Introduction

Excessive daytime sleepiness (EDS) refers to uncontrollable sleepiness during the day, which is temporary sleepiness or sleep that is difficult to maintain or cannot be contained while staying awake and can occur at any time and in any setting1,2. Studies have reported that the incidence of EDS in the general population is about 12–16%2, while the incidence of EDS in college students is about 24–39%3,4, and the incidence of EDS in medical students is 24–54%1,2,3,4,5. EDS can lead to inattention, decreased academic performance, negative emotions (anxiety, depression), and reduced life satisfaction 6,7,8,9. In addition, some studies have found that the occurrence of EDS has a particular relationship with drug abuse, criminal behaviour, and self-injury suicide9,10,11. Nurses are an indispensable force in medical and health care, playing a key role in protecting lives, preventing diseases, treating diseases and promoting health. Nursing students are the future nursing professionals, and the professional level of nursing students directly affects the patient’s medical experience and treatment effect.

Some studies have found that nursing students’ lifestyle factors, behaviors, daily commitments and sleep habits can lead to daytime sleepiness, seriously affecting their academic and professional performance12. The occurrence of daytime sleepiness will affect the cognitive function of nursing students and affect the nursing work of patients13,14,15. Therefore, it is essential to identify the factors that influence EDS in nursing students as early as possible and reduce its occurrence. This study aimed to (1) determine the prevalence of EDS among nursing students, (2) examine the association between internet addiction and EDS, and (3) explore coping strategies for affected students.

Methods

Design

A multicenter cross-sectional study was conducted among nursing students from eight universities across Shandong, Jiangxi, Shanghai, Guangdong and Liaoning provinces between August and September 2024. The electronic questionnaire was distributed through nursing teachers. The first page of the questionnaire contained a detailed informed consent statement explaining the study purpose, procedures, confidentiality measures, and participants’ rights. Explicit consent was obtained digitally before participants could access the survey questions; those who declined consent were automatically directed to a termination page. The study was approved by the hospital’s research ethics committee [Peking University Shenzhen Hospital Ethics Committee Approval No. 2022–094], and all procedures adhered to the principles of the Declaration of Helsinki. From the initial 1710 responses collected, 52 were excluded due to incomplete responses or inconsistent answer patterns, resulting in 1658 valid responses.

Measures

General information questionnaire

Gender, Age, Educational level, Clinical practice, Family situation, Monthly household income, Father’s educational level, Mother’s educational level, Recent hospitalization etc.

Internet addiction

The Internet Addiction Scale was compiled by Yeong (1999) of the University of Pittsburgh16. It has been widely used to measure Internet addiction17. The scale consists of 20 items, each with five choices (almost none–always), assigned a score of 1–5. It includes four dimensions: network damage, compulsive symptoms, network relationship addiction, and the influence of destructive emotions. The subjects’ Internet use was determined according to the scale’s total score. The higher the score, the more serious the degree of addiction to the internet. The score of 20–49 was everyday Internet use, and the score of 50–100 was internet addiction. Previous studies have shown that this scale has good reliability and validity in college students18,19. In this study, the Cronbach’s α for the sample was 0.949.

Epworth sleepiness scale (ESS)

The Epworth Sleepiness Scale translated and revised by Peng Lili et al. was adopted to evaluate the daytime sleepiness of college students20. The scale consisted of 8 items and was scored with 4 points, 0 indicating “never dozing off” and 3 indicating “often dozing off”. The total score ranged from 0 to 24 points. The higher the score, the more serious the degree of daytime sleepiness. A total score of ≥ 11 indicates excessive daytime sleepiness. Previous studies have shown that this scale has good reliability and validity in college students15. In this study, the Cronbach’s α coefficient of this scale was 0.877.

Statistical analysis

Data analysis was conducted using SPSS 26.0 statistical software. Counting data were presented as the number of cases and percentage, and inter-group comparisons were performed using the Chi-square test. Measurement data were expressed as Mean ± standard deviation or [M(Q1, Q3)], and inter-group comparisons were carried out using the t-test or non-parametric test of two independent samples. A binary logistics regression model was employed to assess the impact of different factors on EDS, with variable screening conducted using a stepwise backward method. A significance level of P ≤ 0.05 was considered statistically significant.

Results

General information of nursing students

This study investigated 1658 nursing students, including 367 male and 1291 female students. 299 (18.03%) nursing students had EDS, and 1359 (81.97%) did not. There were statistically significant differences between non-Excessive Daytime Sleepiness and Excessive Daytime Sleepiness nursing students in terms of Educational level, Clinical practice, Drinking, Psychosomatic illness, and Internet addiction (P < 0.05), as shown in Table 1.

Table 1 Information on demographic characteristics.
Full size table

Multifactor analysis of EDS in nursing students

In univariate analysis, statistically significant indicators such as Education level, Drinking, and Physical and mental illness, and Internet addiction were taken as independent variables. EDS of nursing students was taken as the dependent variable and binary Logistic regression analysis was conducted. The results showed that Clinical practice, Internet addiction, Drinking, and Physical and mental illness were the influencing factors for sleepiness between nursing days (P < 0.05), as shown in Table 2.

