早发2型糖尿病骨密度、骨代谢变化及影响因素分析

  目的  研究早发2型糖尿病(T2DM)骨密度、骨代谢水平改变并探讨其影响因素。  方法  选取2018年1月—2021年12月在上海交通大学医学院附属新华医院内分泌科住院的初诊年龄≤40岁的2型糖尿病患者201例为早发组，另以本院与早发组年龄、性别相匹配的非糖尿病患者107例为对照组。比较2组一般临床资料及腰椎L_1~4平均骨密度(BMD)、骨代谢水平差异。  结果  (1)校正BMI后，早发组与对照组BMD比较差异无统计学意义(F=1.004，P>0.05)，早发组1型原胶原氨基端前肽(P1NP)、骨钙素、25(OH)D₃、甲状旁腺激素均低于对照组(t=3.941、6.556、7.123、4.620，均P＜0.05)，2组1型胶原羧基端肽β特殊序列(β-CTX)比较差异无统计学意义(t=1.684，P>0.05)。(2)影响因素分析结果显示，BMD与年龄呈独立负相关关系(95% CI:-0.007~-0.001，P=0.012)，与BMI(95% CI:0.004~0.014，P=0.001)、糖化血红蛋白(95% CI:0.002~0.021，P=0.014)呈独立正相关关系；β-CTX与年龄(95% CI:-0.013~-0.003，P=0.001)、TC(95% CI:-0.079~-0.015，P=0.004)呈独立负相关关系，女性(95% CI:-0.177~-0.020，P=0.014)是β-CTX降低的独立危险因素；P1NP与年龄(95% CI:-0.831~-0.137，P=0.007)、空腹血糖(95% CI:-1.815~-0.333，P=0.005)、TG(95% CI:-0.635~-0.508，P=0.004)呈独立负相关关系。  结论  早发2型糖尿病患者的骨密度与非糖尿病人群相比未见明显差异，但骨形成标志物降低，年龄、性别、BMI、血糖、血脂水平是其骨密度、骨代谢水平改变的独立影响因素。 

Changes in bone mineral density,bone metabolism and its influencing factors in early-onset type 2 diabetes mellitus

  Objective  To analyse the changes in bone mineral density, bone metabolism and its influencing factors in early-onset type 2 diabetes mellitus (T2DM).  Methods  We performed a retrospective analysis of 201 patients with T2DM who were diagnosed with diabetes aged ≤ 40 years old in the Department of Endocrinology, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine from January 2018 to December 2021. These subjects were classified as the early-onset group. In addition, we selected 107 non-diabetic patients matched with the early-onset group with regard to age and sex ratio as the control group. The general clinical data, biochemical indexes, mean bone mineral density (BMD) of lumbar spine L_1-4 and bone metabolism markers were compared between the two groups.  Results  (1) After correcting the BMI, no statistically significant difference in BMD was observed between the early-onset group and control group (F=1.004, P>0.05). The levels of type Ⅰ procollagen amino-terminal peptide, osteocalcin, 25(OH)D₃ and parathyroid hormone of the early-onset group were lower than those in the control group (t=3.941, 6.556, 7.123, 4.620, all P < 0.05), whereas no significant difference in β-carboxyl terminal peptide (β-CTX) was found between the two groups (t=1.684, P>0.05). (2) Correlation analysis results showed that BMD was independently and negatively correlated with age (95% CI: -0.007 to -0.001, P=0.012) but was independently and positively correlated with BMI (95% CI: 0.004 to 0.014, P=0.001) and HbA1c (95% CI: 0.002 to 0.021, P=0.014). β-CTX was independently and negatively correlated with age (95% CI: -0.013 to -0.003, P=0.001) and TC (95% CI: -0.079 to -0.015, P=0.004). In addition, the female gender was an independent risk factor for decreased β-CTX (95% CI: -0.177 to -0.020, P=0.014). P1NP was independently and negatively correlated with age (95% CI: -0.831 to -0.137, P=0.007), FPG (95% CI: -1.815 to -0.333, P=0.005) and TG (95% CI: -0.635 to -0.508, P=0.004).  Conclusion  There is no significant difference in BMD amongst patients with early-onset type 2 diabetes compared with non-diabetic people, but the markers of bone formation decrease. The age, gender, BMI, blood glucose and blood lipid levels are independent influencing factors of changes in BMD and bone metabolism in patients.