American Thoracic Society news tips for February

EXPOSURE TO TOBACCO SMOKE IN THE WOMB INCREASES CHILDRENS’ ASTHMA RATE

Researchers who studied 5,762 school-aged children residing in 12 southern California communities found that exposure to environmental tobacco (ETS) in the womb increased the rate of physician-diagnosed asthma. Investigators studied responses to a self-administered questionnaire completed by parents of 4th, 7th , and 10th grade students to ascertain which children had either wheezing or physician-diagnosed asthma. ETS exposure in the womb occurred in 18.8 percent of the children, with 39.5 percent incurring some lifetime exposure to tobacco smoke. According to the study, the lifetime prevalence of wheezing among the children was 33.7 percent. Physician-diagnosed asthma was reported by 14.6 percent. The research appears in the February issue of the American Journal of Respiratory and Critical Care Medicine.

ENDOTOXIN EXPOSURE CAUSES WHEEZING IN FIRST YEAR OF LIFE

Endotoxins, tiny molecules that form the outer membrane of gram negative bacteria which are found in house dust, were associated with infant wheezing and could promote persistent wheezing during the first year of life among babies with a family history of allergy or asthma. The researchers found that exposure to elevated levels of endotoxin, often in family room and bed dust, caused airway inflammation, triggering wheeze and promoting persistent wheeze in some infants. During the first three months after birth, the investigators visited 499 infants’ houses and vacuumed dust from multiple sites throughout the dwelling. They found that endotoxin in family room dust was strongly and significantly associated with endotoxin in baby’s bed dust. They also found that the presence of a dog in the house had a strong and significant association with measured endotoxin in family room dust. The researchers noted that, in white infants, the elevated endotoxin exposure was associated with a 56 percent increased risk of repeated wheeze. The study appears in the February American Journal of Respiratory and Critical Care Medicine.

HORMONE REPLACEMENT THERAPY LEADS TO BETTER PULMONARY FUNCTION AND LESS PULMONARY OBSTRUCTION

A group of postmenopausal women who used hormone replacement therapy (HRT) had better pulmonary function and less pulmonary obstruction, according to published results from the Cardiovascular Health Study. Out of 3,393 female participants, the researchers had information on HRT use and pulmonary function for 2,353. All women involved in the study were interviewed and received medical examinations. Of the group, 61.5 percent reported never using HRT, 22.6 percent had prior use, and 16 percent were current users. They found that the mean values of lung function tests were significantly higher among current HRT users by anywhere from 8 to 10 percent. Also, current HRT users were about 25 percent less likely to have pulmonary obstruction than women who did not currently use HRT. The research appears in the February issue of the American Journal of Respiratory and Critical Care Medicine.

For either the complete text of these articles or to contact the investigators by e-mail, please see the ATS Journal Online Website at http://www.atsjournals.org. Medical and scientific journalists who would like to interview these researchers, receive a complimentary subscription to ATS journals, and/or receive the ATS news briefs by e-mail each month, should contact Lori Quigley at 212-315-6442, by fax at 212-315-6455, or by e-mail at lquigley@thoracic.org.