Early-onset Parkinson's disease and depression.

Patients with Parkinsons disease (PD) in whom symptoms start before the age of 45 years (EOPD) present different clinical characteristics from those with the late-onset form of the disease. The incidence of depression is believed to be greater in patients with EOPD than with the late-onset form of the disease, although there is no risk factor or marker for depression in patients with PD. We studied 45 patients with EOPD to define the frequency of depression and to identify possible differences between the groups with and without depression. Depression was diagnosed in 16 (35.5%) of the patients, a higher incidence than in the population at large but similar to the figure for late-onset Parkinson disease; 8 (50%) of the patients had mild depression, 4 (25%) moderate depression and 4 (25%) were in remission. There was no relationship between depression and any of the clinical characteristics of the disease, although the EOPD patients with depression presented earlier levodopa-related complications and were more affected on the Hoehn-Yahr, UPDRS and Schwab-England scales.