The COVID-19 Pandemic’s Consequences on Medical Students’ Sleep Patterns and Technology Addiction

Abstract

Introduction: Sleep disorders are an important public health problem. In the case of young people, and especially students, due to both academic demands and social life, many situations can lead to sleep disturbances. Aim: To evaluate the quality of sleep in medical students and its relationships with technology addiction. Background: Current research indicates that the technology usage by the university students determined an impaired sleep quality and a shortened sleep duration. Method: One hundred eleven second-year students attending medical education were included in the study. Its dependent variable was low sleep quality and independent variables were behavioral factors, smartphone addiction, computer usage, watching TV and other questioned features. A sleep questionnaire to assess the sleep quality in medical students was provided to medical students. This study was conducted in the University of Medicine and Pharmacy of Iasi, Romania. Results: The majority of medical students had shorter, irregular sleep duration and consumed energizing and stimulating drinks. Conclusions: In COVID-19 pandemic, the students’ tech addiction associated with the behavioral factors was found as risk factors for poor sleep quality.

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Cojocaru, T. , Pinzariu, G. , Hurjui, A. , Hurjui, R. and Barbu, R. (2022) The COVID-19 Pandemic’s Consequences on Medical Students’ Sleep Patterns and Technology Addiction. Journal of Biosciences and Medicines, 10, 214-225. doi: 10.4236/jbm.2022.1011017.

1. Introduction

Sleep disorders are frequent in the general population [1]. The medical students appear to be more vulnerable to sleep problems. Students in the University of Medicine show significantly lower sleep quality compared to students in the Faculty of Law or Economics [2]. Causes would be the multiple academic responsibilities, increased time spent studying, having to do guard duties in hospitals, higher exam nerves, making them more stressed and less satisfied with their results. In medical school, the length of study years is long and thus it becomes important to know the quality of sleep that can affect the neurocognitive performance and quality of life. Before becoming doctors, medical students must complete a long and demanding academic program. Therefore, it is critical to determine whether they have sleep issues, how severe they are, and whether they have any impact on their academic performance or general well-being. The long duration and high intensity of studying, clinical responsibilities that include overnight on-call duties, work that can be emotionally negatively affecting, and lifestyle choices could all be contributing factors to medical students’ sleep issues. Thus, stress is a trigger for insomnia and poor sleep quality.

Due to the technological advancements, particularly in the medical field, new technology seems to be the vital force that keeps people going with their daily lives. It has gotten simpler, quicker, comfortable, and more active. Although technology has improved our lives and expanded our thoughts, individuals often get overly dependent on it in search of its comfortable pleasures to the point that they find it impossible to envisage life without it. The students’ routines have become fragile and susceptible due to their meaningless preoccupation with abusing technology. Unprecedented physical, medical and other benefits were undoubtedly provided by their improvements, but the human race’s existence would suffer because of this overuse. Similar to Internet’s, smartphone addiction can lead to behavioral and mental health issues when used excessively.

The modernization of society is accompanied by the emergence of technologies that can lead to increased student interest and distraction from learning.

Students’ sleep quality during the pandemic may have significantly decreased due to the increase of researching for educational purposes, which is directly linked to late-night electronic device usage [3].

Since the end of the 20th century, the emergence of various portable electronic devices and lighting systems based on light emitting diodes (LED) affected people’s daily lives. LED lamps emit light primarily at visible wavelengths, which includes a significant amount of blue light. By affecting the photoreceptor cells in the retina, blue light exposure plays a crucial part in the control of the circadian rhythms of sleep-wake [4]. Blue light inhibits the production of melatonin in the pineal gland and some studies have found that prolonged exposure to blue light, primarily from mobile phones, has a severe impact on the balance of circadian cycles and the quality of sleep [5]. When the wavelength is <300 nm, different tissue features of the human eye’s refractive medium have various effects on how light penetrates these layers. The iris or the pupil can absorb light with a wavelength of between 300 and 400 nm after it passes through the cornea. The most dangerous wave blue light is between 415 and 455 nm. Direct crystal penetration into the retina results in irreversible photochemical retinal damage. Blue light has a short wavelength, which causes the focus to be in the front of the retina rather than the center, making it worsen nearsightedness and fatigue from prolonged exposure to blue light. In addition to harming the retina through the eye’s refractive medium, excessive blue light (especially at night, when melatonin production is at its peak) inhibits melatonin secretion in the pineal gland, increases corticosteroid production, and adversely affects sleep quality. Dry eyes can result from this increase in cortisol production, because it decreases parasympathetic nerve excitability and tear secretion [6]. Melatonin induces sleepiness by operating as the hormonal trigger for the body’s temperature loss at night and the induction of sleep [7].

