OBJECTIVE: To describe secondary failure of initial metformin therapy in patients who achieved initial HbA(1c) (A1C) <8% and to identify predictors of failure. RESEARCH DESIGN AND METHODS: We identified 1,288 patients who achieved A1C <8% within 1 year of initiating metformin as their first-ever antihyperglycemic drug. Subjects were followed until they added/switched antihyperglycemics, they terminated health plan membership, or 31 December 2004. We defined secondary failure using two separate but overlapping approaches: 1) addition/switch to another antihyperglycemic drug or 2) first A1C measurement >8.0% after at least 6 months on metformin. RESULTS: The best A1C achieved within 1 year of metformin initiation was the most powerful predictor of avoiding secondary failure. Approximately 50% of subjects whose best A1C was 7-7.9% added/switched antihyperglycemic drugs within 36 months, whereas it took >60 months for those in the 6-6.9% A1C category to reach a 50% failure rate. Those who achieved an A1C <6% did not reach a 50% rate of adding/switching drugs until 84 months. For the alternative secondary failure outcome, about half of those whose best A1C was 7.0-7.9% reached an A1C >8% within 24 months. Only approximately 25% of subjects in the 6-6.9% category failed by 48 months, and >80% of subjects in the <6% category remained below 8% through 60 months. CONCLUSIONS: Whether defined by adding/switching to another drug or by reaching an A1C of 8%, secondary failure is inversely associated with the reduction of A1C achieved within the 1st year of metformin monotherapy.
OBJECTIVE: To describe secondary failure of initial metformin therapy in patients who achieved initial HbA(1c) (A1C) <8% and to identify predictors of failure. RESEARCH DESIGN AND METHODS: We identified 1,288 patients who achieved A1C <8% within 1 year of initiating metformin as their first-ever antihyperglycemic drug. Subjects were followed until they added/switched antihyperglycemics, they terminated health plan membership, or 31 December 2004. We defined secondary failure using two separate but overlapping approaches: 1) addition/switch to another antihyperglycemic drug or 2) first A1C measurement >8.0% after at least 6 months on metformin. RESULTS: The best A1C achieved within 1 year of metformin initiation was the most powerful predictor of avoiding secondary failure. Approximately 50% of subjects whose best A1C was 7-7.9% added/switched antihyperglycemic drugs within 36 months, whereas it took >60 months for those in the 6-6.9% A1C category to reach a 50% failure rate. Those who achieved an A1C <6% did not reach a 50% rate of adding/switching drugs until 84 months. For the alternative secondary failure outcome, about half of those whose best A1C was 7.0-7.9% reached an A1C >8% within 24 months. Only approximately 25% of subjects in the 6-6.9% category failed by 48 months, and >80% of subjects in the <6% category remained below 8% through 60 months. CONCLUSIONS: Whether defined by adding/switching to another drug or by reaching an A1C of 8%, secondary failure is inversely associated with the reduction of A1C achieved within the 1st year of metformin monotherapy.
Authors: Darin E Olson; Ming Zhu; Qi Long; Diana Barb; Jeehea S Haw; Mary K Rhee; Arun V Mohan; Phyllis I Watson-Williams; Sandra L Jackson; Anne M Tomolo; Peter W F Wilson; K M Venkat Narayan; Joseph Lipscomb; Lawrence S Phillips Journal: J Gen Intern Med Date: 2015-01-22 Impact factor: 5.128
Authors: Adrianne C Feldstein; Gregory A Nichols; David H Smith; A Gabriela Rosales; Nancy Perrin Journal: J Gen Intern Med Date: 2008-06-28 Impact factor: 5.128
Authors: David C Ziemer; Paul Kolm; Jovonne K Foster; William S Weintraub; Viola Vaccarino; Mary K Rhee; Rincy M Varughese; Circe W Tsui; David D Koch; Jennifer G Twombly; K M Venkat Narayan; Lawrence S Phillips Journal: J Gen Intern Med Date: 2008-03-12 Impact factor: 5.128
Authors: L S Phillips; D C Ziemer; P Kolm; W S Weintraub; V Vaccarino; M K Rhee; R Chatterjee; K M V Narayan; D D Koch Journal: Diabetologia Date: 2009-06-26 Impact factor: 10.122
Authors: Itamar Raz; Matthew C Riddle; Julio Rosenstock; John B Buse; Silvio E Inzucchi; Philip D Home; Stefano Del Prato; Ele Ferrannini; Juliana C N Chan; Lawrence A Leiter; Derek Leroith; Ralph Defronzo; William T Cefalu Journal: Diabetes Care Date: 2013-06 Impact factor: 19.112