Experiences of a sleep disorders center: 1700 patients later.

Sleep studies reveal many patients to have specific sleep abnormalities different from what might be suspected from the clinical history. For example, in our experience, patients who were later found to have central sleep apnea presented with chief complaints of excessive sleepiness or insomnia. In patients requesting evaluation for sleep apnea, screening studies that detect only sleep-disturbed breathing (ie, oximetry) may miss other diagnoses in one fourth of cases.