1. Department of Internal Medicine, Mayo Clinic, 13400 E Shea Blvd, Scottsdale, AZ 85259, USA
2. Department of Sleep Disorders & Pulmonology, Mayo Clinic, 13400 E Shea Blvd, Scottsdale, AZ 85259, USA
3. Division of Cardiovascular Diseases, Mayo Clinic, 13400 EShea Blvd, Scottsdale, AZ 85259, USA
4. Department of Family Medicine, Mayo Clinic, 13400 E Shea Blvd, Scottsdale, AZ 85259, USA