Cerebrovascular disease in the elderly: lipoprotein metabolism and cognitive decline

Data concerning the treatment of lipoprotein disturbances in patients with cerebrovascular disease (CVD) are less robust than those for coronary heart disease (CHD), raising clinical questions as to which is the appropriate therapeutic approach to stroke patients. Although observational cohort studies have failed to demonstrate an association between lipoprotein disorders and stroke incidence, recently completed trials of subjects at risk for CHD have shown that statins reduce not only the risk of myocardial infarction and death, but also that of brain infarction and transient ischemic attacks. At present, it seems reasonable to conclude that stroke patients with undesirable lipid profiles who have a history of CHD should receive specific treatment for the lipid disorder. Recommendations are more problematic for stroke patients with lipid disorder but no history of CHD. Furthermore, many of the risk factors for CVD and vascular dementia (VaD), including serum total cholesterol (TC), lipoprotein(a), diabetes, atrial fibrillation, hypertension, apolipoprotein E levels, and atherosclerosis, have also been shown to increase the risk of Alzheimer's disease (AD). In a recent study, we estimated the prevalence, incidence and rate of progression of Mild Cognitive Impairment (MCI) to dementia, and correlated vascular risk factors with incident MCI and its progression to dementia. We evaluated 2963 individuals from the population-based sample of 5632 subjects 65-84 years old of the Italian Longitudinal Study on Aging, with a 3.5-year follow-up. We found a progression rate to dementia (all causes) of 3.8/100 person-years. Furthermore, age was a risk factor for incident MCI, while education was protective, and serum TC evidenced a non-significant borderline trend for a protective effect. There was a non-significant trend for stroke as a risk factor of progression of MCI to dementia. In conclusion, in our population, among MCI patients who progressed to dementia, 60% progressed to AD and 33% to VaD. Vascular risk factors and CVD may influence the development of MCI and the rate of progression to dementia.