Table 1 Factors related to chronic insomnia

Specific sleep disturbances:

   • Circadian rhythm disorders:

◦ Advanced sleep-phase syndrome

◦ Delayed sleep-phase syndrome

   • Sleep apnea (obstructive, central, or mixed)

   • Restless leg syndrome

   • Periodic limb movement disorders (nocturnal myoclonus)

   • Parasomnias, i.e. REM-sleep-behavior-disorder

Physical illness:

   • Pain: arthritis, musculoskeletal pain, other painful conditions

   • Cardiovascular: heart failure, nocturnal breathlessness, nocturnal angina

   • Pulmonary: chronic obstructive pulmonary disease, allergic rhinitis (nasal obstruction)

   • Gastrointestinal: gastroesophageal reflux disease, peptic ulcer disease, constipation, diarrhea, pruritus ani

   • Urinary: nocturia, incomplete bladder emptying, incontinence

   • Central nervous system: stroke, Parkinson disease, Alzheimer disease, seizure disorder

   • Psychiatric illness: anxiety, depression, psychosis, dementia, delirium

   • Pruritus

   • Menopause (hot flushes)

Behavioral: daytime nap, early retirement to bed, use of bed for other activities (eg, reading and watching television), heavy meals, lack of exercise, and sedentary lifestyle

Environmental: noise, light and other disturbances, extreme temperatures, uncomfortable bedding, and lack of exposure to sunlight

Medications:

   • Central nervous system stimulants: sympathomimetics, caffeine, nicotine, amphetamines, ephedrine, phenytoin

   • Antidepressants: bupropion, selective serotonin reuptake inhibitors, venlafaxine

   • Anti-Parkinsonian agents: levodopa

   • Bronchodilators: theophylline

   • Cardiovascular: B-blockers, diuretics

   • Histamines, H₂ blockers: cimetidine

   • Anticholinergics

   • Corticosteroids

   • Alcohol

   • Herbal remedies

   • Stimulant laxative