Acad Psychiatry DOI 10.1007/s40596-014-0093-z
EMPIRICAL REPORT
The Relation Between Burnout and Sleep Disorders in Medical Students Daniel Pagnin & Valéria de Queiroz & Yeska Talita Maia Santos Carvalho & Augusto Sergio Soares Dutra & Monique Bastos Amaral & Thiago Thomasin Queiroz
Received: 11 November 2013 / Accepted: 5 March 2014 # Academic Psychiatry 2014
Abstract Objective The aim of this study is to assess the mutual relationships between burnout and sleep disorders in students in the preclinical phase of medical school. Methods This study collected data on 127 medical students who filled in the Maslach Burnout Inventory-Student Survey, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Beck Depression Inventory, and Beck Anxiety Inventory. Hierarchical logistic regressions tested the reciprocal influence between sleep disorders and burnout, controlling for depression and anxiety. Results Regular occurrence of emotional exhaustion, poor sleep quality, and excessive daytime sleepiness affected 60, 65, and 63 % of medical students, respectively. Emotional exhaustion and daytime sleepiness influenced each other. Daytime sleep dysfunctions affected unidirectionally the occurrence of cynicism and academic efficacy. The odds of emotional exhaustion (odds ratio (OR)=1.21, 95 % confidence interval (CI)=1.08 to 1.35) and cynicism (OR=2.47, 95 % CI=1.25 to 4.90) increased when daytime sleepiness increased. Reciprocally, the odds of excessive daytime sleepiness (OR=2.13, 95 % CI=1.22 to 3.73) increased when emotional exhaustion worsened. Finally, the odds of academic efficacy decreased (OR=0.86, 95 % CI=0.75 to 0.98) when daytime sleepiness increased. Conclusions Burnout and sleep disorders have relevant bidirectional effects in medical students in the early phase of medical school. Emotional exhaustion and daytime sleepiness showed an important mutual influence. Daytime sleepiness linked unidirectionally with cynicism and academic efficacy. D. Pagnin (*) : V. de Queiroz : Y. T. M. S. Carvalho : A. S. S. Dutra : M. B. Amaral : T. T. Queiroz Fluminense Federal University, Niterói, RJ, Brazil e-mail: [email protected]
Keywords Medical students . Emotional problems . Career development
University students deal with stressors such as overloaded lessons, long class schedules, and academic performance concerns. Traditionally, medical students cope with extra distressing demands such as human cadaver dissections and patients’ serious illnesses [1]. When associated with stress management difficulties, these stressors may favor the onset of burnout and sleep disorders in medical students [2–7]. Moreover, burnout and sleep disorders may also influence each other, triggering a mutual negative feedback. Student burnout is generally defined by three dimensions, namely high emotional exhaustion, high cynicism, and low academic efficacy [8]. These dimensions may promote sleep disorders such as insomnia and daytime sleepiness, which in turn worsen exhaustion and academic performance [9–11]. In the general working population, the bidirectional link between burnout and sleep disorders revealed partial contradictory results. Jansson-Frojmark and Lindblom [10] concluded that insomnia increases the risk for the maintenance of emotional exhaustion but burnout does not relate to future insomnia. However, Armon et al. [11] reported that burnout predicts future insomnia and insomnia predicts future burnout. Considering specific professional categories, the studies have addressed the unidirectional effects of burnout on sleep. White-collar workers with burnout have sleep fragmentation and marked sleepiness [12–14]; blue-collar workers with burnout have insomnia and feel tired upon waking up [15]. In the health area, workers with burnout report difficulty falling asleep, difficulty waking up, and sleep fragmentation [16]. In particular, physician assistants and primary care physicians with a high level of burnout have more insomnia and a poor sleep quality [17, 18].
Acad Psychiatry
With regard to medical students, although some studies have addressed burnout and sleep disorders [7, 19], little attention has been paid to the mutual influence between burnout and sleep disorders. The aim of this study is to assess the bidirectional relationship between burnout and sleep disorders in medical students in the preclinical phase.