Table 2 EDS Logistic regression analysis of nursing students.
Full size table

Discussion

Incidence of ESD

The results of this study found that the incidence of EDS among nursing students was 18.03% (299/1658), which was similar to the results of Demirde’s survey on nursing students (17.9%)21. It is higher than the EDS survey results of Chinese scholar Wang Zhan on college students in a university in Jiangsu (15.7%)22. Nursing is a major that has strong theory and practice. Compared with college students in other majors, nursing students need to take examinations of clinical practice, skill operation and theoretical knowledge, which leads to a heavier learning burden and decreased sleep quality, leading to EDS. Lack of sleep will reduce learning efficiency, cognitive impairment, and adverse effects on individuals’ physical and mental health23,24. Therefore, early identification of EDS and timely support and help to nursing students are of great significance in preventing EDS and reducing adverse events caused by EDS.

Internet addiction and drinking

Internet addiction is an influential factor of EDS in nursing students. Research shows that Internet addiction is a positive correlation factor for insomnia, and the higher the degree of Internet addiction, the higher the risk of insomnia25. Foreign studies have shown that among adolescents with Internet addiction, 26.7–69.4% of them have sleep disorders of varying degrees26,27. About 75% of students have experienced dizziness, fatigue, neurasthenia, depression, anxiety and other symptoms caused by Internet addiction, leading to the occurrence of EDS28. Therefore, for nursing students with Internet addiction, it is essential to guide them to rebuild a healthy lifestyle and sleep habits, including limiting Internet use time, establishing a regular sleep schedule, avoiding the use of electronic devices before going to bed, and actively coping with the adverse effects of Internet addiction. Alcohol consumption is a risk factor for daytime sleepiness among nursing students, and the results of this study are consistent with those of previous studies1,29,30. Alcohol use disrupts the balance of the central nervous system and endocrine system and affects the quality of sleep31. In addition, alcohol can disrupt the body’s sleep rhythm system, causing the body clock to be confused, making you feel sleepy and sleepy during the day. Therefore, schools and families should pay more attention to nursing students who drink alcohol, provide personalized measures for alcohol abstinence, reduce the number of nursing students who drink alcohol, improve their sleep quality and improve the occurrence of EDS.

Clinical practice and psychosomatic illness

This study showed that clinical practice was a risk factor for EDS in nursing students.

Research has found that due to factors such as long-term and frequent night shifts, highly tense and high-workload working environments, nurses’ sleep disorders are exacerbated32. After shift work, they are unable to quickly return to a normal sleep–wake cycle, which in turn leads to daytime sleepiness. Clinical internship is a crucial stage for the combination of medical theory and practice, and it is also an inevitable process for student nurses to gradually transform into professional nurses33. Nursing interns often need to study clinical knowledge for a long time and at a high intensity. They also have to follow clinical instructors on night shifts and endure the clinical practice pressure such as night shifts and high-intensity working environments. All these factors can bring psychological pressure to nursing interns, which in turn affects their sleep quality34. In addition, nursing students are faced with three shifts in clinical practice. When their circadian rhythm changes are out of sync with the natural circadian rhythm, it will lead to circadian rhythm disturbance, which will have an impact on individual sleep quality and EDS to a certain extent35. Studies have shown that the incidence of depression and anxiety among nursing students is 54.7% and 28.9%36. Anxiety and depression are common physical and mental diseases among nursing students. Among depressed students, the incidence of EDS is as high as 50.4%37. EDS is closely associated with anxiety and depression among nursing students. As a common symptom of both sleep disorders and depressive conditions, EDS contributes to reduced positive affect, motivation, and concentration. It further promotes negative cognitive patterns—such as rumination and pessimism—which are core features of depression38,39. Additionally, EDS can exacerbate nighttime sleep difficulties, including increased insomnia, and heighten the likelihood of daytime napping, thereby further disrupting the sleep–wake cycle. The underlying psychological mechanism linking EDS to depressive symptoms involves reduced physiological arousal, wherein depressive states lower overall alertness levels, resulting in increased daytime sleepiness38,39,40. According to the study of foreign scholar BOZ41, EDS during rehabilitation is more likely to occur, and EDS may be a residual symptom after recovery from depression. Therefore, nursing educators should not ignore nursing students suffering from physical and mental diseases, especially those with depression, increase communication, provide good sleep conditions, pay attention to the sleeping conditions of nursing students, reduce the occurrence of EDS, and guide students to seek help from psychiatric professionals when necessary.

Conclusion

This study investigated the incidence of daytime sleepiness and its influencing factors in 1658 nursing students. The study found that the incidence of EDS was higher among nursing students, and the main influencing factors included Internet addiction, drinking, psychosomatic diseases and clinical practice. These factors affect students’ learning and quality of life and may also negatively affect their future career performance as nursing students. The findings underscore the importance of integrating sleep health and psychological support into nursing education; consequently, we suggest that schools and relevant departments take effective measures—such as providing sleep health education, psychological counselling, and optimized curriculum arrangements—to improve students’ sleep status and overall health.

Strengths and limitations

Although our study conducted an extensive sample survey and provided essential insights into EDS among nursing students, some limitations cannot be ignored. First, the study’s cross-sectional design cannot determine causality, and future studies can use a longitudinal design to explore further the dynamic relationship between various factors and daytime sleepiness. Second, the data mainly rely on self-reports; there may be recall bias and social expectation bias; future research can be combined with objective measurement methods (such as sleep monitoring equipment) to improve the accuracy of the data. In addition, the sample did not cover all regions of China, which may limit the universality of the results. Future studies should expand the sample scope to include more institutions and areas to improve the study’s external validity. Finally, other potential influencing factors (such as eating habits, exercise frequency, caffeine intake and screen time before bed. etc.) were not fully considered in the study, and more variables can be included in future studies to analyze the influencing factors of nursing students’ EDS comprehensively.