The quantity, quality and timing of sleep are affected by many everyday activities and attitudes (

Table 1.4).

The importance of these in assisting or interfering with sleep is generally underestimated. In developed societies sleep is being increasingly squeezed into the time left over after family, social, work and recreational activities with the result that insomnia, excessive day- time sleepiness and other sleep symptoms are becoming increasingly common.

The aim of sleep hygiene is to translate an understanding of the nature and the control of sleep into practical advice about how to promote this through changes in lifestyle and the environment.

Sleep hygiene is useful in a wide range of sleep disorders and combines advice about homeostatic, adaptive and circadian aspects of sleep control, how to avoid sleep deprivation, and how to respond to awakenings from sleep if these occur. Some aspects
of sleep hygiene fall into more than one of these categories, but in general it entails the following.

1 Altering the sleep environment so that the bed is comfortable and the bedroom warm, dark and quiet.

2 Improving sleep–wake patterns. Increasing the physical activity during the day; preparation for sleep (for instance by mentally winding down and taking a hot bath); regular meals and sleep and wake times, and avoiding daytime and evening naps may all be of help.

3 Changing drug intake. Avoiding caffeinated drinks in the evening and discontinuing other stimulants, such as glucocorticoids, and altering the timing of diuretics in order to minimize nocturia may all be of benefit.

References