Summary: A new study reports having high blood pressure can raise the risk of developing vascular dementia.
Source: George Institute for Global Health.
High blood pressure could significantly raise the risk of developing the second most common form of dementia, according to a new study from The George Institute for Global Health.
The medical records of more than four million people were analysed with researchers finding heightened blood pressure was associated with a 62 per cent higher risk of vascular dementia between the ages of 30-50.
Lead author Professor Kazem Rahimi, of The George Institute for Global Health, said: “Vascular dementia rates are increasing all over the world and will pose a significant economic and social burden in both developed and developing countries. So these results are particularly important.
“We already know that high blood pressure can raise the risk of stroke and heart attack. Our research has shown that high blood pressure is also associated with a significantly higher risk of vascular dementia.”
- The team at The George Institute analysed the medical records of 4.28 million people.
- They found over a seven year period 11,114 people went onto develop vascular dementia.
- The study found patients aged 30-50, who had high blood pressure, had a 62 per cent higher risk of vascular dementia, and a 26 per cent higher risk at age 51-70.
- The study also found that high blood pressure was still a risk factor even after adjusting for the presence of stroke, the leading cause of vascular dementia.
Professor Rahimi, deputy director of The George Institute UK, said: “Our results suggest that lowering blood pressure, either by exercise, diet or blood pressure lowering drugs, could reduce the risk of vascular dementia.”
Vascular dementia affects around 9.3 million people globally and is caused by reduced blood supply to the brain due to diseased blood vessels.
High blood pressure cause problems by damaging and narrowing the blood vessels in the brain. Over time, this raises the risk of a blood vessel becoming blocked or bursting. It’s a known risk factor for stroke and cardiovascular disease but until now studies were conflicting over the risks for vascular dementia with several even indicating that low blood pressure was associated with an increased risk of dementia.
Funding: Funding information is not available.
Source: Julia Timms – George Institute for Global Health
Image Source: This NeuroscienceNews.com image is for illustrative purposes only.
Original Research: Abstract for “Blood Pressure and Risk of Vascular Dementia: Evidence From a Primary Care Registry and a Cohort Study of Transient Ischemic Attack and Stroke” by Connor A. Emdin, HBSc, Peter M. Rothwell, FMedSci, Gholamreza Salimi-Khorshidi, DPhil, Amit Kiran, PhD, Nathalie Conrad, MSc, Thomas Callender, MBChB, Ziyah Mehta, DPhil, Sarah T. Pendlebury, DPhil, Simon G. Anderson, PhD, Hamid Mohseni, PhD, Mark Woodward, PhD and Kazem Rahimi, DM, MSc in Stroke. Published online April 13 2016 doi:10.1161/STROKEAHA.116.012658
http://neurosciencenews.com/ascualr-dementia-blood-pressure-4250/ (accessed May 18, 2016).
Blood Pressure and Risk of Vascular Dementia: Evidence From a Primary Care Registry and a Cohort Study of Transient Ischemic Attack and Stroke
Background and Purpose—Vascular dementia is the second most common form of dementia but reliable evidence on age-specific associations between blood pressure (BP) and risk of vascular dementia is limited and some studies have reported negative associations at older ages.
Methods—In a cohort of 4.28 million individuals, free of known vascular disease and dementia and identified from linked electronic primary care health records in the United Kingdom (Clinical Practice Research Datalink), we related BP to time to physician-diagnosed vascular dementia. We further determined associations between BP and dementia in a prospective population-based cohort of incident transient ischemic attack and stroke (Oxford Vascular Study).
Results—For a median follow-up of 7.0 years, 11 114 initial presentations of vascular dementia were observed in the primary care cohort after exclusion of the first 4 years of follow-up. The association between usual systolic BP and risk of vascular dementia decreased with age (hazard ratio per 20 mm Hg higher systolic BP, 1.62; 95% confidence interval, 1.13–2.35 at 30–50 years; 1.26, 1.18–1.35 at 51–70 years; 0.97, 0.92–1.03 at 71–90 years; P trend =0.006). Usual systolic BP remained predictive of vascular dementia after accounting for effect mediation by stroke and transient ischemic attack. In the population-based cohort, prior systolic BP was predictive of 5-year risk of dementia with no evidence of negative association at older ages.
Conclusions—BP is positively associated with risk of vascular dementia, irrespective of preceding transient ischemic attack or stroke. Previous reports of inverse associations in old age could not be confirmed.
“Blood Pressure and Risk of Vascular Dementia: Evidence From a Primary Care Registry and a Cohort Study of Transient Ischemic Attack and Stroke” by Connor A. Emdin, HBSc, Peter M. Rothwell, FMedSci, Gholamreza Salimi-Khorshidi, DPhil, Amit Kiran, PhD, Nathalie Conrad, MSc, Thomas Callender, MBChB, Ziyah Mehta, DPhil, Sarah T. Pendlebury, DPhil, Simon G. Anderson, PhD, Hamid Mohseni, PhD, Mark Woodward, PhD and Kazem Rahimi, DM, MSc in Stroke. Published online April 13 2016 doi:10.1161/STROKEAHA.116.012658