After studying 138 pregnant women with asthma through their entire term, researchers have concluded that a female fetus exerts an adverse effect on maternal asthma, which, if the mother is not treated with inhaled glucocorticoids, results in reduced fetal growth. Investigators examined the effects of asthma on the endocrine and immune relationships between mother, placenta, and fetus. The investigators were looking specifically at the role of each component on the control of human growth during pregnancy. They studied the 138 pregnant women with asthma plus 44 pregnant women without asthma who served as controls. They found that inhaled glucocorticoid intake by women with asthma who used moderate or high doses of the drug significantly increased in later pregnancy when women were pregnant with a female fetus, suggesting an up-regulation of inflammation associated with asthma as gestation progressed. The researchers said that their study results indicate that in pregnant women with asthma there is reduced female fetal growth when no inhaled glucocorticoids are used. Female birth weight and head circumference were both reduced to the 34 percentile, while the weight index was normal, suggesting symmetrical growth restriction. They said that the use of glucocorticoids to control asthma inflammation by women with mild asthma was associated with female birth weight percentages that were comparable to control subjects with no asthma. In addition, they noted that male fetuses seem to be insensitive to the effects of inflammation in the mother. The study appears in the first issue for December 2003 of the American Thoracic Society's peer-reviewed American Journal of Respiratory and Critical Care Medicine.
IMPAIRED AROUSALS ASSOCIATED WITH SUDDEN INFANT DEATH SYNDROME
Using data from sleep studies on over 20,000 babies that were conducted at 10 hospitals in Belgium, researchers found that infants who died 3 weeks later of sudden infant death syndrome (SIDS) were characterized during their sleep test by incomplete arousal processes. Investigators from Belgium compared the arousal processes of 16 infants monitored some weeks before they died of SIDS and compared them with 16 normal control infants. Both study groups consisted of 6 girls and 10 boys. Their median age during the sleep recordings was 11 weeks. The median time between sleep recording and death from SIDS was 21 days. The investigators said that in healthy infants sequential arousals such as sighs, startles, and thrashing limb movements precede full arousal. They noted that complete arousals include both autonomic and cortical activation. Alternatively, subcortical or autonomic activation with no cortical involvement represents an incomplete arousal reaction. They pointed out that the future SIDS victims had fewer cortical arousals between 3 a.m. and 6 a.m. when most SIDS events occur. They said that cortical arousal permits the initiation of behavioral responses that protect from life-threatening stimuli such as moving away from bedding which has obstructed the airways when sleeping facedown. The study appears in the first issue for December 2003 of the American Thoracic Society's peer-reviewed American Journal of Respiratory and Critical Care Medicine.
ACTIVE CIGARETTE SMOKING INTERFERES WITH HIGH-DOSE ORAL CORTICOSTEROID TREATMENT IN ASTHMATIC PATIENTS
The first randomized, placebo-controlled study to demonstrate that active cigarette smoking is associated with resistance to short-term, high-dose oral corticosteroid treatment in patients with chronic stable asthma is published in the first issue for December 2003 of the American Thoracic Society's peer-reviewed American Journal of Respiratory and Critical Care Medicine. Scottish investigators studied 50 patients, including 14 smokers, 10 ex-smokers, and 26 never-smokers. According to the authors, for all end point results, including those from such tests as forced expiratory flow in one second and morning/nighttime peak expiratory flows, the control of asthma score, plus daytime and nighttime symptoms, there was significant improvement after treatment with oral corticosteorids in the never-smokers, but no change in the values for current smokers. The investigators concluded that active smoking impairs the efficacy of short-term oral corticosteroid treatment for chronic asthma patients. They pointed out that active cigarette smoking is common in adult patients with asthma, with over 20 percent being current smokers. They noted that a recent survey of adults in emergency departments who had acute asthma revealed that 35 percent were cigarette smokers. They point out that their findings suggest that alternative anti-inflammatory treatment might be required for smokers with asthma. In addition, they emphasize that their study results serve to emphasize the importance of smoking cessation for asthma patients.
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Journal
American Journal of Respiratory and Critical Care Medicine