Acute and long-term sleep measurements produce opposing results on sleep quality in 8 and 12 hour shift patterns in law enforcement officers

The occupational demands of law enforcement increase the risk of poor-quality sleep, putting officers at risk of adverse physical and mental health. This cross-sectional study aimed to characterise sleep quality in day workers, 8 and 12 h rotating shift pattern workers. One hundred eighty-six officers volunteered for the study (37 female, age: 41 ± 7). Sleep quality was assessed using the Pittsburgh sleep quality index, actigraphy and the Leeds sleep evaluation questionnaire. The maximal aerobic capacity (VO2max ) was measured on a treadmill via breath-by-breath analysis. There was a 70% overall prevalence of poor sleepers based on Pittsburgh sleep quality index scores, where 8 h shifts exhibited the worst prevalence (92%, p = 0.029), however, there was no difference between age, gender, or role. In contrast, 12 h shifts exhibited the poorest short-term measures, including awakening from sleep (p = 0.039) and behaviour following wakefulness (p = 0.033) from subjective measures, and poorer total sleep time (p = 0.024) and sleep efficiency (p = 0.024) from the actigraphy. High VO2max predicted poorer wake after sleep onset (Rsq = 0.07, p = 0.05) and poorer sleep latency (p = 0.028). There was no relationship between the Pittsburgh sleep quality index scores and any of the short-term measures. The prevalence of poor sleepers in this cohort was substantially higher than in the general population, regardless of shift pattern. The results obtained from the long- and short-term measures of sleep quality yielded opposing results, where long-term perceptions favoured the 12 h pattern, but short-term subjective and objective measures both favoured the 8 h pattern.

Effects of Saffron Extract on Sleep Quality: A Randomized Double-Blind Controlled Clinical Trial

A saffron extract has been found to be effective in the context of depression and anxiety, but its effect on sleep quality has not been investigating yet using objective approaches. For this purpose, a randomized double-blind controlled study was conducted in subjects presenting mild to moderate sleep disorder associated with anxiety. Sixty-six subjects were randomized and supplemented with a placebo (maltodextrin) or a saffron extract (15.5 mg per day) for 6 weeks. Actigraphy was used to collect objective data related to sleep quality at baseline, at the middle and at the end of the intervention. Sleep quality was also assessed by completion of the LSEQ and PSQI questionnaires and quality of life by completion of the SF-36 questionnaire. Six weeks of saffron supplementation led to an increased time in bed assessed by actigraphy, to an improved ease of getting to sleep evaluated by the LSEQ questionnaire and to an improved sleep quality, sleep latency, sleep duration, and global scores evaluated by the PSQI questionnaire, whereas those parameters were not modified by the placebo. In conclusion, those results suggest that a saffron extract could be a natural and safe nutritional strategy to improve sleep duration and quality.

Validation of the adapted Leeds sleep evaluation questionnaire in Ethiopian university students

Background

Current evidence supports the applicability of the Leeds Sleep Evaluation Questionnaire (LSEQ) in screening for insomnia. The psychometric properties of the LSEQ have never been investigated in an African population. Therefore, this study aimed to validate the adapted version of the LSEQ-Mizan (LSEQ-M) in Ethiopian university students.

Methods

Of a preliminary sample of 750 (random sampling), 424 students (age = 21.87 ± 4.13 years and body mass index = 20.84 ± 3.18 kg/m²) from Mizan-Tepi University, Mizan-Aman, South-west Ethiopia completed the LSEQ-M, the General Anxiety Disorder Scale-7 and a semi-structured questionnaire for socio-demographics. Insomnia was screened in accordance with the International Classification of Sleep Disorders as a measure of concurrent validity.

Results

Although, individual items showed ceiling and floor effect, the LSEQ-M as a scale did not have these effects. Good internal consistency (Cronbach’s alpha of 0.84) and strong internal homogeneity as measured by the correlation coefficient between items scores and the LSEQ-M global score was found. The LSEQ-M showed excellent screening applicability for insomnia with optimal cut-off scores of 52.6 (sensitivity 94%, specificity 80%), and the area under the curve, 0.95 (p < 0.0001). The original 4-Factor model was valid in Ethiopian university students for screening for insomnia.

Conclusion

The LSEQ-M has excellent psychometric validity in screening for insomnia among Ethiopian university students.

Electronic supplementary material

The online version of this article (10.1186/s12955-018-0876-0) contains supplementary material, which is available to authorized users.