Insomnia Is Linked with Mental Illness

Although insomnia is the most commonsleep complaint, the condition frequently isunderdiagnosed and undertreated. The lack ofan insomnia diagnosis is probably due to thefailure to recognize the relationship betweenpsychiatric illness and insomnia.

Sleep disturbance is a part of the diagnosticcriteria for many mental disorders, includingmood disorders and anxiety disorders.Insomnia also is strongly associated withpsychiatric disorders in the general population.On the Minnesota Multiphasic PersonalityInventory, 79.3% of the patients with insomniawere positive on at least one clinical scale. Theassociation between insomnia and psychiatricillness is even stronger in the clinical population.A multicenter study found that 75% ofpatients in sleep clinics or in primary medicalclinics could be diagnosed as having psychiatricdisorders.

The appropriate diagnosis is crucial for thetreatment of presenting symptoms of insomnia,as well as underlying psychiatric disorder.The diagnostic approach for a patient withchronic insomnia includes obtaining a sleephistory, a medical history, a psychiatric history,a mental status examination, a physical examination,and a history of substance abuse.Although sleep laboratory testing normally isnot included, it should be considered ifobstructive sleep apnea or restless legs syndromeis suspected.