Major increase in Type 1 diabetes: no support for the Accelerator Hypothesis.

Background: The Accelerator Hypothesis postulates that the apparent increase in incidence of Type 1 diabetes mellitus (T1DM) is related to an acceleration of disease onset by weight-related insulin resistance. Our diabetes clinic has experienced a major recent increase in newly diagnosed diabetes. The Accelerator Hypothesis predicts that this increase should be associated with younger age and increased body mass at diagnosis, with youngest children having the highest body mass index (BMI).

Aim: To test the Accelerator Hypothesis in the context of the major increase in T1DM at our centre.

Methods: Data from all young people diagnosed with T1DM between 1992 and 2003 were reviewed. Height and weight measurements from initial outpatient review were used to calculate BMI.

Results: The mean increase in BMI standard deviation score (SDS) is 0.03 per year (P = 0.01). Age at diagnosis has also increased by a mean of 0.11 years annually (P = 0.003). There was no association between BMI SDS and age at diagnosis (P = 0.7). A significant difference in BMI SDS between age-banded subgroups was evident (P = 0.04); however, youngest children had the lowest SDS.

Conclusion: Our results do not support increased body mass as an accelerator of diabetes presentation.