The IMPROVE study--a multinational, observational study in type 2 diabetes: data from the Polish cohort.

INTRODUCTION: Observational studies are valuable tools for assessing the applicability of results from randomised controlled trials to broader patient populations. They are especially important in chronic diseases such as diabetes, as they can provide a comprehensive picture of the safety and effectiveness of a particular therapy across cultures and phenotypes.
MATERIAL AND METHODS: Patients with type 2 diabetes who required insulin and whose physician had decided to initiate biphasic insulin aspart 30 (BIAsp 30) were eligible. A total of 4117 type 2 diabetic patients were recruited to the study in Poland, and 809 primary and secondary care physicians were involved. The aim of this study was to assess the safety and effectiveness of BIAsp 30 treatment in type 2 diabetes in routine clinical practice.
RESULTS: Baseline glycaemic control was poor in the Polish cohort enrolled in the IMPROVE(TM) study, with a mean HbA(1c) value of 9.0 +/- 1.7%. A very high proportion of patients were thus at risk of macrovascular and microvascular complications. A twice-daily regimen for the start of BIAsp 30 therapy was the most common choice, including 72.2% of patients at baseline. HbA(1c) was significantly reduced by 1.66% for the total cohort and by 3.07% and 1.55% in the pre-study no-therapy or oral antidiabetic drug group respectively (p < 0.001). The rates (episodes per subject year) of overall major hypoglycaemia were 0.012 and 0.12 at follow-up and final visits respectively. For minor hypoglycaemia rates of 5.12 per subject per year at follow-up visit and 4.54 episodes per subject per year at final visit were recorded.
CONCLUSIONS: BIAsp 30 appears to be an effective and flexible treatment approach and can be safely intensified to achieve glycaemic control in a majority of patients with type 2 diabetes.