hypertension
HYPERTENSION
Hypertension is the medical term for high blood pressure. Persistent high blood pressure can lead to increased strain to the heart and arteries that can eventually cause organ damage.
To classify the blood pressure, it must be based on ≥2 properly measured, seated blood pressure readings on each of ≥2 office visits.
Patients who have a blood pressure reading of 130 SBP or ≥80 DBP or both can be diagnosed as hypertensive patients.
Goals of therapy are to manage hypertension that can maintain the patient's normal blood pressure and identify and treat all reversible risk factors.

Classification

  • Classification must be based on the average of ≥2 properly measured, seated BP readings on each of ≥2 office visits
  • Various consensus guidelines are available as standard references for the definition of hypertension
  • BP Classification based on 
    2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA*
    SBP (mmHg)     DBP (mmHg)
    Normal
      <120   and   <80
    Elevated
      120-129   and   <80
    Hypertension Stage 1
      130-139   or   80-89
    Hypertension Stage 2
      ≥140   or   ≥90
     
    BP Classification based on 2013 ESH-ESC** SBP (mmHg)      DBP (mmHg)
    Optimal
      <120   and   <80
    Normal
      120-129   and/or   80-84
    High Normal
      130-139   and/or   85-89
    Grade 1 hypertension
      140-159   and/or   90-99
    Grade 2 hypertension
      160-179   and/or   100-109
    Grade 3 hypertension
      ≥180   or   ≥110
    Isolated systolic hypertension (ISH)
      ≥140   and   <90

*Adapted from: 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the prevention, detection, evaluation, and management of high blood pressure in adults. This guideline updates prior JNC reports.
**Similar BP classification is also used by the Indonesian Heart Association (PERKI) 2015 and National Heart Foundation of Australia 2016.

Risk Stratification

  • All patients should be classified not only in relation to stages of hypertension but also in terms of total cardiovascular (CV) risk resulting from coexistence of different risk factors, organ damage and disease
  • Decisions on management of hypertension should be based on BP levels along with other CV risk factors and target organ damage (TOD)
  • A study revealed that in patients being given aggressive antihypertensive therapy, prolonged QRS duration confers higher risk of sudden cardiac death in this subset of patients
  • SBP is better in quantifying prognosis than DBP in patients >50 years old
    • In younger patients without comorbidities, DBP is a more important CV risk factor
  • Pulse pressure is also a good predictor of CV events in elderly patients
  • To estimate the 10-year risk of atherosclerotic CVD (ASCVD), the ACC/AHA pooled cohort equations may be used (http://tools.acc.org/ASCVD-Risk-Estimator/)  
    • ASCVD was defined as 1st CHD death, fatal or non-fatal stroke, or non-fatal MI 
RISK STRATIFICATION TO QUANTIFY PROGNOSIS
Blood pressure (mmHg) No other risk factors 1-2 risk factors ≥3 risk factors, TOD TOD, CKD Stage 3 or Diabetes Symptomatic CVD, CKD Stage ≥4 or Diabetes with TOD/RFs
 
SBP 130-139 or DBP 85-89   Low risk Low to Moderate risk Moderate to High risk Very High risk
SBP 140-159 or DBP 90-99 Low risk Moderate risk Moderate to High risk High risk Very High risk
SBP 160-179 or DBP 100-109 Moderate risk Moderate to High risk High risk High risk Very High risk
SBP ≥ 180 or DBP ≥ 110 High risk High risk High risk High to Very High risk Very High risk
Adapted from: 2013 European Society of Hypertension-European Society of Cardiology guidelines for the management of arterial hypertension

Evaluation

  • If patient is found to have chronic elevated BP, then they should undergo further assessment to determine secondary causes, TOD, CVD risk factors or concomitant disorders that will affect prognosis

Identifiable Secondary Causes of Hypertension

  • Chronic kidney disease (CKD)
  • Chronic steroid therapy and Cushing Syndrome
  • Coarctation of the aorta
  • Alcohol- or drug-induced
    • Prescription, over-the-counter medications, herbal supplement, use of illicit drugs, etc
  • Takayasu arteritis
  • Obesity
  • Pheochromocytoma
  • Primary aldosteronism
  • Renovascular disease
  • Obstructive sleep apnea
  • Thyroid and parathyroid disorders
  • Congenital adrenal hyperplasia

CVD Risk Factors

  • Increased age
  • Male sex
  • Smoking
  • Unhealthy diet/physical inactivity
  • Low educational or socioeconomic status
  • Psychosocial stress
  • Diabetes mellitus
  • Obesity
  • Dyslipidemia
  • Obstructive sleep apnea
  • Chronic kidney disease
  • Family history of premature CV disease (<55 years for male relative or <65 years for female relative)
  • Abdominal obesity [waist circumference: Men ≥102 cm; women ≥88 cm (Caucasian)]

Target Organ Damage (TOD)

  • Heart: Left ventricular (LV) hypertrophy, angina/prior MI, prior coronary revascularization, heart failure
  • Brain: Stroke or transient ischemic attack (TIA), dementia
  • Kidney: Chronic kidney disease
  • Vascular: Peripheral arterial disease
  • Eyes: Retinopathy

