RT Journal
A1 Esposito K, Bellastella G, Giugliano D
T1 WHen metformin fails in type 2 diabetes mellitus
JF Archives of Internal Medicine
JO Archives of Internal Medicine
YR 2011
FD February 28
VO 171
IS 4
SP 365
OP 369
DO 10.1001/archinternmed.2011.4
UL http://dx.doi.org/10.1001/archinternmed.2011.4
AB 
Type 2 diabetes mellitus is a complex and progressive disease that shows an apparently unstoppable increase worldwide. The last report on health in the United States in 2009 shows that 15% or more of the adult population 65 years and older is taking antidiabetic drugs, with an absolute increase of 6% compared with the years 1988 through 1994.1 Moreover, diabetes is the third cause of death for women and the fourth for men.2 Tight glycemic control, to maintain a hemoglobin A1c (HbA1c) concentration of 7% or lower, is recommended for all nonpregnant adults with diabetes to minimize the risk of long-term vascular complications.3 As a consequence, current diabetes guidelines4 suggest adjustment of therapy based on HbA1c level. The American Diabetes Association/European Association for Study of Diabetes (ADA/EASD) guidelines indicate metformin as starter pharmacological therapy in drug-naive patients with type 2 diabetes (step 1) and then insulin (basal) or a sulfonylurea when metformin fails (step 2).4 All other glucose level–lowering therapies are only recommended for selected clinical settings. In theory, the posttreatment HbA1c status (<7% vs ≥7%) should condition any future therapeutic choice; however, we cannot find any study that systematically assessed the proportion of patients with type 2 diabetes reaching the HbA1c target of 7% with antidiabetic drugs after metformin treatment failure.