Introduction

Chronic insomnia and poor sleep quality are among the most common ailments that healthcare professionals manage, although epidemiological estimates vary depending on the definition used and the population studied. For example, a survey of 1746 patients aged between 20 and 60 years found that 6.8% and 9.7% reported insomnia at baseline and at follow-up a year later respectively. Insomnia was still present after a year in 44.4% of patients with insomnia at baseline.

A UK study suggested a higher prevalence: 37% of 2363 responders reported insomnia. Fifteen per cent of those without insomnia at baseline reported the condition at the 12-month follow up. Anxiety, depression, and pain at baseline seemed to be associated an increased risk of developing insomnia. Furthermore, 69% of those with insomnia at baseline still reported the sleep disturbance after 12 months. Older people were especially likely to report persistent insomnia. Indeed, insomnia and poor subjective sleep quality become more common with advancing age. Around half of elderly people report insomnia and dissatisfaction with their sleep quality.

References

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Lemoine et al, 2007 Prolonged-release melatonin improves sleep quality and morning alertness in insomnia patients aged 55 years and older and has no withdrawal effects. J Sleep Res 2007-16:372/380