High blood pressure affects one in three adults in France. Objective of anti-hypertensive treatments: to control blood pressure in order to protect against cardiovascular diseases, including stroke. Indications, contraindications, effectiveness of these drugs … Update with Professor Xavier Girerd, cardiologist.
What is an anti-hypertensive agent?
Anti-hypertensive drugs are a group of drugs used to normalize high blood pressure . Antihypertensives have a wide variety of mechanisms of action and belong to five families of drugs: diuretics , beta blockers , calcium channel blockers, converting enzyme inhibitors (ACEIs), angiotensin II antagonists ( ARA-II) or also called sartans . The treatment should be followed for the long term. Regular blood pressure monitoring is necessary to check the effectiveness of the treatment.
What are the indications?
“The indication for treatment is defined when the self-measurement of blood pressure shows systolic blood pressure figures greater than 135 and / or diastolic blood pressure figures greater than 85 “, says Professor Xavier Girerd, cardiologist at Pitié-Salpêtrière and President of the Arterial Hypertension Research Foundation.
→ Systolic blood pressure corresponds to the pressure in the arteries when the heart contracts, diastolic to the pressure in the arteries between two heartbeats.
In order to best measure this tension, experts advocate self-measurement: the patient himself measures his blood pressure using an automatic blood pressure monitor, a device which is however not reimbursed by Social Security. In order to achieve a reliable self-measurement, the Haute Autorité de Santé (HAS) recommends three measurements at one-minute intervals, morning and evening, over three consecutive days, i.e. 18 measurements in total. ” Before offering a drug treatment to a patient who suffers from hypertension, we will first lower his salt intake. In the context of excessive consumption, the tension rises quickly in the hours following the meal. However, within 24 hours, 80% of this salt is eliminated in the urine.Treatment generally begins with nutritional measures, and this for only 8 days , the effects must be immediate. “ After these eight days, if the blood pressure is still so high, a drug anti-hypertensive treatment is then implemented.
Automatic pressure measurement: when to perform ABPM?
ABPM is the Automatic Measurement of Blood Pressure (ABPM) at home. Also called a blood pressure holter, it can be offered when a doctor wishes to measure the blood pressure of a patient throughout the day and be useful in making the diagnosis of arterial hypertension and adapting the treatment.
What are antihypertensive drugs?
“The effectiveness of drugs vary depending on the patient, depending on their level of blood pressure and their own physio-pharmacological characteristics ,” our expert asks upstream. There are five classes of antihypertensive drugs. High blood pressure being a disease which constricts the arteries, these drugs act according to their properties, on the relaxation of the arteries.
- Thiazide diuretics: these are the oldest anti-hypertensive drugs. They promote the elimination of water and salt by the kidneys and thus reduce the volume of fluid that circulates in the arteries. This action decreases the tension on the artery walls. Currently, they are used at low dosages which limit their side effects. Regular monitoring of their effect on the kidneys should be done by blood test.
- Beta-blockers : “ These drugs treat high blood pressure but also angina, heart failure and heart rhythm disturbances “, comments Xavier Girerd. They block the action of adrenaline and norepinephrine and decrease the secretion of renin, hormones that cause blood pressure to rise. Beta blockers by attaching to receptors block the effect of these substances which causes the drop in blood pressure.
- Calcium channel blockers : “These drugs oppose the release of intracellular calcium responsible for the contraction of the arteries. Thus, they promote the relaxation of the arteries, a primary cause in the rise in blood pressure. These drugs work in almost all hypertensive patients “, develops the cardiologist.
- Converting EnzymeInhibitors (ACEIs) : These drugs block the production of angiotensin II, a hormone that increases blood pressure. “ IECs have been a real revolution in cardiology. They treat two major diseases, high blood pressure and heart failure, ” adds Xavier Girerd.
- Sartansor angiotensin receptor antagonists (ARA-2) block the action of angiotensin II. “ These drugs are very effective antihypertensive drugs and have a protective action on the kidneys, particularly in diabetes . They have no specific side effects and their combination with a diuretic or a calcium channel blocker increases their effect on the blood. They are available in France in several ‘fixed combinations’. In France, these are the drugs most often found on prescriptions for hypertensive
In the majority of patients, high blood pressure will not be controlled with just one medication . “The doctor suggests a drug. At the end of four weeks, if the treatment does not bring the expected effectiveness, a second drug is added. We can add a third, to obtain control of the blood pressure,” explains our expert. .
What are the values to reach to evoke controlled blood pressure?
130 for systolic blood pressure and 80 for diastolic blood pressure when blood pressure is measured at home by self-measurement (or “13/8″). ” After four weeks of treatment, about 30% to 50% of patients are controlled with a single drug . For the others, two drugs are given. It is noted that 80% of hypertensive patients are usually controlled by regular monitoring of one or two anti-hypertensive drugs, ” specifies Xavier Girerd. In order to make life easier for patients, there are now drugs that contain two molecules. These are called the fixed combinations of antihypertensive drugs . “A third of the drugs prescribed in France are drugs that contain two active ingredients, “adds the specialist in hypertension.
What are the side effects of antihypertensive drugs?
