Marked improvement in nocturnal gastroesophageal reflux in a large cohort of patients with obstructive sleep apnea treated with continuous positive airway pressure.

BACKGROUND: Nocturnal gastroesophageal reflux (nGER) is common in patients with obstructive sleep apnea (OSA). Small, short-term studies have shown that treatment with nasal continuous positive airway pressure (CPAP) decreases esophageal acid exposure.

OBJECTIVE: To examine the relationship between OSA and nGER, and the effect of CPAP on nGER, in a long-term follow-up study of a large cohort of patients with OSA and nGER.

METHODS: We prospectively studied 331 patients diagnosed as having OSA between October 1, 1993, and November 30, 2000. At baseline, patients graded their frequency of nGER symptoms on a scale of 1 (never) to 5 (always). All patients were prescribed CPAP for their OSA. At follow-up, the frequency of nGER symptoms was obtained by telephone interview.

RESULTS: Of the 331 patients with OSA, nGER was present in 204 (62%) before treatment with CPAP. Follow-up was obtained in 181 patients (89%). Of these 181 patients, 165 (91%) were still using CPAP and 16 (9%) were not, forming the treatment and control groups, respectively. The patients compliant with CPAP had a significant improvement in nGER score, from a mean of 3.38 before CPAP treatment to 1.75 after treatment (48% improvement; P<.001), while patients not using CPAP (control subjects) showed no improvement (mean, 3.56 to 3.44; P =.55). There was a strong correlation between CPAP pressure and improvement in nGER score (correlation, r = 0.70; P<.001), with patients with higher CPAP pressures demonstrating a greater improvement in nGER score.

CONCLUSIONS: Nocturnal GER is common in patients with OSA. Treatment with nasal CPAP decreases the frequency of nGER symptoms by 48%. Higher nasal CPAP pressures are associated with greater improvement in nGER.