Glycaemic control and lipid concentrations in a cohort of people with diabetes over 7 years of follow-up: a regional audit of diabetes care in the UK

Abstract

Aim: To determine changes in glycaemic control and lipids over time since the introduction of the Quality and Outcomes Framework.

Methods: In adults with diabetes (Hampshire, UK), HbA1c and lipid measurements were retrieved from a regional National Health Service biochemical database in 2006 and 2013 and analysed using anova and logistic regression modelling.

Results: In 2006, 8568 people with diabetes were identified. In 2013, 5815 had follow-up data, 1207 people were lost to follow-up and 1546 had died. At baseline, HbA1c concentrations were 62.1 ± 16.1, 64.7 ± 16.7 and 64.5 ± 17.6 mmol/mol for those with follow-up data, those lost to follow-up and those who died, respectively. The mean age was 60.2 ± 14.5, 57.6 ± 18.0 and 73.9 ± 10.5 years, respectively, for the three groups. Total cholesterol, HDL cholesterol and triglyceride concentrations were similar between groups. The mean HbA1c concentration for those with complete follow-up data was 62.1 ± 16.1 mmol/mol in 2006 and 61.7 ± 17.3 mmol/mol in 2013. Quality and Outcomes Framework targets for cholesterol (< 5 mmol/l) were achieved by 79% of people in 2006 and 83% in 2013 (P < 0.001). Baseline age and HbA1c were associated with death at follow-up: the odds ratio per year increase in baseline age was 1.10 (95% CI 1.09-1.10; P < 0.001) and per unit increase in HbA1c it was 1.02 (95% CI 1.02-1.03; P < 0.001).

Conclusions: Glycaemic control showed remarkable stability over 7 years of follow-up, despite increasing patient age and duration of diabetes. More patients achieved lipid targets in 2013 than in 2006. Although baseline HbA1c was a predictor of death at follow-up, baseline HbA1c differed little between survivors, non-survivors and those lost to follow-up.