OLFACTORY FUNCTION IN RESTLESS LEGS SYNDROME

Restless leg syndrome (RLS) is usually idiopathic but may occur in pat ients with Parkinson's disease (PD). Both respond to dopaminergic medi cations. Whether these disorders share a common pathophysiology is unc lear. Because PD is associated with a loss of olfactory function, we c ompared the olfactory function of patients with RLS with control and P D patients. Using the University of Pennsylvania Smell Identification Test (UPSIT), olfactory function was found to be normal in patients wi th idiopathic RLS and significantly reduced in patients with PD. This suggests that the pathophysiology of RLS differs from PD, and that RLS likely is not a ''forme fruste'' or a preclinical sign of PD.