Antihypertensives

None of the 66 pharmaceutical drugs currently licensed as treatment for high blood pressure, or hypertension are any better than ‘water pills’ according to the new breakthrough study. This means that doctors will need to seek out alternatives to treat one of the most common medical conditions in the West.

This damning conclusion also throws into doubt the effectiveness of many of the most financially lucrative types of drugs on the market to-day, including alpha-blockers, beta-blockers, calcium channel blockers (or calcium antagonists) angiotensin-11 receptor blockers and angiotensin-converting enzyme (ACE) inhibitors. Each of these drug types includes a number of competing products from different manufacturers.

This remarkable expose of this set of the ‘Emperor’s new clothes’ has come from Australian mathematician Thomas Lumley. Who has developed a new kind of medical analysis. Indeed the American Medical Association has been so impressed by his analytical methodology that it has published his findings in its own prestigious journal (JAMA, 2003: 289;2534-44). This man prove to be a brave watershed gesture for a peer-reviewed journal that has enjoyed enormous streams of revenue from drug-company advertising, and has itself, in the past, often championed one of the very anti-hypertensive drugs condemned in Lumley’s report.

Although still only in his 30s Lumley has developed a whole new way of analyzing medical data from clinical trials. It’s a breakthrough in statistical analysis that enables results from very differently designed medical trials to be pooled, thus allowing the maximum amount of information to be extracted. Until now, the normal way of pooling medical-trial date has been by what’s called meta-analysis. This was a method proposed in 1976 by Gene Glass, now a professor at the College of Education at Arizona State University, to integrate and summarise the findings from a body of research.

“Meta-analysis refers to the analysis of analyses.   I use it to refer to the statistical analysis of a large collection of results from individual studies for the purpose of integrating the findings,” said Glass. But the technique is limited as it cannot easily distill information from drug trials that have been set up for different purposes.   For example, new drugs may be tested against a placebo or they may be compared with existing drugs.   But the two types of trials are, statistically speaking, apples and oranges and so not truly comparable.

Any stress is an indication that we need to increase our vitamin B complex intake.  Sufficient B-complex helps to normalise oestrogen levels.  On the other hand, an increase in oestrogen can cause symptoms of vitamin B deficiency.   An example of this effect can be seen in the use of oestrogen-based birth control pills use of which results in deficiencies in vitamins B6, B12 and folic acid.

Lumleys new technique which he calls ‘network meta-analysis- is a way of linking the date from all drug trials, whatever their purpose, so that a clear picture emerges from what has hitherto been a statistical fog. Lumley’s network meta-analysis is tailor-made for to-day’s drug dependent conventional medicine, and the internecine competition among dozens of different drugs for the same medical condition.

Anti-hypertensives are a highly profitable group of drugs-largely because the condition of high blood pressure is considered to require constant pharmaceutical management.   As a result, many people are given anti-hypertensive drugs for years on end, making these products the most commonly prescribed medications in the world. Over the years, as their original product patents have begun to expire, drug manufacturers have brought out newer drugs with different modes of action and of course, higher price tags. Drug companies have also waged a successful behind-the-scenes campaign to make more of us officially victims of hypertension and this, potential drug recipients.

The US official health organisation the National Institutes of Health (NIH) recently revised its definition of high blood pressure downwards. Until earlier this year a blood pressure reading of 130/85mmHg (systolic/diastolic, respectively) was considered normal.   But now the acceptably normal systolic figure is 120mmHg.  Any one with a blood pressure that is above that figure is now considered ‘prehypertensive’ – a new category of blood pressure patient.

Full-blown hypertension is said to begin at a systolic level of 140mmHg (the diastolic blood pressure is now thought to be relatively unimportant). The upshot is that the developed countries are spending billions of pounds and dollars a year on anti-hypertensive drugs.  But is it all necessary?  Network meta-analysis says ‘no’.  Even accepting the premise that high blood pressure needs to be treated with drugs.

What Is Hypertension?

