THE HACHINSKI ISCHEMIC SCORE - A REEVALUATION

The Hachinski Ischaemic Score (HIS) was first introduced in 1975 as a clinical scale intended to differentiate cases of dementia resulting from multiple strokes (multi-infarct dementia) from those with primary degenerative dementias. Its conceptual basis rests on the view that vascular dementia is the result of strokes, not of general atherosclerosis or ischaemia. This article critically examines the psychometric properties of the scale. Reliability studies are singularly lacking, and studies of its validity have produced inconsistent findings. Furthermore, there has been a change of views regarding vascular dementia, which is currently seen as heterogeneous and not simply a consequence of strokes. We argue that the HIS is in fact an infarct score, that it is not a true dimensional scale, and that it has outlived its usefulness.