This is important for two reasons, study author Dr Meena Kumari told Reuters Health. "Firstly, diabetes is associated with poorer cognitive performance in younger age groups, which suggests that diabetes itself is associated with cognitive decline. Secondly, as the incidence of diabetes in younger age groups is increasing, this has implications for the management of diabetes in these groups."

It is also worth noting, Kumari continued that, "we found a poorer cognitive function score in those that had been diagnosed (with diabetes) as early as two to five years previously and that it was explained by the metabolic abnormalities associated with diabetes."

For their research, Kumari and her colleague Dr. Michael Marmot, both from the International Center for Health and Society in London, UK, examined ties between diabetes and cognitive performance in 4,020 men and 1,627 women whose average age was 56. These individuals were participants in a study that began in 1985-1988.

By 1997-1999, a total of 208 men (5 percent) and 101 women (6 percent) had developed diabetes while 405 men (10 percent) and 192 women (12 percent) had impaired glucose tolerance, a pre-diabetic condition.