Sleep is a naturally recurring process that is important for human life.1 It is crucial for daily activities, as well as for physical and mental health. It is also vital for proper brain function, being as important as air, water, and food.2 Previous studies in America, investigating the regular sleep time for optimal health, have indicated that children aged 6–12 years sleep 9–12 h, teenagers aged 13–18 years sleep 8–10 h, and adults sleep 7–9 h per 24-h periods.3,4
Sleep deprivation is the condition in which one fails to get enough sleep. It is characterized by the following: failure to get the optimum duration of sleep, sleep interruption, and inability to fall asleep in the bed.3 Its impact on individuals of all age levels is growing across the world. Among University students all over the world, sleep deprivation has been specifically increasing over time due to the multifaceted and complex interplay among genetics, academic load, technology, environmental factors, social factors, along with the presence of comorbidities.4,5 It has become a common problem among university students than in the remainder of the population.2 Among university students around the world, sleep deprivation and poor sleep quality are common and have become significant public health problems. Studies have indicated that sleep deprivation among university students ranges from 24% to 49%,6,7 and poor sleep quality among students ranges from 33.7% to 84%.8,9,10,11,12 In Ethiopia, one study revealed that 55.8% of university students had poor sleep quality. Daytime dysfunction was found only among 6.1%, while habitual sleep efficiency was found among 19.4% of the participants.13
Sleep deprivation has been shown to have a detrimental effect on certain aspects of working memory.2 Sleep deprivation has negative consequences in university students, including a wide range of behavioral changes, as well as cognitive and performance deficits. It also leads to declined mood, health problems, and performance deficiency in students, which in turn leads to increased error.14,15 Specifically, health science students are at increased risk for sleep deprivation because they need to be either awake to do their duty in the hospital or under constant study because of their academic load and examinations.16
Different factors can affect sleep quality. For instance, young adults commonly use psychoactive substances due to the latter's temporary stimulant effect and this leads to the problem of poor sleep.17,18 Caffeine use ultimately leads to decreased amount of nighttime sleep and daytime dysfunction, which usually results in sleep deprivation.19 High prevalence of poor sleep quality due to Internet addiction and depression in undergraduate students has been reported in Nepal12 and Ethiopia.13 Use of alcohol results in serious cognitive impairment and psychomotor and sleep disturbances.20 Poor sleep quality has been also found to be associated with poor academic achievement and health problems, as well as increased health-care costs and absenteeism from work.21 In contrast to the above evidence, sleep deprivation has been associated with good academic performance among Iran university students.22 Studies have found that female students experienced sleep problems more than male students,23,24 but no significant difference has been found between male and female students in Northern Malaysia.25 A study on Egyptian medical students has revealed that there was a significant difference among caffeine users and cigarette smokers.26 Another study on Nigerian university students has shown that there was no significant difference among married and unmarried participants, but a chronic physical illness and alcohol consumption were associated with sleep deprivation.27
In general, though different studies indicated that sleep deprivation has become a common problem of university students in different countries, there are very limited studies regarding the prevalence of sleep deprivation and associated factors among university students in sub-Saharan African countries, particularly in Ethiopia. Therefore, this study was intended to determine the prevalence of and factors affecting sleep quality among health science students.
An institution-based cross-sectional study design was used for this study extending from April 10 to April 24, 2019, in Jimma University. Jimma University is found in the Oromia Region at 352 km southwest of Addis Ababa. Jimma University is one of the oldest public higher education institutes in Ethiopia. The study was conducted in three faculties of the Institute of Health at Jimma University, namely, Faculty of Medical Sciences, Faculty of Public Health, and Faculty of Health Sciences. During the survey, 3274 regular undergraduate students were attending education at the Institute of Health of Jimma University.
All regular undergraduate students of the Institute of Health comprised the source population of the study. The study population consisted of randomly selected students who were present during the data collection period and had at least the result of the final semester before the study. Students who had known psychiatry problems other than depression were excluded. The sample size was computed based on a single-population proportion formula with the following assumptions: proportion of problem 55.8% (taken from a previous study),13 95% confidence interval (CI), and marginal error of 5%. Finite population correction formula was used. For nonrespondents, 10% of the final sample size was considered, and the final sample size was 374. After the study population was stratified into 11 departments, proportional allocation was made to each department and the respective batches. Finally, the simple random-sampling technique was used to select the study subjects, by which students were selected at the gates of their classes while they were leaving the class.
