Abstract

Axial rotation during recumbency was used to quantify the tendency towards parkinsonism with respect to one cardinal sign, brady/hypokinesia. Twenty-four elderly sufferers from idiopathic parkinsonism, their spouses, and 40 control subjects were studied. Significant differences in total angular displacement over 7 h were found between sufferers and their spouses (83% of grand mean) and between spouses of sufferers and controls (31%). These differences could not be accounted for by age or cognitive function. Moreover, the total angular displacement of the spouses was independent of whether they shared a bed with the sufferer. Neither the sufferers and their spouses, nor the 20 couples who constituted the control group, showed any relationship between partners with respect to angular displacement. These findings do not favour learned behaviour, or selective mating as an explanation of reduced movement in spouses of sufferers. Significantly more of the control couples had a single cardinal sign in both partners than expected on the basis of the frequency of a single sign in one partner. Environmental factors operating in adult life could be involved in the pathogenesis of parkinsonism.