The aim of the present study was to compare the absolute reduction in glycated haemoglobin (HbA1c) levels at 6 months after initiating second-line glucose-lowering therapy in patients with type 2 diabetes treated with metformin monotherapy in general practices. A total of 7009 patients were identified (Disease Analyser Germany: January 2004 to December 2014). The patients' mean ± standard deviation (s.d.) age was 63 ± 11 years, 55.5% were male and their mean ± s.d. HbA1c level was 8.0 ± 1.6%. The initiated second-line therapies included: dipeptidyl peptidase-4 (DPP-4) inhibitors (38.7%); sulphonylureas (36.3%); insulin (13.3%); glucagon-like peptide-1 receptor agonists (GLP-1RAs; 2.5%); thiazolidinediones (5%); and other agents (glinides, aldose-reductase inhibitors; 4.1%). The mean absolute HbA1c change from baseline was -0.9% (DPP-4 inhibitors, -0.9%; sulphonylureas, -0.9%; insulin, -1.1%; GLP-1RAs, -0.7%; thiazolidinediones, -0.9%; and other, -0.7%; all p < 0.001). Overall, 58% of patients reached the HbA1c target of <7% (DPP-4 inhibitors, 61.7%; sulphonylureas, 56.7%; insulin, 45.6%; GLP-1RAs, 62.2%; thiazolidinediones, 69.7%; and other, 57.5%). Compared with sulphonlyureas, DPP-4 inhibitors, GLP-1RAs and thiazolidinediones were associated with an increased odds of reaching HbA1c <7% [odds ratio (OR) 1.24, 95% confidence interval (CI) 1.09-1.40; OR 1.43, 95% CI 1.01-2.04; and OR 1.70, 95% CI 1.30-2.23, respectively], whereas insulin was related to a lower odds (0.66, 95% CI 0.55-0.78). In conclusion, in patients with type 2 diabetes very similar reductions in HbA1c after 6 months of second-line therapy were achieved regardless of the type of therapy.
Keywords: HbA1c; glucose-lowering drugs; glycaemic control; metformin; type 2 diabetes.
© 2016 John Wiley & Sons Ltd.