Weekly SCD Practice Update

Advanced neuroimaging in adults with sickle cell disease (SCD) revealed elevated cerebral blood flow (CBF), reduced cortical amplitude of low-frequency fluctuation (ALFF), increased white-matter ALFF, and altered functional connectivity — patterns associated with slower cognitive processing and higher pain sensitivity.

Key Findings

  • Purpose
    To characterize CBF, ALFF, and resting-state functional connectivity in adults with SCD compared with matched healthy controls, and relate these measures to cognition and pain sensitivity.
  • Population
    Adults with SCD and matched healthy controls, as specified in the study.
  • Headline Result
    • Adults with SCD demonstrated significantly elevated resting CBF compared with controls.
    • Cortical ALFF was reduced, indicating lower spontaneous low-frequency activity in gray matter regions.
    • White-matter ALFF was increased, reflecting higher low-frequency signal fluctuation within white-matter regions (as measured, without mechanistic interpretation).
    • Resting-state analyses showed altered functional connectivity patterns relative to controls.
    • These imaging findings correlated with slower processing speed and increased pain sensitivity.
  • Why It Matters
    These results add to evidence that adults with SCD may experience subtle, chronic alterations in brain activity and connectivity that can influence cognitive efficiency and pain perception — even in the absence of overt cerebrovascular events. Such physiologic patterns may help clinicians better understand cognitive and sensory challenges reported by patients.
  • Evidence Gaps
    Cross-sectional data cannot infer causality; sample characteristics may limit generalizability; and the study does not track longitudinal change, treatment effects, or everyday functional outcomes. ALFF findings describe measured signal differences but do not establish underlying mechanisms.

Source: Journal of Sickle Cell Disease“Altered cerebral blood flow and functional connectivity in adults with sickle cell disease.”

Regulatory & Guideline Watch

Existing SCD guidelines primarily address stroke prevention and silent infarct monitoring. They do not include recommendations for cerebral perfusion assessment or resting-state functional measures such as ALFF. As more evidence emerges, neurocognitive surveillance in adults with SCD may become an area for future guideline evolution.