Methods This study used a cross-sectional design to investigate the bidirectional association between burnout and sleep disorders, controlling for the effects of depression and anxiety. The target population consisted of second-year medical students in the Fluminense Federal University (Niterói, Brazil). Specifically, these students were enrolled in the second semester, which represents the last period of the preclinical phase. The local research ethics committee approved this study, and all participants signed informed consent forms for the research study. Data were collected by self-administered questionnaires. Roughly 30 days after the beginning of the semester, we administered the questionnaires. The standardized self-report questionnaires were the Maslach Burnout Inventory-Student Survey (MBI-SS), the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), the Beck Depression Inventory (BDI), and the Beck Anxiety Inventory (BAI). The MBI-SS is a modified version of the Maslach Burnout Inventory-General Survey (MBI-GS) that was adapted for use among students [8]. The MBI-SS addresses three burnout subscales, which are emotional exhaustion, cynicism, and academic efficacy [20]. The five items of emotional exhaustion refer to severe fatigue caused by academic demands, the four items of cynicism refer to a student’s mental distance from lessons, and the six items of academic efficacy refer to academic accomplishment. Each subscale is a continuous variable, which can be computed by the sum or the average of respective subscale items. Because of the absence of burnout normative scores in the country study, our survey established a mean score of 4 as the cutoff point. A score of 4 corresponds to a frequency of at least once a week [21], which our study considered to be a regular occurrence. Thus, this survey defined an action as a regular occurrence when the subscale score was greater than or equal to 4. Likewise, a non-regular occurrence was thought to take place when the score was under 4. In college students, the MBI-SS shows a satisfactory internal consistency [22]. The PSQI assesses sleep quality in the last month by means of 19 items that comprise seven components. These components are subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbance, use of sleeping medication, and daytime dysfunction. Each component is weighted on a 0–3 scale, and then, the seven components are summed to yield a global score that ranges from 0 to
21. A score greater than 5 points to severe difficulties in a minimum of two components or moderate difficulties in more than three components [23, 24]. The ESS evaluates the chance to fall asleep in eight everyday situations. The global score ranges from 0 to 24, showing the level of sleepiness. Scores of 11 or more mean excessive daytime sleepiness, and scores of 16 or more mean a high level of sleepiness [25, 26]. The BDI and the BAI assess, respectively, depressive and anxiety symptoms in the last week. Both scales comprise 21 self-report items, and responses are scored on a 0–3 scale describing severity levels. The total score ranges from 0 to 63, and usually, scores from 0 to 9 can be interpreted as normal, scores from 10 to 18 are thought of as being at the mild/moderate level, scores from 19 to 29 are moderate/ severe, and scores from 30 to 63 are severe [27–31]. Statistical Analysis To describe the sample characteristics, we summarize the data using descriptive statistics. To ascertain the bidirectional associations between burnout and sleep disorders in medical students, we conducted hierarchical logistic regressions, controlling for the effects of anxiety and depression symptoms. The anxiety and depression covariates were inserted in the first blocks of logistic regressions. The goodness-of-fit measure used was the omnibus test model. In the first logistic regression, we used the scores of sleep quality and daytime sleepiness as independent variables and the regular or non-regular occurrence of emotional exhaustion, cynicism, and academic efficacy as dichotomous dependent variables. Regular occurrence was established by mean scores greater than or equal to 4. In the second logistic regression, the scores of emotional exhaustion, cynicism, and academic efficacy were used as independent variables and the presence of moderate/severe difficulties of sleep and excessive daytime sleepiness as dichotomous dependent variables. According to the PSQI classification, moderate/severe difficulties with sleep mean a score greater than 5. The ESS classification defines excessive daytime sleepiness when the total score is greater than 10. A p level of 0.05 was applied for all tests, and the data were analyzed by the statistical package SPSS 17.0 for Windows.
