Affiliations: [a] Department of Physical Therapy and Rehabilitation Sciences, University of Kansas School of Allied Health, Kansas City, KS, USA | [b] Department of Neurology, University of Kansas School of Medicine, Kansas City, KS, USA | [c] Hoglund Brain Imaging Center, University of Kansas Medical Center, Kansas City, KS, USA
Correspondence:
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Address for correspondence: Jeffrey M. Burns, MD, University of Kansas School of Medicine, Department of Neurology, MSN 1065, 2100 West 36th Avenue, Suite 110, Kansas City, KS 66160, USA. Tel.: +1 913 588 0555; Fax: +1 913 945 5035; E-mail: jburns2@kumc.edu.
Abstract: Studies suggest a link between bone loss and Alzheimer's disease. To examine bone mineral density (BMD) in early Alzheimer's disease (AD) and its relationship to brain structure and cognition, we evaluated 71 patients with early stage AD (Clinical Dementia Rating (CDR) 0.5 and 1) and 69 non-demented elderly control participants (CDR 0). Measures included whole body BMD by dual energy x-ray absorptiometry (DXA) and normalized whole brain volumes computed from structural MRI scans. Cognition was assessed with a standard neuropsychological test battery. Mean BMD was lower in the early AD group (1.11 ± 0.13) compared to the non-demented control group (1.16 ± 0.12, p = 0.02), independent of age, gender, habitual physical activity, smoking, depression, estrogen replacement, and apolipoprotein E4 carrier status. In the early AD group, BMD was related to whole brain volume (b = 0.18, p = 0.03). BMD was also associated with cognitive performance, primarily in tests of memory (logical memory [b = 0.15, p = 0.04], delayed logical memory [b = 0.16, p = 0.02], and the selective reminding task – free recall [b = 0.18, p = 0.009]). BMD is reduced in the earliest clinical stages of AD and associated with brain atrophy and memory decline, suggesting that central mechanisms may contribute to bone loss in early AD.
Keywords: Alzheimer's disease, bone mineral density, brain atrophy, hypothalamus, memory
