Life-long endogenous estrogen exposure is associated with prevalence of allergic rhinitis in postmenopausal women

OBJECTIVES: The aim of the study was to investigate the influence of life-long endogenous estrogen exposure on prevalence of chronic rhinitis including allergic rhinitis (AR) in the postmenopausal period. METHODS: In this cross-sectional study, a total of 3,043 postmenopausal women who participated in the Korea National Health and Nutrition Examination Survey V were included. Participants with symptoms including sneezing, rhinorrhea, nasal obstruction, or nasal itching were considered to have chronic rhinitis. In subgroup analysis, the AR group comprised participants with rhinitis with positive findings in at least one of three specific immunoglobulin E. Univariable and multivariable logistic analyses were performed to evaluate the relationship between rhinitis and estrogen-related factors including age at menarche, age at menopause, age at first delivery, parity, and duration of breast-feeding. RESULTS: Participants with chronic rhinitis (17.6%) had higher parity (odd ratio [OR] = 1.17, P = 0.0135) and shorter duration of breast-feeding (OR = 0.98, P = 0.0388) than controls. In subgroup analysis, participants with AR (7.1%) had younger age at menarche (OR = 0.56, P = 0.0028) and older age at menopause (OR = 1.42, P = 0.0060) after adjustment of confounding factors. There was a positive association between age at menopause and specific immunoglobulin E for both cockroach (OR = 1.38, P = 0.0132) and dogs (OR = 1.38, P = 0.0302). Longer postmenopausal duration was positively associated with cockroach allergen sensitization (OR = 1.25, P = 0.201). CONCLUSIONS: Longer duration of reproductive period was associated with higher prevalence of AR and aeroallergen sensitization in the postmenopausal period. Moreover, cockroach allergen sensitization was associated with a longer postmenopausal period.