Insomnia secondary to medical and psychiatric disorders

Medical or psychiatric disorders or shift work are risk factors that can lead to insomnia.

Most subjects with insomnia have a psychiatric pathology (usually anxiety or depression) or a history of substance abuse, although neurological diseases such as Parkinson’s disease, dementia or epilepsy also cause difficulty sleeping.

Other chronic diseases that manifest with pain (e.g., fibromyalgia), itching, dyspnea (respiratory distress that may exist in asthmatic subjects, with chronic bronchitis and other respiratory diseases), gastroesophageal reflux or have nocturnal symptoms (e.g., nocturia, characteristic of prostatic hypertrophy) are frequent causes of insomnia.

In addition, most primary sleep disorders (sleep apnea syndrome, restless legs syndrome, circadian rhythm disorders, etc.) involve difficulty sleeping.