The Relation of Changes in Prescribing Patterns of Anti-diabetic Drugs and HbA1c Levels Among Patients with Type 2 Diabetes Mellitus: Systematic Analysis of Studies From the the Past 20 Years in Turkey

ABSTRACT

Background: The level of glycemic control is considered to be too low among patients with type 2 diabetes mellitus (DM) in Turkey. Despite availability of several anti-diabetic treatment alternatives, substantial amount of diabetic patients are at increased risk of diabetes-related macrovascular as well as microvascular complications.
Objective: To evaluate glycemic control, disease-related complications and treatment patterns in patients with type 2 DM in Turkey and the effect of novel anti-diabetic therapeutics, especially, insulin analogues in on these parameters.
Material and Method: In this systematic review, we included studies on type 2 diabetes mellitus patients published in national and international journals and the abstracts presented in the congresses held in Turkey from 1990 to 2010. The common property of these publications was the inclusion of study population ofadult type 2 diabetes mellitus patients with available data regarding HbA1c values, frequency of diabetes-related complications, and treatments. Of 136 publications screened, a total of 92 were considered eligible to be analysed and were included in the present systematic review.
Results and Conclusion: The mean±SD HbA1c level was determined to be 8.34%±0.90% in studies providing data on HbA1c level (64 publications with 16.378 patients) This value was 8.90% in publications of 1990-1999 while decreased to 8.28% in 2000-2008. The rates of patients with appropriate glycemic control (HbA1c level of <7% as recommended in American Diabetes Association (ADA) guidelines or ≤6.5% as recommended in American Association of Clinical Endocrinologists (AACE) guidelines) were 30.1% and 20.7%, respectively. There was a significant increase in the rate of of patients having appropriate glycemic control within the period of 2000-2008 compared with the 1990-1999. In the same period, the regression was also evident for the rate of patients with retinopathy amongst DM related-complications from 48.4% to 32.9%. Most of patients (60.5±10.8%) included in the analysis were identified to receive ongoing oral anti-diabetic (OAD) treatment followed by insulin (17.1%±12.5%), diet (14.3%±14.4%) and OAD+insulin (9.2%±10.5%). In conclusion, analysis of a total of 26.898 patients with type 2 DM in the present review revealed a positive change mainly towards a better glycemic control and comparatively lower risk of diabetes-related complication , by means of substantial increase in use of analogue insulin as well as introduction of novel glitazones from 1990-1999 to 2000-2008 in Turkey.