Sickle Cell Anaemia Linked to Accelerated Brain Ageing and Cognitive Decline: Study

New Delhi: Researchers at Washington University School of Medicine in St. Louis have explored how sickle cell anaemia (SCA) and socioeconomic status impact brain health and cognitive function.

The study, published in JAMA Network Open on January 17, 2025, focuses on the "brain age gap" (BAG), which measures the difference between a person’s chronological age and their estimated brain age.

Adults with SCA had a much higher median BAG (14.2 years) compared to healthy individuals (7.3 years), showing signs of premature brain ageing. "This larger brain age gap in SCA suggests insufficient brain growth, premature aging, or both," explained Dr. Andria L. Ford, the study’s lead author.

Economic deprivation, measured by the Area Deprivation Index (ADI), was linked to higher BAG in both groups. People from poorer backgrounds showed more significant premature brain ageing, which also correlated with lower scores in cognitive skills such as executive function, processing speed, and full-scale IQ.

The study included 230 participants (123 with SCA and 107 controls) who underwent brain MRIs and cognitive tests. Researchers used DeepBrainNet, a deep learning model trained on over 14,000 brain scans, to estimate brain age.

"By leveraging advanced imaging and modelling techniques, we were able to pinpoint how socioeconomic factors and chronic disease intersect to accelerate brain ageing," said Dr. Ford.

The findings highlight the potential of brain age modelling as a tool for identifying individuals at risk of cognitive decline. "Brain age modelling may serve as a valuable biomarker for identifying individuals at risk of cognitive decline, particularly in underresourced settings," noted co-author Dr. Melanie E. Fields.

Additionally, white matter mean diffusivity (MD), another brain imaging metric, was found to be a stronger predictor of cognitive performance in SCA patients than BAG.

While the study offers valuable insights, the authors noted limitations such as its cross-sectional design and small sample size. Long-term studies are underway to confirm these findings.

"Our ultimate goal is to develop effective strategies for mitigating cognitive impairment in both SCA and economically disadvantaged populations," Dr. Ford concluded. "This study is a crucial step toward that goal."

Dr. Ford summarized the study’s significance: "Adults with SCA are living into mid-adulthood with signs of premature brain ageing. Beyond the impact of chronic disease, economic deprivation plays a critical role in brain development, ageing, and cognitive function."

Dr. Fields added: "The correlation between BAG and cognitive outcomes underscores the importance of addressing both medical and socioeconomic factors in improving brain health."

This research highlights the complex relationship between health, economic status, and brain function, paving the way for targeted interventions to improve lives.