O sleep, O gentle sleep,
Nature's soft nurse, how have I frighted thee,
That thou no more wilt weigh my eyelids down
And steep my senses in forgetfulness?.
William Shakespeare, King Henry IV, Part II
Me thought I heard a voice cry "Sleep no more!
Macbeth does murder sleep," the innocent sleep,
Sleep that knits up the ravell'd sleave of care,
The death of each day's life, sore labor's bath,
Balm of hurt minds, great nature's second course,
Chief nourisher in life's feast
William Shakespeare, Macbeth
Shakespeare's lines are merely examples of the importance of sleep, both normal and disrupted, in the literary canon. Nevertheless, despite the recognition of its importance both biologically and metaphorically by poets and playwrights, many neurologists spend far too little time contemplating the subject and addressing patients' concerns about their sleep. This is all the more surprising considering the amount of time spent-or, if disrupted, not spent-in the sleep state, as well as the frequency of patient complaints. This issue of Continuum, under the chairmanship of Dr Michael Thorpy, should go far to cure any deficiencies you may feel about your ability to recognize and alleviate your patients' symptoms. The issue begins with the current classification of sleep disorders by Dr Imran Ahmed and Dr Thorpy. This is followed by a comprehensive explication of normal sleep, throughout the lifespan, by Dr Madeleine Grigg-Damberger, who will introduce you to the recently revised classification of sleep stages. Included in her chapter are a number of pearls that will emphasize the importance of sleep, both REM and non-REM, and help explain why Shakespeare was correct in recognizing its critical nature when he called sleep the "chief nourisher in life's feast." Dr Grigg-Damberger will also help you understand the metabolic importance of sleep and perhaps introduce you to some unfamiliar hormones, such as leptin and ghrelin.
The remainder of the issue highlights many important specific disorders of sleep. Dr Michael Silber provides a modern and specific approach to insomnia, a subject appropriately placed first because of its prevalence. Again, the Bard's plaintiff wail from King Henry the Fourth emphatically reflects patients' despair when they are (or feel) unable to sleep. Dr Silber includes an important discussion of proper sleep hygiene, a critical educational intervention you can make with many of your patients with insomnia. By the way, sleep hygiene dictates that you should not be reading this issue of Continuum in your bed, and certainly you will not find it soporific! Dr Thorpy addresses recent advances in our understanding and management of narcolepsy, emphasizing the role of hypocretin and the use of the new agent sodium oxybate for treatment of narcolepsy associated with cataplexy.
In recent years, restless legs syndrome (RLS) has gained increasing recognition and prominence. Dr Arthur Walter addresses this entity, emphasizing its prevalence, its clinical features, its association with other important neurologic disorders, and its management. RLS remains an underdiagnosed and undertreated condition. You will be able to make a major difference in the lives of many patients after mastering the subject. Drs Allison Chan and Clete Kushida discuss the important subject of sleep-disordered breathing, primarily emphasizing obstructive sleep apnea, but also including central sleep apnea. Finally, among the specific sleep disorders, Drs Bradley Vaughn and O'Neill D'Cruz explore the fascinating realm of parasomnias and other peculiar nocturnal events. These include not only the well-recognized phenomenon of sleepwalking, but less clearly recognized entities such as night terrors (pavor nocturnes) and exploding head syndrome. Often these parasomnias do not require specific treatment, but accurate diagnosis is important in making that determination and allowing appropriate reassurance to patients and their families.
The issue also includes an ethical perspective in which Dr Jeffrey Ellenbogen provides a thoughtful discussion on the issue of doctor-patient relationships, particularly focused on a patient's request for medication. Finally, you can hone your knowledge by tackling the patient management problem, constructed by Dr Ahmed, and the multiple-choice questions, which have been carefully crafted for this issue by Drs Julie Hammack and Joanne Lynn.
We are grateful to Dr Thorpy and his faculty for bringing us up to speed on a medical topic that we too often neglect. "To sleep, perchance to dream…" But not before you have put away your copy of Continuum for the evening.
Aaron E. Miller, MD