Allergy gap between Finnish and Russian Karelia on increase

Area of Science:

• Epidemiology
• Immunology
• Environmental Health

Background:

• Global trends show shrinking East-West gradients in atopic disease prevalence.
• Previous studies indicate regional disparities in atopy and atopic disease occurrence.

Purpose of the Study:

• To assess changes in atopy and atopic disease prevalence in Finnish and Russian Karelia over 10 years.
• To investigate the impact of birth year on atopy prevalence in these regions.

Main Methods:

• Two cross-sectional surveys conducted in 1997/1998 and 2007 using identical methodologies.
• Inclusion of randomly selected adults aged 25-54 from Finnish and Russian Karelia.
• Collection of serum for IgE measurements and clinical data via questionnaires.

Main Results:

• Finnish sensitization rates to birch pollen and cat allergens significantly increased, while total IgE remained stable.
• Russian sensitization rates showed no significant increase, but total IgE decreased significantly.
• Atopy prevalence increased with birth year in Finland but remained stable in Russia.
• Physician-diagnosed asthma and hay fever prevalence increased in Finland.

Conclusions:

• Atopy and atopic disease prevalence disparities between Finnish and Russian Karelia have widened.
• The 'allergy epidemic' persists in Finland, driven by birth year effects on atopy.
• No 'allergy epidemic' signs in Russia; decreasing total IgE may suggest environmental exposure changes.