“All these antihypertensive drugs have a long list of side effects mentioned on the information sheet! However, these effects do not occur in the majority of patients, they are benign and disappear always stopping the medication. It takes be reassured because anti-hypertensive drugs, which are old drugs, are very well known and no bad surprises are likely to occur when they are prescribed “, says the cardiologist. Edema, cough, pseudo-dizziness shortness of breath, low potassium ,Bradycardia, fatigue … The list may seem long but the doctor will know how to adapt a treatment in the event of a side effect. Several options are possible, including reducing the dosage, changing the drug class or adding another antihypertensive drug. By drug class, the most notable side effects are:
- Diuretics : ” These drugs affect the results of the blood test. They can indeed cause a drop in sodium and / or a drop in potassium in the blood”, notes Professor Girerd. Thus, too low a sodium level (hyponatremia) in the blood can lead to confusion, lethargy, depression, coma for the most serious cases. This disorder is favored by too many drinks (water, soda) per day and by taking other drugs such as antidepressants from the IRS family. Too great a drop in the level of potassium in the blood can cause cramps, cardiac arrhythmias and very rarely muscle paralysis. Thiazide diuretics and anti-aldosterone drugs can sometimes be the cause of erectile dysfunction or breast pain.
- Beta-blockers : ” These drugs have powerful cardiological and pulmonary effects which are sometimes considered undesirable. They cause a slowdown in the heart rate (bradycardia, editor’s note) which, if too severe, can cause shortness of breath and fatigue which at most will be accompanied by discomfort by syncope Sometimes asthma can be triggered by treatment“. Not all beta-blocker drugs have these same side effects and it is always suggested to decrease the dosage or change the molecule before deciding to stop the drug. Beta-blockers have a bad reputation for causing blood disorders. erection, but “blind” studies have shown this effect to be less common than when prescribing diuretics.
- Calcium antagonists: “They are generally well tolerated but 20% of patients will have edema of the lower limbs favored by the heat and the standing position. This benign side effect if it is too troublesome will lead to the reduction of the dosage and / or the stopping treatment “, comments our expert.
- ACE inhibitors: ” The most common side effect is a dry cough accompanied by itching of the throat. This cough can occur a few days or weeks after the start of treatment. About 20% of patients have this symptom, which requires a replacement of the treatment. More rarely certain patients (smokers, black people) have a risk of developing angioedema of the lips or the tongue which can be complicated by angioedema “.
The intake of non-steroidal anti-inflammatory drugs and corticosteroids should be monitored if the patient is on anti-hypertensive drugs.
- ARBs (sartans)do not cause specific side effects and their side effect profile is comparable to that of placebo. As they reduce the side effects of other antihypertensive drugs, they are frequently prescribed in combination which makes it possible to reduce the frequency of the drop in potassium (with a diuretic) and edema of the lower limbs (with a calcium antagonist)
What are the precautions for use?
The intake of non-steroidal anti-inflammatory drugs and corticosteroids should be monitored if the patient is on an anti-hypertensive drug. These drugs can indeed be responsible for an imbalance in hypertension. ” This imbalance only lasts as long as the treatment is taken. In this case, a drug can be added to regain control of the hypertension .” Not all patients who are treated for hypertension have their blood pressure imbalanced when taking an anti-inflammatory drug. This will involve monitoring his hypertension by self-measurement. Sartans and ACE inhibitors cannot be prescribed to a pregnant woman from the second trimester of pregnancy . If a woman is already on treatment when she becomes pregnant, “it is then advisable to change the treatment “, notes the cardiologist, by prescribing other anti-hypertensive drugs. Note that when hypertension occurs during pregnancy, in the second and third semester most often, it is then most often due to poor vascularization of the placenta “. It is pre-eclampsia, a complication of pregnancy responsible for fetal distress and high blood pressure in the mother. ” We now know that drug treatment will not have positive consequences for the fetus “. A cesarean section is scheduled as soon as possible, at a term that is safe for the fetus.
How long before an antihypertensive drug works?
Anti-hypertensive drugs do not work immediately. It is imperative that the patient follows his treatment well to see the first effects of the drugs on his blood pressure, ” between 4 and 10 days on average” , depending on the therapeutic families of the drugs. And if during this adaptation time, the patient notices too low a voltage during a self-measurement session, “it is therefore advisable to seek medical advice to adapt the dosage of the drug after monitoring the blood pressure over several days. In general, the patient should not decide to take the drug according to the value of a blood pressure measured on a single occasion and it is the blood pressure taken over several days that allows the doctor to give advice concerning the continuation or the interruption of anti-hypertensive drugs “, adds Xavier Girerd.
What are natural hypertensives?
The most important thing is to avoid excessive salt intake and to enrich your diet with potassium from food . If the World Health Organization recommends not to absorb more than 5 grams of salt per day for an adult, in practice, in France, a normally salty diet contains less than 10 g of salt per day. The first effective way to lower your blood pressure is to reduce excessive consumption of foods that contain hidden salt . “ In a normal diet, we absorb between 6 and 10 grams of salt per day, comments Xavier Girerd. More than twelve grams per day can cause a significant increase in blood pressure and should be avoided in hypertensive patients.We do not recommend that hypertensive people eat without salt, but to reduce foods rich in salt . “ In addition, for about twenty years, hypertensive people have been advised to enrich their diet with dietary potassium by increasing the daily amount of sodium . fruits, vegetables and seeds . ” The DASH diet (for Dietary Approach to Stop Hypertension or, in French, the Dietary Approach to Stop Hypertension) has shown some efficacy on blood pressure, particularly if it is associated with a limitation salt intake “indicates Pr Girerd.” The DASH dietevaluated on North American populations has been shown to be most effective in African American women and least effective in white men, “he says.
