Diabetes mellitus is one of the most common hormonal medical conditions in cats.   Sometimes referred to as sugar diabetes, diabetes mellitus is caused by a lack of insulin.   Insulin is required to regulate glucose in the body and in the absence of insulin the cat will become hyperglycaemic.
This is mainly seen in middle-aged and older cats and is more common overweight cats.   Some breeds of cat have also been shown to be more susceptible, e.g. Burmese.  The f