However, the study also found that rates of systemic allergic reactions -- including the severe condition known as anaphylaxis -- have surged in the past 20 years.
The researchers analyzed data gathered from numerous sources: national surveys, primary care doctors, prescription and hospital admission records, and death records.
Over the past three decades, diagnoses of allergic rhinitis and eczema in children have tripled, but there appears to have been a recent decrease in the prevalence of symptoms. Hospital admissions for eczema have stabilized since 1995, the researchers found, while admissions for allergic rhinitis have decreased to about 40 percent of their 1990 levels.
Between 1971 and 1991, the number of consultations with family doctors about hay fever increased by 260 percent and by 150 percent for eczema. However, these rates have stabilized in the past 10 years, the study said.
Hospital admissions for anaphylaxis have soared by 700 percent, for food allergy by 500 percent, and for the skin allergy urticaria by 100 percent.
Prescriptions for all types of allergies have increased since 1991.
The researchers said that some of the trends could be related to changes in medical practice and care but could also be explained by changes in the sources of allergic disease.
The study was published in the current issue of Thorax.
HealthDay News, September 7, 2006