Total cerebral blood flow in relation to cognitive function: the Rotterdam Scan Study.

Cerebral hypoperfusion has been associated with worse cognitive function. We investigated the association between cerebral blood flow and cognition and whether this association is independent of brain volume. In 892 participants, aged 60 to 91 years, of the population-based Rotterdam Scan study, we measured total cerebral blood flow (tCBF) and brain volume using magnetic resonance imaging. Lower tCBF was associated with worse information-processing speed, executive function, and global cognition. However, after correcting tCBF for brain volume, these associations disappeared. The association between tCBF and cognition may be mediated or confounded by brain atrophy. Future studies on tCBF should take into account brain atrophy.