The effects of hypertension and body mass index on diffusion tensor imaging in schizophrenia.

Recently, the negative effects of hypertension and elevated body mass index on cognitive functioning in schizophrenia have been reported (Friedman et al., 2010). Data suggests that cognitive changes in hypertensive patients from the general population may be mediated, in part, by white matter damage. Therefore, we performed diffusion tensor imaging (DTI) in the same subjects studied by Friedman et al. (2010) to investigate the effects of hypertension and elevated body mass index on the fractional anisotropy (FA) of several major white matter tracts. Significant interactions between a diagnosis of schizophrenia and hypertension on FA in several white matter regions were detected. Hypertension was associated with lower FA in the schizophrenic group and higher FA in the same tracts in the non-schizophrenic subjects. These results suggest hypertension-induced compensatory mechanisms in the brains of non-schizophrenic patients with hypertension which may be impaired in persons with schizophrenia.