Archive for April, 2008

New Insight into the Origins of the Flu

There are several theories about the origins of the seasonal flu, but the actual source has been a long-standing mystery. Researchers are now reporting that flu strains appear to originate in east and southeast Asia. They then follow a highly predictable path to infect the rest of the world. Around six to nine months after Asia is infected, the flu migrates to Europe and North America. After another six to nine months, the final destination is South America where they disappear after causing one last outbreak.

Source: MedPage Today/Russell CA, et al “The global circulation of seasonal influenza A (H3N2) viruses” Science 2008; 320: 340-46.

Animals can be a therapeutic stress relief

A recent study found that contact with farm animals appeared to be therapeutic for patients with mental illness. These findings were similar to previous studies which have shown that animal-assisted therapy involving cats and dogs was associated with decreased stress and improved self-confidence, social competence, and overall quality of life.

via MedPage Today

Mental Decline Archives, 2005-2008

A mid-day nap can boost memory
In a recent study, researchers found that a 45-minute midday nap appeared to improve memory, but only when the information was already well consolidated. This study adds to the growing body of research that links improved memory with midday naps.
Source: Sleep, Feb 1, 2008

Memory testing scores improved significantly in a patient receiving deep brain stimulation.
Deep-brain stimulation sends an electrical current into a localized area of the brain and has been most commonly used in the motor cortex to improve motor function of patients with Parkinson’s disease and other movement disorders. Stimulation of the hypothalamus has also been used to treat cluster headaches and even aggressiveness. Researchers have had success in animals, using deep brain stimulation to influence feeding behavior. It was for this reason the researchers offered hypothalamic deep-brain stimulation to an obese 50-year-old man who had either failed or refused all other interventions.

As a result of the procedure, the man experienced only moderate benefits in appetite suppression with no long-term weight loss, yet unexpectedly, there was significant improvment in the patient’s memory on verbal and spatial associative tests. Although only a single-patient case study, this outcome suggests a potential new application for deep-brain stimulation in patients with disorders such as early Alzheimer’s disease. Annals of Neurology, January 2008

The aging brain can suffer deficits in attention, remembering, and planning even in the absence of Alzheimers
 
Eating fish, fruits, vegetables, and fats rich in omega-3 fatty acids (such as walnut oil) may help prevent dementia
French scientists have identified three dietary staples of seniors who avoid dementia: Eating fish at least once a week, fruits and vegetables (raw or cooked) daily, and using fats such as walnut oil, soy oil, or colza oil (related to canola oil). These diets were associated with less mental decline in seniors.
Sources: from MedPage Today/Neurology, November 2007

Delirium in elderly is common yet often preventable
Delirium is a new onset of a state of confusion in which symptoms develop fairly suddenly and can vary widely from fluctuating inattention and drowsiness to agitation and hallucinations. Many people do not realize that in the elderly, delerium is often the first symptom in the onset of an acute illness, such as a urinary tract infection, pneumonia, or possibly an adverse reaction to a medication. Elderly who are frail, malnourished, dehydrated or have a severe visual or hearing impairment tend to be at higher risk for delerium. Those who already have an underlying chronic dementia, such as Alzheimers, are especially prone to developing symptoms of delerium at the onset of any new or worsening medical condition.

Delerium and dementia are distinctly very different. Usually dementia has an insidious onset of long duration. The person has a lucid awareness level with normal attention, although it is less in severe cases. There is usually an absence of hallucinations in chronic dementia. On the other hand, delirium starts suddenly and hallucinations are frequent. The person has a reduced ability to focus, sustain, or shift attention. The symptoms fluctuate during 24 hours and are frequently worse in the evening. Delirium is often reversible if the underlying cause is removed or treated.

The onset of delerium can be frightening to the family and frequently challenging to health care professionals. A recent clinical review in the Brittish Medical Journal highlighted the fact that delerium can be misdiagnosed and mistreated. Several studies have found that more than half of all cases of delirium in older patients go unrecognized, often due to the perplexing overlap of frank dementia and temporary confusion. This oversight of course can be disasterous for both the patient and the family.

