Increasing Incidence of Food Allergies in Olmsted County, MN

Rationale:

There is a growing epidemic of food allergies in the western hemisphere, with current prevalence estimates of 6-8%.  One prior study determined the incidence of peanut allergy to be 68.8/100,000 person-years in 2007.  The incidence of all food allergies remains unknown.

Methods:

We undertook a historical cohort study to describe the epidemiology of food allergy in Olmsted County, Minnesota using the Rochester Epidemiology Project.   

Results:

There were a total of 513 subjects (222 males, 291 females) with physician diagnosed food allergy over the 2006-2011year period. The overall incidence of food allergy was 61/100,000 person –years.

The incidence peaked at 75/100,000 person-years over the study period in 2009 and plateaued to 57/100,000 person-years in 2011.

For the pediatric age group (children </=18 yrs age), the overall incidence was 195/100,000 person-years, with a higher incidence of 237/100,000 person-years in females and 154/100,000 person-years in males.  There was no significant change in antibiotic usage over time; 43% of the cohort was exposed to antibiotics prior to food allergy diagnosis in 2006, versus 69% of the cohort in 2011 (p=0.3)

40% of the children also had reactive airway disease/asthma and 54% children had co-existent atopic dermatitis.

There was low association with antibiotic allergy in this cohort with only 25/513 ( 5%) children with penicillin allergy and 20/513 (4%) reporting other medication allergy. 

Conclusions:

This is one of the first population-based studies examining the incidence of all types of food allergies.  The food allergy incidence in Olmsted County peaked in 2009 at 75/100,000 person years.