Depressive symptoms, vascular risk factors and mild cognitive impairment: The Italian longitudinal study on aging

Aims: We evaluated the impact of depressive symptoms on the rate of incident mild cognitive impairment (MCI) after a 3.5-year follow-up, and we assessed the interaction between depressive symptoms and vascular risk factors for incident MCI. Methods: A total of 2,963 individuals from a sample of 5,632 65- to 84-year-old subjects were cognitively and functionally evaluated at the 1st and 2nd surveys of the Italian Longitudinal Study on Aging, a prospective cohort study with a 3.5-year follow-up. MCI and dementia were classified using current clinical criteria. Depressive symptoms were measured with the Geriatric Depression Scale. Results: Among the 2,963 participants, 139 prevalent MCI cases were diagnosed at the 1st survey. During the 3.5-year follow-up, 105 new events of MCI were diagnosed. We did not observe any significant association between depressive symptoms and incident MCI (RR = 1.25, 95% CI = 0.85-1.84, χ² = 1.30, p < 0.25). No sociodemographic variables or vascular risk factors modified the relationship between depressive symptoms and incident MCI. Conclusion: In our population, depressive symptoms were not associated with the rate of incident MCI. Our findings did not support a role of sociodemographic variables or vascular risk factors in the link between depressive symptoms and incident MCI.