The Prevalence of Hypopharynx Findings Associated with Gastroesophageal Reflux in Normal Volunteers

Abstract

Routine laryngeal examination of patients with otolaryngologic complaints often reveals findings thought to result from gastroesophageal reflux. The direct association between these mucosal findings and uncontrolled reflux is not well established. To begin exploring the specificity of tissue signs, 105 normal, healthy, adult volunteers were examined by routine video fiber-optic endoscopy for the presence of findings attributed to reflux disease. Medical conditions, lifestyle factors, and ENT complaints were surveyed to reveal potential airway irritants, while the study design attempted to eliminate silent reflux. The majority of subjects (86%) had findings associated with reflux and certain signs reached a prevalence of 70%. Prevalence was not affected by ENT complaint, smoking, alcohol, or asthma. Intraexaminer and interexaminer agreement information is provided. The traditional attribution of hypopharynx irritation signs to reflux is challenged; the need for improved diagnostic specificity is highlighted.

Introduction

The pervasiveness of acid reflux in the general population is well established, with occurrence on a daily or monthly basis estimated to be 7% and 25%, respectively.¹ There is growing evidence that gastroesophageal reflux disease (GERD) creates ear, nose, and throat (ENT) symptoms secondary to tissue irritation.2, 3, 4, 5, 6, 7, 8 At least 4% to 10% of patients seeking help from ENT physicians are perceived as suffering from reflux-based complaints.³ Establishing the specific relationship among symptoms, signs, and etiology in this clinical population is necessary for optimal diagnosis and treatment, but consensus on these relationships is lacking.⁹

Suspected GERD-related ENT complaints are routinely treated medically by otolaryngologists or are referred to gastroenterologists for evaluation. These current clinical practices are based on several relevant issues including: (1) observation of tissue irritation, (2) the propensity of this irritation to be geographically near the upper esophageal sphincter, (3) concomitant patient complaints suggestive of reflux, and (4) the clinical experience of symptom improvement gained on a therapeutic trial of antireflux medication. While this empirically based evidence accounts for current practice patterns, there are several challenging questions left unanswered. These include: (1) Are the tissue irritation findings for reflux specific in presentation from that of other airway irritants? (2) Does tissue irritation in the larynx/pharynx represent a continuum for both type and severity, and if so, are signs of irritation ever present in the normal nonpatient population? (3) Are the tools of endoscopy adequate for both specificity and sensitivity of clinical diagnosis? and (4) Are the observed clinical benefits from antireflux medical trials causal or coincidental? Most clinicians would readily acknowledge the comfort and ease of diagnosing severe cases of reflux when tissue signs are dramatic. Unfortunately, most of the patient population presents with subtle profiles, thereby complicating interpretation. This clinical dilemma will continue until a specific and reliable definition of reflux signs can be established.

A logical first step would involve the study of the “normal,” nonclinical population for evidence of findings classically attributed to reflux. Such exploration might help define one end of a possible mucosal tissue health continuum. One recent investigation uncovered a high incidence of posterior erythema (73%), suggestive of reflux in a group of asymptomatic singing students.¹⁰ A second study of normal singers documented, via endoscopic examination, more than a 70% prevalence of tissue changes suggestive of reflux in a group of 24 experienced singing teachers without vocal complaints.¹¹ In a third study, computer color analysis of laryngoscopic images from seven normal subjects revealed redness (“erythema”) ratings of the posterior larynx that, while less than in patients with laryngitis, were still present.¹² As part of a fourth study that investigated the validity and reliability of the reflux finding score (RFS) in reflux patients, the authors examined 40 normal controls without symptoms of voice problems, gastroesophageal reflux disease, or laryngopharyngeal reflux. The results document that exam findings consistent with reflux are present in these normal controls.¹³ A fifth “normals” study attempted to define the presence of physiologic laryngopharyngeal reflux in healthy subjects with no history of symptoms, suggestive of reflux and without signs of hypopharynx irritation. More than half of the 30 subjects had at least one episode of proximal reflux and 80% of those reflux events occurred in the upright position.¹⁴ In combination, these “normals” studies document the occurrence of both measured reflux and tissue irritation signs, suggestive of reflux in asymptomatic, healthy individuals. However, further research is needed to determine whether the physical findings are actually representative of reflux versus other airway irritants or represent variations of normal anatomy.

This study represents the first, large, systematic effort to explore the prevalence of tissue irritation signs typically associated with GERD in a normal healthy, volunteer population. A related aim of the work is to assess the contribution of tissue irritating factors other than acid reflux to the observed signs of irritation. This investigation represents one component of a series of studies designed to operationally define the clinical manifestations of reflux disease, as well as to explore the specificity and sensitivity of endoscopic findings.