Results Sample Characteristics The survey comprised 127 medical students, representing a response rate of 87.6 % (127/145). The mean age was 21 years (M=21.35, SD=2.27), and females represented 55 % (70/ 127) of the sample. Table 1 highlights the occurrence of
Acad Psychiatry Table 1 Levels of occurrence of burnout, depressive/anxiety symptoms, sleep quality, and daytime sleepiness of total sample (n=127)
Burnout (MBI-SS) Emotional exhaustion ≥4a Cynicism ≥4a Academic efficacy 5 (moderate/difficulties) Daytime sleepiness (ESS) 0–10 (no daytime sleepiness) 11–15 (excessive daytime sleepiness) >15 (high level of sleepiness) a
Number
Percent
76 26 22
59.8 20.5 17.3
74 39 11 3
58.3 30.7 8.7 2.4
68 30 21 8
53.5 23.6 16.5 6.3
82
64.6
47 52 28
37.0 40.9 22.0
Mean score
burnout, depressive/anxiety symptoms, sleep quality, and daytime sleepiness in the total sample. The medical students were emotionally exhausted in the preclinical phase. The mean score of emotional exhaustion was 4.15 (SD=1.08). Around 60 % of the students showed a score greater than or equal to 4, which means that they felt emotionally exhausted at least once per week. In the cynicism subscale, the students had a mean score of 2.29 (SD=1.62); nevertheless, almost 21 % of students had a score greater than or equal to 4. In the academic efficacy subscale, which is reverse scored, the students had a mean score of 3.95 (SD=0.99). Around 17 % of the students had a score under 4, that is, they felt a sense of academic accomplishment less than once per week. The students also showed depressive and anxious symptoms. Of those with depressive symptoms, most students had mild/moderate symptoms; of those with anxious symptoms, most had mild/moderate and moderate/severe symptoms (Table 1). However, considering the total sample, the mean scores of the BDI (9.63, SD=7.06) and BAI (11.84, SD= 10.24) tended toward the normal range. Finally, the medical students showed a great impairment of sleep quality and daytime sleepiness. The mean scores of the PSQI and ESS were, respectively, 6.99 (SD=3.03) and 11.96 (SD=4.46). About 65 % of the students had moderate/severe difficulties with sleep quality. Similarly, 63 % had a high level of or excessive daytime sleepiness.
Daytime sleepiness is related to insufficient sleep, which was noticeably present in our sample. Considering 7 h of average sleep [32], only 20 % (25/127) of the total sample was sleeping more than 7 h per night. Specifically, among those emotionally exhausted, only 14 % (11/76) were sleeping more than 7 h per night. Among those with daytime sleepiness, only 21 % (17/80) were sleeping more than 7 h per night. Sleep Quality and Daytime Sleepiness as Independent Variables of Burnout To assess whether sleep quality and daytime sleepiness are associated factors of burnout, we conducted a multiple logistic regression, controlling for the effects of anxiety and depression (Table 2). When the PSQI total score was used as independent variable, we found that poor sleep quality was associated strongly with cynical attitudes toward medical education (χ2 =4.33, df=1, p=0.03, omnibus test). The medical students were 1.21 (95 % confidence interval (CI)=1.01 to 1.46) times as likely to have cynical attitudes once a week when the PSQI score increased by 1 point. To clarify which components of PSQI were linked with cynicism, we performed another logistic regression with the seven components of the PSQI as independent variables, controlling for the effects of anxiety and depression. Only daytime dysfunction was associated with cynicism. The students were 2.47 (95 % CI=1.25 to 4.90) times as likely to have cynical attitudes once a week when the score of daytime dysfunction increased by 1 point. When we used the ESS score as independent variable, we found that daytime sleepiness was associated with increased emotional exhaustion (χ2 =12.67, df=1, p10
B
SE
OR (95 % CI)
p
B
SE
OR (95 % CI)
p
0.13 0.39 0.03
0.28 0.21 0.29
1.14 (0.66 to 1.96) 1.48 (0.98 to 2.24) 1.03 (0.58 to 1.82)
0.63 0.06 0.92
0.76 −0.06 0.54
0.28 0.20 0.28
2.13 (1.22 to 3.73) 0.94 (0.64 to 1.39) 1.72 (1.0 to 2.96)
0.008 0.77 0.05
Statistical significant associations in italics B beta or regression coefficient, SE standard error, OR odds ratio, p probability
Acad Psychiatry
