What are the normal ranges and management strategies for blood pressure in adults?

Blood Pressure Explained: Normal Ranges and Management

Blood Pressure Classification

The 2017 ACC/AHA guidelines define normal blood pressure as less than 120/80 mmHg, with hypertension beginning at 130/80 mmHg—a significant departure from older thresholds. 1, 2

Blood pressure is classified into four distinct categories based on the higher of the two readings (systolic or diastolic):

• Normal BP: <120/<80 mmHg 2
• Elevated BP: 120-129/<80 mmHg (systolic elevated but diastolic still normal) 2
• Stage 1 Hypertension: 130-139/80-89 mmHg 2
• Stage 2 Hypertension: ≥140/≥90 mmHg 2

Understanding the Risk Gradient

The relationship between blood pressure and cardiovascular disease is continuous and progressive—there is no "safe" threshold where risk suddenly appears. 3 Risk doubles for every 20 mmHg systolic or 10 mmHg diastolic increase. 2 Even at the elevated BP range (120-129/<80 mmHg), hazard ratios for coronary heart disease and stroke are 1.1-1.5 times higher compared to normal BP, and this increases to 1.5-2.0 times at Stage 1 hypertension levels. 2

By middle age, only about 20% of Americans have optimal blood pressure levels below 120/80 mmHg. 3 A blood pressure of 115/75 mmHg is associated with minimal vascular mortality and likely constitutes truly optimal blood pressure. 4

Accurate Blood Pressure Measurement

Proper measurement technique is critical—inaccurate readings lead to misdiagnosis and inappropriate treatment decisions. 5, 2

Blood pressure diagnosis must be based on an average of at least 2 readings obtained on at least 2 separate occasions. 2 The patient must be:

• Seated quietly for ≥5 minutes with back supported 2
• Feet flat on floor, not dangling 2
• Arm at heart level on a supported surface 2
• Using proper cuff size on bare arm 2
• No conversation during measurement 2
• Empty bladder 2

Home and Ambulatory Monitoring

Out-of-office blood pressure measurements using home blood pressure monitoring (HBPM) or ambulatory blood pressure monitoring (ABPM) should be used to confirm diagnosis before initiating treatment. 2

For HBPM, take at least 2 readings 1 minute apart in the morning before medications and in the evening before supper, recording all readings accurately. 1 Blood pressure should be based on an average of readings on ≥2 occasions for clinical decision making. 1

HBPM targets differ from clinic readings:

• Clinic BP ≥140/90 mmHg corresponds to HBPM ≥135/85 mmHg 1
• Clinic BP ≥130/80 mmHg corresponds to HBPM ≥130/80 mmHg 1

Screen for white coat hypertension in adults with untreated systolic BP 130-160 mmHg or diastolic BP 80-100 mmHg using ABPM or HBPM before diagnosing hypertension. 1 Screen for masked hypertension with HBPM in adults with untreated office BPs consistently 120-129/75-79 mmHg. 1

Management Strategy by Blood Pressure Stage

Normal BP (<120/<80 mmHg)

• Continue healthy lifestyle habits 2
• Reassess annually 2

Elevated BP (120-129/<80 mmHg)

• Implement nonpharmacologic interventions (lifestyle modifications) 2
• Reassess in 3-6 months 2
• No medication indicated unless high cardiovascular risk 2

Stage 1 Hypertension (130-139/80-89 mmHg)

The treatment approach depends on cardiovascular risk assessment:

For LOW-risk patients (10-year ASCVD risk <10%):

• Start with lifestyle modifications alone 2
• Initiate drug therapy only if BP remains ≥140/90 mmHg after 3-6 months 2

For HIGH-risk patients (10-year ASCVD risk ≥10%, or diabetes, or chronic kidney disease):

• Start lifestyle modifications PLUS single antihypertensive agent immediately 2
• Target BP <130/80 mmHg 2

Stage 2 Hypertension (≥140/≥90 mmHg)

Immediately initiate both nonpharmacologic therapy AND antihypertensive medications, typically starting with 2 agents of different classes. 2, 6

For patients with BP ≥160/≥100 mmHg:

• Two-drug combination therapy is recommended for most patients 6
• Preferred initial combination: thiazide-type diuretic plus ACE inhibitor, ARB, beta-blocker, or calcium channel blocker 6
• Monthly evaluation of adherence and therapeutic response until control is achieved 1, 6
• Prompt adjustment of regimen until control is achieved 1

Treatment Targets

The target BP for most patients is <130/80 mmHg. 2

This applies to:

• Adults with confirmed hypertension and known cardiovascular disease or 10-year ASCVD risk ≥10% (Class I recommendation) 2
• Adults with diabetes 1, 2
• Adults with chronic kidney disease 1, 2

Special Populations

For older adults (≥65 years):

• Target systolic BP <130 mmHg for ambulatory, community-dwelling adults 5
• Randomized trials have demonstrated that more intensive BP-lowering therapy safely reduced cardiovascular events for adults older than 65,75, and 80 years 5
• BP-lowering therapy is one of few interventions shown to reduce mortality risk in frail older adults 5
• Initiation of therapy, especially with 2 drugs, should be done with caution, with careful monitoring for adverse effects including orthostatic hypotension 1
• For patients ≥85 years with symptomatic orthostatic hypotension, a more lenient target of <140/90 mmHg may be considered 2

For patients with diabetes:

• Initiate antihypertensive drug treatment at BP ≥130/80 mmHg 1
• Target BP <130/80 mmHg 1
• Most adults with diabetes and hypertension have 10-year ASCVD risk ≥10%, placing them in high-risk category 1

For patients with chronic kidney disease:

• Initiate treatment at BP ≥130/80 mmHg 1
• Target BP <130/80 mmHg 1, 6
• Use ACE inhibitor or ARB as initial or add-on therapy to improve kidney outcomes 7

Medication Selection

For the general nonblack hypertensive population (including those with diabetes):

• Initiate with ACE inhibitor, ARB, calcium channel blocker, or thiazide-type diuretic 7

For the black hypertensive population (including those with diabetes):

• Initiate with calcium channel blocker or thiazide-type diuretic 7

For chronic kidney disease:

• Use ACE inhibitor or ARB to improve kidney outcomes 7

For resistant hypertension:

• Spironolactone is favored as first-line agent if not contraindicated 2

Monitoring and Follow-Up

Monthly follow-up is recommended for adults initiating new or adjusted antihypertensive therapy until BP control is achieved. 2

Interventions to promote control include:

• Systematic use of HBPM 2, 8
• Team-based care 1, 8
• Telehealth strategies 1, 8

Common Pitfalls to Avoid

Measurement errors: Failing to use proper BP measurement technique leads to inaccurate readings and inappropriate treatment decisions. 5, 2

Delayed treatment: Delaying treatment for patients with BP ≥160/≥100 mmHg is dangerous—prompt intervention is essential. 6

Inadequate initial therapy: Using monotherapy instead of combination therapy for initial treatment of BP ≥160/≥100 mmHg results in delayed control. 6

Ignoring orthostatic hypotension: This is particularly important in older adults and can lead to falls and injury. 5

Not considering individual factors: Failing to account for comorbidities, life expectancy, and patient preferences when determining BP goals, especially in older adults with high comorbidity burden. 5

Inadequate follow-up: Failing to achieve target BP within 3 months or not monitoring frequently enough in patients with severe hypertension. 6