Much knowledge about sleep and its disorders has accumulated in recent times, but awareness of these advances among both the general public and professionals remains inadequate. This is especially so regarding sleep disorders in children and adolescents, despite the publication of valuable sources of information relevant to clinical practice such as that by Mindell & Owens (2010).

Before the scientific study of sleep began, important observations were made by some writers. For example, Charles Dickens provided some of the best descriptions of a wide variety of sleep disorders (presumably based on his observations of real people), including some in children and adolescents (Cosnett, 1992). The most notable of these is Joe the Fat Boy in The Pickwick Papers, who might well have suffered from obstructive sleep apnoea. Dickens's accounts of this and other sleep disorders preceded those of clinicians many years later.

Although sleep medicine is now a specialty in its own right, all clinicians would benefit from having at least a working knowledge of the field. Many patients seen in both primary and secondary care are likely to have sleep problems, and these can often be treated without recourse to the special sleep centres that are now available for complicated cases. This chapter reviews main aspects of sleep and its disorders, with special emphasis on clinical practice in child and adolescent psychiatry. More detailed accounts are provided elsewhere, both in terms of children's sleep disorders in general (Stores, 2006a) and also sleep disturbance in children and adolescents who have disorders of development (Stores & Wiggs, 2001).

Only selected references to the literature are provided. In places, ‘child’ or ‘children’ can be taken to include adolescents.

Links between disturbed sleep and child and adolescent psychiatry

Sleep medicine is a multidisciplinary specialty based on approaches and information from general medicine and paediatrics, adult and child psychiatry, neuropsychiatry, psychology (including developmental aspects) and several other disciplines. Increasingly, advances are being made concerning the neurobiology of sleep, aspects of which are reflected in disorders of sleep and wakefulness (Schwartz & Roth, 2008). Mahowald and colleagues (2011) refer to wakefulness, rapid eye movement (REM) sleep and non-rapid eye movement (NREM) sleep as the ‘primary states of being’. These are not necessarily mutually exclusive states and they can occur in various combinations to produce intriguing and surprising clinical consequences in various sleep disorders.