In contrast to our findings, a study with interns did not find associations between sleep deprivation and detachment; nevertheless, daytime sleepiness and detachment worsened significantly during the internship [37]. However, in general, daytime sleepiness decreases motivation for learning [38]. In our study, this low motivation may have favored the disbelief to academic learning and, consequently, a low dedication to medical school. Dedication is the opposite of cynicism [8] and can be particularly affected by sleep deprivation. Over time, sleep deprivation decreases positive thinking and one’s orientation toward academic learning [39]. Daytime sleepiness was also associated with academic inefficacy in our study. Daytime sleepiness worsens the academic performance of medical students [9, 40], interfering with cognitive functions and self-assessment [39, 41]. The declarative memory, procedural memory, executive function, and attention are impaired in the learning process when selfimposed sleep loss occurs [7, 41–44]. The medical students with sleep restrictions have bad grades and try to counterbalance their performance with more study hours, which, consequently, increase their sleep deprivation. The learning becomes ineffective due to poor concentration, memory impairment, and deficits in abstract thinking. Thus, the medical students develop a sense of low academic efficacy, which can negatively affect their medical education [45]. Beyond interaction effects, burnout and sleep disorders were shown to be prevalent. In regard to excessive daytime sleepiness, we found a high prevalence of 63 %, which is far above the prevalence of around 20 % in the general population [46–50]. Furthermore, our prevalence rate is similar to two studies (61.6–65 %) [9, 51] and somewhat higher than two other studies (39.2–51.5 %) of medical students [2, 52]. In regard to emotional exhaustion, we also found a high prevalence of 60 %, which is again far superior to the prevalence of 24 % in the general population [53]. Considering specifically the preclinical students, our burnout prevalence is in between the rates of Minnesota (53 %) [54] and New York (71 %) [3]. However, our rate is much higher than the prevalence figures of 15 % in Nashville [4] and Seville [6]. These divergent results can be explained by response rates, moment of data collection, differences in curricula, MBI version, and burnout criteria. Our study has some limitations. We used self-report instruments, which can lead to underestimates of the problems. Another methodological shortcoming is the different periods assessed by the PSQI, ESS, and MBI-SS. Furthermore, although alcohol and sleep medication use were assessed by the scales, we did not investigate other psychoactive substances and their effects on sleep and daytime sleepiness. Addressing these issues, future works with longitudinal approach can contribute more knowledge about burnout and sleep disorders in medical students. To our knowledge, we provided the first evidence of the influence of daytime sleep dysfunction on burnout dimensions
in the preclinical years of medical school. More specifically, we revealed an important reciprocal relation between emotional exhaustion and daytime sleepiness. Early interventions in these factors can help to preclude burnout and sleep disorders and their consequences [1, 39, 45, 55–57]. Therefore, stress management programs with sleep education should be considered to prevent and treat burnout and sleep disorders in the preclinical years [58–61]. Implications for Educators • Medical students with daytime sleepiness are more emotionally exhausted, have more cynical attitudes, and have less academic efficacy. • In turn, medical students who are emotionally exhausted report more daytime sleepiness. • Burnout and daytime sleepiness can negatively impact medical learning.
Implications for Academic Leaders • Burnout and poor sleep quality have a high prevalence in the early phase of medical school. • Emotional exhaustion and daytime sleepiness have a negative mutual interaction, which can be worsened by the learning environment. • Stress management programs with sleep education should be considered in the preclinical years.
Acknowledgments The authors would like to thank Márcio Amaral de Oliveira Filho, Naira Vanessa Anomal Gonzalez, Ana Emília Teófilo Salgado, Bernardo Cordeiro e Oliveira, Caio Silva Lodi, and Raquel Muniz da Silva Melo. Disclosures On behalf of all authors, the corresponding author states that there is no conflict of interest.