Data were collected using the structured and validated PSQI28 questionnaire and Patient Health Questionnaire (PHQ)-9.29 PSQI has 7 components and 19 items. The PSQI is a 19-item self-reported questionnaire that evaluates sleep over the past month. The sleep component scores were summarized to yield a total score ranging from “0” to “21”. A score of “0” indicates sufficient sleep, and higher scores indicate severe sleep deprivation. Depression was measured using the PHQ-9. This questionnaire has 9 questions, with 4 scales ranges from “not at all (0)” to “nearly every day (3)”. Finally, it was dichotomized as “having depression” and “not having depression”. Sleep efficiency was calculated from the total number of hours of sleep, by dividing it by the total number of hours in bed and multiplied by 100.
Data were collected via a self-administered questionnaire, and participants filled out the questionnaire by themselves. Data collectors obtained informed consent and gave orientation to the participants on how to fill the questionnaire and waited for the respondents to complete their questionnaires. The questionnaires were immediately retrieved from the respondents.
The English version questionnaire was translated into Amharic and Afan Oromo local languages. Then, it was retranslated back to English to ensure its consistency. Training was given for 4 baccalaureate science degree nurses, 4 data collectors, and 1 Master of Science degree supervisor 1 week ahead of the actual data collection time on how to take informed consent for ethical issues and collect data. The questionnaire was pre-tested on 5%17 of the sample size at Wolkite University, and some relevant amendment was done. The internal consistency of the items was checked, and Cronbach's α was 0.74. Every questionnaire was cross-checked daily by the supervisors and the principal investigator.
The data were entered into EpiData (Odense Denmark, EpiData Association, version 4.4.1) and analyzed using Statistical Package for the Social Sciences (SPSS; version 23). Descriptive analysis was done to describe the distribution of variables under study. Bivariate logistic regression analysis was computed to identify the candidate variables for multivariate analysis. Variables with a
The study was conducted after ethical clearance, and an official letter was written to the head of each department by the Institutional Review Board (IRB) of the Institute of Health, Jimma University. The aim of the study was explained to the participants, and informed consent was obtained from each participant. Furthermore, they were given assurance that they are free to withdraw consent and to discontinue participation without any form of prejudice. All completed questionnaires were anonymous, and confidentiality of the collected information was ensured throughout the procedure.
Of the 374 students who planned to participate in the study, 365 participants fully responded to the questionnaire, yielding a response rate of 97.6%. According to this study, 303 (83%) participants were not married and 204 (55.9%) participants were males. Regarding exercise, 151 (41.4%) participants engaged in regular physical activity (Table 1).
Sociodemographic and other characteristics of the students of the Institute of Health of Jimma University in the year 2019 (
Variables | Frequency | % |
---|---|---|
Male | 204 | 55.9 |
Female | 161 | 44.1 |
18–19 | 73 | 20 |
20–23 | 215 | 58.9 |
>23 | 77 | 21.1 |
Single | 303 | 83.0 |
Married | 30 | 8.2 |
Divorced | 11 | 3.0 |
Separated | 21 | 5.8 |
Yes | 77 | 21.1 |
No | 288 | 78.9 |
Yes | 151 | 41.4 |
No | 214 | 58.6 |
On campus | 320 | 87.7 |
Off campus | 45 | 12.3 |
Yes | 65 | 17.8 |
No | 300 | 82.2 |
Yes | 36 | 9.9 |
No | 329 | 90.1 |
1st year | 62 | 17.0 |
2nd year | 72 | 19.7 |
3rd year | 70 | 19.2 |
4th year | 70 | 19.2 |
5th year | 60 | 16.4 |
6th year | 31 | 8.5 |
>3.5 | 100 | 27.4 |
3–3.49 | 105 | 28.8 |
2–2.99 | 160 | 43.8 |
Minimal | 161 | 58.5 |
Mild | 84 | 30.5 |
Moderate | 24 | 8.7 |
Moderate-to-severe | 6 | 1.8 |
Concerning substance use, the study showed that the most common substance utilized was coffee, which was followed by Coca-Cola, and the least common one was smoking cigarette (Figure 1).
Substance use and sleep deprivation among students of Institute of Health, Jimma University, in 2019.
