The impact of experimentally shortened sleep on timing of eating occasions in adolescents: A brief report.

Short sleep increases the risk for obesity in adolescents. One potential mechanism relates to when eating occurs in the day. This study investigated the impact of shortened sleep on eating occasion timing in adolescents. Ninety-three healthy 14- to 17-year-olds (62% female) completed a within-subject experimental sleep manipulation, engaging in 5-night spans of Short Sleep (6.5-hr sleep opportunity) or Healthy Sleep (9.5-hr sleep opportunity), with order randomized. During each condition, adolescents completed three 24-hr diet recall interviews. Repeated-measure t-tests assessed the sleep manipulation effect on each adolescent's number of meals, first and last eating occasion (relative to the clock and time since sleep onset/offset), feeding window (timespan from first to last eating), and the midpoint of feeding. The timing of the first eating occasion was similar across conditions, relative to the clock (Short = 08:51, Healthy = 08:52) and to time since waking (Short = 2.0 hr, Healthy = 2.2 hr). The timing of the last eating occasion was later relative to the clock (Short = 20:34, Healthy = 19:39; p < 0.001), resulting in a longer feeding window (Short = 11.7 hr, Healthy = 10.8 hr, p < 0.001) and a later midpoint in the feeding window (Short = 14:41, Healthy = 14:18, p = 0.002). The gap between last eating occasion and sleep onset was larger in Short (4.2 hr) than Healthy Sleep (2.9 hr; p < 0.001), though the last eating occasion was much earlier than when they fell asleep during either condition. Shortened sleep resulted in adolescents eating later and lengthening the daily feeding window. These findings may help explain the link between shortened sleep and increased obesity risk in adolescents.

The impact of short sleep on food reward processes in adolescents.

Short sleep has been linked to adolescent risk of obesity, but questions remain regarding the dietary mechanisms by which this occurs. We tested whether mildly shortening sleep influences how rewarding and appealing healthy adolescents find several kinds of foods. Eighty-eight healthy adolescents completed a within-subjects crossover sleep experiment comparing 5 days of Short Sleep (6.5 hr sleep opportunity) with 5 days of Healthy Sleep (9.5 hr sleep opportunity). Following each condition, adolescents completed measures of food appeal and reinforcing value of food across five food types: sweets/desserts, fruits/vegetables, lean meats/eggs, fast food and processed snacks. Adolescents averaged 2.2 hr/night longer sleep periods in Healthy Sleep versus Short Sleep. We observed a significant interaction of experimental order with sleep condition on three of four primary outcomes related to the appeal and reinforcing value of foods (p's < .005). When Short Sleep preceded Healthy Sleep, adolescents endorsed significantly greater appeal (p < .04) and rewarding value of food (p's ranging from <.01 to .048) during Short Sleep (compared to Healthy Sleep). However, when Healthy Sleep preceded Short Sleep, we did not observe a main effect of sleep condition on the same outcomes (p's > .05). This study provides evidence that restricting adolescents' sleep opportunity to 6.5 hr (compared to sleeping a healthy amount) increases the appeal and reinforcing value of a variety of foods, but this may occur only under protracted short sleep. Increased food reward may be one mechanism linking chronically shortened sleep with risk of obesity in adolescence.

2010 American College of Rheumatology Adult Fibromyalgia Criteria for Use in an Adolescent Female Population with Juvenile Fibromyalgia.

OBJECTIVES: To evaluate the utility of the 2010 American College of Rheumatology (ACR) adult fibromyalgia criteria for use in adolescents with juvenile fibromyalgia (JFM). STUDY DESIGN: Participants included 47 adolescent girls diagnosed with JFM (mean age = 15.3 years) and 48 age- and sex-matched adolescents (mean age = 15.0 years) with localized chronic pain (eg, headaches or abdominal pain). A trained examiner administered the Widespread Pain Index and Symptom Severity measures and also completed a manual tender point exam. Clinicians completed a form indicating the presence of active JFM per Yunus and Masi (1985) criteria, the only available and most commonly used measure for JFM. Criterion validity analysis was performed as well as t tests comparing symptoms between JFM and controls. RESULTS: With the Yunus and Masi criteria used as the gold standard, the 2010 ACR fibromyalgia criteria showed a sensitivity of 89.4% and specificity of 87.5%. CONCLUSION: The 2010 ACR measure appears to be a valuable tool for the identification of JFM. However, a slight modification to the 2010 ACR measure and inclusion of a clinical exam is recommended.

Losing sleep by staying up late leads adolescents to consume more carbohydrates and a higher glycemic load.

This study examined how short sleep impacts dietary consumption in adolescents by testing whether experimentally shortening sleep influences the amount, macronutrient content, food types, and timing of food consumed. Ninety-three adolescents completed a within-subjects crossover paradigm comparing five nights of short sleep (6.5-hour sleep opportunity) to five nights of Healthy Sleep (9.5-hour sleep opportunity). Within each condition, adolescents completed three multiple-pass dietary recalls that recorded the types, amount, and timing of food intake. The following outcomes were averaged across days of dietary recall within condition: kilocalories, grams of carbohydrates, fat, protein, and added sugars, glycemic load of foods, and servings of specific types of foods (low-calorie drinks, sweetened drinks, fruits/vegetables, meats/proteins, processed snacks, "fast food" entrees, grains, and sweets/desserts). Timing of consumption of kilocalorie and macronutrient outcomes were also examined across four noncumulative time bins: 06:00-10:59, 11:00-15:59, 16:00-20:59, and 21:00-01:00. Adolescents slept 2 h and 20 min longer in Healthy Sleep than in Short Sleep (p < .0001). While in Short Sleep, adolescents ate more grams of carbohydrates (p = .031) and added sugars (p = .047), foods higher in glycemic load (p = .013), and servings of sweet drinks (p = .023) and ate fewer servings of fruits/vegetables (p = .006) compared to Healthy Sleep. Differences in consumption of kilocalories, fat, and carbohydrates emerged after 9:00 pm (ps = .012, .043, .006, respectively). These experimental findings suggest that adolescents who have insufficient sleep exhibit dietary patterns that may increase the risk for negative weight and cardiometabolic outcomes. Future health promotion efforts should include promoting optimal sleep to increase healthy dietary habits.