This study aimed to investigate the quality of sleep in medical students and to investigate its relationship with technology addiction.

The COVID-19 pandemic has been affecting educational systems around the world for the past two years, notably affecting the most vulnerable students. The pandemic has exacerbated disparities and rendered the already serious educational crisis worsened. Although the schools were opened in the vast majority of countries during the Omicron variant period because of the implementation of health protocols and immunization programs, the effects on learning, health, well-being, and dropout rates were severe [8] [9]. According to data released by UNICEF on March 3, 2021, more than 168 million children’s schools around the world have been entirely closed for almost an entire year as a result of COVID-19 lockdowns [8].

Concerns about the COVID-19 pandemic have a significant impact on students’ daily routines, including their sleep patterns and technology addiction. Staying at home for a long time may also result in their eating patterns and physical activity [10]. The anxiety and stress produced by the lockdown may result in a change in sleeping pattern, disrupted sleep because of overstimulation, and/or nightmares [11].

Modern technology has been used by medical schools to successfully improve medical education in both developed and developing nations. Medical students’ education has undergone considerable adjustments because of the COVID-19 pandemia (e.g., virtual education and online classes) [12].

To maintain social distance, reduce in-person contact, and slow the pandemic’s spread, educational activities—particularly in countries that enforced total lockdown shifted from physical presence to virtual learning via digital communication platforms. It is common for medical students to read and browse the Internet all day and night looking for academic content that might be relevant to their course of study. When they are unable to regulate their Internet use, this may predispose them to acquiring an Internet addiction [13].

Thus, there is an increasing reliance on social media and online entertainment platforms for social contact because of the decline in face-to-face social interactions and the rise in time spent indoors during the COVID-19 pandemic [14].

Students have developed the habit of using their smartphones before bedtime in response to their increasing popularity [15]. Although data suggests that, the students spent more time on digital devices before bed and had irregular sleep patterns, which may cause poor sleep quality, studies on the specific effects of lockdown on sleep disorders are insufficient [16].

During the Covid-19 pandemic in Indonesia, a study investigated the link between sleep duration, anxiety, and internet usage duration. Their findings revealed a significant link between internet usage and anxiety as well as between sleep duration and anxiety [17].

The present study evaluated the quality of sleep in medical students and its relationships with technology addiction.

2. Material and Methods

One hundred eleven questionnaires were collected and validated from students in the second year at the University of Medicine and Pharmacy “Grigore T. Popa” Iasi. Students were randomly selected and voluntarily consented to participate in the study. The research was conducted during the period October 2021 - March 2022. The questionnaires were distributed on paper by the authors of the research. The questionnaires were anonymous and all conditions of safety and freedom were ensured in their completion. Subject’s data privacy and security have been ensured.

Subjects suffering from chronic diseases were not eligible for analysis. Students completed informed consent and anonymously filled some demographic data (gender, age, race) required to conduct the study for seven consecutive days. From the information collected, the identity of the respondent cannot be identified. The study consisted of daily completion of personal information from the previous and current day: smoking or non-smoking status, bedtime, wake-up time, sleep quality score, number of microawakenings, use of modern technology (mobile phone, laptop, computer, TV or other electronic devices) and consumption of alcohol or energizing drinks.

Statistical analysis was performed using MedCalc version 14.8.1. Software. The descriptive characteristics of the groups’ variables were expressed as mean values and standard deviations (SD). Student t-test and analysis of variance tests were used in the analysis to assess differences between independent groups. Pearson correlation coefficient was applied to estimate the association between sleep quality and the different variables. Prior to using parametric analysis, the data were checked for normality. P-values less than 0.05 were considered significant.

3. Results

One hundred eleven subjects were included in the study, aged between 18 and 28 years, of which 27 (24.3%) were male. The average age was 20.2 ± 1.7 years old. The demographic characteristics of the study group are shown in Table 1.

