Narcolepsy has thus often been associated with psychiatric disturbance, but surveys have produced contradictory results. Schizophrenia has been found at rates ranging from 0% to 14% and depression at rates ranging from 5% to 30 %.9,21-23 Krishnan et al,23 for example, showed that two thirds of narcoleptic patients had psychiatric disorders according to Diagnostic and Statistical Manual of Mental
Health, Third Sirtuin inhibitor Edition (DSM-III) criteria, including adjustment disorder, major depressive episode, alcohol dependence, and personality disorder. However, those studies were made in small samples,22,23 with no control group,21-23 Inhibitors,research,lifescience,medical often based on case notes and in patients taking amphetamines, which were, until recently, the mainstay of treatment for narcolepsy. Inhibitors,research,lifescience,medical The well-documented side effects of amphetamines (including increased feelings of anxiety, irritability and agitation, sexual dysfunction, and insomnia) may exacerbate existing or underlying psychiatric conditions.24 In a recent study, Vourdas et al25 investigated the frequency of major and minor psychiatric disorders among patients with narcolepsy, as compared with a group of matched normal individuals, using a detailed
structured psychiatric Inhibitors,research,lifescience,medical diagnostic interview. This study took advantage of the recent introduction of the wake-promoting drug modafinil, which improves vigilance via a nondopaminergic/adrenergic mechanism and does not appear to induce psychosis. This study found little evidence for an increased frequency of psychotic disorders in narcolepsy. Although Inhibitors,research,lifescience,medical four patients (out of 45) had experienced episodes meeting criteria for probable psychotic disorder (in contrast to none of the controls), there were clear indications that the psychotic symptoms were related
to amphetamine use in the past, since they Inhibitors,research,lifescience,medical disappeared when the dose was lowered or medication was changed to modafinil. None of the patients taking modafinil showed psychotic symptoms. They found that 24% of patients had criteria for simple depression, a rate similar of that found in other surveys in unless narcolepsy1,2,7 and chronic medical disorders in general.26 Although some studies have shown a possible therapeutic role of stimulant medication for improving affect,27 others have shown that depression in narcolepsy is independent of pharmacological treatment or did not improve after treatment.1 Goswami28 reported that, despite treatment for excessive daytime sleepiness, narcolepsy patients remain at significant risk for psychiatric and psychosocial limitations. Beusterien et al8 have shown that treatment with modafinil produces higher scores than placebo for the physical role, energy/vitality, social function, and emotional role on the SF-36.