Hypertension and its management

Hypertension and its management

By Bruce Rogan, E & OE

This is a layman’s view, but it has the unique attribute of coming from a completely impartial perspective. Unfortunately, nearly every other source of information on this topic is loaded with commercial agendas, including, sadly, those of your doctor. If doctors got their incomes from the State, as many argue they should, their tendency to give less-than-impartial advice might be reduced. GPs have to live, and like everyone else, they like to live as well as they reasonably can. The idea of a set of patients who are generally quite well, but who have been persuaded that they need to visit a doctor regularly to get drugs that they cannot get any other way, is a most attractive proposition, to both the doctor and the drug manufacturer. This is not an attack on doctors; it is simply an observation about human nature, of which the most common feature is greed.

About Hypertension

An important hormone that influences the output pressure of the heart is called angiotensin.
There is an enzyme produced in the adrenal gland (or somewhere near there) that activates this hormone. It is called kinninase II, although it is better known (rather prosaically) as angiotensin converting enzyme. (ACE).
A drug called Enalapril (Chemical name: L-Proline, 1-(N-(1-(ethoxycarbonyl)-3-phenylpropyl)-L-alanyl)-, (S)- ) inhibits this enzyme’s function and, while other things will do this, all the others found so far have significant side effects. It is a so-called ACE inhibitor, and has several different trade names. At the time of writing, the variant that is subsidised by the New Zealand drug agency is called ACCUPRIL.

The most common side effect is an irritation that makes you cough. In some people this gets so bad they have to stop taking it. The author of this article has had a slight cough from time to time but now seems to have developed immunity.

Blood pressure is generated by the heart, and controlled by a whole raft of other subsystems in your body. The organs that have the biggest impact on your blood pressure are your kidneys. They are at the far end of the blood circulation system. Any toxins and waste products picked up by the blood as it travels round the body are eliminated by passing it all through the kidneys. Diseases of the kidney can upset their ability to send the correct pressure regulation information to the heart. The author has his own suspicions as to why so many people seem to suffer from hypertension in New Zealand, compared with relatively so few in a lot of European countries. It is not necessary to believe unquestioningly that it is all due to genetics.

The companion drug that is commonly administered with the ACE inhibitor (whose task is to reduce the output pressure) is a so-called vaso-dilator that relaxes the muscles of the venous return system so that the used blood can get back to the lungs more easily. The trade name of the subsidised stuff is Plendil. The simple chemical name is felodipine. ACE inhibitors do more than just suppress the operation of Kinninase II. They also facilitate passage of blood through the kidneys by dilating the tiny blood vessels called glomeruli that filter out the waste products. Fortunately, the way they act does not unduly increase the shedding of non-waste products at the same time (in particular water and sodium) because secretion of excessive amounts of these essential elements brings its own problems, as you might expect. Felodipine works on the general venous system. One of its known side effects is swollen ankles (dropsy). There is a tendency in some people to have excessively constricted veins. A manifestation of this is known as Raynaud’s syndrome, where (typically) the ends of the fingers and toes go white due to subnormal blood flow. Felodipine is sometimes used to treat this condition, but for those of you who like simple cheap cures, if you get this problem, simply whirl your extended arm around as fast as you can for about twenty spins and your fingers will be a lovely rosy pink again - like magic. (Warning- when whirling your arm around, check clearances to table edges and other obstructions or you will have other reasons for consulting a physician).
How you achieve the same result for your toes is not quite so straightforward – maybe regular sessions on that Octopus whirly gig at the local Fair might do the trick.
Caffeine is a known vasoconstrictor, but not to the extent that you should immediately forgo its other (beneficial) effects.


High Blood Pressure

The author was first diagnosed with elevated blood pressure at 260/160 which is days away from a stroke. It is now around 140/85 almost all the time and kept in check by taking one of each tablet first thing in the morning.


A very short course on blood pressure.   The first number represents the maximum (systolic) pressure reached (the units are mm of mercury, for those who know their meteorology) when the heart ejects
blood into the aorta.  The second number is the steady state (diastolic) pressure in the system and is a measure of how hard you have to squeeze on the circulatory system to prevent any blood from
flowing at all.  It is believed (there is no objective scientific proof) that diastolic pressure should not be over 100 under normal conditions, and the systolic should not exceed around 140.
Women and children usually have lower blood pressure levels than these. In almost every individual case blood pressure rises with age, probably due to the progressive loss of elasticity of the blood vessels.

While low blood pressure is “good” in that it is believed to lessen your risk of heart failure and stroke, very low blood pressure is not “good”. Hypotension, which is admittedly much less common than its opposite, can cause you to die by making you lose consciousness when you stand up after stooping down so that you fall under the approaching bus. This point is made simply to warn anyone taking blood pressure reducing medication that elimination of your blood pressure is not the goal, just its reduction. (in Greece Hypo means something like the opposite of Hyper).

