Lower Bone Density Associated With Cognitive Decline and Age-Related Brain Damage: Study - Video

Lower bone mineral density in the spine may be associated with faster cognitive decline and worsening age-related changes in the brain's white matter, according to a new study published in Radiology.

Researchers from Johns Hopkins University analysed data from the Multi-Ethnic Study of Atherosclerosis, combining chest CT scans, brain MRI results and cognitive testing. They used a deep-learning algorithm to measure thoracic vertebral volumetric bone mineral density from non-contrast chest CT scans.

The analysis included 715 participants with available bone-density measurements, brain MRI and cognitive assessments. Long-term MRI data on white matter changes were available for more than 400 participants.

The researchers found that lower baseline vertebral bone mineral density was associated with a faster decline in overall cognitive function. Lower bone density was also linked to greater accumulation of white matter hyperintensities in the corpus callosum, a brain structure involved in communication between the brain’s hemispheres and functions including attention, working memory and executive function.

In addition, people with lower bone mineral density showed a steeper decline in fractional anisotropy in the anterior limb of the internal capsule. Fractional anisotropy reflects the organisation and integrity of white matter fibres, with reductions associated with microstructural brain changes and cognitive decline.

Researchers stressed that the findings do not show that osteoporosis or low bone density causes dementia. Instead, the relationship may reflect shared biological processes that affect both bone and brain health during ageing. Possible common factors include insulin resistance, abnormal blood lipid levels and hormonal changes associated with menopause.

However, further research is needed to determine whether low bone density can reliably identify people at higher risk of cognitive decline and whether addressing shared risk factors could influence both skeletal and brain health.

REFERENCE: Shadpour Demehri, et al.; Deep Learning-derived Bone Mineral Density and Longitudinal White Matter Microstructure and Cognitive Decline: Multi-Ethnic Study of Atherosclerosis; Radiology; https://pubs.rsna.org/journal/radiology