How does managing your blood pressure reduce your risk of dementia?

How does managing your blood pressure reduce your risk of dementia?

Hypertension is a risk factor for developing dementia later in life.  Effective blood pressure control and prevention of age-related hyper and hypotension, or high and low blood pressure, is vital for reducing dementia risk.  Several medications might be needed to reduce your risk of heart disease and vascular dementia, including antihypertensives, statins, and blood thinners.

This article discusses mainly how pharmacogenetic tests like Pillcheck can help reduce the risk of vascular dementia.  Vascular dementia is a type of dementia that makes up 10% of dementia cases, and is caused by blood vessel changes in the brain – strokes, for example.  Studies also show that good cardiovascular health helps to reduce progression of other forms of dementia, including Alzheimer’s Disease.  Pillcheck helps your doctor prescribe the right cardiovascular medications for you based on your genetics to better-treat cardiovascular issues.

Nearly 10% of adults over age 65 have dementia or another form of age-related cognitive decline such as Alzheimer’s.  With an aging population, the incidence of dementia is increasing the enormous burden on families and health systems.  The health of your blood vessels affects the risk of dementia – stroke, subclinical heart attack and changes in the brain’s white matter caused by reduced oxygen supply leads to vascular dementia.  Furthermore, inadequate blood supply worsens disease progression in people with other forms of dementia, such as Alzheimer’s, that are caused by the accumulation of tau-protein and amyloid plaques.

Your blood pressure impacts the risk of dementia

MRI imaging studies show that ischemic microvascular brain disease, which causes damage to the white matter of your brain, is widespread and affects 70% of people over 60.  More severe cases of this disease, such as TIA (transient ischemic attack) and stoke are observed less frequently.  Damage to the white matter of your brain is a leading cause of dementia.  While no medications are available today to prevent Alzheimer’s disease and other forms of dementia, better blood pressure control can reduce the risk of vascular dementia.  Reducing your risk of vascular dementia can help to reduce your risk of other forms of dementia because maintaining good cardiovascular health is known to reduce your risk of many forms of dementia.

Long term observational studies have consistently linked midlife hypertension to cognitive impairment later in life.  A recent prospective study called Atherosclerosis Risk in Communities (ARIC) showed that in mid-life (people aged 54-63 with hypertensive blood pressure over 140/90 mm Hg) there is an increased incidence of dementia later in life.  People with hypertension had a 1.41 times higher rate of dementia compared to people with normal blood pressure in mid-life.

Ironically, people with low blood pressure (below 90/60 mm Hg), also had a significantly elevated risk of late-life dementia, a 1.62 times higher rate.  Low blood pressure in late life is a significant factor in dementia development due to insufficient blood flow in the brain.

This study demonstrates that dementia may start developing in midlife, decades before the clinical manifestation of cognitive decline, and highlights the importance of adequate blood pressure control.

The SPRINT MIND study showed that bringing blood pressure below 120/80 mm Hg was more advantageous when compared to a group in the study with a less aggressive blood pressure target of 140/90 mm Hg.  The ARIC study also found that progressive age-related decline in blood pressure in people with hypertension in mid-life is associated with reduced cognitive abilities.

Proactive blood pressure management in midlife, close monitoring, and an age-appropriate gradual reduction in antihypertensive drug dose is essential to maintain optimal blood pressure over your lifetime.

If applied in midlife, intensive hypertension management with lower blood pressure targets of 120/80 mm Hg may preserve cognitive function.  Diet, exercise, and cognitive training in elderly patients also slows down cognitive decline.  However, lifestyle interventions have a lower effect than tight blood pressure management.

Prevention of excessive blood clotting for people with atrial fibrillation with anticoagulants is needed to prevent stoke, which is one of the leading causes of dementia.

If you are over 50 years of age and have a history of hypertension, you should consult your doctor on how to manage your blood pressure both through diet and medications.  Diet alone might not provide sufficient blood pressure reduction to the desired target of 120/80 mm Hg; an antihypertensive drug might be needed.

Pharmacogenetics can improve blood pressure control and reduce side effects

Excessive doses of blood pressure-lowering drugs can cause dizziness and increase the risk of falls.  Fall-related hip fractures are one of the leading causes of mortality for the elderly. Pharmacogenetic tests such as Pillcheck can help your doctor to understand how your body processes various medications and select appropriate drugs and doses.

Cholesterol management is also a necessary component for dementia prevention.  A recent French study showed that stopping statins in people over 75 years of age increased the number of cardiovascular events, and hence also leads to increased risk of dementia.  If you have elevated cholesterol and triglycerides that are not in the desired range even with a restricted diet, your doctor should also prescribe a statin for you.

Over 18% of people taking statins experience severe muscle and joint pain, called statin-induced myopathy triggered by reduced statin metabolism.  Unmanaged, excessive statin doses can lead to kidney failure, especially when patients are co-administered drugs that slow down statin metabolism such as clarithromycin and other drugs.  Variations in the SLCO1B1 gene have been linked to an increased risk of statin-induced myopathy.  For patients who carry a minor, or single risk variant, the CPIC recommendation is to reduce statin dose.  CPIC is the organization that issues guidelines on medications based on pharmacogenetic testing.  Patients with what is known as a “double variant” are regarded as statin-intolerant, and an alternative treatment to statins should be considered to reduce the long-term health risks.

Antihypertensive drugs, anticoagulants, antiplatelets and statins should be used at the right dose to ensure efficacy and safety.

If you are over 50 and have elevated blood pressure or family history of dementia, a pharmacogenetic test can help you to optimize your medications and reduce the risk of medication-induced side effects.  Pillcheck can provide insights on your metabolism and response to blood pressure medications, statins, analgesics, antidepressants and many other drugs.  Since your DNA does not change Pillcheck results will serve as a personalized prescribing guide over your lifetime.

Conclusions:

  • Effective blood pressure control is essential to reduce the risk of dementia
  • Multiple medications might be needed to manage the risk of heart disease and dementia
  • Pharmacogenetic testing can help physicians to select the appropriate drug and dose to pro-actively manage your condition and reduce your risk of dementia.

Selected references:

Walker KA, at al., Association of Midlife to Late-Life Blood Pressure Patterns With Incident Dementia JAMA. 2019;322(6):535-545.

The SPRINT MIND Investigators for the SPRINT Research Group Effect of Intensive vs Standard Blood Pressure Control on Probable Dementia A Randomized Clinical Trial JAMA. 2019;321(6):553-561.

Ngandu T, Lehtisalo  J, Solomon  A,  et al.  A 2 year multidomain intervention of diet, exercise, cognitive training, and vascular risk monitoring versus control to prevent cognitive decline in at-risk elderly people (FINGER) Lancet. 2015;385(9984):2255-2263

Mok VC, Lam  WW, Fan  YH,  et al.  Effects of statins on the progression of cerebral white matter lesion.  J Neurol. 2009;256(5):750-757

Ramsey LB et al., The Clinical Pharmacogenetics Implementation Consortium Guideline for SLCO1B1 and Simvastatin-Induced Myopathy: 2014 Update CLINICAL PHARMACOLOGY & THERAPEUTICS 2014

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