The elderly are at risk for chronic rhinitis as the mucous membranes become dry with age. Women are at higher risk for rhinitis during pregnancy. Risk Factors for Allergic Rhinitis Family History. About 26 million Americans have seasonal allergic rhinitis and up to 40 million may have mild symptoms. It is the most common chronic condition in childhood.
Genetic factors are the major determinants of allergies.
Children with family members who are allergic are at highest risk, but allergies can develop in anyone. One theory to explain this observation is that infants born in the fall spend more time in the house during their first year of development and are, therefore, exposed to higher levels of house dust, an important allergen. Another study found that those born in winter months had an increased risk for allergies to house dust. The current climatic phenomenon, El Nino, which causes mild winters and heavy rains, may currently be making allergies worse by causing plants to pollinate earlier and increasing the incidence of molds. Although allergies often appear first in childhood, they may develop at any age.