News in brief - Sept. 12, 2005

FDA OKs blood test that could be a step closer to personalized medicine - Frequent use of painkillers increases hypertension risk - Defect in part of brain that daydreams linked to Alzheimer's - Soy could reduce triglyceride levels, hot flashes

FDA OKs blood test that could be a step closer to personalized medicine

The Food and Drug Administration approved a new blood test Aug. 22 that will join several others intended to help physicians make personalized drug treatment decisions for patients.

The Invader assay detects variations in the UGT1A1 gene that produces an enzyme active in the metabolism of drugs such as irinotecan, used in colorectal cancer treatment.

The assay will help determine whether a drug dose suitable for one patient may be too high for another.

There is a growing list of such genetic tests on the market. One test individualizes doses of antidepressants, antipsychotics and some chemotherapy drugs, and another detects variations in the genome of HIV that makes the virus resistant to some anti-retroviral drugs.

Frequent use of painkillers increases hypertension risk

Women who take acetaminophen or ibuprofen are more likely to develop hypertension, according to a study in the Aug. 25 Hypertension: Journal of the American Heart Assn.

Researchers analyzed data from the Nurses Health Studies I and II. Older women from the first study who took more than 500 mg per day of acetaminophen were 93% more likely to develop hypertension. Younger women from the second study who used the drug at this dosage were 99% more likely. Older women who used more than 400 mg of ibuprofen daily were 78% more at risk for hypertension, and younger ones were 60% more at risk. No increased risk was found with aspirin use.

Defect in part of brain that daydreams linked to Alzheimer's

The areas of the brain activated when young adults daydream are the same ones that fail in Alzheimer's patients, according to a paper in the Aug. 24 Journal of Neuroscience.

Researchers, using five different imaging techniques, found that Alzheimer's patients had the most problems in the posterior cingulate, retrosplenial and lateral parietal cortex. Authors of the paper suggest that these data may lead to a new theory of what causes this disease.

"It may be the normal cognitive function of the brain that leads to Alzheimer's later in life," said Randy L. Buckner, PhD, lead author and a Howard Hughes Medical Institute investigator at Washington University in St. Louis. "This was not a relationship we had even considered."

Soy could reduce triglyceride levels, hot flashes

Daily consumption of soy protein found in tofu and other soybean products may result in a small reduction in low-density lipoprotein and triglyceride levels, according to a review of 68 studies by the Agency for Healthcare Research and Quality.

In addition, isoflavones found in soy may reduce the frequency of hot flashes in postmenopausal women, said agency reviewers.

But the studies examined were few in number, of poor quality and their duration was too short to lead to definite conclusions, according to an agency report.

Overall, consumption of soy products resulted in a 5 mg/dL, or about 3%, reduction in LDL and an 8 mg/dL, about 6%, decrease in triglyceride levels in the populations studied. Some evidence showed that soy consumption may be more effective at lowering LDL among people with higher levels.

There was a net reduction in hot-flash frequency ranging from 7% to 40%, agency reviewers found.