Diabetes In Dogs Is It True That Doberman Dogs Suffer Diabetes When They Get Old, And That They Loose The Sense Of Smell As A C

Is it true that doberman dogs suffer diabetes when they get old, and that they loose the sense of smell as a c - diabetes in dogs

I was told that this dog is dangerous when they grow old because lose sight and smell, as a result of genetic diabetes. You do not even recognize his own master, and all attacks against him considered unknown. Is that true?