New Genes Found that Control Blood Pressure
In one of the largest genomics studies ever, an international research consortium that includes NIH has identified 29 genetic variations across 28 regions of the human genome that influence
blood pressure. This unprecedented effort brought together more than 230 researchers across 6 continents and scanned the genomes of more than 200,000 people. Results appeared in the Sept. 11 Nature.
Sixteen of the 29 variations identified in the study were previously unrecognized. Six of the new variations were found in genes already suspected
of regulating blood pressure; the other 10, which were found in unexpected locations, provide new clues into how blood pressure is regulated. Individually, the genetic variations increased the risk of hypertension (high blood pressure) by only a tiny amount. For people with multiple variants, however, the effects were more significant.
The primary group of 200,000 participants was of European background and included subjects selected from several NHLBI study populations including the Framingham Heart Study. The research consortium then followed up its analysis
on 70,000 people of East Asian, South Asian and African ancestry. Researchers found the genetic risk score and several of the individual variants were associated with increased blood pressure in these ethnic groups as well.
Stroke Prevention Trial Has Immediate
Implications for Clinical Practice
Patients at a high risk for a second stroke who received intensive medical treatment had fewer strokes and deaths than patients who received a brain stent in addition to the medical treatment,
a large nationwide clinical trial has shown. Investigators published the results in the online edition of the New England
Journal of Medicine. NINDS funded the trial. The medical regimen included daily blood-thinning medications and aggressive control of blood pressure and cholesterol.
New enrollment in the study was stopped in April because early data showed significantly more strokes and deaths occurred among the stented patients at the 30-day mark compared to the group who received the medical management
In addition to the intensive medical program, half of the patients in the study received an intervention of a self-expanding stent that widens a major artery in the brain and facilitates blood flow. One possible explanation for the higher
stroke rate in the stented group is that patients who have had recent stroke symptoms sometimes have unstable plaque in their arteries that the stent could have dislodged, the study authors suggest.
Two Doses of HPV Vaccine May Be as Protective as Full Course
Two doses of the human papillomavirus (HPV) vaccine Cervarix were as effective as the current standard 3-dose regimen after 4 years of follow-up, according to NCI researchers and their colleagues. Results of the study, based on data from a community-based clinical trial of Cervarix in Costa Rica, appeared online Sept. 9 in the Journal of the National Cancer Institute.
Worldwide, approximately 500,000 new cases of cervical cancer are diagnosed every year and about 250,000 women die from the disease. An overwhelming majority of these new cases and deaths occur in low-resource countries. Virtually
all cases of cervical cancer are caused by persistent infection with HPV. Cervarix
is one of two vaccines approved by the Food and Drug Administration to protect against persistent infection with two carcinogenic HPV types, 16 and 18, which together account for 70 percent of all cervical cancer cases. The vaccine
is intended to be administered in 3 doses given over the course of 6 months. To date, investigators have observed up to 8 years of protection from persistent HPV infection with the vaccine. Studies are ongoing to determine the maximum length of protection.
Violence During Pregnancy Linked to Reduced Birth Weight
Pregnant women who are assaulted by an intimate partner are at increased risk of giving birth to infants of reduced weight, according to a population-level analysis
of domestic violence supported by NICHD. Study findings were published online in the Journal of Human Resources.
The study analyzed medical records of more than 5 million pregnant women in California over a 10-year period. Although the results showed a pattern of low-weight births among women who experienced an assault, the study was not designed to establish cause and effect and so could not prove that violence caused the reduced birth weights. Similarly, the study was not designed to provide
a biological explanation for how violence against an expectant mother might cause her child to be of lower birth weight.
Infants born to women who were hospitalized for injuries received from an assault during their pregnancies weighed, on average, 163 grams, or one-third pound, less than did infants born to women who were not hospitalized, the study found. Assaults in the first trimester were associated with the largest decrease in birth weight.
Infants born weighing less than 2,500 grams, or 5.5 pounds, are considered low birth weight and have an increased risk of death or of developing several health and developmental disorders.—compiled by Carla Garnett