Short Sleep Duration Is Associated with Overestimated Myopia in University Students

To investigate the association between objectively monitored sleep patterns and overestimation of myopia among university students.

A cross-sectional study enrolled 144 university students aged 17-23 years. Sleep parameters (total duration, light sleep, deep sleep, bedtime/woke time) were objectively monitored for 7 consecutive days using smart wearable devices. Ocular biometric parameters were measured using an optical biometer. Spherical equivalent refraction (SE) was obtained via auto-refraction both before and after cycloplegia. Based on the difference in SE before and after cycloplegia (DIFF = SE_post-cycloplegia - SE_pre-cycloplegia), participants with DIFF ≥ +0.50 D were defined as the overestimated myopia group. Linear mixed-effects models (LMM) were used to analyze the association between sleep parameters and overestimated myopia, adjusting for confounders including age, sex, parental myopia history, and daily near work activities.

A total of 126 participants completed data analysis. The prevalence of overestimated myopia was 26.19%. Compared to the non-overestimated myopia group, the overestimated myopia group exhibited the following significant characteristics: shorter total sleep duration by approximately 0.6 h (6.82 ± 0.84 h vs 7.43 ± 0.74 h, P < 0.001); shorter light sleep duration by 0.46 h (4.73±0.93 h vs 5.19±1.05 h, P = 0.006); and delayed bedtime by 0.80 h (1:42±1:04 vs 00:53 ± 00:52, P < 0.001). No statistically significant differences were observed between the groups in deep sleep duration or woke time.

Among university students, a sleep pattern characterized by shorter sleep duration and delayed bedtime is significantly associated with overestimation of myopia. This finding suggests that sleep behavior may be a potential factor influencing measurement error in non-cycloplegic refraction. Attention should be paid to the sleep status of examinees in clinical practice to enhance the accuracy of refractive measurements.