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EMPIRICAL REPORT
The Relation Between Burnout and Sleep Disorders in Medical Students Daniel Pagnin & Valéria de Queiroz & Yeska Talita Maia Santos Carvalho & Augusto Sergio Soares Dutra & Monique Bastos Amaral & Thiago Thomasin Queiroz
Received: 11 November 2013 / Accepted: 5 March 2014 # Academic Psychiatry 2014
Abstract Objective The aim of this study is to assess the mutual relationships between burnout and sleep disorders in students in the preclinical phase of medical school. Methods This study collected data on 127 medical students who filled in the Maslach Burnout Inventory-Student Survey, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Beck Depression Inventory, and Beck Anxiety Inventory. Hierarchical logistic regressions tested the reciprocal influence between sleep disorders and burnout, controlling for depression and anxiety. Results Regular occurrence of emotional exhaustion, poor sleep quality, and excessive daytime sleepiness affected 60, 65, and 63 % of medical students, respectively. Emotional exhaustion and daytime sleepiness influenced each other. Daytime sleep dysfunctions affected unidirectionally the occurrence of cynicism and academic efficacy. The odds of emotional exhaustion (odds ratio (OR)=1.21, 95 % confidence interval (CI)=1.08 to 1.35) and cynicism (OR=2.47, 95 % CI=1.25 to 4.90) increased when daytime sleepiness increased. Reciprocally, the odds of excessive daytime sleepiness (OR=2.13, 95 % CI=1.22 to 3.73) increased when emotional exhaustion worsened. Finally, the odds of academic efficacy decreased (OR=0.86, 95 % CI=0.75 to 0.98) when daytime sleepiness increased. Conclusions Burnout and sleep disorders have relevant bidirectional effects in medical students in the early phase of medical school. Emotional exhaustion and daytime sleepiness showed an important mutual influence. Daytime sleepiness linked unidirectionally with cynicism and academic efficacy. D. Pagnin (*) : V. de Queiroz : Y. T. M. S. Carvalho : A. S. S. Dutra : M. B. Amaral : T. T. Queiroz Fluminense Federal University, Niterói, RJ, Brazil e-mail: [email protected]
Keywords Medical students . Emotional problems . Career development
University students deal with stressors such as overloaded lessons, long class schedules, and academic performance concerns. Traditionally, medical students cope with extra distressing demands such as human cadaver dissections and patients’ serious illnesses [1]. When associated with stress management difficulties, these stressors may favor the onset of burnout and sleep disorders in medical students [2–7]. Moreover, burnout and sleep disorders may also influence each other, triggering a mutual negative feedback. Student burnout is generally defined by three dimensions, namely high emotional exhaustion, high cynicism, and low academic efficacy [8]. These dimensions may promote sleep disorders such as insomnia and daytime sleepiness, which in turn worsen exhaustion and academic performance [9–11]. In the general working population, the bidirectional link between burnout and sleep disorders revealed partial contradictory results. Jansson-Frojmark and Lindblom [10] concluded that insomnia increases the risk for the maintenance of emotional exhaustion but burnout does not relate to future insomnia. However, Armon et al. [11] reported that burnout predicts future insomnia and insomnia predicts future burnout. Considering specific professional categories, the studies have addressed the unidirectional effects of burnout on sleep. White-collar workers with burnout have sleep fragmentation and marked sleepiness [12–14]; blue-collar workers with burnout have insomnia and feel tired upon waking up [15]. In the health area, workers with burnout report difficulty falling asleep, difficulty waking up, and sleep fragmentation [16]. In particular, physician assistants and primary care physicians with a high level of burnout have more insomnia and a poor sleep quality [17, 18].
Acad Psychiatry
With regard to medical students, although some studies have addressed burnout and sleep disorders [7, 19], little attention has been paid to the mutual influence between burnout and sleep disorders. The aim of this study is to assess the bidirectional relationship between burnout and sleep disorders in medical students in the preclinical phase.
