Reduced striatal glucose consumption and prolonged reaction time are early features in Huntington's disease.

Striatal glucose consumption was measured by positron emission tomography in 4 male patients, aged 16-27, suffering from Huntington's disease and in 3 age-matched control subjects. Symptoms had been present for 3 years or less; they were mainly psychiatric. Two of the patients had no chorea although the time taken to initiate a movement was prolonged and there was some reduction in the speed at which movements could be executed. Caudate atrophy was absent or minimal by CAT scan yet striatal glucose consumption was markedly reduced in all of the patients. It is suggested that striatal glucose consumption is largely determined by the functional integrity of spiny neurones in the striatum.