Sleep-Wake Cycle of Adolescents in Côte d'Ivoire: Influence of Age, Gender, Religion and Occupation

Evening type negatively affects semen quality by deteriorating sperm morphology: Results from an infertility clinic

OBJECTIVE

The effect of sleep-related variables on the reproductive system has garnered attention in recent years. One of the mediators that reportedly plays an important role in the relationship between sleep disorders and the reproductive system is a disruption of the circadian rhythm. The aim of curent study is to investigate the effect of chronotype on morning semen quality.

STUDY DESIGN

Three-hundred and fourteen patients who applied to the infertility clinic were included in the study. The patients filled a socio-demographic data form. The "Pittsburg Sleep Quality Index (PSQI) was used to evaluate the sleep quality while the chronotypes of the patients were evaluated with the "Morningness -Eveningness-Questionnaire (MEQ)". Semen analyses and biochemical analysis for testosterone serum plasma level of all patients were performed.

RESULTS

Twenty-one patients were assigned as evening, 187 patients were assigned as intermediate, and 106 were assigned as morning chronotype. No statistically significant difference was identified in the comparison of the mean MEQ scores between patients with low and normal sperm concentrations(p = 0.884). A correlation analysis indicated the presence of a significant positive correlation between normal morphology and MEQ scores (r = 0.13, p < 0.05) and a negative corelation between the hours spent in bed and sperm concentration (r = -0.13, p < 0.05). A general linear model created with independent variables suggested that the presence of varicocele and MEQ scores had a significant effect on normal morphology.

CONCLUSION

The results of present study support that evening type could negatively affect sperm morphology; additionally, the time spent in bed also negatively affected sperm concentration.

Factors Underpinning the Shift to Eveningness during Early Adolescence: Pubertal Development and Family Conflicts

Biological and psychosocial factors have been related to the shift to eveningness during early adolescence but it is necessary to study them from a longitudinal perspective. This longitudinal study examined the contribution of these factors to the onset of a shift towards eveningness in early adolescence. A sample of 440 (49.9% boys) Spanish adolescents were assessed for pubertal development, family conflicts, and morningness/eveningness. The same measures were taken twice at the age of 12 and one year later (T1: M = 12.47, SD = 0.75 and T2: M = 13.64, SD = 0.78). Pubertal development and family conflicts were considered predictors of morningness/eveningness in a mixed-effects multilevel model. The developmental shift towards eveningness appeared in girls but not in boys. The shift was related to more advanced pubertal development and more conflicts in the family. This study has implications for shaping healthy sleep habits in adolescents and possible interventions focused on family dynamics.

Sex differences in sleep patterns and changes in 7th to 12th graders: a longitudinal follow-up study in Taiwan

Study Objectives

To assess the relationship between sex and the development of sleep patterns in adolescents from grade 7 to 12.

Methods

We analyzed longitudinal data from annual school-based assessments of sleep habits among secondary school students in northern Taiwan. Measures of sleep patterns included sleep length on weekdays and weekends as well as weekend-weekday difference (WndD), defined as the discrepancy in the time in bed (TIB) between weekdays and weekends. Growth curve models were used to assess sex differences in sleep patterns. Associations between other covariates and sleep patterns were also explored.

Results

We found shorter weekday TIB in girls compared with boys at all time points. In contrast, girls had longer weekend TIB than boys over time except in the 12th grade. WndD was also longer in girls than boys. All interaction terms between sex and time were insignificant, indicating that developmental change across time was not statistically different for boys and girls. Several other factors, namely, parental education, pubertal development, self-perceived health, weight status, depressive symptoms, academic stress, infrequent exercise, and substance use, were also found to be associated with sleep patterns.

Conclusions

Our findings show a sex difference in TIB both on weekdays and weekends. No sex difference was found in the development of sleep patterns over time.

Characteristics Associated with Sleep Duration, Chronotype, and Social Jet Lag in Adolescents

Sleep is a complex behavior with numerous health implications. Identifying sociodemographic and behavioral characteristics of sleep is important for determining those at greatest risk for sleep-related health disparities. In this cross-sectional study, general linear models were used to examine sociodemographic and behavioral characteristics associated with sleep duration, chronotype, and social jet lag in adolescents. One hundred and fifteen participants completed Phase I (self-reported sleep measures), and 69 of these participants completed Phase II (actigraphy-estimated sleep measures). Black adolescents had shorter free night sleep than Hispanics. Youth with later chronotypes ate fewer fruits and vegetables, drank more soda, were less physically active, and took more daytime naps. Based on these findings, recommendations for individual support and school policies are provided.

Predictors of poor sleep quality among Lebanese university students: association between evening typology, lifestyle behaviors, and sleep habits

Adequate, good night sleep is fundamental to well-being and is known to be influenced by myriad biological and environmental factors. Given the unavailability of sleep data about Lebanon, the cultural shifts and socioeconomic pressures that have affected many aspects of society, particularly for students and working adults, as well as our understanding of sleep in university students in other countries, we conducted a national study to assess sleep quality and factors contributing to sleep and general health in a culture-specific context. A self-filled questionnaire, inquiring about sociodemographics, health-risk behaviors, personal health, and evaluating sleep quality and chronotype using standard scales was completed by 540 students at private and public universities in Lebanon. Overall, they reported sleeping 7.95±1.34 hours per night, although 12.3% reported sleeping <6.5 hours and more than half scored in the poor-sleeper category on the Pittsburgh Sleep Quality Index (PSQI). Sleep timing differed markedly between weekdays and weekends, with bedtimes and wake-up times delayed by 1.51 and 2.43 hours, respectively, on weekends. While most scored in the "neither type" category on the Morningness-Eveningness Questionnaire (MEQ), 24.5% were evening types and 7.3% were morning types. MEQ score was significantly correlated with smoking behavior and daily study onset, as well as with PSQI score, with eveningness associated with greater number of cigarettes, later study times, and poor sleep. We conclude that the prevalence of poor sleep quality among Lebanese university students is associated with reduced sleep duration and shifts in sleep timing between weekdays and weekends, especially among evening types. While chronotype and certain behavioral choices interact to affect sleep dimensions and quality, raising awareness about the importance of obtaining adequate nighttime sleep on daily performance and avoiding risky behaviors may help Lebanese students make better choices in school and work schedules.