History

  • History should be taken with emphasis on hypertension, DM, dyslipidemia and premature coronary heart disease (CHD), stroke or renal disease
    • Level and duration of elevated BP
    • Usual range of BP; current/past antihypertensive medications and history of adherence to treatment
    • Symptoms of secondary causes of hypertension (eg sweating, headache and palpitations in pheochromocytoma; muscle weakness and tetany in hyperaldosteronism; hypersomnolence and snoring in obstructive sleep apnea; heat intolerance, weight loss and palpitations in hyperthyroidism; fatigue, edema, and frequent urination in kidney disease or failure)
    • Lifestyle and environmental evaluation (eg dietary intake of fat, salt and alcohol, physical activity, smoking status, weight gain since young adulthood)
    • Medication history of prescribed and over-the-counter medications, use of herbal supplements and illicit drugs
    • History or current symptoms of TOD (eg CHD, cerebrovascular disease, cognitive dysfunction)
    • History or current symptoms of concomitant diseases that will affect prognosis (eg DM, renal disease, gout, UTI, thyroid disease, etc)
    • Family history of high BP, stroke, diabetes, chronic kidney disease (CKD), cardiovascular disease (CVD), CHD, renal disease and dyslipidemia
    • Occupational history (eg with frequent travels or long trips, consider time changes, medication schedule, prevention of complications, etc)

Physical Examination

  • Appropriate BP measurement with verification in contralateral arm
  • Examination of optic fundi
  • Calculation of body mass index (BMI) and waist circumference - risk for metabolic syndrome or for type 2 DM is high when waist circumference is >102 cm in men, >88 cm in women
  • Heart rate (patient at rest)
  • Auscultation for carotid, abdominal and femoral bruits
  • Thorough exam of heart and lungs; palpation of the thyroid gland
  • Exam of the abdomen for truncal obesity, enlarged kidneys, masses, distended urinary bladder and abnormal aortic pulsation
  • Palpation of lower extremities for edema and pulses, eg ankle-brachial index (ABI)
  • Neurological assessment

Laboratory Tests

  • Should be done to exclude secondary causes, provide evidence for additional risk factors and note the occurrence of TOD
    • CBC, urinalysis, renal function test, fasting blood sugar, lipid profile (after 9- to 12-hour fast), serum creatinine, serum K and Na, serum uric acid, liver function tests, thyroid stimulating hormone, 12-lead ECG

Presence of Secondary Cause or Evidence of TOD

  • Consider to screen for secondary hypertension in the following: Abrupt development of hypertension, onset of hypertension in patients <30 years old, onset of diastolic hypertension in patients ≥65 years old, hypertension that is either drug-resistant or accelerated/malignant, exacerbation of a previously controlled hypertension, TOD that is out of proportion to the degree of hypertension, excessive or unprovoked hypokalemia 
  • Patient should be referred to a specialist and treated appropriately if a secondary cause of hypertension is found
  • Further tests should be done if TOD is found in order to evaluate the level of severity

Assessment

Clinical/Office BP Measurement

  • BP is measured every 2 years in >18 years old but more frequently in those at moderate or high risk of vascular disease
  • Patient should be seated comfortably for >5 minutes in a chair, with back supported, feet on the floor and arm supported at heart level prior to measurement of BP
    • Measurement of BP in the standing position is recommended for patients at risk of postural hypotension
  • 2 measurements should be taken spaced by 1-2 minutes
    • A difference of >20/10 mmHg between 2 arms suggest arterial problems and requires further investigation
    • Take BP measurements from sitting, lying, and standing (usually after 1 minute) positions to take note of drops in BP
  • Cuff with bladder 12-13 cm wide and 35 cm long should be used and placed at heart level of the patient
    • Wider cuffs (>32 cm circumference) are needed for large arms and smaller cuffs for thin arms
    • Bladder length should encircle at least 80% of the arm while the width should be at least 40% of arm circumference
  • Use the appearance of phase I Korotkoff’s sounds for SBP and the disappearance of phase V for DBP

Confirmation of Hypertension

  • In general, diagnosis is confirmed by taking the BP 1-4 weeks after the first measurement (or the average of readings on ≥2 occasions); in these times, the SBP should be ≥130 mmHg or DBP ≥80 mmHg, or both

Out-of-Office BP Measurement

  • Ambulatory BP Monitoring (ABPM)
    • Automatically measures patient’s BP at regular intervals over a 24-hour period
    • Advantages: Detects masked/white coat hypertension; determines nocturnal BP patterns; evaluates impact of antihypertensive treatments
  • Home BP Monitoring (HBPM)
    • Self-measurement of BP for over 5-7 days, if possible in duplicate measurement
    • May also be used to screen for masked/white coat hypertension
    CORRESPONDING BP VALUES BASED ON SITE/METHODS
    Clinic/Office HBPM ABPM
    Daytime Nighttime 24 Hours
    120/80 120/80 120/80 100/65 115/75
    130/80 130/80 130/80 110/65 125/75
    140/90 135/85 135/85 120/70 130/80
    160/100 145/90 145/90 140/85 145/90
    Adapted from: 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the prevention, detection, evaluation, and management of high blood pressure in adults

Resistant Hypertension

  • Target BP not achieved and patient treated with ≥3 drugs at optimal doses (including a diuretic) or BP <130/80 mmHg but patient treated with ≥4 drugs  
    • For patients not controlled on 3 drugs, maximizing diuretic therapy and adding an aldosterone antagonist (eg Spironolactone), a beta-blocker, a centrally acting agent, an alpha-blocker, or a direct vasodilator will often be helpful
  • If BP is still uncontrolled after 3 drugs at near-max doses, consider the following:
    • Inaccurate BP measurements  
    • Noncompliance to treatment regimen
    • White coat hypertension
    • Nonadherence to lifestyle modifications
    • Drug interactions
    • Secondary hypertension
    • Complications of long-standing hypertension (eg nephrosclerosis)
  • Consider referral to a hypertension specialist if after 6 months of therapy, BP remains uncontrolled
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