Lower body parkinsonism: evidence for vascular etiology.

We studied 10 patients with marked gait difficulty and no or only minimal upper limb involvement, defined here as lower body parkinsonism (LBP). They were compared to a control group of 100 patients with otherwise typical Parkinson's disease (PD). Both groups were of comparable age, but the mean duration of symptoms was significantly shorter in the LBP group (2.6 +/- 1.5 years versus 7.5 +/- 4.9 years). Gait disturbance was the initial symptom in 90% of LBP patients, as opposed to 7% of controls. Hypertension was present in 70% of LBP patients, and only 22% responded to levodopa. In contrast, only 21% of controls had a history of hypertension, and 96% improved with levodopa. We conclude that these 10 LBP patients constitute a homogenous group, distinct from typical PD. Besides their disproportionate gait disturbance, they are distinguished from PD patients by more rapid progression, higher incidence of hypertension, and a poor response to levodopa. Ischemic etiology for LBP is supported by abnormal neuroimaging studies.