Risk factors for delirium include age over 65 years, frailty, dementia, hospitalization for infection or dehydration, visual impairment, deafness, renal impairment, or malnutrition, according to the medical researchers. They also point out that “delirium can be triggered by seemingly innocuous medications”  A number of medications can cause confusion in the elderly such as antihistamines, sleep medications, beta-blockers (for hypertension or heart disease), and H2 blockers (for stomach ulcer prevention).
Source: MedPage Today, April 2007

Curry appears promising for Alzheimer’s patients
Curcumin, a component of curry and turmeric, seems to help the immune system get rid of amyloid beta — the protein that builds up to form damaging plaques in the brains of Alzheimer’s patients. Previous research has also linked curry consumption to reduced Alzheimer’s risk, including one study that found that only 1 percent of elderly Indians developed the disease — a quarter of the rate seen in the United States. Curcumin is already known for its anti-inflammatory and antioxidant properties. Furthermore, a recent six-month study, carried out by researchers at Johns Hopkins University, found that daily doses of curcumin were associated with a nearly 60 percent lower risk for colon polyps, a known precursor to colon cancer.
Sources: US Dept of Health & Human Services/Journal of Alzheimer’s Disease October 2006

A Fatty Acid Found in Fish Linked to Lower Dementia Risk
In a recent study of 899 men and women, those with higher plasma levels of docosahexaenoic acid (DHA), had a 47% reduction in the risk of all-cause dementia and a 39% reduced risk of Alzheimer’s.

Plasma DHA must be obtained either by synthesis from dietary alpha-linolenic acid in the liver, or directly by consuming food rich in DHA, such as fatty fish or fish oil, or DHA supplements.

DHA is a fatty acid found in abundance in the brain, but has been shown to be decreased in the brain and plasma of patients with dementia.
Source: Archives of Neurology November 2006

A Mediterranean-style diet may help to fend off Alzheimer’s disease
Researchers have once again found evidence that people who followed a Mediterranean-style diet, light on red meat and rich in fruits, vegetables, and olive oil, had a decreased incidence of Alzheimer’s disease. Previous studies have found that this diet is also associated with lower risks for cardiovascular disease, several forms of cancer, and overall mortality. Furthermore, in another recent study, there was evidence that dietary supplements containing omega-3 fatty acids may reduce the rate of cognitive decline in people with the mildest form of Alzheimer’s disease. Omega-3 fatty acids are a main component of the Mediterranean diet.
Sources: MedPage Today/Archives of Neurology October 2006

Long-term lead exposure causes mental impairment in adults
A recent study has found that lifetime exposure to lead can cause problems with learning, memory, and visual-motor tasks in older adults. The severe adverse health effects of exposure in children have long been known. This study suggests that cumulative exposure to lead among adults is also associated with declines in cognitive function. Most lead has been removed from common environmental sources, but exposure is still possible from sources such as paint in older houses. Shih RA et al. “Environmental lead exposure and cognitive function in community-dwelling older adults.” Neurology, September 2006

Cognitive decline linked to diets high in bad fats and dietary copper
In a recently published study of 3,718 participants, ages 65 and older, a diet high in saturated fats and trans fats along with a high intake of dietary copper was associated with an accelerated decline in thinking, learning, and memory. Study participants who consumed the most fats in conjunction with the most copper experienced the most cognitive decline which was equivalent to an age gain of 19 years. Copper intake by itself was not associated with mental decline however.

In this study, cognitive scores declined on average by 4.2 standardized units per year in all participants as they grew older. Archives of Neurology, August 2006

Trans-fats, partially hydrogenated fats, are found in deep-fried foods, bakery products, packaged snack food, margarines, and crackers. It has been well established that consumption of these foods significantly raises levels of LDL (bad) cholesterol, reduces HDL (good) cholesterol, and increases triglyceride levels which increases the risk of coronary heart disease (CHD).(1)

Saturated fat is the main dietary cause of high blood cholesterol. The American Heart Association recommends that you limit your saturated fat intake to 7–10 percent of total calories (or less) each day. Saturated fat is found mostly in foods from animals, such as beef, beef fat, veal, lamb, pork, lard, poultry fat, butter, cream, milk, cheeses and other dairy products made from whole milk. Saturated fats can also be found in some plants, such as in coconut oil, palm oil and palm kernel oil (often called tropical oils), and cocoa butter.

Foods with the highest copper levels include organ meats, such as liver, and shellfish. Drinking water delivered through copper pipes may also add trace amounts of the metal. The recommended dietary allowance of copper for adults is 0.9 mg/d. The finding of accelerated cognitive decline among persons whose diets were high in copper and saturated and trans fats must be viewed with caution, the researchers warned however. In fact, previous supporting evidence on this topic is limited and further investigation is warranted.

A Tool to Calculate Dementia Risk
Swedish investigators have recently found a simple way, to calculate a middle-age person’s eventual dementia risk, on a scale of one to 15.

For people younger than 47, add 0 points to the risk score; for those 47 to 53, add three points; for those older than 53, add four points.

For people with more than 10 years of education add 0 points; for those with seven to nine years of education add 2 points; for 0 to six years of education, add three points.

For men add a point; for women add 0 points.

For a systolic blood pressure greater than 140 mm Hg, add two points to the score; for blood pressure less than 140 mm Hg, add 0 points.

