty of the Smell and Taste Center at the University of Pennsylvania’s Perelman School of Medicine.

Alzheimer’s is an irreversible, progressive brain disease that slowly destroys memory and thinking skills, but early diagnosis is usually beneficial. It can tell people whether their symptoms are from Alzheimer’s or another cause, such as stroke, tumor, Parkinson’s or other conditions that may be treatable. In most people with Alzheimer’s, symptoms first appear after age 60, and estimates suggest that as many as 5.1 million Americans may have it, says the National Institute on Aging.

The study of 96 patients was conducted by the McKnight Brain Institute Center for Smell and Taste at the University of Florida. Eighteen of the patients had probable Alzheimer's, 24 had a mild cognitive impairment, 26 had some form of dementia, and the other 26 patients were used as a control group.

The researchers measured the distance from the nose at which patients, whose eyes were closed, could smell a tablespoon of peanut butter one nostril at a time. Early-stage Alzheimer's patients had different smell sensitivity between the right and left nostrils, with the left regularly being more severely impaired. The other patients displayed no such difference in smell sensitivity, says the study, published in the Journal of Neurological Sciences.

“This non-invasive and inexpensive left–right nostril odor detection test appears to be a sensitive and specific test for probable Alzheimer's disease,” graduate student Jennifer Stamp, one of the researchers, told Jef Akst of The Scientist magazine. More research is needed to validate the approach, she added: “We plan to study patients with mild cognitive impairment to see if this test might be used to predict which patients are going to get Alzheimer’s disease.”

Click here to read Doty's “Smell and the Degenerating Brain” for a deeper look at the link between smell and neurodegeneration. Click here for more information about Alzheimer's disease.

Caregivers of Alzheimer's patients suffer, sometimes to death

It's common to hear about diseases like Alzheimer's drastically affecting the lives of those who have it, often causing severe struggles and hardships. What you may not hear much about is how caregivers of people with Alzheimer's can also suffer deeply and greatly.

Jim Crabtree was actually relieved to find out that his wife and mother had been shot and killed by his father who then shot and killed himself, Linda Carroll of NBC News reports. (Today show photo: Crabtree with his wife, Rita)

"Crabtree had been struggling" to care for his 62-year old wife, who had been diagnosed with Alzheimer's six years before, and his elderly parents: a father with dementia and a mother with crippling arthritis.

Crabtree said he felt stretched thin with the responsibility of caring for his family and that by killing them, his father actually got rid of the burdens they caused him all at once, Carroll reports.

"Although rare, there are other murder-suicide cases involving caregivers and their charges. It’s a sign of how stressful the job is," Linda Ercoli, director of geriatric psychology at the Semel Institute at the University of California, Los Angeles said in the story.

The Alzheimer's Association has created a test for caregivers to check their stress levels. 

Carroll describes how caregivers' emotions can range from helplessness to anger when they don't understand that certain annoying behaviors by their ill patients could be symptoms of the disease. Because of high emotions that can arise in a home with Alzheimer's patients, Ercoli explains that violence isn't uncommon. Studies have found that 5 percent of caregivers have been violent with their patients and 16 percent of patients have been violent with their caregivers.

Caregivers at first get a certain satisfaction from taking care of others, but as the disease progresses, they tend to suffer from deep depression, anxiety or other disorders, Ercoli explains. Also, Carroll adds, caregivers sometimes face the risk of becoming physically sick themselves. 

Experts say that caregivers should reach out more to each other for support. “People don’t say, ‘I survived Alzheimer’s’,” Crabtree said. “We are the survivors. I survived caregiving.”

National effort to combat Alzheimer's disease begins; as research continues, there are preventive steps you can take

Country singer Glen Campbell, who has Alzheimer's disease,
stands with wife Kim during a national conference Tuesday.
Associated Press photo by Charles Dharapak.

With numbers expected to jump to 16 million Americans by 2050, research is being conducted in earnest to find a way to ward off Alzheimer's disease.

One plan of attack is testing therapies before people show symptoms of memory loss, since the disease starts attacking the brain at least 10 years before memory problems appear. An international study will see if an experimental drug can halt the disease in "people who appear healthy but are genetically destined to get a type of Alzheimer's that runs in the family," reports Lauran Neergaard for The Associated Press. In another study, researchers will see if a nasal spray that shoots insulin to the brain can help patients with early memory problems.

Part of the challenge in combatting the disease is researchers are still not sure what causes it. "The chief suspects are a sticky gunk called bata-amyloid, which makes up the disease's hallmark brain plaques, and tangles of a protein named tau that clogs up dying brain cells. One theory: "Amyloid may kick off the disease while tau speeds up the brain destruction," Neergaard reports.

Given the expected increase in the number of people with Alzheimer's, the Obama administration has adopted a national strategy to fight the disease, part of which is a website that is a "one-stop shop for families" to offer information about dementia and links to community resources. Today, there are 5.4 Americans with Alzheimer's or related dementias.

There are steps people can take to protect their brains from the disease, including intellectual and social stimulation to help build "cognitive reserve." Doing crossword puzzles, for example, can help. So can physical activity. "Any time your heart is healthier, your brain is healthier," said Dr. Elizabeth head of the University of Kentucky. Diet is another consideration, since foods that are heart healthy are brain healthy, including omega-3 fatty acids found in fish. (Read more)

Doctors use telemedicine to help patients with dementia, Alzheimer's

Following a nationwide trend, Kentucky doctors are turning to telemedicine to help patients with memory problems such as those associated with Alzheimer's disease and dementia, reports Allison Elliott with the University of Kentucky.

"State-of-the-art memory evaluations should not be limited to persons that are able tom ake the often long and arduous trip to Lexington," said Dr. Greg Jicha, neurologist at UK's Sanders-Brown Center on Aging. "Taking advantage of Internet technologists to bring expert care into even the smallest of rural communities is a blessing for many families across Kentucky that simply cannot bring a loved one with dementia to Lexington.

Several times a month, physicians with the Sanders-Brown Center will connect to patients in clinics throughout the state. Participating clinics include Harlan Appalachian Regional Health; the Hazard Center for Rural Health; T.J. Sampson Hospital in Glasgow; Trover Clinic in Madisonville; Western Baptist Hospital in Paducah; Owensboro Medical Center; and St. Claire Regional Medical Center in Morehead. (Read more)