Sleep and cognitive decline: A prospective nondemented elderly cohort study

To investigate sleep disturbances that induce cognitive changes over 4 years in nondemented elderlies.Data were acquired from a nationwide, population-based, prospective cohort of Korean elderlies (2,238 normal cognition [NC] and 655 mild cognitive impairment [MCI]). At baseline and 4-year follow-up assessments, sleep-related parameters (midsleep time, sleep duration, sleep latency, subjective sleep quality, sleep efficiency, and daytime...