Sleep medicine is a rapidly evolving field of medicine involving diverse types of diseases and affecting nearly all age groups. Sleep disorders are not uncommon and negatively affect morbidity, mortality, quality of life and healthcare utilization [1–3]. The International Classification of Sleep Disorders describes more than 80 different disorders, which can be effectively treated [4]. Obstructive sleep apnea (OSA), which is one of the common sleep disorders affecting 4% of middle-aged males has been linked to several serious medical complications such as hypertension, ischemic heart disease, stroke and insulin resistance [2, 3]. Interestingly, most sleep disorders can be treated when diagnosed early. Several studies in different parts of the world have demonstrated clearly that sleep disorders are highly prevalent in all age groups. A National Center on Sleep Disorders study estimated that between 50 and 70 million Americans are affected by a sleep disorder [5]. In Saudi Arabia, several studies have demonstrated that sleep disorders are prevalent among Saudis [6]. Two studies that assessed the prevalence of OSA risk and symptoms among middle-aged Saudi men and women in a primary care setting revealed that three out of ten Saudi men and four out of ten Saudi women are at a high risk of developing OSA [7, 8].

Given the magnitude of the problem worldwide, awareness regarding sleep disorders is insufficient among physicians. Thus, a significant number of patients with sleep disorders remain undiagnosed as a result of limited sleep medicine education among healthcare providers [9, 10]. One study has demonstrated that the diagnosis of sleep disorders in certain communities is less than 1%, which is considerably lower than the rates indicated by epidemiological studies [11]. A survey of primary healthcare (PHC) physicians in Saudi Arabian primary care centers revealed that only 15% of surveyed physicians have ever attended a lecture on sleep disorders [12]. Another Saudi Arabian study demonstrated that the interval between symptom onset and the diagnosis of narcolepsy was more than 8 years [13]. The authors attributed the delayed diagnosis to the fact that the diagnosis was missed by the treating clinicians in most of the studied patients [13]. Among Saudi women with OSA, other studies have suggested a more than 10-year delay between symptom onset and referral to sleep disorder centers [7, 14, 15].

Only a limited number of studies have surveyed sleep medicine education in medical schools. An earlier survey in US medical schools revealed that fewer than 2 hours were dedicated to sleep medicine education in medical schools and that 30% of the schools provided no formal sleep medicine education [16]. A more recent survey on sleep education across 12 countries in the Asia-Pacific area and the US/Canada had a poor response; only 25.9% of the surveyed schools completed the survey [17]. Overall, the average time spent on sleep education was less than 2.5 hours. Whereas certain countries provide no education in sleep medicine, developed countries (Australia and the US/Canada) spent approximately 3 hours on such education [17]. In general, most physicians receive no or minimal education on sleep medicine during medical school or residency training [12, 18]. No information is available regarding sleep medicine education in Saudi medical schools. Nevertheless, based on published data, it seems that the recognition of sleep disorders among practicing physicians in Saudi Arabia is low [6, 12].

Therefore, we conducted this study on Saudi medical schools to examine the following: 1) Sleep medicine knowledge among medical students, 2) The number of hours of teaching dedicated to sleep medicine in different courses in the curriculum related to sleep disorders and 3) The obstacles to sleep medicine education.

Then, the respondents were divided into two groups: those with high scores (≥60%) and those with low scores (<60%). Only 4.6% of the respondents were in the high score group, whereas approximately 95.4% were in the low score group. Figure 1 presents the percentages of high and low scores across sex, academic level and GPA. There was no difference between the high and low score groups with regard to sex, GPA and academic level. There was no difference between the scores of the seven universities. Figure 2 presents the mean score for students in three GPA levels (GPA ≥4, GPA between 3.00-3.99 and GPA <3.00). There was no significant difference between the three levels.

Regarding sleep medicine education, only five universities responded (KSU, KAU, KSUA-HS, DU and KKU). The number of teaching hours dedicated to sleep and sleep disorders in various courses in the responding universities ranged from 0-8 hours with a mean of 2.6 ±2.6 hours. Across all of the medical schools, the medical subcategories with the highest percentage of teaching about sleep and sleep disorders were respiratory medicine (23.1%) and physiology (23.1%), followed by internal medicine (15.4%) and ENT (15.4%), and then family medicine, psychiatry and neurology (each 7.8%).

The identified obstacles to the incorporation of sleep medicine education into the curriculum included the following: (1) sleep medicine has a lower priority in the curriculum (53%) and (2) time constraints do not allow the incorporation of sleep medicine topics (47%).

This study documents that the knowledge of sleep medicine among Saudi medical students is generally low. Moreover, the results show that sleep and sleep disorder education in Saudi medical schools is highly limited despite the substantial increase in the knowledge on and the importance of sleep medicine. Interestingly, there was no difference in the knowledge between academic levels or the different GPA groups, which may indicate that sleep medicine education is sub-optimal in medical schools. It is likely that the students who scored highly acquired their knowledge through self-study [21].

