Insomnia usually comprises one or more of the following:6

·       inability to fall asleep;

·       inability to stay asleep;

·       frequent waking through the night;

·       long periods of wakefulness through the night;

·       an inability to nap during the day even when feeling tired.

Whatever the form of sleep disturbance, it results in feeling tired and unrefreshed when getting up the next day

The European Sleep Research Society first published the 'European guideline for the diagnosis and treatment of insomnia' in September 2017. This refers to the International Classification of Diseases (ICD-10) definition of insomnia which has main diagnostic criteria as:

·       the presence of disturbed sleep onset or sleep maintenance, or poor sleep quality;

·       sleep disturbances occur at least three times a week over a period of a month;

·       the patient dwells on their sleep disorder, especially during the night, worrying about the negative consequences of insomnia;

·       there is a high degree of suffering or daily activities are impaired.

The ESRS guideline also cites the International Classification of Sleep Disorders (ICSD-3) which provides further diagnostic criteria. For a diagnosis of a clinically relevant disorder, ISCD-3 says the sleep disorder should occur at least three nights a week for a period of three months.

An ongoing health survey found that 5.8% of the 20,503 adult respondents met insomnia diagnosis criteria in 2012. There had also been €a modest but steady increase in prevalence€ over the 15 years since the survey was first conducted.18