October 20 2023, Xin Xia defended her thesis entitled “Cardiovascular Health, Orthostatic Hypotension, and Cognitive Aging”. Xin, Could you tell us a little bit more?
The main aim of my thesis is to evaluate the associations of cardiovascular health and orthostatic hypotension (a significant drop in blood pressure after standing up from a lying position) with cognitive ageing in older adults.
Cardiovascular health was defined according to the American Heart Association’s Life’s Simple 7 (LS7) criteria, which consider seven well-known factors influencing cardiovascular health (smoking, body mass index, physical activity, diet, blood pressure, fasting plasma glucose, and total cholesterol). Both LS7-defined poor cardiovascular health and orthostatic hypotension have been associated with elevated risk of cardiovascular diseases and dementia in previous research.
We conducted epidemiological studies using data from the Swedish National Study on Aging and Care in Kungsholmen to further examine the role of LS7-defined cardiovascular health and orthostatic hypotension in cognitive aging in older adults.
What are the most important results?
We found that people with better cardiovascular health, defined by LS7, had a lower risk of developing dementia and longer life years spent in normal cognition. However, these results were only observed in younger old adults (e.g., <80 years) but not in older old adults (e.g., ≥80 years).
We also found that people with orthostatic hypotension were more likely to develop cardiovascular diseases and dementia in the future. The association between orthostatic hypotension and dementia seemed not to be fully explained by common vascular risk factors (e.g., hypertension, diabetes), comorbidities (e.g., heart failure, Parkinson’s disease), and frailty, which can increase the likelihood of having orthostatic hypotension.
How can this new knowledge contribute to the improvement of people’s health?
The findings have several implications. LS7 may be a useful tool for promoting cognitive health and prolonging cognitive impairment-free life years in younger old adults. However, LS7 may not be good enough to promote healthy cognitive ageing in older old adults.
Another implication of the findings is that orthostatic hypotension may be a potential modifiable risk factor for dementia. However, much more research needs to be done to establish whether orthostatic hypotension is a marker of subclinical or clinical conditions or is an independent risk factor for dementia. If orthostatic hypotension is an independent risk factor for dementia, it will be beneficial to manage orthostatic hypotension from the perspective of dementia prevention.
What are your plans right now and in the future?
I am looking for opportunities to continue conducting epidemiological research in the field of dementia and ageing in general in the future. In addition, I hope I can have opportunities to develop new methodologies that can help improve the quality of epidemiological studies and observational studies.
Link to the thesis: Cardiovascular health, orthostatic hypotension, and cognitive aging (ki.se)
Text by Charlotte Brandt