Hypertension (high blood pressure) is not a ‘disease’ per se, it is believed to be a significant risk factor in other diseases, including heart attack ,.heart failure, stroke and kidney disease.  Once called ‘the silent killer’the UK medical authorities reckon that 25 per cent of us suffer from hypertension and that it causes over a third of all deaths in people under 65. How do you get high blood pressure? For most there is no definite cause, although it appears to be related to diet and lifestyle. However some hypertension has a known cause, including pre-eclampsia, congenital heart defects, or problems with the kidneys or adrenal glands. This is called ‘secondary hypertension’ and accounts for 10 per cent of cases. Other causes of secondary hypertension are prescribed drugs such as cyclosporin, oral contraceptives, hydrocortisone, non-steroidal anti-inflammatory drugs (NSAIDs) and tricyclic antidepressants.

A major risk factor for essential hypertension is age.   Blood pressure tends to gradually rise the older we get.   Doctors used to think that this was normal and used a rule of thumb that 100 plus a person’s age was an acceptable upper limit for blood pressure. So a systolic pressure of 160 mmHg was acceptable for a 60 year old.  However this is now considered outdated and all of us are encouraged to reduce our systolic levels to 120 mmHg, whatever our age.  Nevertheless, this recommendation may be tied to the vast number of antihypertensive drugs on the marked, and is not universally accepted by doctors.   “All these new guidelines essentially accomplish is to convert 45 million healthy Americans into new patients – by creating fear” says Dr. Paul J. Rosch, clinical professor of medicine at New York Medical College.

What Are Diuretics?

Diuretics were invented 70 years ago to reduce body swelling due to water retention.  They are based on relatively simple chemical formulas that work by encouraging the kidneys to expel more urine, thereby reducing the amount of water in the body.   Thus, diuretics are popularly known as ‘water pills’. Commonly prescribed diuretics are bendrofluazine, chloronthiazide, chlorthlidone, and idapamide.  That diuretics lower blood pressure was discovered by accident in the 1940s and even today it is not known how they work to reduce blood pressure.

It is claimed that diuretics prevent the cardiovascular illness caused by high blood pressure, such as stroke and heart failure, but the actual reduction in death rates appears to be only a modest 10 per cent.  The picture is further complicated by two recent pieces of evidence.

  • Low blood pressure as well as high blood pressure can lead to cardiovascular problems and premature death-and one cause of low blood pressure is diuretic drugs.
  • Diuretics can have serious side effects such as cancer of the kidneys, which may further worsen death rates.
  • Other side effects include impotence, dizziness on standing up, due to low blood pressure, blood disorders, skin reactions, gout pancreatitis and depletion of potassium magnesium coenzyme Q10 and zinc.

Measuring Blood Pressure

Having no symptoms, hypertension can only be diagnosed by measuring it.  Two readings are taken, the pressure of the blood when pumping (systolic) and the resting pressure between each heartbeat (diastolic).  The numbers refer to the height of a column that the pressure can sustain, measured in millimeters of mercury (mmHg).  Although it is a routine medical procedure, blood pressure measurement is not nearly as reliable as doctors often make out.

First BP readings can vary widely and yet still be normal.   BP will rise with physical exertion, or stress of any kind, however minor.   The time of day, room temperature, a full bladder, eating drinking or smoking within the previous hour, standing sitting or lying down can all influence BP measurements.   Even having a conversation increases BP and if the person being spoken to is of higher social status blood pressure may rise as much as 50 per cent.  This helps to explain what has been dubbed ‘white-coat hypertension’ – a rise in blood pressure caused by the very act of having BP measured by a doctor.  In fact it has been estimated that as many as one in five people diagnosed as hypertensive are receiving unnecessary drugs because of white-coat hypertension.

Alternatives To Drug Treatment

There are literally scores of ways to reduce high blood pressure without having to take recourse to drugs. The high incidence of hypertension in the West and its virtual absence in many developing countries is thought to be mainly due to diet.   Meat appears to be a major culprit in a recent Oxford University survey, meat eaters had an average of 4 mmHg higher blood pressure than vegans. 9Public Health Nutr,2002;5:645-54)  The US recently launched a campaign using a diet called DASH (Dietary Approaches to Stop Hypertension) to reduce BP.   It is high in fruits, nuts and vegetables and emphasizes fish and chicken rather than red meat, and is low in saturated fats and refined carbohydrates.   Tested against a diet high in fruit and vegetables, the DASH diet was slightly better, with an average overall BP decrease of 5mmHg and a staggering 11mmHg drop in hypertensives.

