High blood pressure (hypertension) affects approximately 25% of the world population and its prevalence is expected to increase by 60% by 2025, an estimated 1.5 billion people affected in total. Hypertension is a major cardiovascular risk factor and is responsible for most deaths in the world. The essential or idiopathic hypertension is responsible for at least 95% of cases of hypertension. Many causes, endocrine, vascular, renal, reflect the 5% of secondary hypertension.
In a patient with hypertension, the doctor will diagnose hypertension, assess the severity and impact and for the cause. The questions that any doctor who supports a hypertensive patient must meet are presented in Box 1.
Box 1. Questions to ask for the support of a hypertensive patient
How to diagnose an ongoing HTA?
What is the balance needed to be expected?
When to start treatment?
What are the treatment goals?
What are the therapeutic methods?
What to treatment?
When referral to a specialist?
DIAGNOSIS:
Systolic and diastolic hypertension were both recognized as cardiovascular risk factors as associated with increased cardiovascular morbidity and mortality in large observational studies. They face a risk of stroke, heart failure, peripheral arterial disease and ESRD independently. This is why high blood pressure is considered the leading cause of death worldwide.
Definition:
There is an ongoing relationship between the degree of hypertension and cardiovascular risk, from 110-115 mmHg systolic and figures for 70-75 mmHg diastolic.The thresholds used to classify the severity of hypertension are arbitrary but allow in the daily practice of simplifying its diagnosis and therapeutic management.
Hypertension is divided into grades according to its level (Table I).
Measurements of blood pressure:
Blood pressure (BP) is characterized by large spontaneous variations during the day and from one day to the next.Its diagnosis should only be selected after several measurements at different times over a period of time. The diagnosis of hypertension should be based on at least two measurements per visit in two or three consultations.
The interval between consultations may be sooner or later depending on the PA figures measured. Several types that can be used.
AP consultation:
One patient in the sitting position for several minutes, the PA will be measured twice 1-2 minutes apart and a third if the first two are very different. The cuff should be tailored to the patient’s arm (obese child), wrist at heart level. Heart rate should be noted.
Ambulatory BP measurement or ABPM:
It consists of PA repeated doses for 24 hours in a patient leading a normal activity. It can not replace the power plug from the consultation but provides additional information: Measuring the most reliable PA, freeing the blouseblanche effect and the placebo effect, patient screening lacking the physiological decline PA overnight (non-dippers) that have a higher prevalence of organ damage and a worse prognosis than those with lower PA overnight.
Self-measurement of blood pressure:
This measurement method does not provide as much information as ABPM but it comes close. It is also devoid of the effect of “white coat,” or placebo. It is more reproducible and best predicts cardiovascular risk that measures the firm.
The patient should be advised to use validated measurement systems and keep the arm at heart level.
Categories of patients:
These different methods of measurement used to identify several categories of patients.
HTA “, white coat”:
This hypertension is diagnosed the doctor’s office while automesures at home or at a MAPA are normal. This type of hypertension is present in 15% of the population.
Cardiovascular risk of these patients is intermediate between that of constantly hypertensive patients – in cabinet and at the ambulatory – and normotensive patients.
Isolated ambulatory hypertension or hypertension “masked”:
The reverse is also in normotensive individuals consultation (<140/90 mmHg) with ambulatory pressures or high self-measurement. The data available suggest that the cardiovascular risk associated with hypertension “hidden” is close to that of permanent hypertension.
The different BP measurements provide useful information especially when there is no apparent hypertension in consultation in patients with multiple cardiovascular risk factors.
HTA effort:
All types of stress, physical or psychological, increase the PA and individual stress response was evaluated as a risk for the development of a permanent hypertension and cardiovascular risk factor. The results are contradictory and the decision to initiate treatment can not be based solely on the stress-related hypertension.
Review:
Personal and family history:
The personal and family history should be sought broadly with particular attention to the associated cardiovascular risk factors.
The history should look for:
– The duration and degree of hypertension found figures;
– Symptoms suggestive of secondary hypertension;
– The treatments used and their effectiveness, taking treatments (corticosteroids, anti-inflammatory drugs, nasal vasoconstrictors, oral contraception, erythropoietin, cyclosporine) or drugs (amphetamines, cocaine, alcohol);
– Lifestyle (salt and fat diet), smoking, physical activity;
– History or coronary symptoms of heart failure, diabetes, peripheral or cerebral vascular disease, gout, asthma and all drugs used to treat these diseases;
– The presence of a nocturnal snoring suggesting a sleep apnea syndrome.
