Cardiovascular and biochemical risk factors for incident dementia in the Hypertension in the Very Elderly Trial.J Hypertens 2009; 27(10):2055-62JH
Several cardiovascular and biochemical factors including hypertension have been associated with cognitive decline and dementia, although both epidemiological and intervention evidence is mixed with the majority of studies examining those in midlife or younger elderly and the recent Hypertension in the Very Elderly Trial showing no significant association between blood pressure lowering and incident dementia. It has also been suggested that risk factors may differ in the very elderly. The aim of these analyses was to examine the impact of baseline cardiovascular and biochemical factors upon incident dementia and cognitive decline in a very elderly hypertensive group.
Participants of the Hypertension in the Very Elderly Trial were aged at least 80 years and hypertensive. Cognitive function was assessed at baseline and annually with diagnostic information collected for dementia and relationships between baseline total and high-density lipoprotein cholesterol, creatinine, glucose, haemoglobin, heart failure, atrial fibrillation, diabetes, previous stroke and later dementia/cognitive decline were examined.
There were 3336 participants with longitudinal cognitive function data. In multivariate analyses higher creatinine was associated with a lower risk of incident dementia and cognitive decline. Higher total and lower high-density lipoprotein cholesterol were associated with lower risk of cognitive decline. Other variables were not significant.
In very elderly hypertensive patients heart failure, diabetes, atrial fibrillation, prior stroke, glucose and haemoglobin levels did not demonstrate a relationship with cognitive decline or dementia. Higher creatinine (excluding moderate renal impairment) was associated with a lower risk of dementia and cognitive decline. The findings for total and high-density lipoprotein cholesterol add to the varied literature in this area and together these findings may add weight to the suggestion that risk factor profiles differ in the very elderly.