I was sitting in my GP’s office recently, being told something I didn’t want to hear. My blood pressure was too high and I needed to start medication with antihypertensives.

I didn’t want to have to take medication. I had always planned not to be on anything apart from fish oil and glucosamine supplements until I was at least 90 years old. I consider myself fit. I exercise daily, my weight is normal, I eat healthily, I don’t smoke and I keep an eye on how much wine I drink each week.

But my family history includes hypertension and stroke on both my mother’s and father’s side.
And I do recall a conversation with my obstetrician who was managing my pregnancy-induced hypertension a number of years ago. He said, “Jenny, you are likely to develop hypertension as you get older.” Harrumph. I heard, but didn’t want to listen. But who am I trying to kid?

I have what is called “essential hypertension”. The cause is as yet unknown.
I don’t like it. But I can deal with it and take my pills.
The reason why? Because I value my brain cells too highly not to. As a Doctor my medical training has taught me what the consequences of untreated hypertension are.

Hypertension has been described as a silent killer. You can’t feel if your blood pressure is too high. We rely on readings taken with a sphygmanometer to get an accurate idea of the state of our blood vessels.
The blood pressure reading essentially tells us the peak or systolic pressure our heart has to exert with each contraction to pump the blood around our body. The lower reading or diastolic pressure gives us the resting pressure of the circulatory system in between heartbeats.

If the readings are too high we run the increased risk over a period of time of blood vessel rupture causing a stroke or cerebrovascular accident. Other organs are affected as well, including the kidney, eye and heart. None of which is good news.

So, back to the brain and high blood pressure. Sure it’s good not to be at risk of stroke. But what about the effect of high blood pressure on memory and cognition?

Studies have shown that having high blood pressure can contribute to memory loss and other decline in brain function in people over the age of 45.

In one study of over 19000 participants aged 45 or older, they found that with each 10-point increase in diastolic pressure, the risk of cognitive difficulty increases by 7 points.

But how high is high?
We need to keep our diastolic pressure (the lower of the two reading indicating the pressure of the arterial system at rest) at below 90mmHg.

With around 25-30% of the Australia adult population having high blood pressure I am clearly not alone.
For the vast majority of people like myself we have “essential hypertension” where no specific cause is identified. However having high blood pressure causes problems by causing our arterial walls to thicken and lose their elasticity, leading to reduced blood flow and tissue death.

Having reduced blood flow to your brain becomes an issue when you need it to be working harder. For example when you want to be able to pay attention or work out a solution to a problem, the decrease of available blood flow to your brain leads to fewer brain cells being activated and an increased number of memory lapses happening as a result.

In older people, having high blood pressure can predict who is at risk of developing impaired executive function (organising, planning and decision making) and a greater risk of progressing to dementia. One study of 900 octogenarians showed that high blood pressure was associated with an increased risk of developing dementia when frontal lobe functioning was impaired

Because stroke and TIA are leading causes of risk of cerebrovascular disability followed by dementia, controlling hypertension is a simple and effective way to significantly potentially reduce the incidence of forecasted dementia in this group.

So attending to diagnosing and treating hypertension in midlife would appear to be essential to protect you from developing cognitive impairment further down the track.

If you are over 45 and haven’t had your blood pressure checked for a while, now would be a good time to make an appointment and get it checked by your GP.

If it is too high then some simple lifestyle changes could help:

• Keeping your weight in the healthy range
• Don’t smoke
• Reduce your alcohol consumption.
• Do some regular exercise
• Keeping your cholesterol in the normal range
• Eat less saturated fat.
• Use less salt in your diet.

Hypertension has no symptoms, but is easily managed and keeping it in the normal range could make a big difference to being able to save your brain.

References:
Shahram Oveisgharan; Vladimir Hachinski. Hypertension, Executive Dysfunction, and Progression to Dementia: The Canadian Study of Health and Aging. Arch Neurol, 2010; 67 (2): 187-192

JAMA and Archives Journals (2007, December 12). High Blood Pressure Associated With Risk For Mild Cognitive Impairment.

