"...there are surprisingly few large-scale assessments of life expectancy in the historical literature, but what there are point to some evidence that this is improving for people with Type 1 diabetes." [Ref 1]
Reference
Life expectancy greatly improved in Type 1 diabetes (25 September 2013) Medscape - reporting on a poster presentation by Helen Colhoun (of diabetes epidemiology unit at University of Dundee, Scotland) on lessening of the gap in life expectancy between people with Type 1 diabetes and those without.