Aims To review glycaemic control and rate of microvascular complications in adolescents and young adults with childhood onset type 1 diabetes and to investigate glycaemic control before and after transfer to adult services.

Methods All patients aged 17 to 23 years with childhood onset type 1 diabetes at a single tertiary centre were included. Patients were identified using our clinic database. Details of treatment control and complications were obtained from the database.

Results A total of 104 (male=55) patients with a median age of 19.2 (17.15 to 23.0) years were identified with mean (±SD) duration of diabetes of 9.7 (±4.4) years. Treatment consisted of multiple daily injections in 66.3%, pump therapy in 27.9% and twice daily insulin regimen in 5.8%. Mean HbA1c was 77.3 ± 17.9 mmol/mol, comparable to results seen in similar studies. Hypothyroidism and coeliac disease was detected in 6.7% and 3.8%, respectively. Microalbuminuria was noted in 8.6% and retinopathy in 43.2%, with one patient requiring laser therapy. Mean LDL was 2.3 ± 0.67 mmol/l with one patient on statin therapy. The mean systolic and diastolic blood pressures were 122 ± 11 and 71.4 ± 8.9 mmHg, respectively.

The mean age of transfer to adult services was 18.5 ± 1.2 years. Mean HbA1c in the year before transfer was 77.8 ± 18.1 mmol/mol with similar levels one year post transfer at 78.3 ± 18.3 mmol/mol. Only 12.5% of individuals achieved target HbA1c of <58 mmol/mol. There was a reduction in average number of clinics attended post transfer (3.2 Vs 2.4 in one calendar year) with three patients lost to follow up after transfer. Hospital admissions halved post transfer from 6 admissions over 3 years before transfer to 3 admissions after transfer.

Conclusions Diabetes control in adolescent and young adults with type 1 diabetes is inadequate and is not affected by transfer to adult services, despite a reduction in the number of clinic attendance. The rate of microvascular complications in this group is relatively high, although advanced complications were evident only in a minority. Future work is needed to improve glycaemic control in young people with diabetes to encourage engagement and develop new strategies for self management.