What would be the average lifespan of an adult, after being diagnosed with diabetes?

Too Complex for Data: There are too many variables to offer even a wild guess; such data more hollywood writers than physicians. Current age, age at onset, age when first started (before onset), how severe, how treated, in what ways, with what degree of success, potential complications of multiple interacting treatment strategies, how long would have lived without dm, etc. Are all huge & highly relevant variables.