Predictors of obstructive sleep apnea on a home sleep apnea test after a negative attended polysomnography

Study Objectives: A home sleep apnea test (HSAT) is an acceptable alternative to polysomnography (PSG) for the diagnosis of obstructive sleep apnea (OSA) in patients with high pretest probability without certain comorbidities, such as severe pulmonary disease, congestive heart failure, or neuromuscular weakness. Current guidelines recommend repeat in-laborataory PSG in those with an initial negative PSG and high clinical suspicion for OSA. This retrospective study evaluated predictors of OSA on HSAT in patients who had a negative PSG. Methods: Electronic medical records were reviewed on 206 patients who underwent an in-laboratory PSG followed by HSAT at the Baylor Scott and White Sleep Institute. Of these patients, 141 were included in the study. Clinical patient characteristics, PSG data, and HSAT data were obtained. Results: A total of 141 patients had a negative PSG and underwent a subsequent HSAT. Of these patients, 83.7% had a positive diagnosis on HSAT, as defined by respiratory event index greater than or equal to 5 events/h, using the 4% oxygen desaturation criteria, (64.5% mild, 17.7% moderate, 1.4% severe) and 16.3% had a negative HSAT. Older age and hypertension predicted the diagnosis of OSA made on HSAT in patients with an initial negative PSG. Conclusions: This retrospective study illustrates that there are patients for whom PSG gave a false-negative study. Patients who had negative PSG and positive HSAT are more likely to be older and have the diagnosis of hypertension. Sleep physicians may consider repeat testing with HSAT in patients with a negative PSG and clinical symptoms of OSA.