title: Safety and effectiveness of U-500 insulin therapy in patients with insulin-resistant type 2 diabetes mellitus.
abstract: OBJECTIVE
  To assess the safety and effectiveness of highly concentrated U-500 regular insulin in patients with insulin-resistant type 2 diabetes mellitus who were switched from U-100 insulin.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Outpatient diabetes management clinic.
  
  
  METHODS
  Twenty-one adults with poorly controlled type 2 diabetes and insulin resistance who were referred to the clinic between July 1, 2007, and June 30, 2008, and whose therapy was changed from large doses of U-100 insulin to U-500 insulin.
  
  
  RESULTS
  Demographic and clinical data were collected through a computerized medical record system. Insulin resistance was defined as a requirement of more than 200 units/day of insulin and more than 100 units/injection. The primary outcome was the change in hemoglobin A(1c) (A1C) after switching from any type of U-100 insulin to stabilization with U-500 highly concentrated regular insulin. Secondary outcomes were the changes in number of daily insulin injections, daily insulin dose, and body weight. With use of U-500 insulin, patients were able to achieve an average reduction in A1C of 1.7% (p<0.001). The mean number of daily injections decreased from 4.3 with U-100 insulin to 2.7 after using U-500 insulin (p<0.001), but changes in body weight after the change in insulin were not statistically significant (279.8 vs 279.2 lbs, p=0.429). No patient discontinued U-500 insulin during the study, and none experienced hypoglycemia severe enough to require the assistance of another individual.
  
  
  CONCLUSIONS
  In patients with insulin-resistant diabetes who have requirements of more than 200 units/day or 100 units/injection, use of U-500 regular insulin provided the same or better glucose control compared with U-100 insulin, with fewer daily injections and reduced injection volume. Although this drug represents an excellent treatment option, its safe use requires an experienced physician, a motivated and cooperative patient, and a dynamic diabetes management team.
authors.affiliation: Division of Endocrinology, Malcom Randall Veterans Administration Medical Center, Gainesville, Florida 32608, USA.
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Quinn
authors.forename: M Cecilia
authors.initials: MC
authors.lastname: Lansang
authors.forename: Deanna
authors.initials: D
authors.lastname: Mina
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000187:drug effects; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000503:physiopathology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007003:Hypoglycemia / Q000139:chemically induced / Q000453:epidemiology; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D007328:Insulin / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin