The consensus sleep diary: quantitative criteria for primary insomnia diagnosis.

OBJECTIVE: The aim of the study was to put forward quantitative criteria for the Consensus Sleep Diary, to differentiate people with insomnia from normal sleepers. METHODS: In this retrospective study, we analyzed 295 sleep diaries of patients with primary insomnia (43% were male, ages ranging between 17 and 76 years) collected in two clinical centers for insomnia and 536 sleep diaries of normal sleepers (47% were male, ages ranging between 15 and 82 years). We considered the following sleep parameters: time in bed, sleep onset latency, total sleep time, wake after sleep onset, sleep efficiency, number of awakenings, terminal wakefulness, and subjective feeling of rest. Using the Youden index, we calculated the quantitative criteria that performed best for each sleep parameter. Finally, we created receiver operating characteristic curves to test the accuracy of each identified criterion. RESULTS: Individuals with insomnia significantly differed from controls on all sleep indices (p < .001). Differentiation between individuals with insomnia from controls was optimal for terminal wakefulness (>15 minutes, area under the curve [AUC] = 0.83), wake after sleep onset (cutoff >20 minutes, AUC = 0.81), total sleep time (<390 minutes, AUC = 0.80), and particularly sleep efficiency (<87.5%, AUC = 0.92, sensitivity = 0.80, specificity = 0.90). Time in bed was the least differentiating variable (<500 minutes, AUC = 0.57). CONCLUSIONS: The quantitative criteria of the sleep diary in this study agree with the few available data in the literature. This confirms that the sleep diary could be a useful screening tool for assessing patients with primary insomnia.

Effects of dawn simulation on attentional performance in adolescents.

PURPOSE: This study aimed at examining the effects of 2 weeks of dawn simulation on attentional performance in adolescents. METHODS: On the whole, 56 adolescents (24 females and 32 males) took part to the study, with a mean age of 17.68 ± 0.97 years (age ranging between 15 and 20 years). Each adolescent was requested to participate for 5 consecutive weeks and the research design included the baseline and two counterbalanced conditions, dawn simulator and control (no dawn simulator). Attentional performance of adolescents was measured through the attention network test (ANT) that allowed assessing the efficiency of three separable attentional networks, namely alerting, orienting and executive. Overall, participants performed the ANT three times (i.e., one time for each condition), while sleep quality, sleep duration and sleep timing were concurrently monitored by means of actigraphy and were treated as potential confounders. RESULTS: The only improvement of the attentional performance attributable to the use of dawn simulator was observed for the efficiency of alerting network (45.97 ± 32.76 ms) that significantly increased in comparison to the baseline (31.57 ± 26.97 ms) (p < 0.05). On the contrary, the sleep quality, sleep quantity and sleep timing did not significantly change. CONCLUSION: These results show for the first time that, controlling for sleep quality, sleep duration and sleep timing, the use of dawn simulator across 2 weeks is able to determine an alerting effect in adolescents.

Association between seasonal affective disorder and subjective quality of the sleep/wake cycle in adolescents.

The relationship between seasonal affective disorder (SAD) and subjective quality of sleep/wake cycle in adolescents was explored. The Seasonal Pattern Assessment Questionnaire for Children and Adolescents (SPAQ-CA) and Mini Sleep Questionnaire (MSQ) were administered to 345 adolescents living in the city of Cesena (Emilia-Romagna region, Italy) (299 females; age range: 14-18 years), to determine SAD and perceived quality of the sleep/wake cycle. The response rate was 92% for females and 90.2% for males. The MSQ includes two factors, sleep and wake, with lower scores corresponding to a lower quality of sleep and wake. The MSQ includes cut-off criteria to detect a good or bad sleep and wake quality. Adolescents with SAD (16 ± 5.7) scored significantly lower than those not affected on wake factor (19.5 ± 4.3), while no effect has been observed on sleep factor. SAD was the only one significant predictor of good/bad wake quality, while it did not reach significant level with reference to good/bad sleep quality. Present results are indications of a possible influence of SAD on wake quality and further studies are necessary to confirm them.

The role of actigraphy in the assessment of primary insomnia: a retrospective study.

OBJECTIVE: The aim of our study was to evaluate quantitative actigraphic criteria obtained using the Actiwatch device (AW64; Cambridge Neurotechnology Ltd., Cambridge, UK) to differentiate participants with insomnia from normal sleepers. METHODS: In our retrospective study, we recovered 493 actigraphic records from two sleep measure databases of patients with insomnia (n=151) and one of normal sleepers (n=342). We considered the following actigraphic sleep parameters: time in bed (TIB), sleep-onset latency (SOL), total sleep time (TST), wake after sleep onset (WASO), sleep efficiency (SE), number of awakenings (NWAK), terminal wakefulness (TWAK), fragmentation index (FI), and mean motor activity (MA). We also considered two actigraphic circadian indexes: interdaily stability and intradaily variability. Using the Youden index, we calculated the quantitative actigraphic criteria that performed best for each actigraphic sleep parameter. Finally, we created receiver operating characteristic curves to test the accuracy of each criterion identified. RESULTS: All sleep parameters except TST and TWAK differentiated the two groups of participants, allowing calculation of quantitative actigraphic criteria. There were no differences in the circadian indices. CONCLUSIONS: The quantitative actigraphic criteria obtained in our study were not the same as those obtained previously with a different device, suggesting the need to adopt shared technical solutions for actigraphy.

Effects of transitions into and out of daylight saving time on the quality of the sleep/wake cycle: an actigraphic study in healthy university students.

The main goal of the present study was to examine the effects of transition into and out of daylight saving time (DST) on the quality of the sleep/wake cycle, assessed through actigraphy. To this end, 14 healthy university students (mean age: 26.86 ± 3.25 yrs) wore an actigraph for 7 d before and 7 d after the transition out of and into DST on fall 2009 and spring 2010, respectively. The following parameters have been compared before and after the transition, separately for autumn and spring changes: bedtime (BT), get-up time (GUT), time in bed (TIB), sleep onset latency (SOL), fragmentation index (FI), sleep efficiency (SE), total sleep time (TST), wake after sleep onset (WASO), mean activity score (MAS), and number of wake bouts (WB). After the autumn transition, a significant advance of the GUT and a decrease of TIB and TST were observed. On the contrary, spring transition led to a delay of the GUT, an increase of TIB, TST, WASO, MAS, and WB, and a decrease of SE. The present results highlight a more strong deterioration of sleep/wake cycle quality after spring compared with autumn transition, confirming that human circadian system more easily adjusts to a phase delay (autumn change) than a phase advance (spring transition).