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 HbA1c: 6.84 (±1.5), were analyzed. There has been a progressive decline in HbA1c levels (HbA1c > 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 < 100mg/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.