Clinical examination:
The heart rate should be noted at the same time that the PA. Repeated acceleration of heart rate may indicate an increased risk through increased sympathetic activity, decreased parasympathetic or heart failure.
The body mass index tracks obese (> 27).
The measurement of waist circumference in a patient standing indicates the type of obesity and increased risk if gynoid morphotype.
Palpation of the abdomen search polycystic kidney disease by the presence of a lumbar contact. Palpation of the pulse search coarctation of the aorta. Auscultation Research abdominal breath that can be evidence of renal artery stenosis.
Additional tests:
They look for risk factors, the arguments in favor of secondary hypertension, and aim to assess the impact of hypertension.
Examinations must go from simple to more complicated. More young patients, severe hypertension and acute onset, more examinations must be thorough. The minimum requirement is shown in Table II.
Emphasize some important points:
1. A fasting glucose greater than 5.6 mmol / L warrants a glucose tolerance test in search of diabetes.
2. The values are imprecise creatinine to estimate kidney function and must be supplemented by the calculation of creatinine clearance by the Cockcroft and Gault or glomerular filtration rate (GFR) estimated by abbreviated MDRD formula, for identifying patients with reduced glomerular filtration and increased cardiovascular risk despite normal serum creatinine values.
The MDRD formula classifies renal failure in stage 3 (GFR <60 mL / min / 1.73 m2), 4 (GFR <30 mL / min / 1.73 m2) or 5 (GFR <15 mL / min / 1.73 m2). It is more reliable for values of GFR <60 mL / min / 1.73 m 2 as the Cockcroft. The discovery of compromised renal function in hypertensive patients is frequent and is a powerful prognostic factor for cardiovascular events and death even in treated patients.
3. Microalbuminuria is closely associated with an increased incidence of cardiovascular disease not only in diabetes but also in non-diabetics.
4. The unfavorable prognostic role of concentric left ventricular hypertrophy has been confirmed as the thickness of the carotid intima.
Without ultrasound assessment, nearly 50% of hypertensive patients may be considered erroneously as low or moderate risk, whereas the presence of these vascular anomalies class in a high risk group.
5. The electrocardiogram should be part of the routine evaluation of hypertensive subjects. Its sensitivity is low, but left ventricular hypertrophy detected by the Sokolow-Lyons index (SV1 + RV5-6> 38 mm) is an independent predictor of cardiovascular events.
6. The fundus is not recommended as first-line, severe retinal lesions, grade 3 (bleeding and exudates) and 4 (papilledema) are only correlated with systemic impact.
7. The MRI allows the discovery of silent brain infarction, usually limited and deep (lacunar). The prevalence of lesions increased with age and hypertension. MRI can be recommended for all hypertensive patients for reasons of cost and availability, but it should be reserved for patients with neurological abnormalities.
TREATMENT:
Start of treatment:
Current recommendations emphasize the need to include the decision of hypertension and treatment modalities in the broader context of the management of absolute cardiovascular risk. This risk is determined, although the level of PA, but yet by the associated vascular risk factors.
The assessment of absolute cardiovascular risk affects not only the blood pressure threshold setting of drug treatment road, but also the blood pressure goal and, somehow, rigorous monitoring and the means used to achieve it .
Box 2 and Table III can help make the decision.
Box 2. Data included in the estimation of cardiovascular risk
Cardiovascular risk cofactors
Age: men> 50 years; Women> 60 years
Smoking
Early familial cardiovascular event
Diabetes
Dyslipidemia
LDL> 4.1 mM or HDL <1 mM
Attainment target organs
Left ventricular hypertrophy
Microalbuminuria: 30-300 mg / day (20-30 mg / mmol creatinine)
Comorbidity
GFR <60 mL / min or protein> 500 mg / d
Transient ischemic attack or stroke
Coronary artery disease
Peripheral arterial disease
Basically two categories can be defined as:
– High or very high risk patients: It is recommended to start medication immediately (immediately or after a few days of observation);
– Medium or low risk patients: It is advisable to offer lifestyle measures alone initially. The decision to involve an antihypertensive drug is reassessed at 3, 6, 12 months depending on the evolution of blood pressure and other risk factors.
Therapeutic targets:
In the general population:
Any patient with permanent hypertension (defined as systolic BP ≥ 140 mmHg and / or diastolic BP ≥ 90 mmHg) should benefit from the initiation of lifestyle measures and sometimes prescription of antihypertensive medication.
In diabetic or at high cardiovascular risk patients:
To maximize cardiovascular protection in diabetic patients, the reduction of hypertension objectives are stricter, less than 130/80 mmHg as associated with a net profit on micro and macrovascular complications.
