Adult‐onset type 1 diabetes: Predictors of glycaemic control

AIMS: Knowledge about adult‐onset (AO) type 1 diabetes remains insufficient. We sought to characterize the initial 5 years of AO type 1 diabetes and hypothesized that initial factors predictive of subsequent glycaemic control might exist. MATERIALS AND METHODS: A retrospective cohort study based on electronic medical records of 280 subjects with newly diagnosed AO type 1 diabetes (>18 years of age, excluding secondary and latent autoimmune diabetes) with available data for the initial 5‐year treatment. RESULTS: Characteristics at diagnosis: 61% men, mean age 37 ± 12 years, BMI 23 ± 3.3 (kg/m(2)), systolic/diastolic blood pressure: 123 ± 15/76 ± 9 mm Hg and LDL cholesterol: 2.9 ± 0.9 mmol/L. HbA1c decreased from 106 mmol/mol (11.8%) at diagnosis to 52 mmol/mol (6.9%) at 6 months and then increased gradually to 67 mmol/mol (8.3%) after 5 years. Strict glycaemic control (<53 mmol/mol (7%)) was achieved by 66% within 6‐9 months and 30% after 5 years. Comparing patients with and without strict glycaemic control after 5 years revealed no differences in HbA1c, C‐peptide or any other diabetes‐related parameter at the time of diagnosis. However, reaching strict control within 6‐9 months after diagnosis was strongly associated with remaining in strict control after 5 years (OR: 9.2 (CI‐95% 4.0‐20.9; P < 0.0001)). Conversely, patients who did not achieve early strict control were very unlikely to be well controlled after 5 years. CONCLUSIONS: Long‐term tight glycaemic control in subjects with AO type 1 diabetes is both achievable and to some extent predictable. Whether alternative strategies shortly after diagnosis would benefit patients with insufficient glycaemic control should be investigated.