TUESDAY, Feb. 23 (HealthDay News) -- Elderly people who have been hospitalized have an increased risk of cognitive decline.

That's the finding of U.S. researchers who analyzed data from 1994 through 2007 on 2,929 people, aged 65 and older, who did not have dementia at the start of the study. During an average follow-up of 6.1 years, 1,287 were hospitalized for a non-critical illness and 41 were hospitalized for a critical illness, while 1,601 of the participants were not hospitalized.

Among those hospitalized for one or more non-critical illnesses, there were 228 cases of dementia, and among those hospitalized with one or more critical illnesses, there were five cases of dementia. There were 146 cases of dementia reported among the participants who weren't hospitalized during the study period, the authors noted.

After adjusting for various factors, the researchers concluded that patients hospitalized for a non-critical illness were 40 percent more likely to develop dementia than those who weren't hospitalized. Seniors hospitalized with a critical illness also had a higher risk of dementia, but the result wasn't significant, possibly because of the small number of people in that group, the study authors explained.

"The mechanism of this association is uncertain," wrote Dr. William J. Ehlenbach, of the University of Washington, Seattle, and colleagues. "These results also could suggest that factors associated with acute illness, and to a greater degree with critical illness, may be causally related to cognitive decline."

There are a number of possible mechanisms through which critical illness could contribute to cognitive decline, including hypoxemia (decreased partial pressure of oxygen in blood), delirium, low blood pressure, glucose dysregulation, inflammation, and sedative and analgesic medications, the report indicated.

"Further studies are needed to better understand the factors associated with acute and critical illness that may contribute to cognitive impairment," the researchers concluded.

The study findings are published in the Feb. 24 issue of the Journal of the American Medical Association.

More information

The AGS Foundation for Health in Aging offers cognitive vitality tips for older adults  .

FRIDAY, Feb. 19 (HealthDay News) -- After retiring from her job as a Salvation Army pastor, Elizabeth Reed felt she still had more to offer.

So Reed, 74, signed up with Experience Corps, a program that teams elementary students in low-income schools with seniors who serve as tutors in reading and math.

Reed, who spends upwards of 20 hours a week at a school in Dorchester, Mass., says helping children discover the joy of curling up with a good book has not only given her renewed sense of purpose, but has helped her feel mentally sharper.

"I get a lot out of seeing the young people progress," Reed said. "In the beginning, they're sort of reluctant. They feel they aren't good enough readers and they don't want to do it. I like working with them, supporting them and telling them to never say 'can't.'"

Research is beginning to back up Reed's perceptions. A 2009 study by researchers from Washington University in St. Louis found children who received Experience Corps tutoring had much greater reading comprehension and ability to sound out words compared to kids who were not tutored.

And it's not only the kids who are reaping the benefits. A recent study found that among seniors, tutoring might help delay or even reverse some of the signs of aging in the brain.

After six months of tutoring, functional MRIs of the brains of eight Experience Corps volunteers showed improvements in regions of the brain involved in thinking and the ability to organize multiple tasks. Called "executive function," it's a skill that's crucial to maintaining independence in old age, said study author Michelle Carlson, an associate professor in the department of mental health at Johns Hopkins Bloomberg School of Public Health in Baltimore.

At the outset of the study, the women were considered at high risk of cognitive impairment because they were low income, had completed an average of 12 years of school (high school) and had low scores on a test of cognition.

"By engaging in this high-intensity volunteer service with children, seniors may actually be boosting their own executive function and ability to coordinate multiple tasks," Carlson said. "The next step is to think about if this kind of service may buffer them against risks for Alzheimer's disease."

The study was published recently in the Journal of Gerontology: Medical Sciences.

Experience Corps, launched in 1995, now includes 2,000 tutors aged 55 and up in 22 cities who are teaching over 20,000 students. Participating is no small commitment. Seniors go through a 40-hour training that includes brushing up on math skills, learning to choose age-appropriate books and learning to use a library's Dewey Decimal system. Seniors, who may receive a small stipend of $100 to $200 a month to cover their transportation costs, spend at least 15 hours a week in grades K-3 tutoring children either one-on-one or in small groups.

The fact that participating requires substantial effort, both mental and physical, on the part of the seniors may be one of the keys to its success, Carlson said.

There are plenty of studies that show staying physically active, socially active and taking part in activities that stimulate the mind can help forestall some age-related declines. Many studies suggest one of the best ways of going about this is volunteering.

For example, a study presented last year at the American Geriatrics Society annual meeting found that retirees over 65 who volunteered had less than half the risk of dying as retirees who didn't volunteer.

But many of the studies on volunteering and aging are based on surveys that ask seniors about how active they are in a given period. Researchers from Johns Hopkins are currently conducting lengthier studies that track Experience Corps participants over time to determine exactly what aspects of volunteering seem to be the most beneficial.

