Abstract

Aims: To prospectively determine the change in prevalence of microalbuminuria in relation to changes in glycaemic control in children diagnosed with type 1 diabetes between 1986 and 1996.

Design: Prospective observational study of an inception cohort.

Setting: The geographically defined region of Oxfordshire, UK.

Patients: 527 children diagnosed with type 1 diabetes under 16 years of age, were divided into three groups based on year of diagnosis of diabetes: group A (1986–1989, n = 165), group B (1990–1993, n = 179) and group C (1994–1996, n = 183). Each group was followed prospectively for 10 years.

Main outcome measures: Cumulative prevalence of microalbuminuria.

Results: After 4052 patient years of follow-up, in groups C versus B versus A, the cumulative prevalence of microalbuminuria was 31.7% (95% CI 20.9 to 42.5), 24.8% (17.8 to 31.8) and 23.2% (15.4 to 30.0) (log rank p = 0.22), and risk for development of microalbuminuria was not associated with year of onset of diabetes (hazard ratio 1.05 (0.99 to 1.12), p = 0.11). In groups C versus B versus A, glycaemic control improved after 10 years of diabetes (mean HbA1c 8.9% (1.5%) vs 9.4% (1.5%) vs 10.1% (1.7%), p value for ANOVA <0.001) and more children achieved an HbA1c level <7.5% (15.6% vs 5.9% vs 6.1%, p value for ANOVA = 0.032).

Conclusion: In this UK based inception cohort of children diagnosed with type 1 diabetes, the adjusted prevalence of microalbuminuria was unchanged since 1986, despite some improvements in glycaemic control. This observation highlights the need for more proactive intervention with drugs such as angiotensin converting enzyme (ACE) inhibitors.