男性骨量减少者与骨质疏松者的体重指数与腰椎平均骨密度的相关性研究

On Correlation Between Body Mass Index and Lumbar Spine Average Bone Mineral Density:A Study in Male Patients with Osteopenia and Those with Osteoporosis

从2003年8月-2005年12月因骨关节疼痛在四川大学华西医院康复科就诊的男性患者中,选取40岁以上且无腰椎骨质增生,T值〈-1者为研究对象,共566例,年龄40-93岁,平均62.93±13.50岁。测定L2-4正位骨密度,记录其年龄、身高、体重、糖尿病患病情况、运动和吸烟习惯等基线资料,并计算体重指数。按T值大小分骨量减少组和骨质疏松组。结果显示：两组基线资料中,BMI及运动状况比较,差异有统计学意义（P〈0.05）,骨质疏松组的BMI大于骨量减少组,但参加运动者较少;多元线性回归分析表明：BMI每增加1 kg/m^2,腰椎平均BMD将下降0.003 g/cm^2（P=0.002）;年龄与腰椎平均BMD呈负相关（B=-0.001,P=0.035）;参加运动情况为正相关（P=0.000）;而吸烟情况对腰椎平均BMD的影响无统计学意义（P=0.837）。提示BMI增加,即脂肪含量增加,会引起骨量减少及骨质疏松患者腰椎平均BMD的下降。有研究报道只有通过增加肌肉含量提高BMI者,才能预防骨质疏松,因此我们认为日后研究BMI与BMD相关性时,需考虑研究对象的肌肉含量。

From among the patients who visited the Dept.of Rehabilitation of West China Hospital for arthalgia in the period from Aug.2003 to Dec.2005,we recruited 566 male patients who were over 40 years of age and did not have hyperostosis in the lumbar spine,and whose T scores were each less than-1.Their ages ranged from 40 to 93 years,and the average age was 62.93±13.50.The dual-energy X-ray absorptiometry from DMS Company in France was used to measure the bone density of the L2-4 anterior-posterior.The basic data about the subjects,containing the age,height,weight,diabetes mellitus,exercise and smoking or not,were recorded.Then the body mass index were calculated.In accordance to the T score,the subjects were separated into two groups： osteopenia group and osteoporosis group.In comparison of the basic data between groups,BMI of osteoporosis group was significantly higher than that of the osteopenia group,but the number of the subjects who exercised was smaller（P〈0.05）.Multiple linear regression analysis revealed that in the case BMI increased by 1 kg/m2,BMD significantly decreased by 0.003 g/cm^2（P=0.002）,and the age negatively correlated with BMD（B=-0.001,P=0.035）.＂Exercise or not＂ was positively related to BMD（B=0.028,P=0.000）.＂Smoking or not＂ and BMD were not significantly correlated（P=0.837）.In conclusion,increase of BMI,or we may say,increase of fat,would decrease the lumbar spine average BMD in the patients of osteoporosis or osteopenia.Some reports have pointed out that only by increasing BMI with increased amount of muscles,but not with increased amount of fat,would be beneficial to the prevention of osteoporosis.So we concluded that the muscle amount in the subjects should be taken into account when we probe into the relation between BMI and BMD.