Asthma Watch

NOVEMBER 01, 2008

Acetaminophen, Childhood Asthma Linked

Children given acetaminophen to reduce fever during their first year of life are more prone to developing asthma as they get older, according to study findings reported in the September 20, 2008, issue of The Lancet. For the study, the researchers collected data on 205,487 children from 31 countries around the world. The children participated in the International Study of Asthma and Allergies in Childhood.

The researchers learned that children had a 46% increased risk of developing asthma when they were 6 to 7 years old. Furthermore, children given high doses of acetaminophen within the past year had a >3 times increased risk of developing the condition. The children given medium doses faced a 61% increased risk of developing asthma. Acetaminophen use also was linked with a greater risk of severe asthma of approximately 22% to 38%, found the researchers.

The researchers concluded that acetaminophen use in large amounts is unnecessary. "It should be limited to high fevers," said lead researcher Richard Beasley, MBChB, FRACP.

Day Care May Lead to Lower Asthma Risk

Children who attend day care may have a lower risk of developing asthma later on, according to a study reported recently in the Journal of Allergy and Clinical Immunology.

For the study, the researchers followed 1085 children from birth to age 5. The results indicated that children who went to day care had a lower risk of wheezing by the time they were 5 years old, compared with children who stayed at home or with a babysitter.

The risk was especially low among children who entered day care when they were between the ages of 6 and 12 months. This group was 75% less likely to develop a wheezing problem, compared with children cared for at home.

Children who attended day care after 12 months had a 35% lower risk of wheezing.

Steroids Less Effective in Obese Patients

Glucocorticoids (steroids) are 40% less effective in overweight and obese asthma patients, compared with normal-weight individuals. The researchers looked at 45 nonsmoking adults and measured the responses of cells to the steroid dexamethasone. Steroids interfere with inflammatory signaling pathways by raising the level of MAP kinase phosphatase-1 (MKP-1).

When the researchers applied dexamethasone to the cultures of the participants? blood cells, they found that steroids did not increase MKP-1 as effectively in overweight and obese patients with asthma, compared with thinner patients with the condition. The steroid increased the levels of MKP-1 by 5.27 times in cultured blood cells from slimmer patients with asthma, compared with an increase of only 3.11 times in overweight and obese patients with asthma. The findings were reported in the October 1, 2008, issue of the American Journal of Respiratory and Critical Care Medicine.

Mortality Higher for Poor Asthma Control, Severity

A study of 865 adults admitted to Kaiser Permanente hospitals for asthma found that greater asthma severity and poorer perceived asthma control are linked with an increased risk of death in adult patients in this patient population.

The study's purpose was to examine the mortality risk factors among these patients. Sociodemographic data, asthma history and severity, health status, and scores on measures of perceived asthma control were recorded and the impact of each factor on mortality was assessed. During the 781 days patients were followed, 123 patients died.

When the researchers factored in other potential influences, the researcher found an association between higher initial severity of asthma scores combined with lower perceived asthma control scores and a greater risk of all-cause mortality.

The findings were reported in the August 2008 issue of the Annals of Allergy, Asthma, and Immunology.

Inhaled Steroid Benefits Go Beyond Asthma Control

Older women with asthma who use inhaled steroids are considerably less likely to die from any cause, compared with women not using the medication.

The findings are based on responses from a 1998 supplementary asthma questionnaire submitted by 2671 women with persistent asthma participating in the Nurses' Health Study. Of the participants, 54% reported inhaled steroid use in 1998. During the next 5 years, 87 women died (22 from cardiovascular disease, 31 from cancer, and 34 from "other" causes).

The researchers found that use of inhaled steroids at the outset was linked with a 42% reduced risk of dying from any cause and a 65% reduced likelihood of dying from a heart-related cause. The study was reported in Chest (September 2008).

F A S T   F A C T: Approximately 15% to 23% of asthma cases in the United States are due to occupational exposures.