Parkinson's disease in blacks. Observations on epidemiology in Natal.

Black patients with idiopathic Parkinson's disease (PD) present for neurological consultation much less frequently than white or Indian patients. That this is due to true rarity of PD among blacks is suggested by the observation that blacks with motor neuron disease and secondary parkinsonism are treated in numbers comparable with whites and Indians. These conclusions are derived from a series of 2,638 inpatient neurological consultations and from data on levodopa usage in three major hospitals in Durban. Lower life expectancy and failure of old people to attend hospital may be factors in the apparent low prevalence of PD among blacks, but other undetermined factors must play a part.