The two main categories of hypersomnia or excessive sleep disorder are primary hypersomnia and recurrent hypersomnia. Primary hypersomnia is also known as idiopathic hypersomnia and is characterized by excessive daytime sleeping over a long period of time. These symptoms are present most of the time and may cause the patient to sleep at undesirable or unexpected times, usually in waking activities such as at work, in a conversation, while eating or walking. Idiopathic hypersomnia disrupts the normal functioning of the individual at work, family and social settings.

The main difference between primary hypersomnia and recurring hypersomnia is that in the latter the individuals experience prolonged periods of sleep where they do not show any signs of hypersomnia, whereas individuals with the former type are affected by it most of the time. The problems arising from idiopathic hypersomnia include daytime drowsiness, irritability, restlessness, inability to concentrate and anxiety.

Causes for Idiopathic Hypersomnia:

There are various causes for this disorder:

Feelings of daytime sleepiness are associated with excessive use of caffeine, alcohol and several other medications.

Shift work and insomnia are also leading factors that contribute to the development of this disorder as they lead to the disruption of the body’s natural sleep cycle.

Lack of nighttime sleep can cause excessive daytime sleepiness.

Individuals with this disorder often have problems waking up in the morning and staying awake during the day.

Patients tend to nap frequently and do not feel refreshed on waking up.

Approximately 5% of the adult population is affected by hypersomnia of which about 5 to 10 percent are diagnosed with Idiopathic hypersomnia. The age of onset of the disorder is between 15 and 30 years and does not begin suddenly but gradually, sometimes over the years.

Diagnosis:

In order to meet the diagnostic criteria of this disorder, the patient must have symptoms of excessive daytime sleeping for at least a month leading to the interference with his/her normal activities.