Effect of vascular burden as measured by vascular indexes upon vascular dementia: a matched case-control study

Background: Vascular dementia (VaD) is a challenging illness that affects the lives of older adults and caregivers. It is unclear how multiple vascular risk factor exposures (polyvascular disease) affect VaD. Purpose: To determine the relationship between multiple vascular risk exposures, as counted on an index in cases with VaD, compared with healthy age-/gender-matched controls. Methods: This was a matched case-control study of subjects living in Olmsted County, MN with documented VaD. Controls were selected by gender and age within 3 years from those who did not have dementia. The exposures included a total index (eleven exposure factors) added together, along with indexes for cerebrovascular disease (two exposures), cardiovascular disease (four exposures), vascular disease (three exposures), and lifestyle (two exposures). Analysis used matched conditional univariable logistic regression for each index. Results: A total of 1736 potential subjects were identified, and 205 subjects were diagnosed with VaD. There was a significant association of the total score index with an odds ratio of 1.45 (95% confidence interval 1.21-1.74). The cerebrovascular index was also associated with VaD with an odds ratio of 12.18 (95% confidence interval 6.29-23.61). The cardiovascular and vascular indexes were also associated with VaD status. The lifestyle index was not associated with VaD. Conclusion: The cumulative role of multiple vascular risk factors or diseases increased the risk of VaD, as noted by the total vascular index. The lifestyle index did not reveal any significant differences. Further work is required for evaluation of these indexes.