News in brief - June 23, 2003

Hypertension and eye disease linked - Breast cancer survivors may have lower heart attack risk - Bacteria-eating virus, not germs, spread disease in day-care setting

Hypertension and eye disease linked

People of African ancestry who have high blood pressure and high blood glucose levels are at increased risk of diabetic retinopathy, according to a new study. A second study of the same population placed those with diabetes and high blood pressure at increased risk for elevated intraocular pressure.

The dangers were noted in two studies published in the May Ophthalmology, the clinical journal of the American Academy of Ophthalmology.

In the first study, 410 people ages 40 to 84 who had diabetes were assessed four years after an initial examination. Researchers found that 30% who did not have diabetic retinopathy at their first assessment developed the condition at follow-up. Their risk for retinopathy increased with higher systolic blood pressure and indications of poor diabetes control, such as elevated glycated hemoglobin levels, said the researchers.

The second study of about 3,000 people found that diabetes and hypertension were related to an average 2.5 mmHg increase in intraocular pressure.

Breast cancer survivors may have lower heart attack risk

Women who survive breast cancer may be less likely to have a cardiac event, according to a study published online this month in Cancer, the journal of the American Cancer Society. The article will be in the July 1 print edition.

Researchers at the University of Chicago and Harvard Medical School analyzed data on more than 5,000 women from the National Cancer Institute's Surveillance, Epidemiology, and End Results program and 20,000 women without cancer enrolled in Medicare from 1993 to 1998. They found that women with a history of breast cancer had a 34% reduced risk of a heart attack. Those with breast cancer and a known risk factor for heart disease reduced risk by 50%.

Authors theorized estrogen -- a known cardioprotective agent but also a known carcinogen -- may be the key player in this phenomenon and suggested that selective estrogen receptor modulators may play a key role in reducing the cardiac risk of women without breast cancer.

Bacteria-eating virus, not germs, spread disease in day-care setting

A strep-infected child in a day-care center plays with a toy, puts it in her mouth and crawls away. Another child plays with the same toy and comes down with strep.

Until now, scientists thought that disease-causing bacteria left on the toy was the culprit in transferring the disease from the first child to the second. New research published in the June Infection and Immunity claims that the culprit sometimes might not be the bacteria but a virus that infects and destroys the bacteria. Called a bacteriophage, or phage, this "bacteria-eating" virus causes diseases by transferring toxins and other disease-causing genes between bacteria.

The findings show for the first time that bacteriophage, previously thought not to be infectious to humans, may be a new target for fighting certain bacteria that produce toxins.

"Controlling the phage may be as important as controlling the bacteria," said senior author Vincent A. Fischetti, PhD, professor and head of the Laboratory of Bacterial Pathogenesis and Immunology at Rockefeller University in New York.

"It's possible that phage present in the saliva of a child or another individual can cause the conversion of an existing non-toxigenic organism to a toxigenic one," said Dr. Fischetti.