"Experience Corps is about more than just getting out and being social. Seniors are problem-solving and working with teachers. Many of them say it clears the cobwebs out," Carlson said. "They have a routine in which they have to get up and out in the morning, so there's a physical activity component as well."

Kesia Ferreira, a third-grader at a Dorchester elementary school, was matched with Elizabeth Reed as her tutor a few months ago. Kesia's parents' first languages are Portuguese and Creole. Kesia dreaded the thought that she might be laughed at if she missed a word while reading aloud.

Together, Kesia and Reed tackled a book called The Bravest Girls in the World. Not only is it now Kesia's favorite book, some of the confidence of the little girl in the book has rubbed off on Kesia.

"Miss Reed is nice. She's kind. She helps me to read and tells me what words mean if I don't understand them," Kesia said. "I don't worry anymore about reading out loud."

More information

Read more about volunteering at Experience Corps  .

MONDAY, Feb. 1 (HealthDay News) -- A blood test can predict rheumatoid arthritis long before a person notices symptoms, say Swedish researchers.

They identified several cytokines, cytokine-related factors and chemokines whose levels increase significantly as much as several years before the onset of rheumatoid arthritis (RA).

People who receive an early and accurate diagnosis of RA and immediately begin treatment are more likely to lead an active life and less likely to suffer joint damage that leads to joint replacement, according to the American College of Rheumatology.

In the study, the researchers analyzed blood samples taken from 86 people before the onset of RA symptoms, from 69 of the same people after RA symptoms began and from a group of 256 people who did not have the disease.

The blood samples were checked for levels of 30 cytokines, related factors and chemokines. The main difference detected between people who later developed RA and those who did not have it was the presence of Th1 cell-, Th2 cell-, and Treg cell-related cytokines. The main difference between people before and after development of RA was the presence of chemokines, stromal cell-derived cytokines and angiogenic-related markers, the study found.

The elevated concentrations of proinflammatory cytokines, cytokine-related factors and chemokines indicate immune system activation before any symptoms of RA-related joint problems, the researchers said.

The study appears in the February issue of Arthritis & Rheumatism.

More information

The American Academy of Family Physicians has more about rheumatoid arthritis  .

WEDNESDAY, Jan. 6 (HealthDay News) -- Targeting two different enzymes simultaneously may hold promise for treating people with Alzheimer's disease, researchers report.

This "cocktail" strategy, described in the Jan. 6 issue of Science Translational Medicine, outperformed a one-enzyme-at-a-time treatment and also avoided the troublesome side effects seen with that strategy, Johns Hopkins scientists say.

"This does give an idea that moderate reduction of both of these [enzymes] in combination could have an effective response and get rid of all the side effects," said Ian Murray, an assistant professor of neuroscience and experimental therapeutics at Texas A&M Health Science Center College of Medicine in College Station.

So far the results have only been seen in mice, although clinical trials could be on the horizon.

Most experts believe that Alzheimer's is caused by the overproduction of amyloid beta protein or amyloid plaque in the brain.

Two enzymes, beta-secretase and gamma-secretase, produce amyloid plaque by cleaving or breaking down the parent protein, known as amyloid precursor protein (APP).

"They work hand in hand, one after the other and act like scissors, cutting up this [APP] protein into smaller bits and smaller bits called amyloid peptide, which we think is the cause of Alzheimer's disease when it's abnormally accumulated in the brain," explained study senior author Philip C. Wong, a professor of pathology and of neuroscience at Johns Hopkins University School of Medicine in Baltimore.

"They both are required for generation of amyloid beta peptide," he added.

Researchers and pharmaceutical companies hope to figure out how to inhibit these enzymes as a way to treat Alzheimer's.

But beta secretase and gamma secretase have other jobs, too, which likely would be affected by any attempt to reduce their activity.

"Initially we knocked out each one individually and showed that if you reduce the activity you do have good efficacy in terms of reducing amyloid burden, but it also led to other problems," Wong said.

In this trial, the researchers tried a new approach: reducing levels of both enzymes at the same time in genetically altered mice. That worked.

"The combination of reducing both enzymes simultaneously will give you a better outcome in terms of reducing the amyloid and attenuating the learning and memory behavior you see in these animal models," Wong said. "Moreover, we did not see any evidence of side effects."

Compounds to inhibit these genes are nearing possible use in clinical trials, the authors stated.

"It does hold promise for future studies in human subjects," Murray said. But, no actual drugs were used in the study, only genetic alterations to mimic the desired effect of a future drug, he added.

Another potential obstacle is amyloid beta's recently discovered role in synaptic function, or connections and communication between neurons.

"Too much or too little amyloid beta is detrimental, so it seems that you have to have a balance," Murray pointed out.

And, "it has been suggested that reduction of amyloid beta at late stages in the disease may not have any benefit, as the neurological damage has already occurred," he added. "However, clinical trials with amyloid beta vaccination suggest that reduction of amyloid beta halts cognitive decline in this disease [so] there is promise for such therapy."

More information

Visit the Alzheimer's Association   for more on this condition.