Excessive Daytime Sleepiness among First to Fourth Year Undergraduate Students of a Medical College in Nepal: A Descriptive Cross-sectional Study

ABSTRACT Introduction: Excessive Daytime Sleepiness is a significant health problem among medical students worldwide which can impair their cognitive and academic performances. Our study aims to determine the prevalence of Excessive Daytime Sleepiness among the first to fourth year undergraduate students of the Nepalese Army Institute of Health Sciences-College of Medicine. Methods: Following the ethical approval from the Institutional Review Committee with registration no. 317, a descriptive cross-sectional study was conducted among the first to fourth year medical students of the Nepalese Army Institute of Health Sciences-College of Medicine from 4th to 10th August 2020. Two hundred and thirty-two students were selected for the study using the stratified random sampling technique. Epworth Sleepiness Scale was used to obtain data on daytime sleepiness among the study participants. The data were entered into Google spreadsheets and later analyzed. Point estimate at 95% Confidence Interval was calculated along with the frequency and proportion for binary data. Results: The prevalence of Excessive Daytime Sleepiness among the first to fourth year undergraduate students of the Nepalese Army Institute of Health Sciences-College of Medicine is found to be 67 (31.02%) at 95% Confidence Interval (24.85-37.19). It was found to be highly prevalent among the fourth year undergraduate medical students 20 (35.09%) and least prevalent among the first year students 13 (26.00%). Excessive Daytime Sleepiness was found to be slightly higher among females 23 (34.85%) than males 44 (29.33%). Conclusions: Excessive Daytime Sleepinessis highly prevalent among medical students in our study as suggested by various international studies.


INTRODUCTION
International classification of sleep disorders defined Excessive Daytime Sleepiness (EDS) as difficulty in maintaining the alert awake state, usually accompanied by a rapid entrance into sleep when the person is sedentary. 1 Heavy academic loads, excessive internet use at night, coffee intake especially at night, too much exposure to artificial lights, etc. increases the risk of JNMA I VOL 58 I ISSUE 229 I SEPTEMBER 2020 EDS. Similarly, EDS might be associated with various sleep disorders such as sleep deprivation, obstructive sleep apnea, narcolepsy, idiopathic hypersomnia, insomnia, circadian rhythm disorders, etc. [1][2][3][4] Even though EDS is a significant health problem, it hasn't been explored much among the medical university students especially in the Asian countries. [5][6] To our knowledge, no studies on EDS has been conducted among the medical students in Nepal.
In this study, we aimed to determine the prevalence of EDS among the first to fourth year undergraduate students of the Nepalese Army Institute of Health Sciences-College of Medicine.

METHODS
A descriptive cross-sectional study was conducted among the first to fourth year undergraduate medical students of the Nepalese Army Institute of Health Sciences-College of Medicine (NAIHS-COM) from 4 th to 10 th August 2020. The study was conducted after receiving ethical approval from the Institutional Review Committee (IRC), NAIHS on July 2020 with the Reg. No. 317. The sample size for the study was calculated using the following formula: Taking 10% as a non-response rate, the required sample size becomes 213.
Hence, we sent the questionnaire to around 232 students (greater than our required sample size i.e. 213) concerning the fact that some of the students might not give the consent to participate in the study.
Participants were selected using stratified random sampling techniques so that every student from the first to fourth year currently enrolled in NAIHS-COM has an equal probability of being selected in the study. First of all, the list of students from the first to the fourth year was obtained from the administrative section of the institute, and each student was assigned a particular random number. An equal proportion of the students from each year was taken for the study. Similarly, the proportion of males and females from each year was also equal. Then the study participants were selected randomly using the computer method keeping in mind the proportion of students from each year and the proportion of males and females in each year.
We used the standard and validated questionnaire based on the Epworth Sleepiness Scale (ESS), which was developed by Dr. Murray Johns in 1990 and later modified in 1997. The permission to use the questionnaire has been granted to us by the Mapi Research Trust, in France. ESS contained 8 questions for which the study participants are asked to rate on a 4-point scale (0-3) correlating the individual's usual chance of dozing off while engaged in eight different activities mentioned in the questionnaires.The overall score range from 0-24 and Excessive Daytime Sleepiness (EDS) is characterized by the ESS>10. The questions were re-typed in google form after the permission from the respective authority and the form was distributed to the selected study participants online.
Out of 232 students, one refused to give consent and 15 of the students were inaccessible to obtain the data. Hence, we obtained complete data from 216 students whose responses were entered into the Google spreadsheet and later analyzed.
Free Full Text Articles are Available at www.jnma.com.np EDS was found to be highly prevalent among the fourth year undergraduate medical students and it is least prevalent among the first year students of NAIHS-COM. Numerically, EDS corresponds to 20 (35.09%) in the fourth year followed by 18 (33.33%) in the second year followed by 16 (29.09%) in the third year, and 13 (26.00%) in the first year (Table 1). Among the 216 participants, there were 150 males and 66 females. In our study, EDS was found to be slightly higher among females than males which correspond to 23 (34.85%) among females and 44 (29.33%) among males ( Table 2). According to our study, the prevalence of EDS among medical students of NAIHS-COM is found to be 31.02%. This finding shows that EDS is a common problem among medical students as well and needs to be addressed on time. We propose that the higher prevalence is due to the heavy academic loads among the medical students as the majority of the medical students in Nepal start their academic classes early in the morning till evening and they spend the remaining hours in the libraries or their hostel room studying till late hours. to conduct further studies to determine the risk factors associated with such EDS which will ultimately help to manage these conditions properly.
Zailinawati AH, et al. 6 and Bokhari NM, et al. 14 in their studies have shown that the prevalence of EDS increases with an increase in the year of study among medical students. Our study also revealed a similar trend except for the prevalence of EDS in the third year which is comparatively lower than that of the second year. The probable explanation behind the finding in these studies is that the burden of study increases from first to final year along with the addition of clinical hours which ultimately compromises the sleep hours at night and leads to EDS. In the case of our study, the reason for the lesser prevalence of EDS in the third year than the second year could be less burden of study as the curriculum in the third year is flexible whereas students in the second year are under high pressure due to increased study loads.
Our study incorporated an equal proportion of males and females through stratified random sampling. There is a slightly higher prevalence of EDS among females than males in our study which is also supported by the results of other studies by Kaur G, et al., 1  There are certain limitations in our study. As the study is being conducted among the medical students of a single medical college the results can't be generalized to students of other medical colleges of Nepal. Hence, multicenter studies on the EDS can be conducted to improve the generalizability of the findings. Being a descriptive cross-sectional study, our study doesn't determine the causality and risk factors associated with EDS. Further studies are necessary to explore the risk factors associated with EDS among medical students in our setting. There might be certain biases associated with our study such as recall bias as the participants may not be involved in all the activities mentioned in the questionnaire in recent times and subjective bias as the questionnaire is based on the subjective feeling of sleepiness on doing different activities.

CONCLUSIONS
Excessive Daytime Sleepiness is found to be highly prevalent among medical students of a medical college in Nepal. Further studies are needed in this aspect to