NOVEMBER 01, 2006

Vitamin Levels Linked with Breathing Risk

Vitamin E levels in pregnant women are inversely linked with asthma in their children, according to a study reported in the American Journal of Respiratory and Critical Care Medicine (September 1, 2006). In an earlier study, the researchers found an inverse association between maternal vitamin E levels during pregnancy and the risk of wheezing in their 2- year-old children.

For the current study, the researchers revisited 1861 children from the earlier study at age 5 and assessed their asthma-related outcomes. Food frequency questionnaires and blood tests were used to examine the mothers' nutrient status. Respiratory questionnaires, imaging, and skin-prick tests were used to analyze the presence of asthma in the children.

The results indicated that low maternal vitamin E levels were tied with having a child with asthma, constant wheeze, wheezing, or asthma during the previous year, or ever having a diagnosis of asthma. The inverse association was also seen, with elevated vitamin E levels being linked with a reduced chance of having a child with asthma or related symptoms. The researchers also discovered a negative association between maternal zinc levels and children with active asthma or those who had ever been diagnosed with the disorder. The study indicated that a child's nutrient status was not associated with breathing outcomes.

Asthma Associated with Sleep Disorder

Researchers have found that asthma seems to almost double the risk of obstructive sleep apnea problems in young mothers. The study included 677 women with an average age of about 30 years. Overall, >50% of the women reported that they never snored; however, 34% (231 patients) reported snoring at least 1 night per week, and 13% (85 patients) reported snoring "almost always." Snoring is an indicator of sleep apnea.

The 122 black women in the cohort were significantly more prone to snore, compared with whites. Patients without asthma were also at increased risk for snoring. Furthermore, women diagnosed with asthma and currently having symptoms were 2 times as likely to snore.

"Knowledge that asthma is associated with increased risk of obstructive sleep apnea has the potential of translating into reduced morbidity due to obstructive sleep apnea, by allowing early diagnosis and treatment," concluded lead investigator Maninder Kalra, MD. (The findings were published in the August 2006 issue of the Annals of Allergy, Asthma & Immunology).

Blacks Present to the ER with More Severe Asthma

A study reported in the American Journal of Respiratory and Critical Care Medicine (September 2006) found that blacks who come to the emergency room (ER) for treatment during an asthma attack have more severe flare-ups, compared with whites with the disease. Yet, the 2 groups respond equally well to routine "rescue" treatment.

The researchers investigated asthma attack severity and the effectiveness of beta-2 agonists in 155 adult blacks and 140 adult whites seen at 8 different ERs in the Cleveland, Ohio, area. The results showed that blacks had reduced airflow to their respiratory passages and more serious flare-ups of asthma, compared with the white participants. On the other hand, the beta-2 agonist "albuterol was equally efficacious in both populations, and there was no difference in posttreatment [airflow rates, regardless] of the initial attack intensity," reported the researchers. The researchers also discovered there were no racial differences in the rate of hospital admissions and discharges.

The researchers were unable to determine why blacks have more severe flare-ups in the ER. They suggested that blacks may wait longer to come to the ER and may use short-acting drug therapy too long to try to control the attack at home.

Drug Use "As Needed" Relieves Asthma

The "as needed" recommendation may work for individuals with asthma who are on a drug combo for regular maintenance therapy. Taking the medications only when they have symptoms seems to improve overall asthma control.

The results are based on a study of 3394 patients with moderate-to-severe asthma who still had symptoms while taking budesonide/formoterol maintenance therapy during a 2-week trial period. During episodes of breathing difficulty, the patients were randomly assigned to use either the rapid-acting beta-2 agonist terbutaline, formoterol, or the formoterol/budesonide combo. The researchers found that in terms of delaying the first severe asthma flare-up, the drug combination worked better, compared with formoterol alone, which in turn was more effective than terbutaline.

Formoterol plus budesonide was also notably better in lowering the frequency of asthma exacerbations. With the drug combination, 19 severe flare-ups per 100 patients annually occurred, compared with 37 and 29 flare-ups with terbutaline and formoterol, respectively. The results "challenge the established use of maintenance therapy plus rapid-acting beta-2 agonists as the only means of controlling asthma," concluded the researchers. (The findings were reported in the Lancet, August 26, 2006.)