The result is as good as or even better than what many drugs offer, leading researchers to recommend the DASH diet as a first-line treatment for hypertension.  This is yet another example of the medical establishment belatedly accepting what healthfood campaigners have been advocating for decades. The only controversial aspect of the DASH diet is salt, which has long been thought to play a major role in high blood pressure, though doctors seem to be having a hard time proving it.  Some studies show that it causes hypertension but must don’t.  The bottom line is that there is no evidence that reducing either salt or sodium helps people to live longer.

Other minerals, however, are important.   People with hypertension are consistently being found to be lacking in magnesium and diets naturally high in magnesium, potassium and calcium are known to reduce BP substantially.   So, should people with hypertension take magnesium supplements?   A 20 year old study believes they should having discovered that magnesium supplements lowered BP by 12 mmHg But the latest evidence is not as convincing.   Nevertheless magnesium supplements are recommended for anyone with a magnesium deficiency or who is taking diuretics. It is also known that a diet high in sugar impedes potassium uptake and BP usually decreases when sugar is excluded.

Higher dietary fibre can also lower BP.   When more than 30 people switched to a diet of mostly raw high-fibre foods for six months their diastolic BP plummeted by an impressive 18 mmHg. But there is an easier way to achieve nearly the same dramatic reductions – take vitamin C,.  Dr, Balz  Frei and colleagues at the Linus Pauling Institute recently tested 45 people with moderate-to-severe hypertension (average 155/87 mmHg in a double-blind placebo-controlled trial.

Patients took either 500 mg/day of vitamin C or a placebo.   After a month BP dropped by 9 per cent with vitamin C, bringing their average BP down to 142/79 mmHg.  However vitamin C did not reduce BP in those whose BP was n the normal range- unlike diuretics which can reduce BP to dangerously low levels.  How does vitamin C do this?  We are not sure of the mechanism says Frei.   One theory is that the antioxidant properties of vitamin C protect the body’s  level of nitric oxide, a natural compound which relaxes blood vessels and helps maintain a normal healthy blood pressure (Lancet, 1999; 345:2048-9.

Another possible antihypertensive micronutrient is vitamin B.  There is mounting evidence that homocysteins is a major factor in cardiovascular disease.  This naturally occurring amino acid is thought to indirectly cause atherosclerosis (fatty deposits in the arteries) and hypertension.   Two key discoveries have been made in the lab: high homocysteine (above 12 mmol/L0 is related to low blood levels of vitamin B ; and B vitamins can detoxify homocysteine.  The recommended dose is vitamin B as folic acid (800mcg/day) plus B6 and B12 in a daily multivitamin.

Coenzyme Q10 is another naturally occurring enzyme with dramatic effects on .hypertension. This was first discovered in the 1950s by US nutritionists, who detected this antioxidant deep within body cells and found that it played a vital role in converting nutrients into energy.   Japanese doctors were the first to take up the new nutrient supplement and found it to greatly benefit heart patients, reporting significant improvements in 75 per cent of cases of congestive heart failure, angina and hypertension.

In 1985 a group of American doctors at the University of Texas began giving CoQ10 to their hypertensive patients.   Eight years and more than 400 patients later, they announced their astonishing results.   A daily dose of 75-600 mg of CoQ10 had improved hypertension to such an extent that within six months 97 per cent of these patients could stop taking their conventional drugs.

However, it was only recently that the truly extraordinary value of CoQ10 has been acknowledged. Two years ago US government doctors mounted a full-scale randomized placebo-controlled trial where they gave 80 hypertensive patients 60mg of CoQ10 twice a day for 12 weeks.   Systolic BP reduced by 18mmHg with no side effects.  CoQ10 may be safely offered to hypertensive patients as an alternative treatment option they concluded.  But alternative to what?  Certainly not to prescription drugs which are generally hard put to achieve such a degree of reduction and only with the added penalty of a whole raft of side-effects.