MedicalResearch.com Interview with:
Nathaniel F. Watson, MD, MSc
Professor of Neurology, University of Washington
Co-director, University of Washington Medicine Sleep Center
Director, Harborview Medical Center Sleep Clinic
MedicalResearch: What are the main findings of the study?
Dr. Watson: The Singh Index is a composite measure of socioeconomically deprived neighborhoods. We found that as Singh Index increased, sleep duration reduced. This was true in the total sample of twins, and within twin pairs. The fact that we saw this within twin pairs means the association is present after controlling for genetics and shared environment, which substantially strengthens the association.
MedicalResearch: Were any of the findings unexpected?
Dr. Watson: We also found a gene by environment interaction. As Singh Index went up, the total genetic and non-shared environmental variability of sleep duration also went up. So the more socioeconomically deprived the neighborhood, the more erratic the sleep duration, both shorter and longer then the healthy 7-9 hours per night that we recommend.
MedicalResearch: What should clinicians and patients take away from your report?
Dr. Watson: These results are a starting point for discussing the impact that neighborhood level factors have on sleep duration. If we improve upon social deprivation, we may have an opportunity to improve upon sleep habits that influence how long people sleep.
MedicalResearch: What recommendations do you have for future research as a result of this study?
Dr. Watson: We need to assess more specific individual measures of the impact of built environment, such as noise and pollution sensors and activity monitors, to more specifically assess the particular aspects of neighborhood deprivation that impact sleep length.