Asthmatic adults living in inner-city areas are often allergic to many triggers, such as dust mites or pets, but this sensitisation does not appear to increase the severity of their asthma. "We were expecting that sensitisation would be related to worse asthma outcomes, as in children," lead investigator Dr Juan P. Wisnivesky told Reuters Health.
"Inner-city adults are heavily exposed to these allergens and are commonly sensitised - as shown in our study, as well as by others," he noted. "Thus, we were expecting to find an association between sensitisation and asthma control."
Wisnivesky, from the Mount Sinai School of Medicine, New York, and his associates evaluated 245 inner-city adults with persistent asthma. The patients were mostly women, insured by Medicaid. Sixty percent were Hispanic, 30% African American, and 5% were white. The average income for most patients was less than $15,000 per year.
After being tested for sensitisation to cockroaches, dust mites, cat, mold and mouse, 152 (62 percent) of the patients were found to be positive for at least one of these indoor allergens.
However, scores on a standardised questionnaire assessing asthma control were not significantly worse among patients sensitised to indoor allergens compared with those who were not, the team reports in the Journal of Allergy and Clinical Immunology.
"This is not to say that there is not an important allergic component to asthma," Wisnivesky commented. "The point is that these factors may be more relevant in children than in adults."
Given these results, Wisnivesky says doctors with adult asthma patients should "focus less on assessing sensitisation or educating the patients on environmental factors, and pay attention to other issues, such as how patients use their inhaled corticosteroids or if they understand that asthma is a chronic disease."