Bone Loss Mirrors Cognitive Decline?
The observation that osteoporosis may be associated with poor cognitive function, especially in the elderly population, suggests a link between two of the most common diseases that can affect women with age.
Estrogen deficiency may explain this association, although it is possible that other primary mechanisms may be at work.
A study involving 8,333 community-dwelling women (all 65 years of age or older) evaluated the potential association between bone mineral density (BMD) and cognitive decline. Calcaneal and hip BMD were measured at baseline and at followup 4-6 years later, and vertebral fractures were documented radiologically at year six. Women were also monitored for cognitive changes by way of several questionnaires administered at baseline and at followup (modified mental status exam, Trails B and Digit Symbol exam).
Women with low baseline BMD had up to 8% worse cognitive scores at baseline and up to 6% worse scores at followup than women with higher BMD at baseline. Women with vertebral fractures also revealed lower cognitive test scores and greater risk of cognitive decline than women without fractures.
These findings provide evidence of the possible link between osteoporosis and poor cognitive function, as measured specifically by bone mineral density levels and loss over time. The authors note that "further understanding of this association may be important for new treatment and prevention directions."
Yaffe K, Browner W, Cauley J, et al. Association between bone mineral density and cognitive decline in older women. Journal of the American Geriatric Society
, 1999:47, pp1176-1182.