Prolonged breastfeeding and protective effects against the development of allergic rhinitis: A systematic review and meta-analysis

Abstract

Background: There is insufficient evidence to confirm the protective effects of prolonged breastfeeding against the development of allergic rhinitis (AR). Methodology: A systematic review and meta-analysis was performed to assess the associations between prolonged breastfee¬ding and AR symptoms later in life. Comparisons were conducted between breastfeeding durations <6 months and ≥6 months and between <12 months and ≥12 months. Exclusive breastfeeding and nonexclusive breastfeeding were analysed separately. Outcomes were risks of AR development later in life. Results: Twenty-three observational studies (161,611 children, age 2-18 years, 51.50% male) were included. Two studies (9%) were with high quality. Both exclusive and nonexclusive prolonged breastfeeding (≥6 months) decreased the risk of AR. The long-term (≥12 months) nonexclusive breastfeeding lowered the likelihood of AR compared to the <12 months. The long-term exclusive breastfeeding did not show the same protective effect; however, this result was restricted to only one study. Conclusions: Exclusive breastfeeding and nonexclusive breastfeeding for ≥6 months may have protective effects against the development of AR up to 18 years of age. The findings should be interpreted with caution given the limitation of low-quality observational studies.