Obstructive Sleep Apnea (OSA) is common in modern society, affecting up to 5% of working middle-aged adults in the United States. Obesity is the number one risk factor for the development of OSA. Consequences of untreated OSA are varied and significant and included numerous neuropsychiatric parameters such as mood alterations, depression, anxiety, diminished social interactions, and decreased quality of life. Mounting evidence suggests that treatment of OSA can improve many of these outcomes. The primary treatment modality for this condition is continuous positive airway pressure (CPAP). This device delivers positive pressure to the upper airway in order to prevent its collapse during sleep. Unfortunately, many patients do not choose to use CPAP or have difficulty with these devices. This results in many individuals with OSA either going without therapy or unable to reap the full benefits of treatment.

Gastroesophageal reflux (GERD) is also common in the United States and may, in some instances, be directly related to weight gain. Survey studies have suggested that symptomatic GERD is more common in patients with OSA. Whether there exists a cause and effect relationship between these two conditions is not known at present. It has been suggested that GERD may contribute to OSA by narrowing the upper airway.

This study will examine the effect of treatment of GERD on mild to moderate OSA. Fifty individuals identified as having mild to moderate OSA (diagnosed by overnight sleep study or PSG) and GERD (confirmed by an esophageal probe) will be enrolled. Both men and women will be included in this study and no

• special populations” will be utilized. Subjects will fill out questionnaires to subjectively measure sleepiness, OSA-related symptoms, GERD-related symptoms, and sleep apnea-related quality of life. They will then be randomized to receive either 12 weeks of the proton pump inhibitor lansoprazole (Prevacid) or placebo (twenty five subjects per group). Upon completion of the 12 week trial, subjects will return and the following data will be collected; repeat all of the baseline questionnaires, repeat PSG and repeat pH probe.

Results from this study will help to establish the relative effectiveness of a novel form of therapy for a common yet difficult to manage medical condition. . The risks to subjects enrolled in the study are minimal and therefore the benefit to risk ratio is heavily in favor of performing the study.