title: Risk factors for hip fracture among elderly patients with Alzheimer's disease.
abstract: Incidence of hip fracture among patients with Alzheimer's disease (AD), especially in elderly patients, is high. To analyze risk factors of hip fracture, we prospectively studied a cohort of elderly female patients with AD. Subjects studied were 225 female patients with AD, and the average age was 76 years old. At baseline, we recorded body mass index (BMI), a score of Mini-Mental State Examination (MMSE) and bone mineral density (BMD), and measured serum concentrations of ionized calcium, intact parathyroid hormone (PTH), pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP), intact bone Gla protein (BGP), 25-hydroxyvitamin (25-OHD) and 1, 25-dihydroxyvitamin D (1, 25-[OH]2D). The patients were followed for 2 years. During the 2-year study, hip fractures occurred in 29 patients. We compared baseline variables between the 29 patients with and 176 patients without hip fracture. AD patients with lower BMD, low concentrations of serum ionized calcium and 25-OHD (mean 3.0 ng/ml) with compensatory hyperparathyroidism were found to have an increased risk of hip fracture. Also, concentrations of serum ICTP and BGP were higher in the fracture group than in the nonfracture group. Elderly female AD patients with low BMD and serum 25-OHD concentrations <5 ng/ml with secondary hyperparathyroidism have a high risk of hip fracture, and the risk may be reduced by vitamin D supplementation.
authors.affiliation: Department of Neurology, Mitate Hospital, 3237 Yugeta, Tagawa 826-0041, Japan. y-sato@ktarn.or.jp
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Sato
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Kanoko
authors.forename: Kei
authors.initials: K
authors.lastname: Satoh
authors.forename: Jun
authors.initials: J
authors.lastname: Iwamoto
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood / Q000150:complications*; D015992:Body Mass Index; D015519:Bone Density / Q000502:physiology; D002118:Calcium / Q000097:blood; D024042:Collagen Type I; D003710:Demography; D005260:Female; D005500:Follow-Up Studies; D006620:Hip Fractures / Q000097:blood / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D008609:Mental Status Schedule; D015675:Osteocalcin / Q000097:blood; D010281:Parathyroid Hormone / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D010455:Peptides; D011347:Procollagen / Q000097:blood; D011446:Prospective Studies; D012307:Risk Factors; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D024042:Collagen Type I; D010281:Parathyroid Hormone; D010446:Peptide Fragments; D010455:Peptides; D011347:Procollagen; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin; D014807:Vitamin D; C097949:1,25-dihydroxyvitamin D; C104450:25-hydroxyvitamin D; D002118:Calcium