The study findings showed that 222 (60.8%) of respondents experienced sleep deprivation. The average nighttime sleep duration of the study participants was 6.29 h (standard deviation [SD]: ±0.854). Participants fell asleep with an average of 23.01 min (SD ± 16.116) after they got into the bed. The sleep latency was reported to be <15 min among 31.8% of the students, 15–30 min among 56.4%, and 30–60 min among 11.5% of students (Table 2; “0” represents sleep latency of <15 min, “1” represents 15–30 min, “2” represents 30–60 min, and “3” represents >60 min). Regarding sleep efficiency, 56.2% of students reported sleep efficiency of >85%. The study also revealed that 161 (44.1%) participants had mild daytime dysfunction due to their sleepiness.
Sleep deprivation and its components’ scores among students of the Institute of Health, Jimma University, 2019 (
Variables | Number (%) |
---|---|
≥7 | 159 (43.6) |
6–7 | 146 (40.0) |
5–6 | 45 (12.3) |
<5 | 15 (4.1) |
0 | 116 (31.8) |
1 | 206 (56.4) |
2 | 42 (11.5) |
3 | 1 (0.3) |
0 | 197 (54) |
1 | 161 (44.1) |
2 | 6 (1.6) |
3 | 1 (0.3) |
>85 | 205 (56.2) |
75–85 | 87 (23.8) |
65–74 | 35 (9.6) |
<65 | 38 (10.4) |
Very good | 116 (31.8) |
Fairly good | 104 (28.5) |
Fairly bad | 145 (39.7) |
0 | 67 (18.4) |
1 | 279 (76.4) |
2 | 19 (5.2) |
3 | 0 |
Not during the past month | 313 (85.8) |
Less than once a week | 51 (14.0) |
Once or twice a week | 1 (0.3) |
Three or more times a week | 0 |
Good sleep | 143 (39.2) |
Sleep deprivation | 222 (60.8) |
The study findings showed that health problems, cumulative grade point average (CGPA), alcohol consumption, khat chewing, smoking cigarettes, and using electronic devices before bedtime had significant association with sleep deprivation. Accordingly, those students who had health problem/s were almost 2 times more likely to experience sleep deprivation (adjusted odds ratio [AOR] = 1.91 [95% CI = 1.01–3.58;
Factors affecting sleep quality among students of the Institute of Health, Jimma University, 2019 (
Variables | Global score (PSQI) | COR (95% CI) | AOR (95% CI) | P–value | |
---|---|---|---|---|---|
Sleep deprived | Not sleep deprived | ||||
Yes | 45 (72.6) | 17 (27.4) | 0.53 (0.29, 0.97) | 1.91 (1.01, 3.58) | 0.044 |
No | 177 (58.4) | 126 (41.6) | 1.00 | ||
>3.5 | 52 (52) | 48 (48) | 1.00 | ||
3–3.99 | 63 (60) | 42 (40) | 0.72 (0.41, 1.25) | 0.72 (0.40, 1.29) | 0.27 |
2–2.99 | 107 (66.9) | 53 (33.1) | 0.53 (0.32, 0.89 | 0.48 (0.27, 0.83) | 0.009 |
Yes | 92 (67.2) | 45 (32.8) | 0.61 (0.39, 0.95) | 0.42 (0.20, 0.89) | 0.023 |
No | 130 (57) | 98 (43.) | 1.00 | ||
Yes | 64 (73.6) | 23 (26.4) | 0.47 (0.27, 0.80) | 0.31 (0.12, 0.82) | 0.018 |
No | 158 (56.8) | 120 (43.2) | 1.00 | ||
Yes | 33 (67.3) | 16 (32.7) | 0.50 (0.26, 0.94) | 0.30 (0.09, 0.93) | 0.05 |
No | 187 (59.6) | 127 (40.4) | 1.00 | ||
<60 | 166 (62.2) | 101 (37.7) | 1.00 | ||
60–120 | 16 (42.3) | 15 (57.7) | 2.24 (0.99, 5.07) | 5.26 (1.78, 15.52) | 0.003 |
Getting optimal sleep is important for memory consolidation, learning, decision-making, and critical thinking.30 Therefore, studying about sleep deprivation is vital to identify factors affecting sleep quality and maintain these cognitive functions at optimal level for performance and mental health.
