The role of hoarseness in the reflux symptom index: diagnostic overlap between laryngopharyngeal reflux and dysphonia

Abstract Background The Reflux Symptom Index (RSI) is widely used for assessing laryngopharyngeal reflux (LPR). However, hoarseness—a symptom included in the RSI—may arise from numerous non-reflux-related voice disorders, which can inflate scores and compromise diagnostic specificity. Methods This retrospective study included 239 patients diagnosed with voice disorders. Voice Handicap Index (VHI) and RSI scores were obtained from clinical records. Gastroesophageal reflux disease (GERD) was confirmed by 24-h oesophageal pH monitoring. Univariate linear regression and multivariate generalised linear modelling were performed to examine the relationship between VHI, GERD, and RSI scores. Results Univariate analysis revealed that each 1-unit increase in VHI score corresponded to a 0.348-unit increase in RSI score (B = 0.348, SE = 0.056, p < 0.001). Multivariate analysis confirmed that VHI remained an independent predictor of RSI, irrespective of GERD status ( p < 0.001). Overall, 59% of patients had RSI scores ≥ 13, including 41.5% of those without GERD, suggesting substantial diagnostic overlap. Conclusion Hoarseness-related voice handicap significantly elevates RSI scores independent of reflux status. Clinicians should exercise caution when interpreting elevated RSI values in patients with voice disorders and consider complementary diagnostic tools to prevent misdiagnosis and unnecessary antireflux therapy.