Lower baseline BMI has been associated with more rapid cognitive decline in MCI [Cronk B et al., 2010] while data considering risk of progression to an overt dementia is lacking.

To examine the potential relationship between baseline BMI and changes in BMI over time and the risk of MCI-todementia progression.

Fifty four subjects with MCI were observed longitudinally over the period of 24 months. BMI was measured at baseline and yearly. Demographic and clinical (including the presence of concomitant somatic diseases and neuropsychiatric symptoms) data was collected at baseline. After conducting univariate comparisons, factors which p was <0,15 were entered into multivariate models.

Subjects with MCI who progressed to dementia had lower BMI at baseline (mean values 19,6 vs 22,5; p<0,001) and were losing more weight over time (mean values of BMI change over 2 years -1,3 vs -6,5; p<0,001). In multivariate analysis higher baseline BMI remained as a protective factor (OR=0,6; 95% CI 0,4-0,9) while losing weight over time (OR=1,3; 95% CI 1,1-1,5) and apathy could be considered as risk factors. Interestingly the presence of apathy was correlated to lower BMI values both at baseline and over time.

Both lower baseline BMI and a tendency for continuing weight lost over time may be factors related to risk of MCI-to-dementia progression. Correlation of nutritional status measured by BMI with apathy merits further exploration.