In non-diabetic patients but high-risk (history of stroke or heart attack), a decrease of PA 147/86 mmHg to 138/82 to allow a 28% reduction in stroke recurrence and 26% of major cardiovascular events in secondary prevention. There are insufficient data to recommend a decrease of PA below 130/80 mmHg in non-diabetic patients currently.
Therapies:
These are lifestyle measures and antihypertensive drugs.
Lifestyle measures:
Essential in all cases even if the benefit in primary cardiovascular prevention of lowering blood pressure following their application is not formally demonstrated (no controlled trial).
The goal is to decrease the level of the PA, to correct any risk factors and reduce the number and doses of antihypertensive treatment. The effects of the measures adopted are given in Table IV.
Weight loss in obese patients leads to improved associated risk factors such as insulin resistance, diabetes and hyperlipidemia, left ventricular hypertrophy and sleep apnea.
The restriction soda – easily quantified by natriuresis – 180 mmol (10.5 g NaCl) 80-100 mmol (5-6 g) per day 5 mmHg lowers the PA and lighten treatment. This effect is more pronounced among black subjects, aged, diabetes and renal impairment. The objective is to achieve reasonable 5 g salt per day.
The increase in potassium intake and low cholesterol diet can reduce hypertension. Hypertensive patients should eat more fruits and vegetables, more fish and less saturated fat and cholesterol.
Exercise reduces excess weight, waist circumference and increased insulin sensitivity and HDL-cholesterol.Physical exercise even moderate endurance (brisk walking, jogging, swimming), in the absence of severe hypertension or cardiovascular complications, helps to reduce the PA.
Place antiplatelet agents:
The addition of low-dose aspirin (75-100 mg / day) reduces the risk of serious vascular events by 25%, the price of a risk of severe bleeding doubled. The decision to add an antiplatelet therapy must be taken depending on the overall cardiovascular risk. Patients with renal dysfunction defi ned by a higher creatinine 115 mol / L (1.3 mg / dL) in patients over 50 years high overall cardiovascular risk and those with hypertension is more severe benefit most adding antiplatelet no significant increased risk of bleeding. The good control of diastolic BP below 90 mmHg is central to avoid the risk of bleeding associated with aspirin.
Antihypertensive drugs:
Antihypertensive drugs as first line:
Recall first that the various clinical trials comparing different active treatments objectify a profit from the decline in PA in itself, regardless of the molecule used.
Five classes of antihypertensive drugs can be used as first line:
– Diuretics;
– Beta-blockers;
– Angiotensin-converting enzyme from angiotensin I (IEC);
– Calcium channel blockers;
– The angiotensin AT1 receptor blockers (ARBs-2).
All these treatments are appropriate for the establishment and maintenance of antihypertensive treatment either as monotherapy or in combination.
Each class has its special properties, advantages and disadvantages that should be known for adapting your choice depending on the patient.
Beta-blockers have proven their protective effect in angina pectoris, heart failure and recent myocardial infarction.However, they are less effective for the prevention of stroke. Due to the weight gain and metabolic effects they induce (hyperlipidemia, diabetes novo), they should be avoided in patients with risk factors. These effects may not occur for newer beta blockers (carvedilol, nebivolol). These properties also apply to thiazide diuretics which have a hyperlipémiant and diabetogenic effect.
Among blacks and the elderly, diuretics and calcium channel blockers are more effective and should be preferred to beta blockers, ACE inhibitors and ARA-2.
The benefit of other therapeutic classes is much more limited (alpha, central antihypertensives).
The choice of initial treatment is less crucial to establish as many tests show the need for an association to get the blood pressure targets. Ultimately, the BP control requires combining two antihypertensive drugs in the majority (70%) of patients. The choice should be based primarily on systemic complications, associated risk factors and adverse events for each patient.
Giving and select an antihypertensive medication:
* General principles:
These are the following:
– Start with low doses of monotherapy or a fixed combination of low doses that had the authorization to market in first-line treatment;
– Focus on drugs whose effectiveness blood pressure over 24 hours is well documented and can be administered once daily;
– The first evaluation of the effectiveness of blood pressure should be made after a period of 4 weeks;
– In case of total or side effect inefficiency change antihypertensive drug class (for example, prefer a beta blocker or an ACE inhibitor if the patient was treated with a diuretic or a calcium channel blocker and vice versa);
– In case of partial pressure response: generally prefer the combination of a second class of antihypertensive agent to increase the dose of prescribed medication alone (which is probably more physiological and often better tolerated) by having either using the free combinations either fixed combinations whose development is growing.