Aspirin (salycilic acid) is also believed to be beneficial in reducing the risk of congestive heart failure, because it has an anti-coagulant effect on the blood (makes it thinner, therefore easier to pump). Warferin (vitamin K) is even better, but some people baulk at swallowing rat poison. This same, or an analogous argument, is advanced in favour of Marijuana, and when the drug companies finally take control of its production and supply, we will all miraculously be encouraged to have a daily dose.

Beta blockers, on the other hand, have the effect of limiting your physical output by preventing your heart from beating any faster than about 90. This is almost exactly like having a governor fitted to you, and clearly if there is a real risk of heart failure if your pulse rate goes up then this medication is probably necessary. If, however, you are otherwise healthy but simply have this tendency to elevated blood pressure, then beta blockers are a dumb idea, because they limit your enjoyment of life, especially if you enjoy physical activities. Some men on these things become impotent (and then they gulp down Viagra to counteract that, and end up like an automatic car being driven by someone with a foot hard on the brake and the other one hard on the gas, with the inevitable outcome). And clinical depression is not unknown (clinical is a Greek word meaning bed), owing to the chronic lethargy that goes with them. Apparently the impact they have on people varies a lot. They do not treat the symptom (high blood pressure), and some people who take them still suffer from high blood pressure because (possibly) the hormonal system tries to compensate for the limited stroke rate by increasing the stroke volume. This can lead to a condition called ventricular hypertrophy which is Greek for swollen heart chambers, and the big trouble with that is that the circulatory and pulmonary (lung) systems get out of whack, and then you die or have a heart transplant and die a little later on.

Of course nobody has the faintest idea what the really long term effects of all these drugs are, but come the revolution, all of us old bastards are going to be shot anyway.

You should get some competent advice before you change what you are doing, but do not assume that your GP knows more than diddley squat about all this - they just follow whatever instructions they get from the drug companies, either directly, or via the sinecured professor of cardiology who gets a new Merc and a round-the-world trip every year for taking a sensible approach to recommending their products.

Tips

Get a little electronic BP monitor. Measure your BP once per week, preferably at the same time and in the same circumstances- e.g. just after breakfast, and certainly at the same time relative to any medication you are on. Some models have an averaging calculation which will show you a trend over a month.

And here is some really cheap medication you can try, for which you need nobody’s permission, no tests, and no monitoring. Every morning, after you get out of bed, but before you do anything else, drink as large a glass of water as you can get down. Cold water, no additives. Do this every day without fail. The water may have the desired effect. It does not work on everyone, but the mechanism is that there are little sensors in the glomeruli (remember them?) in the kidneys and they detect how much toxic material is around, and if they don’t have enough fluid to flush it all out they signal for more tap pressure, with the result we all know. Swallowing clean water with no electrolytes in it is believed to have some way of reaching the kidneys by some pathway other than the bloodstream - capillary action or osmosis or something. If this pathway is available, the glomeruli in the kidneys will stop telling the adrenal gland to secrete the AC enzyme.

This sound idea is not promoted by most of the medical profession because it is far too low-tech, and there is very little money to be made from it. To be a bit fair on the poor old doctor, you can pretty much imagine the reaction of someone who has driven the Porsche Cayenne up to the surgery expecting a pharmacopoeia of the greatest wonder drugs since penicillin, only to be told to go away and drink several glasses of clean water every day! The poor old doc would be dragged in front of a panel, charged with disgraceful conduct and drummed out of town. The reason why the glomeruli misbehave is not really well known (causes are far harder to come by than symptoms) - one theory is that there are many cases of undiagnosed kidney disease in early life that damages the feedback system in some way (even strep throat can damage the kidneys). Another is that the damage is caused by toxins in the food supply, and the third (and the one most beloved of the medical industry) is that some people have a genetic predisposition to hypertension and need to take drugs all their lives to combat it.

And here is a bit more advice, for which you should really pay me, because it will save you a lot of money. Eat less but better, and drink less (alcohol). The epidemiologists (who are doctors who don’t like dealing directly with patients and who found that they like statistics) are more or less agreed that a typical middle class New Zealander gets around 30% of their calorie intake from a substance whose formula can be expressed in the form C2H5OH- ethyl alcohol, or booze. This is because the epidemiologists have extrapolated the data recorded by doctors and insurance companies in response to “How much do you drink?”, and compared that with the actual amount of alcohol purchased from the excise tax data, and concluded that people being asked how much they drink either lie, or they pour half to two thirds of what they buy straight down the drain. What do you do?

So halve what you drink and you reduce your calories by maybe 15%. Your weight will come down and your wealth will go up. Each of which is known to have a very beneficial effect on blood pressure.

Have a great life.