北京老年妇女膳食钙摄入水平与骨量关系

The association between calcium intake bone mass in Beijing older women

目的研究老年妇女在不同膳食钙摄入水平下骨密度变化情况。方法从北京市3个城区6个街道17个社区中随机选取60岁以上(60～86岁)的老年妇女445人作为研究对象。采用食物频率表调查过去一年的膳食摄入,用双能X线吸收仪(DXA)测定其全身、股骨和腰椎骨密度。结果我国健康老年妇女不同部位的骨量、骨质疏松的发生率均不同,大转子发生骨质疏松的比例最高,达到19.4%。膳食钙摄入大于1000mg/d的研究对象的髋骨BMD和大转子BMD分别比钙摄入量小于1000mg/d的人高3.4%和4.9%(P<0.05);而大转子BMD诊断为骨质疏松的比例显著下降到12.7%(P<0.05),为"骨量正常"的比例显著增加。未观察到不同膳食钙摄入水平对全身和腰椎骨量的显著影响。结论膳食钙摄入对不同部分的效果不同,充分的膳食钙摄入有利于改善髋骨骨量。

Objective To observe the association between dietary calcium intake and bone mass in Beijing old postmenopausal women. Methods A total of 445 community-dwelling elderly women over 60 years（60 to 86 years old） were selected randomly from 17 communities of 6 blocks in 3 districts in Beijing. Their dietary intake were collected by food frequency questionnaires, and bone mineral density （BMD） at lumber spine, hips,and total body were measured by DXA（Norland XR-46,America）. Results The bone mass and the rate of osteoporosis varied in different position,with highest at trochanter as 19.4%. The BMD at hips and trochanter in subjects with dietary calcium intake more than 1000 mg/d were 3.4% and 4.9% higher than those in subjects with lower calcium intake （ P 〈 0.05 ） ; their prevalence of osteoporosis at trochanter decreased to 12.7% （P 〈 0. 05 ） ,with more normal bone mass at this position. No significant effect of calcium intake were observed on bone mass of total body or lumber spine. Conclusion Dietary calcium intake has different effect on variance position. More dietary calcium intake would benefit bone mass at hips.