* Monotherapy:
Initially introduced in small doses, it can be increased for non-response or replaced with another therapeutic class first at low dose and full dose. If ineffective, another drug class will be tested. This strategy allows you to find for a given patient the most effective treatment and better tolerated. However, the response rate does not exceed 50% in monotherapy.
This procedure can be long and arduous for the patient and his doctor.
* Associations:
Ultimately, the BP control requires two antihypertensive drugs in the majority (70%) of patients.
The choice of a first-line combination is legitimate, especially in cases of high cardiovascular risk.
Associations with the synergistic effect is documented are:
– Thiazide and IEC;
– Thiazide and ARA-2;
– Calcium and IEC inhibitor;
– Calcium inhibitor and ARB-2;
– Calcium and thiazide inhibitor;
– Beta-blockers and calcium channel blocker.
The classic combination blocker / thiazide has been widely used in the tests but due to their known metabolic effects, it should be avoided in patients at risk.
Fixed combinations in one pill can improve adherence and are widely available.
Patients to be treated:
Elderly:
Those over 60 years old have antihypertensive treatment in terms of cardiovascular morbidity and mortality.Various trials have shown the efficacy of different therapeutic classes used as first line: thiazide diuretics, calcium channel blockers, ACE inhibitors or ARBs-2, or beta-blockers. All trials showed a benefit of treatment versus placebo. The analysis of subgroups of patients over 65, even over 80 years, also showed that profit regardless of the therapeutic class used. There is no recommended strategy in the selection of the molecule according to the age. Initiation of antihypertensive treatment in elderly patients should be cautious, with lower initial doses and the systematic search of orthostatic hypotension prior to treatment. Many patients already have organ damage that should guide the choice of treatment.
Often, two molecules are needed to achieve a sufficient drop in systolic BP of less than 140 mmHg.
Diabetics:
The goal blood pressure is below 130/80 mmHg, with a benefit of ACE inhibitors and ARBs-2 on the prevention of the progression of nephropathy. The lifestyle measures are particularly important and an enhanced control of lipid.
History of stroke:
Various trials have shown the efficacy of antihypertensive therapy in secondary prevention of stroke, ischemic or hemorrhagic, even when the initial BP was less than 140/90 mmHg. The level of PA to achieve is not precisely known, but the analysis of Progress suggests a target below 130 mmHg systolic BP. If the role of blood pressure reduction is well established, further studies are needed to compare different antihypertensive treatments. The ARA-2 seem particularly effective.
Nondiabetic renal disease:
Renal disease and renal failure associated with a high cardiovascular risk.
Prevention of renal failure requires strict AP levels (<130/80 mmHg), and even lower if there is proteinuria. In renal insufficiency and proteinuria target is even lower at 120/70 mmHg.
To reduce proteinuria, an ACE inhibitor, an ARB-2 or the combination of both is indicated, subject to careful monitoring of serum potassium and creatinine.
Hypertension in women:
Women have a lower PA than men in the age group 30-44 years and the frequency and PA figures rise and exceed those of men after 60 years. The response to treatment and earnings are similar in both sexes. Nevertheless inhibitors of the renin-angiotensin-aldosterone system should be avoided in pregnancy or pregnancy desire because of their teratogenic risk.
Role of oral contraception:
Oral contraceptives are responsible for an increase of moderate PA for most women and genuine HTA in 5% of them. The risk of cardiovascular complications is present in women over 35 years and in smokers. Hypertension induced by oral contraception is moderate and reversible within six months after stopping treatment. Estrogen is considered responsible for the elevation of the PA but the mechanisms involved are unknown. Progestogen-only oral contraceptives are choices in hypertensive women.
Hypertension in pregnancy:
BP 15 mmHg decrease physiologically during the second trimester of pregnancy in women but normo- hypertension.The definition of hypertension during pregnancy is currently holding greater than or equal to 140/90 mmHg PA, taken twice.
In patients with moderate hypertension (140-149 / 90-95), close monitoring will be introduced to limit the activities of pregnant women with hypertension. A normal diet without salt restriction is recommended. The low-dose aspirin is indicated in patients with a history of preeclampsia before 28 weeks.
For numbers of senior PA or equal to 150/95, pharmacological treatment is indicated.
If the PA exceeds 170/110, there is a therapeutic need for emergency with emergency hospitalization. Useful treatments are labetalol parenterally, orally or methyldopa nifedipine orally. The antagonists of the renin-angiotensin system are strictly against-indicated, atenolol is associated with a risk of fetal growth restriction and diuretics at risk of hypovolemia. Magnesium sulfate intravenously is effective in the prevention of eclampsia. Finally, the trigger may be necessary if visual disturbances, coagulation abnormalities or fetal distress appear.
