How you think about your health can have powerful impacts on how you experience your health. In a recent study with a group of cardiac patients, how people thought about their illness (termed “illness cognitions”) was found to have a direct impact on how people experience health and emotional wellbeing [1]. These illness cognitions also affected health indirectly by influencing the types of behaviours people were engaged in to cope with cardiac problems. This study brings to our attention the relevance of psychology in relation to medical illnesses.
Scientists Find New Form of Prion Disease that Damages Brain Arteries
March 9, 2010 | by
National Institutes of Health (NIH) scientists investigating how prion diseases destroy the brain have observed a new form of the disease in mice that does not cause the sponge-like brain deterioration typically seen in prion diseases. Instead, it resembles a form of human Alzheimer’s disease, cerebral amyloid angiopathy, that damages brain arteries.
NIH Newsbot Note: Cerebral amyloid angiopathy (CAA) is a neurological condition in which amyloid protein builds up on the walls of the arteries in the brain. The condition increases an individual’s risk of stroke, brain hemorrhage or dementia. There is no known effective treatment.
The study results, reported by NIH scientists at the National Institute of Allergy and Infectious Diseases (NIAID), are similar to findings from two newly reported human cases of the prion disease Gerstmann-Straussler-Scheinker syndrome (GSS). This finding represents a new mechanism of prion disease brain damage, according to study author Bruce Chesebro, M.D., chief of the Laboratory of Persistent Viral Diseases at NIAID’s Rocky Mountain Laboratories.
Prion diseases, also known as transmissible spongiform encephalopathies, primarily damage the brain. Prion diseases include mad cow disease or bovine spongiform encephalopathy in cattle; scrapie in sheep; sporadic Creutzfeldt-Jakob disease (CJD), variant CJD and GSS in humans; and chronic wasting disease in deer, elk and moose.
The role of a specific cell anchor for prion protein is at the crux of the NIAID study. Normal prion protein uses a specific molecule, glycophosphoinositol (GPI), to fasten to host cells in the brain and other organs. In their study, the NIAID scientists genetically removed the GPI anchor from study mice, preventing the prion protein from fastening to cells and thereby enabling it to diffuse freely in the fluid outside the cells.
The scientists then exposed those mice to infectious scrapie and observed them for up to 500 days to see if they became sick. The researchers documented signs typical of prion disease including weight loss, lack of grooming, gait abnormalities and inactivity. But when they examined the brain tissue, they did not observe the sponge-like holes in and around nerve cells typical of prion disease. Instead, the brains contained large accumulations of prion protein plaques trapped outside blood vessels in a disease process known as cerebral amyloid angiopathy, which damages arteries, veins and capillaries in the brain. In addition, the normal pathway by which fluid drains from the brain appeared to be blocked.
Their study, Dr. Chesebro says, indicates that prion diseases can be divided into two groups:
- those with plaques that destroy brain blood vessels
- those without plaques that lead to the sponge-like damage to nerve cells
Dr. Chesebro says the presence or absence of the prion protein anchor appears to determine which form of disease develops.
The new mouse model used in the study and the two new human GSS cases, which also lack the usual prion protein cell anchor, are the first to show that in prion diseases, the plaque-associated damage to blood vessels can occur without the sponge-like damage to the brain. If scientists can find an inhibitor for the new form of prion disease, they might be able to use the same inhibitor to treat similar types of damage in Alzheimer’s disease, Dr. Chesebro says.
Source: NIH News
Personalized Medicine Approach Provides More Benefit for Patients with High Cholesterol than Current Guidelines
February 24, 2010 | by
Statins are a class of drugs that lower cholesterol and thereby reduce the risk of heart disease and stroke. They work by preventing the synthesis of low-density lipoprotein (LDL or “bad cholesterol”) in the liver and promoting its clearance from the blood. They are the most effective cholesterol-lowering drugs currently available and are the cornerstone of the National Heart, Lung, and Blood Institute’s National Cholesterol Education Program (NCEP) treatment guidelines.
The NCEP recommends a “treat-to-target” strategy, in which patients are given specific statin doses to achieve a desired level of LDL cholesterol in the blood. In this case, low LDL cholesterol is the “target.” Yet some physicians are questioning whether treating to any target is the best approach to fighting disease. A recent study in the Annals of Internal Medicine suggests that “tailored treatment”, an approach attempts to practice personalized medicine by estimating three factors, is more effective than a treat-to-target strategy [1].
WHI Study Data Confirm Short-Term Heart Disease Risks of Combination Hormone Therapy for Postmenopausal Women
February 16, 2010 | by
New analyses from the Women’s Health Initiative (WHI) confirm that combination hormone therapy increases the risk of heart disease in healthy postmenopausal women. Researchers report a trend toward an increased risk of heart disease during the first two years of hormone therapy among women who began therapy within 10 years of menopause, and a more marked elevation of risk among women who began hormone therapy more than 10 years after menopause. Analyses indicate that overall a woman’s risk of heart disease more than doubles within the first two years of taking combination HT.
The difference in the initial level of risk does not appear related to age, based on findings that the increased risk of heart disease was similar between women in their 50s on combination hormone therapy and women in their 60s.
The study is in the Feb. 16, 2010, Annals of Internal Medicine. The WHI is sponsored by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health (NIH).
Even With Heart Disease Awareness on the Rise, Prevention Remains Critically Important for American Women
February 2, 2010 | by
In recognition of American Heart Month, the National Heart, Lung, and Blood Institute (NHLBI) and its heart disease awareness campaign — The Heart Truth — is reminding all American women that heart disease prevention remains critically important, despite that fact that awareness is at an all time high. More women than ever know that heart disease is their leading killer, yet millions of women are at risk, at increasingly younger ages.
Even with increased awareness, 80 percent of midlife women (ages 40 to 60) still have one or more of the modifiable risk factors “” high blood pressure, high cholesterol, overweight/obesity, physical inactivity, diabetes, and smoking. Sixty percent of younger women, ages 20-39, have one or more of these risk factors. Recent data show high rates of overweight/obesity in younger women, which may lead to higher rates of heart disease in later years.
