White matter hyperintensity volume in late-onset and early-onset schizophrenia

Background. Late life onset schizophrenia (sometimes termed 'late paraphrenia') has been theorized to be due to neuro-degenerative processes affecting individuals with latent vulnerability to schizophrenia. However, neuro-imaging studies using computed tomography (CT) and magnetic resonance imaging (MRI) investigating possible degenerative anatomic correlates (atrophy, white matter disease, and strokes) to late onset psychoses have yielded conflicting findings. The variation in these findings may be due to differences in study design, case ascertainment, and measurement methods. Objective. The present study compares a continuous measure of total volume of white matter hyperintensities (WMHs) in age, race, and gender-ratio matched groups of late-onset schizophrenic, elderly, early-onset schizophrenic and control subjects. Method. Our method of WMH measurement yielded an explicit volume and is an alternative to frequently used ordinal measures. Results. We found no significant differences in the WMH volumes between these three groups. This finding is consistent with a prior study (Symonds et al., 1997. J. Neuropsychiat Clin Neurosci 9: 251-258), that used ordinal measures.