Remote cardiovascular risk is increased in women with a history of hypertension in pregnancy.
Metabolic syndrome:
The metabolic syndrome is obesity and various abnormalities of glucose metabolism, lipid and hypertension. Its prevalence increases with age. It is characterized by cardiovascular risk and increased risk of diabetes or hypertension de novo, frequent association with subclinical organ damage (microalbuminuria, arterial stiffness, left ventricular hypertrophy …). Metabolic syndrome is often associated with inflammatory disease that may contribute to its atherogenic effect.
The lifestyle measures are essential in these patients. The objective optimal blood pressure is unknown in the metabolic syndrome but antihypertensive treatment is indicated when the PA exceeds 140/90 mmHg. The treatments of choice are ARA-2 and IEC that are associated with a lower incidence of diabetes as beta-blockers and thiazides.
These deleterious effects seem less pronounced with the new vasodilating beta blockers (carvedilol, nebivolol).
When referral to a specialist?
Many situations require a referral to a specialist.
Resistant hypertension:
Hypertension is considered resistant when NOT exceed 160 mmHg and / or DBP greater than or equal to 100 mmHg at two successive consultations despite the prescription of a triple therapy “logic”, that is to say comprising a diuretic .It is advisable to entrust the management of treatment by a specialist. Some common causes of resistance:
– Poor adherence;
– Unknown secondary hypertension (nephropathy, renovascular hypertension, primary aldosteronism, pheochromocytoma, Cushing’s syndrome, sleep apnea syndrome …)
– Decision of hypertension-inducing drugs;
– Excessive weight gain;
– Excessive alcohol consumption;
– Extracellular volume “excessive” (insufficient diuretic therapy or poorly distributed, excessive sodium intake, renal failure);
– Pseudo-resistance, hypertension associated with white coat, measurement issues (inappropriate cuff, etc.).
The use of a specialist is necessary because resistant hypertension is associated with subclinical organ damage and a high cardiovascular risk. Ultimately, many patients will need more than three applications, small-dose aldactone (25 to 50 mg / day) has shown its effectiveness in reducing BP in combination with multiple treatments.
Hypertensive emergencies:
They are defined by the worsening of organ damage related to high BP.
They may involve the prognosis and management should be fast while avoiding overly abrupt declines in PA that can be complicated by cerebral hypoperfusion or cerebral infarction, infarction or kidney.
Malignant hypertension:
Malignant hypertension is a syndrome with severe hypertension (diastolic BP> 140 mmHg) and vascular lesions such qu’hémorragies retinal exudates, or papilledema. Insufficiently treated essential hypertension is most frequently involved. It develops more readily in smokers and in blacks than Caucasians. Its prevalence decreased with earlier treatment of hypertension.
The achievement is the most severe hypertensive encephalopathy which is accompanied by irreversible neurological damage including headache, visual acuity disorders and premium features. In some patients, an irreversible deterioration of renal function requires support on chronic dialysis. Malignant hypertension is accompanied by a mechanical hemolysis (presence of fragmented or schizocytes RBCs) and disseminated intravenous coagulation signs.Without treatment, the prognosis of malignant hypertension is extremely dark, with a mortality rate of 50% at 12 months. When effective treatment is initiated, survival is better. Malignant hypertension should be considered as a hypertensive emergency.
Oral therapy can be given if it is effective with the goal of reducing diastolic BP at 100-110 mmHg emergency.
Follow-up:
During the phase of initiation of treatment, the patient should be seen every 2 to 4 weeks to adjust the doses and different treatments.
During this period, self-measurement can be taught to the patient. Once achieved, blood pressure and various cardiovascular risk factors, visits can be spaced every six months in patients with moderate hypertension, providing more frequent checks if hypertension is severe or high cardiovascular risk . The frequency of visits can improve patient compliance during treatment that should be continued indefinitely.
If the target blood pressure is not reached after six months, the patient should be referred to a specialist.
Frequent monitoring allows to detect organ damage that can occur in a few weeks to several months for proteinuria or left ventricular hypertrophy.
CONCLUSION:
Although hypertension is a major cardiovascular risk factor and that his treatment provides a reduction in the risk of serious accidents, many studies show that:
– Many patients do not know their blood pressure;
– Target blood pressure are rarely achieved, the patient is monitored by a specialist or a generalist.
Systolic hypertension is particularly difficult to control and the target below 130/80 mmHg in diabetic patients and high-risk patients, exceptionally reached. This explains why hypertension remains a major cause of death and cardiovascular morbidity in industrialized countries and in developing countries.