**Abstract**

People with diabetes mellitus type 2 will have higher rate of cognitive impairment than people that do not. Besides that, the effect of diabetes on the normal mental functions is often disregarded. This may be due to a lack of signs and standard assessment technique to measure the cognitive function of the diabetes patient. Hyperglycaemia which is common in people with diabetes has been associated with an increase in the possibility of developing Alzheimer's disease and vascular dementia in the both general public and people with cognitive impairment. It has been estimated that an individual with diabetes mellitus is 1.5 times more likely to experience cognitive dysfunction and dementia than a normal healthy individual. Alleviation of microvascular complications and hypoglycaemia is the key in treatment of DM to prevent cognitive decline.

**Keywords:** diabetes, cognition, age, glucose impairment, HbA1c