Although several studies have assessed physician knowledge regarding OSA [12, 22–25], the number of studies that assessed sleep medicine knowledge among medical students is limited. In the present study, only 4.6% of the respondents correctly answered ≥ 60% of the questions. Previous studies reported similar data for different countries. In a study that assessed the knowledge of sleep medicine among medical students in Singapore, Manhendran and Chan reported that sleep medicine knowledge was low among medical students, with 46.7% scoring between 1 and 10 out of 30, 51.7% scoring between 11-20 out of 30 and only 1.7% scoring between 21 and 30 points [21]. In another study from Croatia that used the same questionnaire, Kovacic et al. reported that the proportion of correct answers among medical students was 0.41 [26].

A recent study in China using a different assessment questionnaire revealed that Chinese medical students knew little about sleep disorders [27]. Similar results were reported among practicing physicians. A US survey demonstrated that primary care physicians do not realize the health impact of sleep disorders [11]. Another study revealed that PHC physicians rated their knowledge of sleep medicine as fair or poor [25]. A survey of PHC physicians in Saudi Arabia revealed that PHC physicians do not completely recognize the importance and impact of OSA and other sleep disorders [12]. Whereas 43% of the participants did not realize the existence of sleep medicine as a specialty, 40% felt that sleep disorders are not common [12].

The lack of knowledge regarding sleep medicine and sleep disorders among medical students is the result of the limited time assigned for teaching sleep medicine in medical schools. In addition, Teodorescu et al. reported that sleep medicine was represented in <2% of the content in 31 textbooks on four major specialties (neurology, psychiatry, pulmonary medicine and geriatrics) [28]. During 5 years of medical education in Saudi medical schools, fewer than 3 hours were allocated to teaching sleep medicine. Only five medical schools responded. This lack of response may reflect the busy schedule of the course organizers. Nonetheless, it is possible that the non-responding schools may not want to report the “limited time” or “no time” dedicated for sleep education in their schools. It is likely that the reported results overestimate the time dedicated to sleep education because the schools that did not respond were possibly less likely to have dedicated teaching time to sleep education.

A 1993 survey of medical schools in the US reported that fewer than 2 hours of the medical education curriculum were devoted to sleep and sleep disorders [16]. A more recent survey on sleep education in the medical school curriculum in 12 countries in the Asia-Pacific region and North America reported that the overall time allocated to sleep education was less than 2.5 hours [17]. Moreover, 27% of the responding schools reported that their schools provide no sleep education [17]. The US/Canada and Australia were the only countries that provided more than 3 hours of sleep education.

In the present study, the two identified obstacles to increasing the time allocated for sleep medicine education were as follows: 1) the topic’s low priority in the curriculum (53%) and 2) insufficient time (47%). In a survey by Mindell et al. across 12 countries, the following obstacles were identified: insufficient time (32%), a lack of qualified staff (24%), a lack of resources (17%), low priority (17%) and irrelevance (7%). It is of concern that despite the increased knowledge regarding the high prevalence of sleep disorders and their impact on health, 53% of the surveyed course organizers believe that sleep medicine education is a low priority for medical students.

Intuitively, the early detection and management of patients with sleep disorders depends considerably on the knowledge and awareness of practicing physicians. Because sleep medicine education in medical schools is highly limited, it is likely that sleep disorders will be under-recognized and that patients with these disorders may be inaccurately diagnosed and may receive inappropriate treatment. It has been demonstrated that doctors who receive training in sleep disorders are more likely to recognize sleep disorders [11].

A major challenge for the future is encouraging the educational system at all levels to acknowledge the high prevalence and serious consequences of sleep disorders. The curricula of modern medical schools must address a substantial amount of scientific and clinical material in a limited time. Therefore, it is difficult to devote a block for sleep and sleep disorder education. Harding et al. proposed alternative methods to integrate sleep topics into existing curriculum blocks [29]. The suggested approaches included integrating basic sleep science topics into the problem-based curricula of the preclinical years (such as physiology, neuroanatomy and neuroscience), integrating sleep history and physical signs into introductory clinical medicine and integrating sleep disorders into problem-solving sessions. These same researchers proposed the following measures for the clinical years: including sleep topics in the clinical rotations (such as internal medicine, psychiatry, family medicine and neurology), using computer-based simulations for different sleep disorders [30] and allowing students to take elective courses in sleep medicine clinics [29]. In addition, it is important to cover sleep-related material in qualifying exams, which will encourage the inclusion of sleep medicine in medical education and competency-based learning [17]. The above can be implemented in Saudi medical schools as most medical schools use the problem-based learning strategy.

In conclusion, Saudi medical students have poor knowledge of sleep medicine, which reflects the weak level of education in this field of medicine. Normal sleep is an essential component of human health and well-being. Therefore, it is essential to integrate sleep and sleep disorders into medical school education. It is hoped that medical schools will provide adequate education in sleep medicine in the near future.

AA and AQ: Medical intern. NA, KA, SB, MA and AA: Medical student. ASA: Medical education specialist. MS: data manager and statistician. AB: sleep medicine specialist.