title: Weight gain and insulin requirement in type 2 diabetic patients during the first year after initiating insulin therapy dependent on baseline BMI.
abstract: OBJECTIVE
  The aim of this study was to determine differences, if any, in weight gain and increased insulin requirements in insulin-treated type 2 diabetic patients with a normal and an elevated body mass index (BMI).
  
  
  METHODS
  A total of 192 patients with newly insulinized type 2 diabetes were included in the study. The patients were divided into three groups: those with BMI <26 (n = 102), BMI 26-30 (n = 50) and those with BMI >30 (n = 40). At the beginning of insulin therapy and 12 months later, we compared HbA1c, BMI and required insulin doses in each group and evaluated weight gain and the increase in insulin requirement during the observation period. Moreover, we investigated the influence of additional metformin therapy on weight gain and insulin requirement.
  
  
  RESULTS
  Body weight increased in the group with normal BMI from 68.8 +/- 9.2 to 70.8 +/- 9.4 kg (+2.9%) and in the other groups from 79.0 +/- 9.3 to 81.2 +/- 8.4 (+2.8%) and from 96.2 +/- 11.2 to 99.1 +/- 16.5 kg (+3.0%) respectively. The differences between the groups were not significant. The insulin requirement increased by 22% in the normal-weighted group and by 23% in both groups with overweight. The reduction in mean HbA1c was similar in the three groups (22, 18 and 22%). Under additional metformin therapy, the increment of insulin requirement of all patients (n = 40) was significantly lower (11 vs. 26%, p < 0.01), and there was no significant difference between the groups with different BMIs. During the same period, the gain in body weight and the decrease of HbA1c were not significantly different in the patients with and without metformin independent on the BMI.
  
  
  CONCLUSIONS
  The risk for weight gain and increase in insulin requirement is similar in insulin-treated type 2 diabetic patients with normal and elevated BMI. Additional metformin therapy reduces insulin requirement in patients with and without overweight.
authors.affiliation: Second Department of Medicine, Section Diabetes, General Hospital Linz, Linz, Austria. georg.biesenbach@akh.linz.at
authors.forename: G
authors.initials: G
authors.lastname: Biesenbach
authors.forename: A
authors.initials: A
authors.lastname: Raml
authors.forename: N
authors.initials: N
authors.lastname: Alsaraji
mesh_terms: D000368:Aged; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage* / Q000494:pharmacology; D007328:Insulin / Q000008:administration & dosage* / Q000494:pharmacology; D008297:Male; D008687:Metformin / Q000008:administration & dosage / Q000494:pharmacology; D008875:Middle Aged; D012189:Retrospective Studies; D015430:Weight Gain / Q000187:drug effects*
chemical_list: D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin; D008687:Metformin