Type 1 diabetes in Cheshire: cardiometabolic risk factor trends (2004-2009).

Aims: In the context of changes in the last 10 years in treatment strategies for type 1 diabetes we evaluated longitudinal trends in cardiometabolic risk factor profiles in a population from North-West England.

Methods: We retrospectively examined longitudinal case records for the period for 291 adult patients followed up between 2004 and 2009 (age range 16-85). Data search was performed through the EMIS® software provider using data held in primary care.

Results: Longitudinal analysis of individually followed patients indicated a mean 0.4% reduction in HbA1c from 8.3% (67 mmol/mol) at baseline (p=0.002). The proportion of patients with an HbA1c ≥10% (86 mmol/mol) at baseline had a significant reduction over time from 14.0% to 9.5% (χ(2)=9.4, p=0.002). BMI remained unchanged (28.3 vs 28.4 kg/m(2)). However total cholesterol fell by 12.5% from 4.8mM to 4.2mM, (p<0.0001) with a corresponding 23% reduction in LDL-cholesterol from 3.0mm to 2.3mM (p<0.0001). There was a significant fall in diastolic BP (78-74 mmHg, p=0.0016). In a mixed longitudinal regression model, HbA1c was associated with LDL-C (β=0.28, p<0.001) and age (β=0.02, p=0.001), independent of BMI, gender and systolic BP.

Discussion: In spite of intensive work to improve glycaemic control in type 1 diabetes, mean HbA1c remains above target for many people in our area, highlighting the difficulty of achieving glycaemic targets in type 1 diabetes. The significant reduction in diastolic BP, LDL and total cholesterol may have long-term benefit in cardiovascular event rate reduction.