Study Links Lower Bone Density to Cognitive Decline and Brain Changes

Recent research from Johns Hopkins University has identified a connection between lower spinal bone mineral density and both cognitive decline and age-related brain changes. Published in the journal Radiology, the study advances our understanding of how bone health may interrelate with cognitive function.

The research team, led by Dr. Sara Momtazmanesh in the Department of Radiology and Radiological Sciences, utilized data from the Multi-Ethnic Study of Atherosclerosis (MESA). Participants of the study underwent non-contrast chest CT, multimodal brain MRI, and cognitive testing. The study employed a deep learning algorithm developed at Johns Hopkins to assess baseline volumetric bone mineral density (vBMD) from the chest CT scans of 2,086 individuals. Ultimately, 715 participants with established vBMD were included for further MRI and cognitive assessment.

The analysis identified that lower baseline vBMD was linked to a more rapid decline in global cognitive function. Specifically, lower bone density was associated with accumulations of white matter hyperintensities in the corpus callosum—a region integral to executive functioning and memory—and a pronounced reduction in white matter fractional anisotropy within the anterior limb of the internal capsule.

Dr. Shadpour Demehri, professor of radiology and senior author of the study, underscored the significance of these findings. “This study is the first longitudinal secondary analysis linking baseline vertebral bone mineral density to changes in white matter structure, white matter hyperintensity progression, and cognition,” he stated. He emphasized that while the study's results show a correlation, they do not imply a direct causal relationship between bone density and dementia.

The researchers propose that both bone and brain degeneration may share metabolic drivers associated with aging, such as insulin resistance, dyslipidemia, and menopausal changes. Rather than suggesting that osteoporosis directly causes cognitive decline, the study posits a shared metabolic syndrome as a potential factor.

This research also highlights the utility of chest CT scans, often used for various health screenings, in opportunistically assessing bone density. Dr. Momtazmanesh remarked on the potential for these scans to offer valuable information on skeletal health—and indirectly, cognitive health—without requiring additional procedures. Furthermore, Dr. Demehri suggested that artificial intelligence could play a pivotal role in synthesizing diagnostic imaging data, enabling the identification of interconnected age-related pathologies that were traditionally studied separately.

This study opens the door for further examination of bone health as a marker for neurological decline, potentially leading to earlier intervention and management of shared risk factors.

For more detailed findings, the full study is accessible in the Radiology journal under the title, "Deep Learning-derived Bone Mineral Density and Longitudinal White Matter Microstructure and Cognitive Decline: Multi-Ethnic Study of Atherosclerosis."