Are depressive symptoms in mild cognitive impairment predictive of conversion to dementia?

Background: Depressive symptoms are common in amnestic mild cognitive impairment (aMCI). The association between depressive symptoms and conversion to dementia is not yet clear. This longitudinal study was conducted to ascertain whether depressive symptoms in aMCI patients are predictive of conversion to dementia. Methods: 35 aMCI patients participated in this study. All participants underwent cognitive testing and were administered the geriatric depression scale (GDS) to determine the presence of depressive symptoms. A score equaling or higher than 11 on the GDS was taken as the cut-off point for presence of significant depressive symptoms. Conversion to dementia was assessed at follow-up visits after 1.5, 4, and 10 years. Results: 31.4% of the patients reported depressive symptoms at baseline. None of the cognitive measures revealed a significant difference at baseline between patients with and without depressive symptoms. After 1.5, 4, and 10 years respectively 6, 14, and 23 patients had converted to dementia. Although the GDS scores at baseline did not predict conversion to dementia, the cognitive measures and more specifically a verbal cued recall task (the memory impairment scale-plus) was a good predictor for conversion. Conclusions: Based on this dataset, the presence of depressive symptoms in aMCI patients is not predictive of conversion to dementia.