The course of depressive symptoms in early Parkinson's disease.

Little is known about the course of depressive symptoms in Parkinson's disease (PD). We studied the course of clinically significant depressive symptoms using data from two clinical trials that followed 413 early, untreated PD subjects for 12 to 18 months. We measured depressive symptoms with the 15-item geriatric depression scale (GDS-15); a score of > or =5 indicates clinically significant depressive symptoms. We used a time-dependent Cox model to examine the association between demographic variables, PD severity, and medication use on the time to resolution of depressive symptoms. One hundred fourteen of 413 (27.6%) subjects were screened positive for depression during the study, with a median GDS-15 score of 6, indicating mild symptoms. Within 6 months, 47% of subjects experienced remission of clinically significant depressive symptoms. Subjects with mild depressive symptoms were more likely to develop moderate to severe depressive symptoms (GDS > or = 10) than those without prior symptoms (relative risk = 6.16). Increasing severity of depressive symptoms, older age, and longer PD duration predicted a lower likelihood of symptom resolution (hazard ratios 0.83-0.92). Mild depressive symptoms have a variable course, with remission and development of more sustained and severe symptoms occurring over time. More severe depressive symptoms may herald a protracted course.

Obsessive-compulsive disorder in Tourette's syndrome.

A substantial body of scientific evidence suggests that obsessive-compulsive behavior occurs in a large percentage of patients with TS. Reliable estimates suggest that nearly 50% of patients with TS have some degree of obsessive-compulsive features. Most patients with TS have only mild OCB and thus would not meet the DSM-IV diagnostic criteria for OCD. Therefore, OCB is perhaps a more appropriate characterization of this behavioral phenomenon that occurs in TS. OCB in TS appears similar to the spectrum of the tic disorder in terms of its onset, severity, and course. As with tics, OCB is typically mild and not always substantially disabling. Although clinical features between TS + OCB and primary OCD overlap considerably, patients with TS + OCB appear to experience different types of obsessive thoughts and compulsive rituals. Compelling genetic evidence suggests that OCB may be an alternative expression of the TS phenotype, which may selectively affect female gene carriers. Identifying the TS gene in the future will substantially broaden our knowledge of this intriguing neurobehavioral disorder. Finally, neurobiologic evidence points to similar anatomic and chemical substrates in the pathogenesis of TS and OCD, suggesting that these two disorders share a common pathophysiology. The clinical evaluation of patients with TS and their families should always include an assessment for OCB. Self-rated inventories of OCD such as the LOI, LOI-CV, and MOCI are useful screening scales. A more structured interview using the Y-BOCS (CY-BOCS) is useful for determining the degree and severity of OCB in TS as well as the response to therapy. Clinicians should keep in mind that OCB may be the most disabling feature of TS and may require treatment. Pharmacologic agents, such as SSRIs, and traditional behavioral therapy are proven effective treatments for OCB, which can substantially reduce the full effect of TS on patients and their families.