In this study, 60.8% of students were sleep deprived; 44.6% of the participants reported that they slept >7 h/day, whereas 40% slept only 6–7 h/day. In this study, sleep latency was reported by more than three fifths of the study participants. A study conducted in Egypt showed slightly better results than the current findings: according to the Egyptian study, 51.7% of students slept >7 h/d and 28.1% slept 6–7 h/d.12 The prevalence of sleep deprivation in this study was higher than that in the majority of other studies: United Kingdom,6 Taiwan, China,7 India,8 Malaysia,9 Lebanon,10 Nepal,12 Nigeria,27 Egypt,26 and Ethiopia, but, consistent with the findings of a study in Iran.31 On the other hand, the current study's finding was lower than that from a Saudi university.11 This implies that sleep deprivation is more common among Jimma University students of health sciences, and that students have been affected by inadequate sleep, which has an impact on their cognitive and academic performances, social life, daily activities, and professional competency, and it can increase the risk of significant public health problems. The possible justification for the higher sleep deprivation in this study area compared with others might be the differences in the educational system and the educational environment; the course delivery system, shortage of time to have a balanced student activity load, and imbalance between the course content and the time available to cover them. The location of the university, which exposes the students to different substance utilization17,18 and excessive Internet use in the current study area, was also one possible justification for this discrepancy.
This study tried to identify the factors that affect sleep quality. In our study, almost two thirds of caffeine users were sleep deprived (Figure 1), which is almost consistent with the findings in Egypt.12 Caffeine consumption, even in the afternoon, can impair the ability to fall asleep. Caffeine is an adenosine receptor antagonist and can increase arousal. Caffeine may also act on the gamma-amino butyric acid neurons of the posterior hypothalamus to suppress sleep-promoting pathways. The net effect is that caffeine increases vigilance, alertness, and deprivation.19 Alcohol consumption was found to be one of the significant factors that increase the risk of sleep deprivation in the study population. Students who drank alcohol were 66% less likely to have good sleep, which agreed with the study findings from Nepal.12 This is because even though some individuals used alcohol as a sleeping aid, alcohol promotes fragmented sleep in the latter half of the night, which further may also increase the risk for obstructive sleep apnea,32 which results in sleep disturbance and sleep deprivation. In this study, cigarette smoking was also found to be a risk factor for sleep deprivation, which agreed with the findings of other studies.10,17 This might be in part due to the fact that cigarette smoking can lead to depression, which in turn leads to sleep disturbance and sleep deprivation. This can be supported by the large proportion of students with depression who were sleep derived.
In this study, khat chewing increased the risk of sleep deprivation, which is in agreement with the findings of other studies.33 This is because khat contains cathinone and cathine, which are structurally related to amphetamine, which induces the release of serotonin and dopamine. Both increase alertness and reduce fatigue. The use of these stimulants disturbs sleep patterns, and it is conceivable that chronic use may lead to reduced sleep quality and long-term adverse health effects.34,35,36
Utilization of an electronic device before bedtime was also another determinant factor of sleep quality in our study area, which was also true in other studies. This implies that students who have been utilizing electronic devices for short period of time before bedtime were protected from being sleep deprived.37 This is due to the fact that during technology use, the blue light that is emitted from the screens of mobile phones, computers, and other devices stops the production of melatonin, the hormone that controls the sleep–wake cycle of the circadian rhythm. Reducing the amount of melatonin produced makes it harder to fall sleep and stay asleep.38 On the other hand, using electronic devices diverts the attention from initiating sleep and shortens the duration of time for adequate sleep. Moreover, students’ low CGPA was also found to be a risk factor for sleep deprivation among the students of the Institute of Health, Jimma University, which agreed with the findings of other studies. This implies that higher-scoring students were saved from being sleep deprived. Other studies indicate that there was variation in sleep quality based on students’ academic performance.39 This can be explained by the deduction that students with lower scores may be worried regarding survival and stayed awake for long periods of time in the night to study, and on the other hand, the above-mentioned factors can affect their academic performance, which will in turn lead to depression and, finally, result in sleep deprivation.
The authors conclude that sleep deprivation was common among the students of the Institute of Health, and they are under increased risk for the short- and long-term effects of inadequate sleep. Health problems, alcohol consumption, cigarette smoking, khat chewing, long-time use of an electronic device before bedtime, and low CGPA were independent predictors of sleep deprivation among the study participants. Thus, Jimma University, in collaboration with the Ministry of Education, should establish a system that limits substance utilization among health science students and develop a strategy to monitor the proper use of electronic devices. Health education should be given to increase students’ awareness on the importance of optimal sleep, quality of sleep, impact of sleep deprivation, and how to adapt to university life. Further studies on large sample sizes at the national level are needed to analyze the factors unaddressed in this study.