1 Department of Neurology- Baystate Medical Center, University of Massachusetts Medical School-Baystate, Springfield, MA, USA karin.johnson@baystatehealth.org.
2 Department of Family, Population, and Preventive Medicine, Renaissance School of Medicine, Stony Brook University, NY, USA.
3 Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA karin.johnson@baystatehealth.org.
4 Sleep Disorders Division, Department of Neurology, Vanderbilt University School of Medicine, Nashville, TN, USA.