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It is estimated that 40% of the US population suffers from at least one chronic health condition such as heart disease or diabetes (National Center for Health Statistics, 2011). Truncated physical activity (Center for Disease Control and Prevention, 2011) and insufficient sleep (Liu, 2004), both of which are modifiable health behaviors, have been associated with increased risk for chronic diseases (Liu, 2004) and mortality (Kung, Hoyert, Xu, & Murphy, 2008). Insufficient sleep and short sleep duration are associated with obesity (Robert D. Vorona et al., 2005), incident diabetes (Gangwisch et al., 2007), and hypertension and cardiovascular risk (Buxton & Marcelli, 2010; Knutson, 2010).
Few adolescents sleep an optimal nine hours per night (M. Carskadon, Acebo, & Jenni, 2004), and high school students exhibit a high prevalence of sleep health problems (Ming et al., 2011). Insufficient sleep and inconsistent sleep patterns among adolescents are unhealthy sleep behaviors. Unhealthy sleep behaviors are associated with truancy (Pasch, Laska, Lytle, & Moe, 2010), depression, and substance use (McKnight-Eily et al., 2011; Pasch et al., 2010), decreased physical activity (McKnight-Eily et al., 2011), obesity (M. Carskadon, Vieira, & Acebo, 1993; Drescher, Goodwin, Silva, & Quan, 2011), poor grades (Perkinson-Gloor, Lemola, & Grob, 2013), and diminished cognitive function (Ferrie et al., 2011). The development of healthy sleep during childhood and adolescence is important to the sustainment of healthy behaviors into early adulthood (Brener & Collins, 1998; Tobler & Stratton, 1997). Interventions designed to alter unhealthy sleep-related behaviors adopted at an early age may have a salubrious impact upon later chronic disease (e.g., Wilfley et al. (2007)). Thus, studying the progression from behavior to adverse outcomes may have significant public health implications.
An understanding of the risk factors operating during the vulnerable period of transition from childhood to adolescence (Dekovic, 1999; Fischhoff, Nightingale, & Iannotta, 2001) through high school (Diaz, Szklo-Coxe, Behr, & Toba, 2012; Diaz, Szklo-Coxe, & Behr, 2012; Roberts, Roberts, & Xing, 2010) may allow for the identification of interventions that promote healthy sleep and longer-term positive health outcomes ((Contoyannis & Jones, 2004; Lerner & Galambos, 1998), see also (Moseley & Gradisar, 2009)). Developmental sleep changes and phase delays of the circadian system impact sleep-wake timing in adolescents (M. Carskadon et al., 1993; Owens, Belon, & Moss, 2010). Adolescents are at risk for poor or insufficient sleep due to early school start times (Lufi, Tzischinsky, & Hadar, 2011). Early school start times have been related to both sleep deprivation and daytime sleepiness as adolescents go to bed later, yet may still rise early due to school start times (M. A. Carskadon, Wolfson, Acebo, Tzischinsky, & Seifer, 1998). Increased crash rates in adolescents have also been reported in cities with earlier, versus later, high school start times (Robert Daniel Vorona, Szklo-Coxe, Wu, Dubik, & Zhao, 2011).