Methods This study used a cross-sectional design to investigate the bidirectional association between burnout and sleep disorders, controlling for the effects of depression and anxiety. The target population consisted of second-year medical students in the Fluminense Federal University (Niterói, Brazil). Specifically, these students were enrolled in the second semester, which represents the last period of the preclinical phase. The local research ethics committee approved this study, and all participants signed informed consent forms for the research study. Data were collected by self-administered questionnaires. Roughly 30 days after the beginning of the semester, we administered the questionnaires. The standardized self-report questionnaires were the Maslach Burnout Inventory-Student Survey (MBI-SS), the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), the Beck Depression Inventory (BDI), and the Beck Anxiety Inventory (BAI). The MBI-SS is a modified version of the Maslach Burnout Inventory-General Survey (MBI-GS) that was adapted for use among students [8]. The MBI-SS addresses three burnout subscales, which are emotional exhaustion, cynicism, and academic efficacy [20]. The five items of emotional exhaustion refer to severe fatigue caused by academic demands, the four items of cynicism refer to a student’s mental distance from lessons, and the six items of academic efficacy refer to academic accomplishment. Each subscale is a continuous variable, which can be computed by the sum or the average of respective subscale items. Because of the absence of burnout normative scores in the country study, our survey established a mean score of 4 as the cutoff point. A score of 4 corresponds to a frequency of at least once a week [21], which our study considered to be a regular occurrence. Thus, this survey defined an action as a regular occurrence when the subscale score was greater than or equal to 4. Likewise, a non-regular occurrence was thought to take place when the score was under 4. In college students, the MBI-SS shows a satisfactory internal consistency [22]. The PSQI assesses sleep quality in the last month by means of 19 items that comprise seven components. These components are subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbance, use of sleeping medication, and daytime dysfunction. Each component is weighted on a 0–3 scale, and then, the seven components are summed to yield a global score that ranges from 0 to
21. A score greater than 5 points to severe difficulties in a minimum of two components or moderate difficulties in more than three components [23, 24]. The ESS evaluates the chance to fall asleep in eight everyday situations. The global score ranges from 0 to 24, showing the level of sleepiness. Scores of 11 or more mean excessive daytime sleepiness, and scores of 16 or more mean a high level of sleepiness [25, 26]. The BDI and the BAI assess, respectively, depressive and anxiety symptoms in the last week. Both scales comprise 21 self-report items, and responses are scored on a 0–3 scale describing severity levels. The total score ranges from 0 to 63, and usually, scores from 0 to 9 can be interpreted as normal, scores from 10 to 18 are thought of as being at the mild/moderate level, scores from 19 to 29 are moderate/ severe, and scores from 30 to 63 are severe [27–31]. Statistical Analysis To describe the sample characteristics, we summarize the data using descriptive statistics. To ascertain the bidirectional associations between burnout and sleep disorders in medical students, we conducted hierarchical logistic regressions, controlling for the effects of anxiety and depression symptoms. The anxiety and depression covariates were inserted in the first blocks of logistic regressions. The goodness-of-fit measure used was the omnibus test model. In the first logistic regression, we used the scores of sleep quality and daytime sleepiness as independent variables and the regular or non-regular occurrence of emotional exhaustion, cynicism, and academic efficacy as dichotomous dependent variables. Regular occurrence was established by mean scores greater than or equal to 4. In the second logistic regression, the scores of emotional exhaustion, cynicism, and academic efficacy were used as independent variables and the presence of moderate/severe difficulties of sleep and excessive daytime sleepiness as dichotomous dependent variables. According to the PSQI classification, moderate/severe difficulties with sleep mean a score greater than 5. The ESS classification defines excessive daytime sleepiness when the total score is greater than 10. A p level of 0.05 was applied for all tests, and the data were analyzed by the statistical package SPSS 17.0 for Windows.
