Chalhoub Didier, Marques Elisa, Meirelles Osorio, Semba Richard D, Ferrucci Luigi, Satterfield Suzanne, Nevitt Michael, Cauley Jane A, Harris Tamara
Intramural Research Program, Laboratory of Epidemiology and Population Sciences, National Institute on Aging, National Institutes of Health, Bethesda, Maryland.
Department of Ophthalmology, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
J Am Geriatr Soc. 2016 Dec;64(12):e304-e308. doi: 10.1111/jgs.14661. Epub 2016 Dec 2.
Klotho deficiency has been previously linked to aging-like phenotypes such as osteoporosis, cognitive impairment, and sarcopenia. Low serum klotho was shown to be related to grip strength and disability. Nonetheless, no previous study has explored the association between serum klotho and fractures. The purpose of this report is to examine the relationship of serum klotho with bone mineral density (BMD) loss and fractures in older adults.
The Health, Aging, and Body Composition (Health ABC) Study is a longitudinal cohort study of 3,075 community-dwelling older adults.
US clinical centers.
Two thousand seven hundred and seventy six well-functioning black and white adults aged 70 to 79 years with serum klotho measurements were followed up for a median of 5 years.
Percent annualized BMD change and fracture risk were compared across klotho quartiles. A Poisson distribution was used to calculate age-adjusted fracture incidence rates, and Cox proportional hazards models for multivariable-adjusted hazard ratios.
The annualized percent changes in hip, femoral neck, and vertebral BMD were similar across klotho quartiles. Participants experienced 507 nonspine fractures, 203 hip fractures, and 135 vertebral fractures. The Incidence rate (IR) of nonspine fractures was 17 per 1,000 person-years. The most frequent site was hip (IR = 6 per 1,000 person-years) and the IR of vertebral fractures was 3 per 1,000 person-years. There was no association between the lowest quartile of plasma klotho and nonspine (hazard ratio (HR) = 1.19, 95% confidence interval (CI) = 0.86-1.65), hip (HR = 1.34, 95% CI = 0.79-2.27), or vertebral fractures (HR = 1.17, 95% CI = 0.65-2.11).
Although klotho gene is a susceptible gene for reduced BMD, klotho blood concentration does not appear to be a predictor of bone loss or fracture risk in well-functioning older adults.
此前已发现，klotho缺乏与骨质疏松症、认知障碍和肌肉减少症等衰老样表型有关。低血清klotho与握力和残疾有关。然而，此前尚无研究探讨血清klotho与骨折之间的关联。本报告旨在研究老年人血清klotho与骨密度（BMD）丢失及骨折之间的关系。
健康、衰老与身体成分（Health ABC）研究是一项针对3075名社区居住老年人的纵向队列研究。
美国临床中心。
对2776名70至79岁功能良好的黑人和白人成年人进行了血清klotho测量，并对他们进行了为期5年的随访。
比较klotho四分位数之间的年化BMD变化百分比和骨折风险。采用泊松分布计算年龄调整后的骨折发病率，并使用Cox比例风险模型计算多变量调整后的风险比。
klotho四分位数之间，髋部、股骨颈和椎体BMD的年化变化百分比相似。参与者发生了507例非脊柱骨折、203例髋部骨折和135例椎体骨折。非脊柱骨折的发病率（IR）为每1000人年17例。最常见的部位是髋部（IR = 每1000人年6例），椎体骨折的IR为每1000人年3例。血浆klotho最低四分位数与非脊柱骨折（风险比（HR） = 1.19，95%置信区间（CI） = 0.86 - 1.65）、髋部骨折（HR = 1.34，95% CI = 0.79 - 2.27）或椎体骨折（HR = 1.17，95% CI = 0.65 - 2.11）之间无关联。
尽管klotho基因是骨密度降低的易感基因，但在功能良好的老年人中，klotho血液浓度似乎不是骨质流失或骨折风险的预测指标。