Table 1. The demographic characteristics of the study group (n = 111).

From the analysis of the data obtained it can be seen that the average duration of night sleep was 7.1 ± 0.9 hours but 36 (32.4%) of subjects supplement night sleep with napping in the afternoon. It is observed that 40.5% of the students declare less 7 hours for night sleep. A longer sleep duration was recorded among female students (7.2 hours), with 31% stating that they sleep at noon.

It was found that 67 students (60.4%) reported that their sleep was irregular, with significant variation in bedtime and wake-up time. In the context of irregular sleep, we found that 63 (56.8%) of the respondents used energizers and stimulants. Using a scale from 1 to 5 to rate sleep quality, where 1 represents poor quality sleep and 5 represents good quality, restful sleep, we obtained a mean of 3.9 ± 0.6, with a median of 4 (Table 2).

Students who declared sleepless nights, they have used electronic devices in an average of 2.1 hours/day, a significantly longer period than those who declared otherwise (1.4 hour/day; p = 0.001). Other factor that can contribute to sleepless nights was the increased level of energy drinks consumption in the subjects with sleepless compared to regular sleepers (0.5 units/day versus 0.2 units/day, p = 0.058).

Of the subjects who had sleepless nights, 47.8% stated that they had afternoon naps, as a method of recovering from nighttime sleep deprivation. Compared to students who did not have sleepless nights, 21.5% reported sleeping at lunchtime (p = 0.007).

Table 2. Sleep features and smartphone use (n =111).

4. Discussions

This study examined the sleep pattern and the prevalence of technology addiction among a range of medical students at a university in Romania. The most of the participants in this research (55%) could be classified as having technology addiction (mild to moderate; 1 - 3 hours per day).

An increase in mean sleep time (6.7  ±  0.9 hours/night before lockdown and 7.4  ±  1.1 hours/night during lockdown was reported in an Italian study of 6-year medical students (714 before and 394 during lockdown) [18]. This is consistent with other studies [16] [19]. That mean sleep time increased during lockdown. Maintaining flexible and less-busy schedules for students may help to keep this improvement after the pandemic time.

Due to physical isolation requirements and worldwide lockdowns, including medical schools, the COVID-19 pandemic has inevitably resulted in an increase in the usage of digital technologies [20].

A study revealed that during the COVID-19 pandemic, 3793 students had higher odds of reporting changes in sleep pattern and increases in screen use comparing with 13,215 non-students [21]. The term “screen use” refers to the activities performed on devices with screens and the time spent using them (game consoles, laptops and televisions).

Poor sleep quality is prevalent among medical university students worldwide, according to some research that is consistent with our findings. This frequency was 44.23% in Nepal [22], 39.5% in Brasil [22], 62% in Ethiopia [23], 75.8% in Slovenia [24], 31.9% in China [25].

A third of students sleep less than the required 7 - 8 hours per night for a young adult, and the majority of medical students have poor sleep quality [26].

A study published by Saguemet al. that assessed predictors of sleep quality in medical students during COVID-19 revealed poor sleep quality and a 15.5% proportion of students reporting a sleep duration of 7 hours or less [27]. This study found that sleep disorders in medical students included in the analysis were associated with nightmares, waking up during the night or too early in the morning, nocturia, pain, breathing disorders, snoring, and sleep disturbances.

In previous research published by Micu et al., a positive, statistically significant correlation was observed between the consumption of mental stimulants and sleep fragmentation [28].

Similar data were observed in the present study, in which irregular sleep was associated with shorter sleep duration (<7 h), and night awakenings in 40.5% of students.

We note that the average sleep duration of 7 hours reported by the students in this study is at the bottom end of the recommended average sleep duration of 7 - 8 hours reported by Watson et al. [26]. The same authors showed that for a sleep duration of less than 7 hours, the cognitive performance and memory are significantly reduced. In addition, the same young people are at risk of worse health and reduced quality of life.

To improve the quality and reduced duration of night sleep, 32.4% of students surveyed “take daytime naps lasting one hour or more” or consume energizing drinks. A study involving medical students found similar results suggesting that these disorders are more likely a cultural problem of this part of the population [29]. The same study found that students in their final years have poorer sleep quality compared to those in lower grades, which could not be quantified by this study. One explanation could be the increased teaching workload faced by medical students in their final year of study.

