Bidirectional risk association between adenoid hypertrophy and laryngopharyngeal reflux: A systematic meta-analysis

Adenoid hypertrophy (AH) and laryngopharyngeal reflux (LPR) are common, pathologically linked pediatric otolaryngological conditions; however, their causal relationship and mechanistic underpinnings are presently unclear. This study aimed to explore the association between AH and LPR in pediatric populations.

Two investigators independently performed literature screening across PubMed, Web of Science, and Cochrane Library databases. Newcastle-Ottawa Scale was employed to assess the methodological quality of cohort studies, as well as Appraisal tool for Cross-Sectional Studies was applied for evaluating cross-sectional investigations. The funnel plot was used to analyze publication bias. A meta-analysis of the extracted data was conducted by using R software platform (version 4.4.2, R Foundation, Vienna, Austria).

A total of 18 studies (3 cross-sectional study and 15 cohort studies) were included, including 39,427 participants. Meta-analysis revealed elevated prevalence of LPR among children with AH, with a significantly increased risk of LPR in AH children (odds ratio = 10.53). Meanwhile, children underwent >1 time adenoidectomy (AT) exhibited increased risk of LPR (risk ratio = 9.43). All these data indicated LPR may play a role on AH. However, data from AT studies showed short-term symptoms of LPR could be alleviated (<1 year) after AT, but increased susceptibility to LPR (risk ratio = 2.03) was found with long-term follow-up (>10 years). These results suggested LPR was not only increase the risk of AH but also affected by AH.

This study preliminarily validates the close association between AH and LPR. Future studies employing standardized diagnostic criteria are required to further elucidate the reciprocal relationship between AH and LPR, as the marked heterogeneity among earlier studies has primarily stemmed from variations in diagnostic methodologies.