Types of Insomnia
A number of categorizations for insomnia has been devised over the years for clinical and research. Insomnia can be classified based on causal perspective. Insomnia can be considered as a disorder in itself (primary insomnia) or it could occur as a symptom of other disorder (secondary insomnia).
Primary InsomniaPrimary insomnia is defined as the difficulty in initiating or staying asleep or having non-restorative sleep that persists for more than a month. This type of insomnia is not attributable to physiological effects of a substance (e.g., use of drugs), medical or psychiatric cause, but rather viewed as an independent disorder.
Secondary insomniaSecondary insomnia is a symptom of an underlying illness or other conditions. There are many disorders may cause insomnia. These include sleep disorders such as apnea and narcolepsy, non-sleep condition such as heart disease, asthma and depression. Intake of alcohol, caffeine and certain drugs can also can also lead to the development of insomnia
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