Association between sleep duration, sleep quality, bedtime and myopia: A systematic review and meta-analysis

Association between sleep and myopia in children and adolescents: a systematic review and meta-analysis

PURPOSE

There is a scarcity of literature focusing on sleep's impact on myopia in children despite an epidemic rise of myopia among the age group and the importance of early prevention. As such, this systematic review-meta-analysis aims to evaluate the association between various aspects of sleep and myopia in children and adolescents aged 0-19 years.

METHODS

We searched PubMed, EMBASE, and Cochrane Library on 08/12/2022 for studies reporting sleep in relation to myopia among children and adolescents. Myopia was defined as spherical equivalent refraction < -0.5 diopter. The primary outcome was the relationship between sleep duration and myopia prevalence. Secondary outcomes include the effect of sleep quality, bedtime, and waketime on myopia prevalence, incidence, and progression. Odds ratio (OR) was estimated with a 95% confidence interval (95% CI).

RESULTS

Eighteen studies (49,277 participants) were included in the review, and six studies (14,116 participants) were included in the meta-analysis for the primary outcome. There was no significant correlation between sleep and myopia prevalence (OR = 0.905, 95% CI = 0.782 to 1.047). Some studies suggested that better sleep quality (2 of 6 studies), earlier bedtime (3 of 5 studies), and later waketimes (2 of 3 studies) had protective effects on myopia.

CONCLUSION

Sleep duration did not affect myopia prevalence in children, while other aspects of sleep had plausible but inconclusive impacts on myopia development and progression. More research with diverse populations and standardized methods of reporting is needed.

Causal relationships between height, screen time, physical activity, sleep and myopia: univariable and multivariable Mendelian randomization

Background

This study aims to investigate the independent causal relation between height, screen time, physical activity, sleep and myopia.

Methods

Instrumental variables (IVs) for exposures and outcome were obtained from the largest publicly available genome-wide association studies (GWAS) databases. First, we performed a bidirectional univariate MR analysis using primarily the inverse variance weighted method (IVW) with height, screen time, physical activity and sleep as the exposure and myopia as the outcome to investigate the causal relationship between exposures and myopia. Sensitivity analysis was used to demonstrate its robustness. Then the multivariable MR (MVMR) and MR-based mediation approach was further used to estimate the mediating effect of potential confounders (education and time outdoors) on causality.

Results

The results of univariate MR analysis showed that taller height (OR = 1.009, 95% CI = 1.005-1.012, p = 3.71 × 10-7), longer time on computer (OR = 1.048, 95% CI = 1.029-1.047, p = 3.87 × 10-7) and less moderate physical activity (OR = 0.976, 95% CI = 0.96-0.991 p = 2.37 × 10-3) had a total effect on the increased risk of developing myopia. Meanwhile our results did not have sufficient evidence to support the causal relationship between chronotype (p = 0.637), sleep duration (p = 0.952) and myopia. After adjusting for education, only taller height remains an independent risk factor for myopia. After adjusting for education, the causal relationship between height, screen and myopia still had statistical significance. A reverse causal relationship was not found in our study. Most of the sensitivity analyses showed consistent results with those of the IVW method.

Conclusion

Our MR study revealed that genetically predicted taller height, longer time on computer, less moderate physical activity increased the risk of myopia. After full adjustment for confounders, only height remained independently associated with myopia. As a complement to observational studies, the results of our analysis provide strong evidence for the improvement of myopia risk factors and provide a theoretical basis for future measures to prevent and control myopia in adolescents.

Mediation effect of sleep time on the association between outdoor activity and myopia in Chinese children and adolescents: a cross-sectional study

BACKGROUND

This study aimed to assess the association between outdoor activity and myopia among children and adolescents and investigate whether sleep time could mediate this relationship.

METHODS

This cross-sectional study was performed on students aged 4-16 years in China, from August 2021 to January 2022. Outdoor activity was assessed by the Assessment Questionnaire of Exposure to Sunlight Activities for Students (AQESAS). Binary logistic regression combined with the mediation analysis was used to analyze the association of AQESAS with myopia and the mediating effect of sleep time on this relationship.

RESULTS

The prevalence of myopia was 53.51% (N = 1609). Multivariate logistic regression analysis showed that more sleep time (OR = 0.794, 95%CI: 0.707-0.893) and a higher score of AQESAS (OR = 0.989, 95%CI: 0.981-0.996) were significantly associated with a decreased risk of myopia. Mediation analysis revealed that sleep time plays a mediating role in the association between outdoor activity and myopia (ACME = -0.0006, P < 0.001), and the mediation proportion was 19.7%.

CONCLUSION

Outdoor activity affects myopia directly and indirectly through sleep time. The result suggested that children may be able to reduce the risk of myopia by promoting sleep through increased awareness of outdoor activity and exposure to sunlight.

Association of sleep traits with myopia in children and adolescents: A meta-analysis and Mendelian randomization study

PURPOSE

The association between sleep and myopia in children and adolescents has been reported, yet it remains controversial and inconclusive. This study aimed to investigate the influence of different sleep traits on the risk of myopia using meta-analytical and Mendelian randomization (MR) techniques.

METHODS

The literature search was performed in August 31, 2023 based on PubMed, Embase, Web of Science, and Cochrane library. The meta-analysis of observational studies reporting the relationship between sleep and myopia was conducted. MR analyses were carried out to assess the causal impact of genetic pre-disposition for sleep traits on myopia.

RESULTS

The results of the meta-analysis indicated a significant association between the risk of myopia and both short sleep duration [odds ratio (OR) = 1.23, 95% confidence interval (CI) = 1.08-1.42, P = 0.003] and long sleep duration (OR = 0.75, 95% CI = 0.66-0.86, P < 0.001). MR analyses revealed no significant causal associations of genetically determined sleep traits with myopia, including chronotype, sleep duration, short sleep duration and long sleep duration (all P > 0.05).

CONCLUSIONS

No evidence was found to support a causal relationship between sleep traits and myopia. While sleep may not independently predict the risk of myopia, the potential impact of sleep on the occurrence and development of myopia cannot be disregarded.

24-H movement behaviors and visual impairment among Chinese adolescents with and without obesity

BACKGROUND

Previous studies have identified obesity, sleep patterns, screen time, and physical activity as independent risk factors for the visual health of adolescents. However, our understanding of how these factors interact and contribute to visual impairment remains limited. This study aimed to investigate the relationship between adherence to the 24-h movement guidelines (24-HMG) and visual impairment in adolescents with and without obesity.

METHODS

We analyzed data from the 2014-2015 China Education Panel Survey. Participants provided self-reported information on their screen time, sleep duration, and physical activity levels. The data on weight, height, and visual acuity were obtained from school health examination reports. Logistic regression analysis was conducted to assess the association between 24-h movement behaviors and visual impairment, reported as odds ratios (ORs) with a 95 % confidence interval (CI).

RESULTS

After controlling for covariates such as sex and age, it was found that adolescents with obesity who adhered to the sleep guidelines had a lower risk of visual impairment compared with adolescents without obesity who did not adhere to the 24-HMG (OR = 0.84, 95 % CI: 0.75-0.94, P = 0.003). Additionally, adolescents who adhered to both the physical activity and sleep guidelines had an even lower risk of visual impairment (OR = 0.58, 95 % CI: 0.42-0.79, P = 0.001).

CONCLUSIONS

Adhering to the Sleep and physical activity + Sleep recommendations in the 24-HMG could significantly reduce the risk of visual impairment in adolescents without obesity. No significant relationship was observed between adherence to 24-HMG and the risk of visual impairment in adolescents with obesity.