Metabolic control and cardiovascular risk factors in type 2 diabetes mellitus patients according to diabetes duration

Background. Control of glycaemic levels as well as cardiovascular risk factors (CVRF) is essential to prevent the onset of complications associated with type 2 diabetes mellitus (T2DM). Aim. To describe the degree of glycaemic control and CVRF in relation to diabetes duration. Patients and methods. Multicentre cross-sectional study in T2DM patients seen in primary care centres during 2007. Variables: Demographical and clinical characteristics, antidiabetic treatments and development of disease complications. Diabetes duration classification: 0-5, 6-10, 11-20 and >20 years. Logistic regression models were used in the analysis. Results. A total of 3130 patients; 51.5% males; mean age: 68 +/- 11.7 years; mean diabetes duration: 7.0 (+/- 5.6) years, median: 5 (interquartile range:3-9) years; mean HbA(1c) : 6.84 (+/- 1.5), were analyzed. There has been a progressive decline in HbA(1c) levels (HbA(1c) > 7% in 25.8% of patients during the first 5 years and 51.8% after 20 years). Blood pressure values remained relatively stable throughout disease duration. The mean value of low density lipoprotein (LDL) experienced a slight decline with the progression of the disease, but due to the significant increase of cardiovascular disease (CVD) after 20 years of duration, less patients reached the recommended target (LDL < 100 mg/dl) in secondary prevention. Logistic regression model controlling for age, sex and CVD showed that diabetes duration was related to glycaemic control (odds ratio: 1.066, 95% confidence interval: 1.050-1.082 per year) but not to blood pressure or LDL control. Conclusions. The degree of glycaemic control and the risk factors in relation to the duration of T2DM followed different patterns. Diabetes duration was associated with a poorer glycaemic control but in general had a limited role in blood pressure control or lipid profile.