New data indicates that a high number of upper respiratory infections during an infant’s first year increases the risk for asthma and early ragweed sensitization at age 7.
To determine the association between first-year upper respiratory infections (URIs) and subsequent ragweed sensitization and asthma, the researchers assessed data from the Cincinnati Childhood and Allergy and Air Pollution Study prospective cohort. Included in the CCAAPS were high-risk births of one or more confirmed allergic parents.
“A high number of respiratory infections early in life is associated with early sensitization to some aeroallergens,” Leilanie Perez Ramirez, MD, MS, of the Cincinnati Children’s Hospital, in Ohio, who presented the data, told Healio Family Medicine. “A high number of respiratory infections (including upper and lower) is associated with early sensitization to ragweed, sensitization to mold at age 3 and asthma at age 7. When combined, having a high number of respiratory infections and early sensitization to mold confers an increased risk for asthma at age 7 compared to either individual risk factor alone.”
The researchers defined arly sensitization as at least one positive skin prick test from ages 1 to 3 years, and late sensitization as negative skin prick tests during 1 to 3 years, but positive at 7 years. Regarding URIs, high frequency was defined as more than six infections by 1 year.