Results Sample Characteristics The survey comprised 127 medical students, representing a response rate of 87.6 % (127/145). The mean age was 21 years (M=21.35, SD=2.27), and females represented 55 % (70/ 127) of the sample. Table 1 highlights the occurrence of
Acad Psychiatry Table 1 Levels of occurrence of burnout, depressive/anxiety symptoms, sleep quality, and daytime sleepiness of total sample (n=127)
Burnout (MBI-SS) Emotional exhaustion ≥4a Cynicism ≥4a Academic efficacy 5 (moderate/difficulties) Daytime sleepiness (ESS) 0–10 (no daytime sleepiness) 11–15 (excessive daytime sleepiness) >15 (high level of sleepiness) a
Number
Percent
76 26 22
59.8 20.5 17.3
74 39 11 3
58.3 30.7 8.7 2.4
68 30 21 8
53.5 23.6 16.5 6.3
82
64.6
47 52 28
37.0 40.9 22.0
Mean score
burnout, depressive/anxiety symptoms, sleep quality, and daytime sleepiness in the total sample. The medical students were emotionally exhausted in the preclinical phase. The mean score of emotional exhaustion was 4.15 (SD=1.08). Around 60 % of the students showed a score greater than or equal to 4, which means that they felt emotionally exhausted at least once per week. In the cynicism subscale, the students had a mean score of 2.29 (SD=1.62); nevertheless, almost 21 % of students had a score greater than or equal to 4. In the academic efficacy subscale, which is reverse scored, the students had a mean score of 3.95 (SD=0.99). Around 17 % of the students had a score under 4, that is, they felt a sense of academic accomplishment less than once per week. The students also showed depressive and anxious symptoms. Of those with depressive symptoms, most students had mild/moderate symptoms; of those with anxious symptoms, most had mild/moderate and moderate/severe symptoms (Table 1). However, considering the total sample, the mean scores of the BDI (9.63, SD=7.06) and BAI (11.84, SD= 10.24) tended toward the normal range. Finally, the medical students showed a great impairment of sleep quality and daytime sleepiness. The mean scores of the PSQI and ESS were, respectively, 6.99 (SD=3.03) and 11.96 (SD=4.46). About 65 % of the students had moderate/severe difficulties with sleep quality. Similarly, 63 % had a high level of or excessive daytime sleepiness.
Daytime sleepiness is related to insufficient sleep, which was noticeably present in our sample. Considering 7 h of average sleep [32], only 20 % (25/127) of the total sample was sleeping more than 7 h per night. Specifically, among those emotionally exhausted, only 14 % (11/76) were sleeping more than 7 h per night. Among those with daytime sleepiness, only 21 % (17/80) were sleeping more than 7 h per night. Sleep Quality and Daytime Sleepiness as Independent Variables of Burnout To assess whether sleep quality and daytime sleepiness are associated factors of burnout, we conducted a multiple logistic regression, controlling for the effects of anxiety and depression (Table 2). When the PSQI total score was used as independent variable, we found that poor sleep quality was associated strongly with cynical attitudes toward medical education (χ2 =4.33, df=1, p=0.03, omnibus test). The medical students were 1.21 (95 % confidence interval (CI)=1.01 to 1.46) times as likely to have cynical attitudes once a week when the PSQI score increased by 1 point. To clarify which components of PSQI were linked with cynicism, we performed another logistic regression with the seven components of the PSQI as independent variables, controlling for the effects of anxiety and depression. Only daytime dysfunction was associated with cynicism. The students were 2.47 (95 % CI=1.25 to 4.90) times as likely to have cynical attitudes once a week when the score of daytime dysfunction increased by 1 point. When we used the ESS score as independent variable, we found that daytime sleepiness was associated with increased emotional exhaustion (χ2 =12.67, df=1, p10
B
SE
OR (95 % CI)
p
B
SE
OR (95 % CI)
p
0.13 0.39 0.03
0.28 0.21 0.29
1.14 (0.66 to 1.96) 1.48 (0.98 to 2.24) 1.03 (0.58 to 1.82)
0.63 0.06 0.92
0.76 −0.06 0.54
0.28 0.20 0.28
2.13 (1.22 to 3.73) 0.94 (0.64 to 1.39) 1.72 (1.0 to 2.96)
0.008 0.77 0.05
Statistical significant associations in italics B beta or regression coefficient, SE standard error, OR odds ratio, p probability
Acad Psychiatry