Feasibility and impact on daytime sleepiness of an experimental protocol inducing variable sleep duration in adolescents.

Although most research on sleep and adolescent health has focused on how long each youth sleeps on average, variability in sleep duration may be just as problematic. Existing findings have been inconsistent and unable to address cause-effect relationships. This study piloted an experimental protocol to induce sleep variability and explore its impact on daytime sleepiness in adolescents. Healthy adolescents aged 14-17 participated in a 3-week, at-home protocol. Sleep was monitored by sleep diaries and actigraphy. Following a run-in period to stabilize wake times (set at 6:30am throughout the protocol), participants were randomly counterbalanced across two 5-night experimental conditions. Bedtimes were consistent at 11:00pm during the stable sleep condition (7.5-hour sleep period each night) but changed on alternating nights during the variable sleep condition (ranging from 9:30pm to 12:30am) so that sleep duration averaged 7.5 hours across the condition with a standard deviation of 1.37 hours. Difficulty waking was assessed each morning and daytime sleepiness was assessed by end-of-condition parent- and adolescent-reports. Of the 20 participants who completed the study, 16 met the predetermined adherence definition. For those who were adherent, there were no differences in overall sleep duration between the stable and variable sleep conditions (p>.05) but adolescents had 58.6 minutes greater night-to-night variation in sleep duration in the variable condition (p < .001). Across all nights, youth reported greater difficulty waking following nights of shorter assigned sleep (p = .004) and greater overall sleepiness during the variable condition (p = .03). It is feasible to experimentally vary how long adolescents sleep on a nightly basis while holding average sleep duration constant. Such a protocol will promote tests of the acute effects of day-to-day changes in sleep duration on health.

Inducing more sleep on school nights reduces sedentary behavior without affecting physical activity in short-sleeping adolescents.

OBJECTIVES/BACKGROUND: Short sleep duration during adolescence is associated with increased dietary intake and greater risk for overweight/obesity. However, findings are mixed on the relationship between sleep and physical activity (PA) during the school year, when short sleep duration is most common. Furthermore, there is concern that increasing sleep duration may interfere with opportunities for PA, yet this has not been directly tested. This study examined the impact of an at-home experimental sleep extension protocol on PA during the school year among short-sleeping adolescents. PARTICIPANTS/METHODS: Participants included 18 adolescents (67% female, 78% white) who reported regularly sleeping between 5-7 h on school nights. Adolescents completed a five-week, at-home sleep manipulation protocol with an initial baseline week followed in a randomized, counterbalanced order by two experimental conditions, each lasting two weeks. During prescribed habitual sleep (HAB), bedtimes and rise times were set to match the baseline sleep pattern, and during sleep extension (EXT), adolescents were instructed to increase time in bed on school nights by 1.5 h per night relative to baseline. Wrist-mounted actigraphy was employed to monitor sleep and waist-mounted accelerometers were used to measure daytime PA. RESULTS: Adolescents slept for an average duration of 71 min longer on school nights during EXT than during HAB (p < 0.001). During HAB, adolescents spent more time in sedentary behavior (p = 0.002) than during EXT, but there were no cross-condition differences in light activity (p = 0.184) or moderate-to-vigorous PA (p = 0.102). CONCLUSIONS: Extending sleep duration on school nights in short-sleeping adolescents reduces time spent in sedentary behavior, without having a negative impact on health-promoting moderate-to-vigorous PA.

Feasibility and Emotional Impact of Experimentally Extending Sleep in Short-Sleeping Adolescents.

Study Objectives: Published experimental sleep manipulation protocols for adolescents have been limited to the summer, limiting causal conclusions about how short sleep affects them on school nights, when they are most likely to restrict their sleep. This study assesses the feasibility and emotional impact of a school-night sleep manipulation protocol to test the effects of lengthening sleep in habitually short-sleeping adolescents. Methods: High school students aged 14-18 years who habitually slept 5-7 hours on school nights participated in a 5-week experimental sleep manipulation protocol. Participants completed a baseline week followed in randomized counterbalanced order by two experimental conditions lasting 2 weeks each: prescribed habitual sleep (HAB; sleep time set to match baseline) and sleep extension (EXT; 1.5-hour increase in time in bed from HAB). All sleep was obtained at home, monitored with actigraphy. Data on adherence, protocol acceptability, mood and behavior were collected at the end of each condition. Results: Seventy-six adolescents enrolled in the study, with 54 retained through all 5 weeks. Compared to HAB, during EXT, participants averaged an additional 72.6 minutes/night of sleep (p < .001) and had reduced symptoms of sleepiness, anger, vigor, fatigue, and confusion (p < .05). The large majority of parents (98%) and adolescents (100%) said they would "maybe" or "definitely" recommend the study to another family. Conclusions: An experimental, school-night sleep manipulation protocol can be feasibly implemented which directly tests the potential protective effects of lengthening sleep. Many short-sleeping adolescents would benefit emotionally from sleeping longer, supporting public health efforts to promote adolescent sleep on school nights.