For a body mass index of 30 mg/m2 or greater add two points to the score; for a body mass index less than 30 mg/m2, add 0 points. click here to calculate your BMI.

For a total serum cholesterol score 251 mg/dL or higher, add two points; for those having ever had less than 251 mg/dl, add 0 points.

For those who exercise for 30 minutes or longer at least twice a week, add 0 points; for those who are inactive add one point.

Results–People with scores of:

  • 6-7 have a 1.9% risk of dementia in the next two decades.
  • 8-9 have a 4.2% risk of dementia.
  • 10-11 have a 7.4% risk of dementia.
  • 12-15 have a 16.4% risk of dementia in the next 20 years.

This dementia risk tool is still under study and is being further refined by the researchers from the International Conference on Alzheimer’s Disease and Related Disorders 10th meeting Abstract P1-218: “THE DEMENTIA RISK SCORE — A PRACTICAL TOOL TO PREDICT DEMENTIA RISK IN 20 YEARS AMONG MIDDLE AGED PERSONS” July 17, 2006

Ditropan XL linked with significant memory deterioration
Ditropan XL has been widely used in the treatment for symptoms of overactive bladder for many years. Urinary dysfunction such as urge urinary incontinence, urgency and frequency can be diminished by Ditropan. Recent data from a clinical study looking at the effects of two prescription medications used to treat overactive bladder showed that treatment with Enablex did not result in impaired memory function in healthy adults age 60 and older. In contrast, treatment with Ditropan XL®(i) (oxybutynin extended-release or ER) caused significant memory deterioration. Furthermore, the individuals receiving Ditropan XL failed to notice the change in their memory function. 2006 Annual Meeting of the American Urological Association.
May 2006

Can Diet Protect Memory? 
In a study of 70 beagles, fed a diet rich in antioxidants over several years,  the dogs were found to be able to perform tasks — and learn new tricks — far better than fellow canines fed a normal diet. Moreover, MRI scans later revealed structural changes in the brains of the dogs on the antioxidant diet, most notably a decrease in the buildup of amyloid plaque. The researchers concluded that these findings indicate the brain has a capacity to recover some age-related loss of cognitive function.
Source: National Institute on Aging of the National Institutes of Health. 

 
Your brain needs exercise too
According to a recent study, people who had more mentally stimulating jobs during their 30’s and 40’s were less likely to develop Alzheimer’s later in life. This study from Case Western Reserve and University Hospital of Cleveland, revealed findings consistent with earlier studies which found that people who were free of Alzheimer’s disease in later life were more likely to have engaged in mentally stimulating leisure activities when they were younger. These activities included playing chess, reading books, playing a musical instrument, or learning a foreign language. Other lifestyle factors influencing the risk of development of Alzheimer’s include diet and physical activity. It is important to note that there is a genetic influence in the development of the disease as well.
Source: Neurology/Case Western Reserve/Univ Hosp of Cleveland, August 2005

 

Grade school intervention makes a difference in childhood obesity

A recent study found that educating and improving the eating and snacking choices in grade schools cut the rate at which kids become overweight in half.

via Foster GD, et al “A policy-based school intervention to prevent overweight and obesity” Pediatrics 2008; 121: 794-802.

The Best Type of Exercise that Generates the Least Force on the Knee

Biking is the best exercise for those who have knee problems or have had a total knee replacementBiking is the exercise that produces the least impact on the knee, and hence the best lifetime exercise for those who have undergone a total knee replacement, according to orthopedic researchers from Scripps Clinic in La Jolla, Calif. 

Biking is also a good exercise for strenthening the muscles that support the knee. 

Specifically, the findings from their study revealed the following impact on the knee:

  • Biking = 1.3 times the person’s body weight.
  • Treadmill = 2.05 times the body weight.
  • Walking on level ground = 2.6 times the body weight.
  • Tennis = 3.1 to 3.8 times the body weight, with serving producing the highest impact. Doubles tennis, instead of singles is often recommended to patients who have undergone total knee replacement (TKR), as it is less stressful to the knee.
  • Golf swings = 4.5 times body weight on the forward knee and 3.2 times body weight in the opposite knee. The researchers noted however that the impact from a golf swing occurred in an instant, while the forces produced by jogging are constant, which is worse. Golfers, who have previously undergone TKR, might want to consider consulting with a pro to modify the swing so that less force is exerted on the knee.
  • Jogging = 4.3 times body weight. Because of this repeated impact on the knee, it is advisable for people who’ve undergone knee replacement to give up jogging altogether and switch to another form of exercise.

SOURCE: American Academy of Orthopaedic Surgeon’s annual meeting April 2008