Clinical and Psg Predictors of the Natural History of Poor Sleep

689 Natural History of Poor Sleep—Fernandez-Mendoza et al cently reported that poor sleep with objective short sleep duration is a risk factor for hypertension.6 Moreover, poor sleep is an independent risk factor for the development of chronic insomnia,7 which is associated with significant medical morbidity6,8-10 and mortality.11 Together, these findings suggest that poor sleep is a very prevalent condition whose medical effect has been underestimated. Very little is known about the incidence and persistence of insomnia symptoms or poor sleep, with 2 studies suggesting rates of approximately 30% and 46%, respectively.12,13 Even less is known about the risk factors involved in the natural history of poor sleep in the general population. Furthermore, no study to date has explored the role of polysomnographic (PSG) variables, such as sleep apnea or sleep duration, in the natural history of poor sleep. The 3 objectives of this study were to examine the risk factors involved in the incidence of poor sleep, the persistence of poor sleep, and the evolution of poor sleep into chronic insomnia in a large general random sample (the Penn State Cohort Study) using both subjective and objective (i.e., PSG) data and a longitudinal design.