Associations between sleep characteristics, chronotype and body mass index among Chinese college freshmen

Associations of body composition with physical activity, nutritional intake status, and chronotype among female university students in Japan

BACKGROUND

Having higher muscle mass in early adulthood is an important factor in preventing sarcopenia. However, university students undergo lifestyle changes compared to their high school years, which may lead to changes in body composition, such as an increase in body fat and a decrease in muscle mass. The study aimed to investigate the association between body composition and lifestyle behaviors, including chronotype, among Japanese female university students, due to the prevalence of underweight among young females in the country.

METHODS

The physical activity level (PAL), daily dietary intake status, morningness-eveningness questionnaire (MEQ) score, and body composition of 230 students were assessed in this cross-sectional study. Body composition was measured using a multifrequency bioelectrical impedance analyzer, and body mass index (BMI), body fat percentage (%BF), and skeletal muscle mass index (SMI) were determined.

RESULTS

Individuals who were evening type (ET) had a higher %BF and lower SMI than those who were non-ET, but no differences in body weight or BMI were found. Although ET individuals had lower total energy intake, protein intake, and PALs than non-ETs, the differences were small. However, multiple regression analyses showed that SMI was significantly positively associated with MEQ and PAL, and %BF was significantly negatively associated with MEQ and PAL.

CONCLUSION

These results suggest that female university students with lateness of chronotype and low physical activity have a body composition imbalance resulting in higher body fat and lower muscle mass. Therefore, young females may need to take chronotype-specific measures (especially ET individuals) to help them maintain an appropriate body composition.

Factors associated with sleep disorders among university students in Jiangsu Province: a cross-sectional study

Objective

This study aims to establish the precise prevalence of sleep disorders among university students in Jiangsu Province. Utilizing a representative sample of students, we measured their sleep quality based on the Pittsburgh Sleep Quality Index (PSQI). Our objective is to quantitatively assess the magnitude of sleep quality and identify key factors. By detailed analysis of these relationships, our study seeks to provide actionable insights for the development of targeted interventions to enhance sleep quality within this population.

Methods

From October to November 2022, we conducted a cross-sectional web-based survey in Jiangsu Province, China. Using convenient cluster sampling in each college, a total of 8457 participants were selected. The PSQI was applied to assess sleep quality among university students. Data collected included sociodemographic details, scores from the Mobile Phone Dependence Index (MPAI) and psychological resilience measured by the Connor-Davidson Resilience Scale (CD-RISC).

Results

The overall prevalence of poor sleep quality among the participants was 39.30%. Binary logistic regression analysis revealed that higher physical activity (OR = 0.921; 95% CI: 0.779-1.090), earlier roommate bedtimes (OR = 0.799; 95% CI: 0.718-0.888), quieter dormitories (OR = 0.732; 95% CI: 0.647-0.828) and higher psychological resilience (OR = 0.982; 95% CI, 0.979-0.984) were protective factors linked to lower risk of poor sleep quality. Conversely, being a female student (OR = 1.238; 95% CI: 1.109-1.382), being a senior (OR = 1.582; 95% CI: 1.344-1.863), single-child status (OR = 1.195; 95% CI: 1.077-1.326), regular smoking (OR = 1.833; 95% CI: 1.181-2.847), regular alcohol consumption (OR = 1.737; 95% CI: 1.065-2.833), high academic stress (OR = 1.326; 95% CI: 1.012-1.736), high employment stress (OR = 1.352; 95% CI: 1.156-1.582), dissatisfaction with dormitory hygiene (OR = 1.140; 95% CI: 1.028-1.265), poor self-rated physical health (OR = 1.969; 95% CI: 1.533-2.529), poor self-rated mental health (OR = 2.924; 95% CI: 2.309-3.702) and higher mobile phone dependency were risk factors associated with an increased likelihood of poor sleep quality.

Conclusion

The sleep quality among university students should attract immediate attention. The development of public services and mental health education initiatives is crucial in enhancing the sleep health of this population.

Refractive Associations With Whole Eye Movement Distance and Time Among Chinese University Students: A Corvis ST Study

Purpose

Eye movement has been frequently studied in clinical conditions, but the association with myopia has been less explored, especially in population-based samples. The purpose of this study was to assess the associations of eye movement measured by the Corvis ST with refractive status in healthy university students.

Methods

A total of 1640 healthy students were included in the study (19.0 ± 0.9 years). Eye movement parameters (whole eye movement [WEM]; whole eye movement time [WEMT]) were measured by the Corvis ST. Spherical equivalent (SE) was measured using an autorefractor without cycloplegia. IOL Master was used to assess axial length (AL).

Results

AL was negatively correlated with WEM and WEMT (rWEM = -0.28, rWEMT = -0.08), and SE was positively correlated with WEM and WEMT (rWEM = 0.21, rWEMT = 0.14). For the risk of high myopia, breakpoint analysis and restricted cubic spline model showed that the knots of the significant steep downward trend of WEM and WEMT were 0.27 mm and 20.4 ms, respectively. The piecewise linear regression model revealed a significant correlation between AL, SE, and WEM when the value of WEM was below 0.27 mm. Additionally, when WEMT exceeded 20.4 ms, a significant decrease in AL and an increase in SE were observed with increasing WEMT.

Conclusions

A larger distance and longer duration of eye movement were correlated with a lower degree of myopia and shorter AL, and there was a threshold effect.

Translational Relevance

The findings might aid in understanding the pathogenesis of myopia and provide a theoretical foundation for clinical diagnosis and prediction.

Chronotypes and their association with sleep quality among Chinese college students of Anhui Province: a cross-sectional study

OBJECTIVES

To describe the prevalence of chronotype and sleep quality among Chinese college students and explore the relationship between chronotype and sleep quality.

DESIGN

A cross-sectional study.

SETTING

Four colleges and universities in Anhui, China, between November and December 2020.

PARTICIPANTS

A total of 4768 college students were recruited using a stratified, multistage, cluster sampling survey.

OUTCOME MEASURES

Morningness-Eveningness Questionnaire 19 was used to determine the chronotype of the students and the Pittsburgh Sleep Quality Index (PSQI) was used to measure their sleep quality. The multiple logistic regression model was used to explore the potential association between chronotype and sleep quality.

RESULTS

The self-reported proportions of evening-type (E-type), neutral-type and morning-type among college students were 51.17%, 45.14% and 3.69%, respectively. The mean PSQI score was 4.97±2.82 and the prevalence of poor sleep quality was 18.2%. After adjusting the covariates by multiple logistic regression analysis, E-type was positively associated with subjective sleep quality (OR=1.671, 95% CI 1.414 to 1.975), sleep latency (OR=1.436, 95% CI 1.252 to 1.647), sleep duration (OR=2.149, 95% CI 1.506 to 3.067), habitual sleep efficiency (OR=1.702, 95% CI 1.329 to 2.180), daytime dysfunction (OR=1.602, 95% CI 1.412 to 1.818) and overall poor sleep quality (OR=1.866, 95% CI 1.586 to 2.196).

CONCLUSIONS

College students mainly exhibited E-type, and an elevated prevalence of poor sleep quality existed among these students. The E-type was positively associated with poor sleep quality.