Is laryngopharyngeal reflux related to functional dysphonia?

Laryngopharyngeal reflux (LPR) may be a contributing factor in chronic hoarseness. The association of LPR with functional dysphonia (FD), the most common voice clinic diagnosis, is unknown. We attempted to determine whether patients with FD have a higher rate of laryngeal exposure to acidic stomach contents than do healthy volunteers.

We recruited through the voice clinic 23 patients who had had persistent dysphonia for 3 months. Pregnancy, major structural laryngeal abnormality, and vocal fold paralysis were exclusion criteria. Eight healthy volunteers were recruited. The subjects gave informed consent to enter the study, which had the approval of our hospital ethics committee. The patients and control subjects underwent 24-hour dual-probe pH-metry.

Twenty-two patients and 6 control subjects completed the study. Overall, there seemed to be no statistical differences between patients and controls on all but 2 channel 1 pH-metry parameters. These were the longest reflux episode (seconds) in a supine position, and the fraction of time the pH was less than 4 in a supine position. Both of these time periods were longer in patients than in the controls (p < .05).

Our study demonstrated an association between LPR and FD for 2 pH parameters. Larger studies are required to assess the potential relationship between nonorganic dysphonias and reflux. Furthermore, the presence of a multifactorial causation of FD, including "medical" and psychological causes, should be addressed in future studies.