Reasonable Application Of Continuous Subcutaneous Insulin Infusion In Elderly Patients With Type 2 Diabetes Mellitus

ObjectivesTo explore the application and optimization of continuous subcutaneous insulin infusion(CSII) in elderly patients with type 2 diabetes mellitus by analyzing the factors related to its effects and insulin dosage.To evaluate the effect of acute-stress and insulin category in the use of CSII in elderly patients with type 2 diabetes mellitus.MethodsA total of 200 patients with poorly-controlled type 2 diabetes in hospital were divided into two groups,group A(age＜60years,62 cases) and group B(age≥60years,118 cases).Group B were sub-divided into group B1(patients with acute-stress condition,53 cases) and group B2 (patients without acute-stress condition,65 cases).And all of the elderly patients were randomized to group BⅠ(n=61,treated with insulin Aspart) or group BⅡ(n=57,treated with Novolin R).All patients were treated with CSII to achieve target glycaemic control.The total efficacy of CSII were evaluated by blood glucose level,insulin dosage,time needed to control abnormal blood glucose,fluctuations of glucose and incidence of hypoglycaemia during the treatment.Difference of the use of CSII between these groups was analysed.Results1.Group A and Group B The time needed to control abnormal blood glucose shown no significant difference between group A and group B[(7.6±3.25)d vs(7.1±3.18)d,p＞0.05].While the insulin dose on the day achieving good glycemia control in group B was lower than that in group A[(0.63±0.22)u·kg^-1·d^-1 vs(0.72±0.21)u·kg^-1·d^-1,p＞0.05],the daily adminstration of premeal supplementary dose of insulin nearly occupied 60%in group B,while it occupied about 50%in groupA.The daily adminstration of basal insulin dose[(17.88±7.80)u vs (23.20±9.16)u],basal rate at night[20:00-02:00(0.59±0.34)u/h vs (0.85±0.38)u/h,02:00-08:00(0.73±0.34)u/h vs(1.02±0.48)u/h]were significantly lower in group B than those in group A(p＜0.01 for all),The basal insulin dosage at night in group B was about 70%of that in group A. The incidence of hypoglycemia was significantly higher in group B(0.15person-time/d vs 0.12 person-time/d,p＜0.05).There was no significant difference in the fluctuation of blood glucose between the two groups.2.Group B1 and Group B2 The time needed to achieve target glycaemic control in group B1 was much longer than that in group B2 [(9.8±3.1)days vs(5.8±2.0)days,p＜0.01].There was no significant difference in daily insulin dosage on the day achieving good glycemia control between the two groups.The frequency of hypoglycemic episodes was significantly higher in group B1 than that in group B2(0.19 person-time/d vs 0.12 person-time/d,p＜0.01).There was no significant difference in the fluctuation of blood glucose during the treatment between the two groups.3.Group BⅠand Group BⅡThe time for good glycemia control was shorter in group BⅠthan that in group BⅡ[(6.0±2.8)d vs (7.6±3.7)d,p＜0.05],mean of three postprandial blood glucose were significantly lower in group BⅠthan that in group BⅡ[(8.0±0.9)mmol/L vs(8.5±0.8)mmol/L,p＜0.05]with lower proportion of bolus before meal to daily total insulin dosage[(54.9±10.2)%vs(60.0±8.5)%,p＜0.01].The incidence of hypoglycemia was significantly higher in group BⅡthan that in group BⅠ(0.18 person-time/d vs 0.13 person-time/d,p＜0.01),the standard deviation of blood glucose(SDBG),which reflects the glycemic excursion was significantly lower in groupBⅠthan in group BⅡ[(3.0±1.0)vs(3.8±1.3),p＜0.05].There were no significant differences in basal or bolus insulin dosages on the day achieving target glycemia control between the two groups.4.Multiple stepwise regression analysis The days needed for achieving good control of blood glucose by CSII in group B was positively correlated with complications of acute stress(r=0.628,p=0.000), HbAlc level(r=0.190,p=0.010),duration of diabetes mellitus(r=0.139, p=0.042).The insulin dosage on the day achieving good glycemia control was positively correlated with the mean of postprandial blood glucose before the treatment(r=0.364,p=0.000),duration of diabetes mellitus (r=0.214,p=0.000),and HbAlc level(r=0.188,p=0.027),while it was negatively correlated with body weight level(r=-0.223,p=0.006) in group B.The days needed for achieving good control of blood glucose in group A was positively correlated with complications of acute stress(r=0.389, p=0.001).The insulin dosage on the day achieving good glycemia control was positively correlated with the mean of postprandial blood glucose before the treatment(r=0.565,p=0.000),complications of acute stress (r=0.435,p=0.001),while it was negatively correlated with body weight index(r=-0.270,p=0.011) in groupA.To sum up,the days needed for achieving good glucose control was most positively correlated with complications of acute stress and the insulin dosage on the day achieving good glycemia control was most positively correlated with the mean of postprandial blood glucose level before the treatment in the two groups.ConclusionsThe following applications of continuous subcutaneous insulin infusion is more reasonable in elderly patients with type 2 diabetes mellitus:1.The bolus insulin dosage occupies 60%of daily total insulin dosage while the basal dosage occupies 40%.The basal rate at night is much less in elderly patients,it is about 70%of that in general adult patients.2.Insulin Aspart provides a more effective and safe control of hyperglycemia than regular human insulin(Novolin R).3.Complications of acute stress does not affect the insulin dosage on the day achieving good glycemia control.