In contrast to our findings, a study with interns did not find associations between sleep deprivation and detachment; nevertheless, daytime sleepiness and detachment worsened significantly during the internship [37]. However, in general, daytime sleepiness decreases motivation for learning [38]. In our study, this low motivation may have favored the disbelief to academic learning and, consequently, a low dedication to medical school. Dedication is the opposite of cynicism [8] and can be particularly affected by sleep deprivation. Over time, sleep deprivation decreases positive thinking and one’s orientation toward academic learning [39]. Daytime sleepiness was also associated with academic inefficacy in our study. Daytime sleepiness worsens the academic performance of medical students [9, 40], interfering with cognitive functions and self-assessment [39, 41]. The declarative memory, procedural memory, executive function, and attention are impaired in the learning process when selfimposed sleep loss occurs [7, 41–44]. The medical students with sleep restrictions have bad grades and try to counterbalance their performance with more study hours, which, consequently, increase their sleep deprivation. The learning becomes ineffective due to poor concentration, memory impairment, and deficits in abstract thinking. Thus, the medical students develop a sense of low academic efficacy, which can negatively affect their medical education [45]. Beyond interaction effects, burnout and sleep disorders were shown to be prevalent. In regard to excessive daytime sleepiness, we found a high prevalence of 63 %, which is far above the prevalence of around 20 % in the general population [46–50]. Furthermore, our prevalence rate is similar to two studies (61.6–65 %) [9, 51] and somewhat higher than two other studies (39.2–51.5 %) of medical students [2, 52]. In regard to emotional exhaustion, we also found a high prevalence of 60 %, which is again far superior to the prevalence of 24 % in the general population [53]. Considering specifically the preclinical students, our burnout prevalence is in between the rates of Minnesota (53 %) [54] and New York (71 %) [3]. However, our rate is much higher than the prevalence figures of 15 % in Nashville [4] and Seville [6]. These divergent results can be explained by response rates, moment of data collection, differences in curricula, MBI version, and burnout criteria. Our study has some limitations. We used self-report instruments, which can lead to underestimates of the problems. Another methodological shortcoming is the different periods assessed by the PSQI, ESS, and MBI-SS. Furthermore, although alcohol and sleep medication use were assessed by the scales, we did not investigate other psychoactive substances and their effects on sleep and daytime sleepiness. Addressing these issues, future works with longitudinal approach can contribute more knowledge about burnout and sleep disorders in medical students. To our knowledge, we provided the first evidence of the influence of daytime sleep dysfunction on burnout dimensions
in the preclinical years of medical school. More specifically, we revealed an important reciprocal relation between emotional exhaustion and daytime sleepiness. Early interventions in these factors can help to preclude burnout and sleep disorders and their consequences [1, 39, 45, 55–57]. Therefore, stress management programs with sleep education should be considered to prevent and treat burnout and sleep disorders in the preclinical years [58–61]. Implications for Educators • Medical students with daytime sleepiness are more emotionally exhausted, have more cynical attitudes, and have less academic efficacy. • In turn, medical students who are emotionally exhausted report more daytime sleepiness. • Burnout and daytime sleepiness can negatively impact medical learning.
Implications for Academic Leaders • Burnout and poor sleep quality have a high prevalence in the early phase of medical school. • Emotional exhaustion and daytime sleepiness have a negative mutual interaction, which can be worsened by the learning environment. • Stress management programs with sleep education should be considered in the preclinical years.
Acknowledgments The authors would like to thank Márcio Amaral de Oliveira Filho, Naira Vanessa Anomal Gonzalez, Ana Emília Teófilo Salgado, Bernardo Cordeiro e Oliveira, Caio Silva Lodi, and Raquel Muniz da Silva Melo. Disclosures On behalf of all authors, the corresponding author states that there is no conflict of interest.
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