Prevention of hip fractures by exposure to sunlight and pharmacotherapy in patients with Alzheimer's disease.
OBJECTIVE
Hypovitaminosis D and K due to malnutrition or sunlight deprivation, compensatory hyperparathyroidism, increased bone resorption, low bone mineral density (BMD), and an increased risk of falls may contribute to an increased risk of hip fractures in patients with Alzheimer's disease. The purpose of the present study was to clarify the efficacy of interventions against hip fractures in patients with Alzheimer's disease.


METHODS
With respect to randomized controlled trials (RCTs) regarding Alzheimer's disease and hip fractures, the literature was searched with PubMed.


RESULTS
Three RCTs were identified, and the relative risk (RR) and 95% confidence interval (CI) were calculated for individual RCTs. Exposure to sunlight with calcium supplementation, menatetrenone (vitamin K2) plus calcium and vitamin D supplementation, and risedronate plus calcium and vitamin D supplementation improved hypovitaminosis D and hyperparathyroidism, contributing to a reduction in bone resorption. Risedronate itself strongly decreased bone resorption. Menatetrenone also decreased the serum level of undercarboxylated osteocalcin. The three interventions increased metacarpal BMD and reduced the incidence of hip fractures. The respective RRs (95% CI) were 0.22 (0.049-0.999), 0.13 (0.031-0.554), and 0.26 (0.100- 0.690).


CONCLUSIONS
The present study clarified the efficacy of three interventions, including exposure to sunlight, menatetrenone, and risedronate with calcium and/or vitamin D supplementation against hip fractures in patients with Alzheimer's disease.
Iwamoto
Jun
J
Institute for Integrated Sports Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. jiwamoto@sc.itc.keio.ac.jp
Sato
Yoshihiro
Y
Tanaka
Kiyoshi
K
Takeda
Tsuyoshi
T
Matsumoto
Hideo
H
D000368:Aged; D000544:Alzheimer Disease / Q000150:complications* / Q000188:drug therapy* / Q000532:radiotherapy*; D015519:Bone Density / Q000187:drug effects*; D050071:Bone Density Conservation Agents / Q000627:therapeutic use*; D002118:Calcium / Q000627:therapeutic use; D003072:Cognition Disorders / Q000209:etiology; D019587:Dietary Supplements; D012968:Etidronic Acid / Q000031:analogs & derivatives* / Q000627:therapeutic use; D005260:Female; D006490:Hemostatics / Q000627:therapeutic use; D006620:Hip Fractures / Q000453:epidemiology / Q000517:prevention & control*; D006801:Humans; D008297:Male; D016032:Randomized Controlled Trials as Topic; D000068296:Risedronic Acid; D013472:Sunlight; D014807:Vitamin D / Q000627:therapeutic use; D024482:Vitamin K 2 / Q000031:analogs & derivatives / Q000627:therapeutic use
D050071:Bone Density Conservation Agents; D006490:Hemostatics; D024482:Vitamin K 2; D014807:Vitamin D; C030814:menatetrenone; D000068296:Risedronic Acid; D012968:Etidronic Acid; D002118:Calcium