Risk factors associated with functional esophageal disorders (FED) versus gastroesophageal reflux disease (GERD)

Despite the high prevalence of typical symptoms of gastroesophageal reflux disease (GERD), approximately 30% of patients have functional esophageal disorders (FED) on ambulatory reflux monitoring, which may include reflux hypersensitivity (RH; defined as physiologic acid exposure but temporally correlated symptoms of reflux), or functional heartburn (FH; defined as physiologic acid exposure and negative symptom correlation). There are limited epidemiological data characterizing these conditions. We investigated demographic and socioeconomic factors as well as medical comorbidities which may predispose to FED versus pathologic GERD.

Adult patients with reflux symptoms for at least 3 months were studied with 24-h pH-impedance testing from 11/2019 to 3/2021. Participants were categorized into pathologic GERD, FH, or RH using pH-impedance data and reported symptom correlation. Demographic data, including age, gender, race/ethnicity, zip code, insurance status, and medical comorbidity data were retrospectively retrieved from the electronic medical record on all participants.

229 patients were included. Non-Hispanic Asian ethnicity (OR 5.65; p = 0.01), underweight BMI (OR 7.33; p = 0.06), chronic pain (OR 2.33; p < 0.01), insomnia (OR 2.83; p = 0.06), and allergic rhinitis (OR 3.90; p < 0.01) were associated with a greater risk for FED. Overweight BMI (OR 0.48; p = 0.03) and alcohol use (OR 0.57; p = 0.06) were associated with a decreased risk for FED.

This is the first report of a greater risk of FED in patients with underweight BMI, insomnia, chronic pain, allergic rhinitis, or of Asian or Hispanic ethnicities. The weak associations between female gender and anxiety are corroborated in other studies. Our findings enable clinicians to better screen patients with reflux for this disorder.