Insomnia is another common sleep problem caused either by the inability to fall asleep or to maintain undisturbed sleep throughout the night [30]. Previous studies revealed a 9.5% - 27% prevalence of insomnia among undergraduate students [31].

In the present study, 41.4% of the students reported sleepless nights during the week of completing the questionnaire. This percentage includes both nights lost due to difficulty falling asleep and nights lost due to academic or extracurricular activities. It is known that recovery from a sleepless night requires a minimum of 7 nights of normal sleep, which suggests that a significant number of students suffer from chronic sleep deprivation. According to restorative theory [32], the purpose of sleep is to reorganize and store information, and cortical neurons that are involved in memory and careful learning need to rest in sleep [33].

Another problem that has been associated with disturbed sleep quality is the heavy use of electronic devices [34]. As presented in this study, 11.7% of the respondents report intensive use of mobile phones (more than 3 hours per day), and 9% of them watch television more than 1 hour per day. The influence on sleep quality can be partially explained by exposure to blue-enriched light emitted by electronic equipment, similar to exposure to sunlight in the morning [35]. In addition, this use causes cortical arousal and delays sleep. Other results were reported by a study conducted in Vietnam, which found that the majority of respondents (98.1%) used at least one type of electronic device within two hours before bedtime. Smartphones were the most frequently used devices (92.3%), followed by laptops (27.6%) and tablets (4.4%). The same study reveals that during use before bedtime, 69.4% of students did not adjust the screen light (i.e., turning on night mode). About half (50.1%) reported putting their phones in normal mode and 69.4% of them slept next to their phone, including keeping their phone in bed (62.9%) or under a pillow (6.5%) while sleeping [34]. The results of this study reinforce our observations presented above regarding poor sleep quality and reduced sleep duration due to technology addiction. These findings were also similar to previous research conducted among Asian students in Hong Kong (57.5%) and Taiwan (54.7%) [36] as well as in central Vietnam (49.4%) [34].

Depression is one of the major public health problems. It is already proven that among students the prevalence of depression is high (37.2% - 52.4%), and along with anxiety (prevalence between 46% - 63%) and stress (23.7% - 56%) are major factors of sleep quality disturbance [37] [38].

The influence of stress on sleep quality in students was investigated by a study conducted in Egypt and revealed that the level of stress is considered moderate in 69% of the subjects, 24.5% have a high level of stress, while only 6.5% have a low perception of stress [39].

The influence of stress on sleep quality was perceived to be more significant in female students in the same study, as well as by students in the older years (after the third year).

5. Conclusions

From the data collected, correlated with other studies, we can conclude that there is a serious problem caused by the poor quality of sleep in students. Sleep disorders seem to be complex, caused by irregular sleep, with lost nights but also with attempts to supplement night sleep with afternoon naps. To maintain the sleep-wake rhythm, medical students frequently use energizing drinks, which additionally leads to health risks. Other unhealthy behaviors such as smoking and lack of physical activity, although present in a minority of students, are also present.

Rapid interventions are needed to raise awareness of the impact of sleep deprivation on quality of life and cognitive function, such as introducing sleep hygiene courses and warnings on media channels used by students. These programs should warn of the harmful effects of using electronic devices before bedtime, and the time of use should be a maximum of 30 minutes two hours before the scheduled bedtime. The time-of-use warnings or the blocking of blue light emitted by them can be helpful in reducing the impact on sleep. On the other hand, it is necessary to implement information and warning measures on the consumption of energizing drinks, which are widely used, as shown by this study.

6. Limitations

The present study did not assess the influence of the sleep disorders and electronic devices addiction on learning and memory, which can harm students’ academic. The influence of alcohol on sleep was not included in the evaluation, because the study group included students who do not consume alcohol from cultural or religious reasons.

Acknowledgements

Thanks to all participants that took part in the study and enabled this research to be possible.

Authors Contribution

All authors contributed equally to this manuscript. All authors read and approved the final form of the manuscript.

Conflicts of Interest

The authors declare no conflicts of interest regarding the publication of this paper.

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