Association Of Body Fat Percentage With Time In Range During Short-term Insulin Pump Therapy In Type 2 Diabetes

Background and objectiveShort-term intensive insulin pump therapy,which can achieve the glycemic target earlier and shorten the time of glucotoxicity,is one of the standard interventions for type 2 diabetes mellitus(T2DM)patients with poor glycemic control.However,there were large individual variations,among which obesity was closely related to insulin resistance.And body fat quantity may be an important factor affecting glycemic control in T2DM.Thus,this study intends to investigate the association between body fat percentage and time in range(TIR)during short-term intensive insulin pump therapy in T2DM patients with poor glycemic control.MethodsA total of 85 T2DM patients were included in the present study.All participants were treated with continuous subcutaneous insulin infusion for 72 hours after their admission,combined with flash glucose monitoring(FGM).A total of 288 recorded values obtained during the first 72 hours of insulin pump therapy of each patient were selected for analysis.Then,we calculated the time in range(TIR),time above range(TAR),time below range(TBR)and other glycemic variability metrics during insulin pump therapy.Among them,TIR was considered to be the proportion of time that glucose concentration was in the target range,that is 3.9-10.0mmol/L.In addition,bioelectrical impedance analyzer was used to measure body composition.The cut-off point of body fat percentage was 25%for adult males and 30%for females.Overfat was defined as exceeding the above cut-off values.Then,the TIR,TAR,TBR,and glycemic variability parameters between normal fat group and overfat group were further compared.Besides,we divided the study participants into three groups according to TIR tertiles,so that the body fat percentage,waist circumference,BMI and other anthropometric indicators of patients with different TIR levels could be compared.Furthermore,we used a multiple linear regression analysis to evaluate the independent relationship between body fat percentage and TIR during insulin pump therapy.Finally,smoothing function analysis was also conducted to determine the correlation between body fat percentage and TIR,TAR,TBR,coefficient of variation(CV).And the threshold effect was further analyzed by two-piecewise linear regression model.ResultsIn overfat group,the TIR was significantly lower(P=0.004),whereas the TAR,72h mean blood glucose concentration and homeostasis model assessment 2-insulin resistance(HOMA2-IR)were higher than that of normal fat group during short-term intensive insulin pump therapy(All P<0.05).However,the T2DM patients in overfat group exhibited lower levels of TBR(P=0.003)and CV(P=0.033)when compared to the normal fat group.In addition,the study population were divided into three groups according to the TIR tertiles,that is,T1 group:TIR≤43.75%,T2 group:TIR 43.76-57.29%and T3 group:TIR≥57.30%.The proportion of patients with overfat was significantly different in the TIR tertiles groups.The proportion of overfat was 65.5%in T1 group,41.4%in the T2 group and 33.3%in the T3 group,respectively(P=0.041).The multiple linear regression analysis showed that body fat percentage was independently associated with TIR after adjusting for confounding factors,including gender,age,HbAlc,diabetes duration and BMI(β=-0.435,P=0.043).Finally,smoothing function analysis further showed that body fat percentage was negatively associated with TIR and TBR,while positively correlated with TAR after adjusting the above confounding factors(all P<0.05).However,body fat percentage exhibited a nonlinear relationship with CV.According to the two-piecewise linear regression model,the CV decreased with the increase of body fat percentage when the body fat percentage was lower than 34.4%(β1=-0.517,P=0.039).But when the body fat percentage was>34.4%,the above trend was not significant(β2=1.754,P=0.096).There was a significant difference between β1 and β2(P=0.030).ConclusionBody fat percentage can affect glycemic control during short-term intensive insulin pump therapy in patients with T2DM.Overfat patients exist higher glycemic levels but lower TIR.Furthermore,patients with higher body fat percentage have lower risk of hypoglycemia and glycemic variability than those with lower body fat percentage.Body fat percentage is negatively correlated with TIR in T2DM.