In the domestic and international literature, there are few studies have been caried out during the new way of COVID-19 pandemic concerning the insomnia of medical students. To our knowledge, this is the first cross-sectional study conducted to systematically investigate the insomnia status and to explore the related psychological factors among of Chinese medical students who have experienced the new wave of COVID-19 pandemic. Our findings help fill a gap in our understanding of insomnia among medical students during the new wave of the COVID-19 pandemic. The results of this study enrich the research on the incidence of insomnia among medical college students in Anhui in the post-COVID-19 era. Therefore, the findings of this study may contribute to research on insomnia among Chinese medical students and help provide some practical suggestions for reducing the risk of insomnia problems.
Our study shows that the COVID-19 pandemic had a significant impact on the insomnia of Chinese medical college students. In our study, the prevalence of insomnia among medical students during this the new wave of COVID-19 pandemic was found to be 27.8%. The prevalence of insomnia symptoms among China medical college students was significantly higher than in the non-epidemic period (18.5%) (5), lower than the COVID-19 lockdown period (25, 26). State Insomnia was reported by 27.8% of the participants, which may reflect the prevalence of insomnia among Chinese medical students after the COVID-19 pandemic. Feelings of loneliness, vulnerability, and worry caused by the COVID-19 pandemics and social isolation can trigger an increase in anxiety and depressive symptoms in medical students. Anxiety and fear can increase cortisol levels, decreased melatonin synthesis, and decreased sleep quality, with changes in the biological rhythms (27, 28). At the same time, it has been suggested that dysregulation of the hypothalamic-pituitary-adrenal axis may be related to the relationship between sleep deprivation and feelings of loneliness and fear (29, 30). The results of this study have very important clinical and public health implications. The possible cause of insomnia may be related to the rapid spread of COVID-19 and the perceived stress of study and life. The differences in the prevalence of insomnia among medical students in different studies could be partly explained by the different study periods and the use of survey instruments. In addition, different school types, grades, majors, research objects and social environments could also affect the occurrence of insomnia among college students. Combining all the above analysis results, this study has strong reasons to suggest that more attention is needed to medical students' insomnia in the context of the COVID-19 pandemic. Therefore, active coping strategies should be developed to prevent insomnia in medical students.
As expected, older age was positively associated with insomnia, reaffirming that age is an important risk factor for insomnia (31). And, the results of this study showed that medical colleges students in higher grades had a higher prevalence of insomnia compared with those in the lower grades, which confirms previous findings. Because final-year college students in China are transitioning from college to society, they have more mental health problems than their peers. University in China, especially in the final year, is an important turning point, and various pressures such as graduation and employment are involved (32). Another explanation may be that severely affected by the COVID-19 outbreak, colleges and universities have cancelled classroom teaching, students had to study online in dormitories, and graduates are unable to find jobs in time, which all contribute to the occurrence of insomnia. Additionally, the results remind the medical school staff and the administrative people to raise awareness among seniors medical college students of good sleep hygiene.
In the early phase of the COVID-19 pandemic, UNESCO stated that 1.5 billion students in 188 countries around the world will face a huge fear of being out of school due to the home isolation policies resulting from long-term lockdowns (33). Online learning was considered to be the main way students learn during the pandemic. With the increasing impact of the COVID-19 pandemic, online learning has become the norm. Study found that online (distance) learning had a direct and long-term impact on college students' physiology, psychology, and lives (34, 35). Study found that the effectiveness of online learning was varied, also the effectiveness could be influenced by students' own characteristics, such as gender, attitude (36), satisfaction (37), learning style (38) and participation (39). Prolonged exposure to digital devices can increase other stressors associated with isolation times and lockdown, ultimately leading to exhaustion and burnout (40). A study showed that online learning increased the psychological stress of Chinese college students (41). The proliferation of online learning led students to spend more time facing screens and smart phones. Long duration of online learning can lead to physical problems for college students, such as eye strain, cervical stiff, dizziness, headache, insomnia, etc. Study found that increased computer usage among teenagers was associated with increased levels of anxiety (42), and increased online activity was associated with moderate-to-severe depression (43). Medical students with greater adaptability showed more active learning enthusiasm and greater learning engagement in online learning (44) The high satisfaction with online learning can stimulate students' sense of achievement and adaptability in the online learning process, improve learning efficiency, and effectively alleviate their psychological pressure and reduce insomnia. As a result, teachers can take flexible measures to stimulate students' interest and enthusiasm for online learning, create an atmosphere of positive communication, and increase students' participation in online learning.
