Fang Aiping, Li Keji, Guo Meihan, He Jingjing, Li He, Shen Xin, Song Jie
Department of Nutrition and Food Hygiene, School of Public Health, Peking University, Beijing, China.
J Bone Miner Res. 2016 Nov;31(11):2016-2023. doi: 10.1002/jbmr.2874. Epub 2016 Jun 9.
The aim of this longitudinal study was to investigate long-term associations between low dietary calcium intake and fracture risk in older adults with plant-based diet. Data of self-reported first fracture events of any type from 6210 Chinese men and women, aged 50 years or older and free from fracture at baseline, in a subcohort based on the China Health and Nutrition Survey (CHNS), were analyzed. Diet was repeatedly assessed by a combination of three consecutive 24-hour individual dietary recalls and a weighing and measuring of household food inventory in each round. The older men and women habitually ingested mean (SD) of 415 (147) mg/d and 373 (140) mg/d of calcium from plant-based diet, respectively. During a median follow-up of 7.0 years, 127 men (4.34%) and 232 women (7.06%) experienced first fracture events. The crude rates were 4.88, 2.55, and 6.83 per 1000 person-years at risk for men, and 6.72, 7.10, and 11.0 per 1000 person-years at risk for women in the lowest, third, and highest quintile of dietary calcium intake. In nonlinear regressions, an increased risk of fracture was associated with dietary calcium intake more than 778 mg/d (multivariable adjusted hazard ratio [HR] 2.10, 95% confidence interval [CI] 1.00-4.41) or lower than 275 mg/d (1.74, 95% CI 1.00-3.01) for men and more than 651 mg/d for women (1.54, 95% CI 1.00-2.38). A nonsignificant trend of increase in fracture risk was found below 248 mg/d (1.00, 95% CI 0.67-1.50) in women using restricted cubic spline Cox regression. A relatively low fracture risk is observed in men with dietary calcium intakes of 275 to 780 mg/d and in women with intakes of 250 to 650 mg/d, and higher intakes may have no further benefit for fracture prevention. The patterns of dietary calcium with fracture risk are U-shaped in men and possibly in women. © 2016 American Society for Bone and Mineral Research.
这项纵向研究的目的是调查以植物性饮食为主的老年人饮食中钙摄入量低与骨折风险之间的长期关联。对基于中国健康与营养调查（CHNS）的一个亚队列中6210名年龄在50岁及以上且基线时无骨折的中国男性和女性自我报告的任何类型首次骨折事件的数据进行了分析。通过连续三次24小时个人饮食回忆以及每次对家庭食物库存进行称重和测量相结合的方式，反复评估饮食情况。这些老年男性和女性从植物性饮食中习惯性摄入的钙平均（标准差）分别为415（147）mg/天和373（140）mg/天。在中位随访7.0年期间，127名男性（4.34%）和232名女性（7.06%）经历了首次骨折事件。在饮食钙摄入量最低、第三和最高五分位数组中，男性每1000人年的粗发病率分别为4.88、2.55和6.83，女性分别为6.72、7.10和11.0。在非线性回归中，男性饮食钙摄入量超过778 mg/天（多变量调整风险比[HR] 2.10，95%置信区间[CI] 1.00 - 4.41）或低于275 mg/天（1.74，95% CI 1.00 - 3.01），以及女性饮食钙摄入量超过651 mg/天（1.54，95% CI 1.00 - 2.38）时，骨折风险增加。在女性中，使用受限立方样条Cox回归发现在低于248 mg/天（1.00，95% CI 0.67 - 1.50）时骨折风险有不显著的增加趋势。饮食钙摄入量在275至780 mg/天的男性和250至650 mg/天的女性中观察到相对较低的骨折风险，更高的摄入量可能对预防骨折没有进一步益处。男性以及可能女性中，饮食钙与骨折风险的模式呈U形。© 2016美国骨与矿物质研究学会
