A large population-based study has found that middle aged people between 50-65 years, face twice the risk of developing mild cognitive impairment (MCI).

The Heinz Nixdorf Recall (Risk Factors, Evaluation of Coronary Calcium and Lifestyle) study, an observational, population-based, prospective study, examined 4,814 participants (50 percent men) between 2000 and 2003 in the metropolitan Ruhr area in Germany. After five years a second examination was conducted with 90 percent of the participants taking part.

For the analysis, 560 participants diagnosed with MCI were compared with 1376 cognitively normal participants. Of participants with MCI, 289 had amnestic MCI and 271 had non-amnestic MCI.

Interestingly, diabetes mellitus type 2 was strongly associated with MCI as well as MCI subtypes, but only in the middle-aged group, as in older participants (66-80 years) the association vanished. Examination of differences by gender revealed a stronger association of diabetes with amnestic MCI in middle-aged women and by contrast a stronger association with non-amnestic MCI in middle-aged men.

These results suggest that middle-aged individuals with diabetes mellitus type 2 are particularly vulnerable to MCI, with gender specific effects on subtypes of MCI. This underlines the importance of high quality treatment of diabetes especially in middle age, not only because of cardiovascular damage, but also because it might help to prevent or delay cognitive decline.

The study is published in the Journal of Alzheimer's Disease.