Understanding Hypertension
Diagnostic Evaluation
These recommendations are presented in abbreviated form. Readers should refer to the complete guideline document1 for a detailed discussion of each of the following topics.
Diagnostic procedures are aimed at: (1) establishing blood pressure levels; (2) identifying secondary causes of hypertension; (3) evaluating the overall cardiovascular risk by searching for other risk factors, target organ damage and concomitant diseases or accompanying clinical conditions.
The diagnostic procedures comprise:
- repeated blood pressure measurements;
- medical history;
- physical examination;
- laboratory and instrumental investigations, some of which should be considered part of the routine approach in all subjects with high blood pressure, some which are recommended and may be used extensively (at least in the highly developed health systems of Europe), and some which are indicated only when suggested by some of the core examinations or the clinical course of the patient.
Blood pressure measurement
- Blood pressure values measured in the doctor’s office or the clinic should commonly be used as reference.
- Twenty-four-hour ambulatory blood pressure monitoring may be considered of additional clinical value, when:– considerable variability of office blood pressure is found over the same or different visits;
- high office blood pressure is measured in subjects otherwise at low global cardiovascular risk;
- there is marked discrepancy between blood pressure values measured in the office and at home;
- resistance to drug treatment is suspected;
- research is involved.
- Self-measurement of blood pressure at home should be encouraged in order to:
- provide more information for the doctor’s decision;
- improve patient’s adherence to treatment regimens.
- Self-measurement of blood pressure at home should be discouraged whenever:
- it causes patients anxiety;
- it induces self-modification of the treatment regimen.
- Normal values are different for office, ambulatory and home blood pressure
Medical History - Family and Clinical
- Duration and previous level of high blood pressure.
- Indications of secondary hypertension:
- family history of renal disease (polycystic kidney);
- renal disease, urinary tract infection, haematuria, analgesic abuse (parenchymal renal disease);
- drug/substance intake: oral contraceptives, liquorice, carbenoxolone, nasal drops, cocaine, amphetamines, steroids, non-steroidal anti-inflammatory drugs, erythropoietin, cyclosporin;
- episodes of sweating, headache, anxiety, palpitation (phaeochromocytoma);
- episodes of muscle weakness and tetany (aldosteronism).
- Risk factors:
- family and personal history of hypertension and cardiovascular disease;
- family and personal history of hyperlipidaemia;
- family and personal history of diabetes mellitus;
- smoking habits;
- dietary habits;
- obesity; amount of physical exercise;
- personality.
- Symptoms of organ damage
- brain and eyes: headache, vertigo, impaired vision, transient ischaemic attacks, sensory or motor deficit;
- heart: palpitation, chest pain, shortness of breath, swollen ankles;
- kidney: thirst, polyuria, nocturia, haematuria;
- peripheral arteries: cold extremities, intermittent claudication.
- Previous antihypertensive therapy:
- drugs used, efficacy and adverse effects
- Personal, family and environmental factors.
Physical Examination secondary hypertension and organ damage
Signs suggesting secondary hypertension and organ damage
- Features of Cushing syndrome.
- Skin stigmata of neurofibromatosis (phaeochromocytoma).
- Palpation of enlarged kidneys (polycistic kidney).
- Auscultation of abdominal murmurs (renovascular hypertension).
- Auscultation of precordial or chest murmurs (aortic coarctation or aortic disease).
- Diminished and delayed femoral and reduced femoral blood pressure (aortic coarctation, aortic disease).
Signs of organ damage
- Brain: murmurs over neck arteries, motor or sensory defects.
- Retina: funduscopic abnormalities.
- Heart: location and characteristics of apical impulse, abnormal cardiac rhythms, ventricular gallop, pulmonary rales, dependent oedema.
- Peripheral arteries: absence, reduction, or asymmetry of pulses, cold extremities, ischaemic skin lesions.
Laboratary Investigations
Routine tests
- Plasma glucose (preferably fasting)
- Serum total cholesterol
- Serum high-density lipoprotein (HDL)-cholesterol
- Fasting serum triglycerides
- Serum uric acid
- Serum creatinine
- Serum potassium
- Haemoglobin and haematocrit
- Urinalysis (dipstick test complemented by urinary sediment examination)
- Electrocardiogram
Recommended tests
- Echocardiogram
- Carotid (and femoral) ultrasound
- C-reactive protein
- Microalbuminuria (essential test in diabetics)
- Quantitative proteinuria (if dipstick test positive)
- Funduscopy (in severe hypertension)
Extended evaluation (domain of the specialist)
- Complicated hypertension: tests of cerebral, cardiac and renal function
- Search for secondary hypertension: measurement of renin, aldosterone, corticosteroids, catecholamines; arteriography; renal and adrenal ultrasound; computer-assisted tomography (CAT); brain magnetic resonance imaging.
References:
1. 2003 European Society of Hypertension–European Society of Cardiology guidelines for the management of arterial hypertension. Journal of Hypertension 2003, 21:1011–1053. Available at: http://www.eshonline.org/