Reduced functional connectivity induced by longitudinal alterations of
structure and perfusion may be associated with cognitive impairment in
patients on maintenance hemodialysis
Abstract
Background: Hemodialysis (HD) leads to cognitive impairment; however,
the pathophysiology of maintenance HD remains unclear. This study aimed
to investigate the longitudinal alterations in gray matter volume (GMV)
and cerebral blood flow (CBF) in patients on follow-up HD compared with
baseline HD, examine the alterations in functional connectivity (FC) by
defining co-changed brain regions as seed points, and investigate the
correlation between the co-changed brain regions and neuropsychological
test scores. Methods: Twenty-seven patients with HD and 30 healthy
controls were enrolled in this study. All participants underwent
high-resolution T1-weighted imaging, arterial spin labeling, and
functional MR imaging to measure GMV, CBF, and FC. The patients on HD
were assessed at baseline and 3 years subsequently. Results: The right
and left medial superior frontal gyrus (SFGmed.L) exhibited
significantly lower GMV and CBF in patients on follow-up HD compared
with patients on baseline HD and lower FC between the SFGmed.L and left
middle temporal gyrus (MTG.L). Decreased FC between the SFGmed.L and
MTG.L was positively correlated with neuropsychological test scores in
the follow-up HD group. Conclusions: Reduced GMV and CBF may result in
decreased FC between the SFGmed.L and MTG.L, which may be associated
with cognitive impairment in patients on maintenance HD. Our findings
provide unique insights into the pathological mechanisms of patients on
maintenance HD with cognitive impairment.