Gender differences Gender differences have also been

documented with respect to the severity and symptom profiles of unipolar depression among children, adolescents, and adults although no compelling gender effects were found on the salient features.62,67,70-73 Among both adolescents and adults, females typically report higher levels of symptoms.70,74 Inhibitors,research,lifescience,medical With regard to symptom patterns, somatic symptoms, such as changes in appetite and weight, sleep problems, and psychomotor retardation are more common in females.73,75-78 Increased crying, feelings of failure, guilt, poor self-esteem, and other cognitive symptoms may also be more frequent in females.75-77,79-81 In contrast, depressed males more frequently report anhedonia, diurnal variation in mood and energy, social withdrawal, and work impairment.75,76,80 The reasons for gender differences in Inhibitors,research,lifescience,medical unipolar depression are not well understood. One model suggests that

females are more prone to exhibit a cognitive style characterized by negative self-evaluation and rumination.82,83 Gender differences in brain function have also been postulated as one potential reason for the symptom variability.84,85 Comorbidity Both clinical and epidemiological studies have shown that up to 40% to 70% of children and adolescents with depression also suffer from another psychiatric disorder, and many youngsters have two or more comorbid diagnoses.86-88 Approximately 70% Inhibitors,research,lifescience,medical of children and adolescents with dysthymic disorder will eventually develop an episode of major Inhibitors,research,lifescience,medical depressive disorder, resulting in “double depression.”89,90 Other frequent comorbid diagnoses include anxiety disorders, disruptive disorders, and substance use disorders. Although it is not clear whether these comorbid conditions

represent a developmental sequence, shared genetic or environmental risk Azacitidine factors or a separate subtype of the disorder, it is likely that Inhibitors,research,lifescience,medical one or more of these factors contribute to comorbidity.86,91 Age and gender can influence the patterns of comorbidity88,92 Specifically separation anxiety disorder and attentiondeficit hyperactivity disorder are more common in children, whereas conduct disorder, panic disorder, and substance abuse are more common in adolescents.92,93 Similarly, disruptive and substance use disorders arc less likely, and eating disorders are more likely, in girls than boys.10,21,88,92 The presence of comorbidity Tryptophan synthase has important clinical and functional implications.63,94 In particular, youth with comorbid dysthymia and major depression had more severe and longer depressive episodes, and higher frequency of suicidally and social impairment than those who had a single mood disorder.90,95,96 Similarly, comorbid anxiety disorder was associated with increased severity and duration of depressive symptoms, increased suicidally, poor response to psychotherapy, and elevated risk for addictive disorders.