Radiological Society of North America (2007, November 29). High Blood Pressure May Heighten Effects Of Alzheimer’s Disease.

Now I do enjoy a nice glass of red wine occasionally and there is a lot of noise in the media about red wine being good for us.

Why? Because red wine contains resveratrol, an antioxidant with supposedly lots of health benefits such as protecting us from cancer, cardiovascular disease and perhaps cognitive decline.

Look in the health food shops selling memory enhancing supplements and many include resveratrol. You can even buy resveratrol in capsule form.

So should be we be taking these supplements or drinking more red wine?

Let’s have a look at what some of the research is saying about all this.

First off, resveratrol is not only found in red wine. It’s also found in a number of other plants and foods such as blueberries, mulberries, peanuts even eucalypt, lily and spruce. But it is grapes, which have drawn the most attention.
The grape vines contain resveratrol in the roots, stalks, seeds and especially the skin of the grape.
I think I’ll stick to the grapes and the skin.
In the fermentation process to make red wine, the skins which contain a lot of resveratrol are included. This is what differentiates it from white wine fermentation where only the crushed berry juice is used, not the skins.
Not all red wines are equal either. The highest concentrations of resveratrol are found in the Labrusca, Muscadine and Vitus Vinifera varieties.
Dr Richard Hoffman and Mr Johansson at the University of Hertfordshire, UK have been looking at a number of different red wines to determine which have the highest concentration of resveratrol. So that one day we will be able to select which wine we wish to purchase, based on it’s resveratrol content.

So how does resveratrol exert it’s health benefits in the brain?

Let’s look at a study on ischaemic stroke published in April 2010. Researchers from John Hopkins used resveratrol in mice studies and found that the resveratrol works to increase a neuro-protective enzyme (called haem oxygenase) Mice given resveratrol as supplements who then suffered an induced ischemic stroke, sustained less brain damage than those mice who had not received the supplement, because the resveratrol boosted the haem oxygenase levels.

Moving on to look at Alzheimer’s disease where having higher blood markers of inflammation is known to be associated with a higher risk of developing the disease. In the Framingham Heart Study, 691 healthy seniors (aged 79 years and older) had their levels of cytokines (markers of inflammation) measured in blood tests. Over the next 7 years, 44 of the participants developed Alzheimer’s disease.
The results showed that those with the highest levels of cytokine in their blood had twice the risk of developing Alzheimer’s disease.

So what’s the link to resveratrol and inflammation?

Resveratrol has been shown in mice studies to protect them from acute inflammation. Researchers in the Medicine Faculty in Glasgow demonstrated that resveratrol supplements helped to prevent the body from producing substances called sphingosine kinase and phospholipase D, which are involved in triggering the inflammatory response.

So how does resveratrol help to protect us from Alzheimer’s disease?

In Alzheimer’s disease, the main brain changes are massive brain cell loss and the appearance of neurofibrillary tangles and plaques of beta amyloid.
Ongoing studies indicate that resveratrol promotes the clearance of beta amyloid that has formed, by inducing the body’s proteasomes. The proteasomes are the body’s waste disposal units for getting rid of unneeded cellular proteins that can then be recycled. The mechanism for how resveratrol does this, as yet remains unknown.
All that is known is that in those people with Alzheimer’s disease, the natural activity of proteasomes is reduced.

Thus much of the story remains untold. As yet we don’t know which are the best red wines to be consuming, or the quantity to produce the beneficial effects. It may be that resveratrol itself is the messenger, a stimulator of other protective enzyme systems, rather than the major player in the process.

What we do know now is that resveratrol

• Increases a neuro protective enzyme called haem oxygenase that will help protect us to some extent, in the event of a stroke.
• Dampens down inflammation (a marker for increased risk of Alzheimer’s disease) in the body by reducing the amount of inflammatory enzymes that form.
• Promotes the body’s natural protein waste disposers, the proteasomes, which help clear the brain of beta amyloid deposits.

Until the remaining pieces of jigsaw are found to explain all of how resveratrol works, it would appear that continuing to enjoy a small amount of red wine is unlikely to be detrimental to our brain health and might even be doing us some good.