口服最小模型法评估中青年及老年人的胰岛素敏感性和胰岛分泌功能及其影响因素

Evaluation of insulin sensitivity and pancreatic secretion function in young and elderly individuals using the oral minimal model method and its influencing factors

目的评估老年人胰岛素敏感性(IS)和胰岛β细胞分泌功能及其影响因素,并分析其与中青年的差异性。方法选取2018年12月至2021年6月于江苏省人民医院老年内分泌科的体检人群301例,既往无糖尿病病史,根据年龄分为老年组和中青年组,记录受试者个人史和疾病史;测量身高、体重、腰围、臀围,检测血脂、营养代谢指标;通过双能X线骨密度测量仪(DXA)测定体成分;采用口服最小模型(OMM)法得到胰岛素敏感性指数(ISI)、动态胰岛素分泌(Φd)、静态胰岛素分泌(Φs)、总胰岛素分泌(Φt)和处置指数(DI),并根据口服葡萄糖耐量实验结果分组,分析影响老年人和中青年IS和胰岛β细胞功能的因素及差异性。结果校正性别和体质指数(BMI)的偏相关分析结果显示,Φd、DI-Φd、DI-Φt均随增龄下降(r=-0.219、-0.210、-0.187,P=0.005、0.015、0.017),而ISI、Φs、Φt、DI-Φs与年龄无明显相关性。根据糖耐量结果分组后,虽然老年人和中青年各组之间的ISI差异无统计学意义(均P>0.05),但在校正ISI后,老年新发糖尿病人群的DI-Φd、DI-Φs、DI-Φt反而高于成年新发糖尿病人群。纳入年龄、高密度脂蛋白胆固醇(HDL-C)、全身肌肉总量、腰臀脂肪量比值(A/G)和脂肪量指数(FMI)等构建二元Logistic回归方程,结果显示,FMI均为老年组和中青年组ISI的危险因素(OR=2.324、1.773,P=0.032、0.005),A/G均为老年组和中青年组DI-Φd的危险因素(OR=69252.464、407.653,P=0.012、0.001)。除此之外,HDL-C为老年组ISI的保护因素(OR=0.024,P=0.012),而年龄的增长为老年人DI-Φs的危险因素(OR=1.454,P=0.039);全身肌肉总量和A/G为中青年组ISI的危险因素(OR=1.054、15.725,P=0.021、0.026),FMI为中青年组DI-Φs的危险因素(OR=1.826,P=0.035)。结论胰岛β细胞分泌功能随增龄减退,而ISI无增龄改变;影响老年人和中青年ISI、DI-Φd、DI-Φs的因素并不完全相同,提示针对不同年龄人群可能采用不同的生活方式干预更有利于保护ISI和胰岛β细胞功能。

Objective To evaluate insulin sensitivity(IS)and pancreaticβ-cell secretion function in the elderly,analyze the influencing factors,and compare these parameters with those observed in adults.Methods A total of 301 participants were selected from the health examination population at the Geriatrics Endocrinology Department of Jiangsu Provincial People's Hospital,all of whom had no history of diabetes,between December 2018 and June 2021.Participants were categorized into elderly and adult groups based on age.Personal and medical histories were recorded,and various measurements,including height,weight,waist circumference,hip circumference,blood lipids,and nutritional metabolic indicators,were obtained.Body composition was assessed using dual-emission X-ray absorptiometry(DXA).The oral minimal model(OMM)method was utilized to derive the insulin sensitivity index(ISI),dynamic insulin secretion(Φd),static insulin secretion(Φs),total insulin secretion(Φt),and disposition index(DI).Participants were grouped according to the results of oral glucose tolerance tests.Finally,the factors influencing IS and pancreaticβ-cell function were analyzed in both elderly and adult populations,as well as to identify any differences between the two groups.Results Following adjustments for gender and body mass index(BMI),partial correlation analysis indicated a decrease inΦd,DI-Φd,and DI-Φt with advancing age(r=-0.219,-0.210,-0.187;P=0.005,0.015,0.017).In contrast,ISI,Φs,Φt,and DI-Φs showed no significant correlation with age.Although ISI levels were comparable between the elderly and adult groups,individuals newly diagnosed with diabetes in the elderly cohort exhibited higher DI-Φd,DI-Φs,and DI-Φt compared to those in the adult group after ISI correction.When incorporating age,high-density lipoprotein cholesterol(HDL-C),total muscle mass,the android to gynoid ratio(A/G),and fat mass index(FMI)into a binary Logistic regression model,the findings underscored FMI as a common risk factor for both elderly and adult cohorts concerning the ISI(OR=2.324,1.773;P=0.032,0.005).The A/G ratio was identified as a risk factor for DI-Φd in both age groups(OR=69252.464,407.653;P=0.012,0.001).Furthermore,HDL-C was recognized as a protective factor for ISI(OR=0.024,P=0.012)in the elderly,while advancing age(OR=1.454,P=0.039)was found to be a risk factor for DI-Φs in this demographic.Total muscle mass and the A/G ratio were also acknowledged as risk factors for ISI(OR=1.054,15.725;P=0.021,0.026),with FMI serving as a risk factor for DI-Φs in the adult cohort(OR=1.826,P=0.035).Conclusions The secretion function of pancreaticβ-cells declines with age,whereas ISI remains unchanged.The factors affecting ISI,DI-Φd,and DI-Φs in elderly and adult populations show notable differences.This indicates that implementing targeted lifestyle interventions for distinct age groups may be more effective in preserving both ISI and pancreaticβ-cell function.