Social Jetlag and Excessive Daytime Sleepiness from a Sample of Russian Children and Adolescents

PURPOSE: Insufficient nocturnal sleep is a primary source of excessive daytime sleepiness. Most previous research has focused on the disparity between sleep demands and study start times in adolescents. Fewer studies have focused on elementary schoolchildren. We hypothesize that late sleep timing is connected to excessive daytime sleepiness in a sample of Russian children and adolescents. The major goals of our study were to evaluate excessive daytime sleepiness in Russian schoolchildren and adolescents using the Russian version of the Pediatric Daytime Sleepiness Scale (PDSS) and to estimate its relationship with sleep-wake parameters using the Munich Chronotype Questionnaire (MCTQ). MATERIALS AND METHODS: Student subjects were from public educational facilities in the Republic of Karelia. They completed both the PDSS and the Munich Chronotype Questionnaire to estimate sleep parameters and chronotype (MSFsc). Five hundred and eleven students provided data for the PDSS and sleep-wake variables, and 479 for the full MCTQ data. RESULTS: The overall prevalence of Excessive Daytime Sleepiness (EDS) in our sample was 18%. The total PDSS score was inversely correlated with sleep length on school nights and was independent of respondents\u27 sex. Higher PDSS scores were associated with later bedtimes on school days and free days, and shorter sleep duration on school days. Late chronotype and more pronounced social jetlag were both positively correlated with high PDSS scores. A negative correlation was found between chronotype and the duration of the sleep period on weekdays (p \u3c 0.001) and a positive correlation was found on weekends (p \u3c 0.001). Longer average sleep duration was positively related to less daytime sleepiness. CONCLUSION: This study suggests that excessive daytime sleepiness is chronotype-dependent. School start times could be shifted to a later hour to prolong sleep and reduce EDS

Circadian Factors in Stroke: A Clinician’s Perspective

Abstract Stroke remains one of the leading causes of mortality and long-term and permanent disability worldwide despite technological innovations and developments in pharmacotherapy. In the last few decades, the growing data have evidenced the role of the circadian system in brain vulnerability to damage, the development and evolution of stroke, and short-term and long-term recovery. On the other hand, the stroke itself can affect the circadian system via direct injury of specific brain structures involved in circadian regulation (i.e., hypothalamus, retinohypothalamic tracts, etc.) and impairment of endogenous regulatory mechanisms, metabolic derangement, and a neurogenic inflammatory response in acute stroke. Moreover, the disruption of circadian rhythms can occur or exacerbate as a result of exogenous factors related to hospitalization itself, the conditions in the intensive care unit and the ward (light, noise, etc.), medication (sedatives and hypnotics), and loss of external factors entraining the circadian rhythms. In the acute phase of stroke, patients demonstrate abnormal circadian variations in circadian biomarkers (melatonin, cortisol), core body temperature, and rest–activity patterns. The approaches aimed at the restoration of disrupted circadian patterns include pharmacological (melatonin supplementation) and non-medication (bright light therapy, shifting feeding schedules, etc.) interventions; however, their effects on short- and long-term recovery after stroke are not well understood