Incident occurrence of depressive symptoms among patients with mild cognitive impairment. The Italian Longitudinal Study on Aging

AIMS: We estimated the prevalence and incidence rates of depressive symptoms and the role of vascular risk factors and sociodemographic variables on the occurrence of depressive symptoms in mild cognitive impairment (MCI). METHODS: In the Italian Longitudinal Study on Aging, 2,963 individuals from 5,632 65- to 84-year-old subjects were evaluated at the 1st and 2nd survey, with a 3.5-year follow-up. Dementia and MCI were classified using current criteria. Depressive symptoms were measured with the Geriatric Depression Scale. RESULTS: Among the 2,963 participants, 139 prevalent MCI cases were diagnosed with a depressive symptoms prevalence rate of 63.3%. During the 3.5-year follow-up, we estimated an incidence rate of depressive symptoms of 29.6 per 100 person-years. No sociodemographic variables or vascular risk factors modified the incidence of depressive symptoms in cognitively stable MCI patients or in MCI patients who reverted to normal cognition. CONCLUSION: In our population, there was a high prevalence and incidence of depressive symptoms in MCI. Our findings do not provide support for a possible role of vascular risk factors in the development of depressive symptoms in MCI, although these findings were based on relatively few cases of MCI, limiting the capacity to draw definitive conclusions.