Another key finding is that during the new wave of COVID-19 pandemic, Fear of COVID-19 among medical college students was positively correlated with insomnia. Overall, our findings were consistent with our research hypothesis. The highly contagious nature of COVID-19 and the fact that it has serious consequences may lead to fear COVID‐19 among medical students (45). Previous research reported indicate that the COVID-19 pandemic and dramatic changes in learning styles pose significant threats to medical students' physical and mental health, such as fear of the COVID-19 pandemic. The further development of COVID-19 fear may lead to the occurrence of stress, depression, anxiety psychological disorders and endocrine disorders, growing fears of COVID-19 can trigger a range of serious physical dysfunctions, such as insomnia (15). Research had shown that fears of COVID-19, including fear of the future and fear of contracting the COVID-19, as well as concerns about their own health, which is linked to poor mental health problems (46). In accordance with the Chinese government epidemic prevention policy on COVID-19, strict regulations have been issued for college students in China to prevent the spread of COVID-19 in the university community. The situation has created panic among medical students, especially those living in cities with the COVID-19 pandemic. This finding suggests that reducing COVID-19 fear among medical students may be a good strategy for reducing stress and improving their insomnia among medical students during the new COVID-19 pandemic. Therefore, reducing the fear of COVID-19 could help medical students to perceive less stress. It can be considered an unavoidable result that fear of COVID‐19 leads to insomnia problems among medical students. Therefore, college administrators should not ignore the fears of COVID-19 among medical students during the COVID‐19 pandemic. The exact mechanism between fear of COVID‐19 and insomnia deserves further study.
We also found that anxiety-depression comorbidity was significant positive associated with insomnia among Chinese medical college students, the results of this study was similar to those of previous studies (47). After binary logistic regression analysis, we found that anxiety-depression comorbidity may be a potential risk factor for insomnia in medical students. Hussein et al. (48) reported that more than 50% of students in Bangladesh were suffering both severe depression and generalized anxiety as a result of the COVID-19 outbreak. The bi-directional relationship between insomnia and depression has been widely recognized by domestic and foreign scholars. Previous study (49) has shown that the HPA axis is thought to be the physiological link between mental health and insomnia problems. Therefore, medical college students with anxiety-depression comorbidity often experience insomnia problems due to circadian rhythms and the HPA axis. A study by Zhao Y et al. (50)a structural equation modeling found that uncertainty about the COVID-19 pandemic is closely related to anxiety, depression sensitivity, and in turn affects insomnia through depression and anxiety. It cannot be ignored that due to the cross-sectional design of this study, this study did not demonstrate the causal relationship between insomnia and depression and anxiety co-morbidities. The possible reasons for the correlation between insomnia and depression and anxiety co-morbidities may include the psychological impact of the COVID-19 pandemic on medical students, and factors of COVID-19 epidemic stress.
We also found that loneliness was independently associated with insomnia in medical college students, which was consistent with findings prior to the COVID-19 pandemic. Prior research demonstrating that the relationship between loneliness and insomnia is bidirectional (34), therefore loneliness provides an important foundation for clinical insomnia among medical college students during the COVID-19 pandemic. In the context of the COVID-19 pandemic, this study indicates that greater loneliness is positively associated with greater insomnia among medical college students. With the current rollout of strict social distancing measures to control the COVID-19 pandemic, loneliness had become a prominent public health problem, especially among medical college students. The management of strict COVID-19 quarantine measures never experienced before has led to the gradual distancing of medical college students, resulting in social isolation. Lack of interpersonal communication can also cause or exacerbate loneliness.