I have type 1 diabetes (for 48 years). I have a son who was diagnosed with Aspergers at age 3 and with T1D at age 4. In my community of 200,000 people, we know of 5 cases of both Aspergers and T1D occurring together. That incidence seems much higher than would be expected if the two rare disorders were independent. There is a small body of scientific literature that supports that autism (including Aspergers) has an autoimmune etiology. And it is well established that if a person has one autoimmune disease, they are at much higher risk of other autoimmune diseases.
For all the Aspergers people I know, there is a near-unamimous comfort with regimentation and a consistent life schedule. I guess the blessing in disguise with Aspergers and diabetes is that scheduled living is great for diabetes management.