What is the primary recommendation for managing diastolic pressure in an adult patient?

Managing Diastolic Blood Pressure in Adults

For most adults with hypertension, diastolic blood pressure should be treated to a target of <80 mmHg, with treatment initiation recommended when diastolic BP reaches ≥80 mmHg in high-risk patients or ≥90 mmHg in lower-risk patients. 1, 2

Treatment Thresholds by Risk Category

High-Risk Patients (CVD, diabetes, CKD, or 10-year ASCVD risk ≥10%)

• Initiate antihypertensive therapy at DBP ≥80 mmHg 1, 2
• Target DBP <80 mmHg 1, 2
• The European Society of Cardiology further refines this, suggesting that when systolic BP is already at target (120-129 mmHg) but diastolic remains ≥80 mmHg, intensifying treatment to achieve DBP 70-79 mmHg may reduce cardiovascular risk 1

Lower-Risk Patients

• Initiate treatment at DBP ≥90 mmHg 1
• This threshold has the strongest evidence base, supported by randomized controlled trials dating back to the 1960s with "A" level evidence 1
• Target remains <80 mmHg once treatment is initiated 1

Isolated Diastolic Hypertension (DBP 90-100 mmHg with normal systolic)

• Start combination BP-lowering medication immediately 3
• Preferred initial combination: RAS blocker (ACE inhibitor or ARB) plus either a dihydropyridine calcium channel blocker or thiazide/thiazide-like diuretic 3
• Target DBP 70-79 mmHg 3

Critical Evidence Considerations

The 2017 ACC/AHA guideline's recommendation to treat DBP ≥80 mmHg in high-risk patients is based primarily on expert opinion (Class C-EO evidence), not randomized trial data 1. The strongest trial evidence supports treating DBP ≥90 mmHg 1. The single major trial (HOT) comparing DBP goals found no significant benefit of targeting <80 mmHg versus higher targets in the general population, except in a post-hoc diabetes subgroup analysis 1.

The concern about over-treating diastolic BP (the "J-curve" hypothesis) has not been demonstrated in randomized trials, only in observational analyses 1. Recent data show that low DBP (<60 mmHg) occurring naturally is associated with increased mortality, but treatment-induced low DBP does not appear to increase risk further 4.

First-Line Medication Selection

Standard First-Line Agents (all have proven CVD outcome benefits)

• Thiazide diuretics (especially chlorthalidone for older adults) 1
• ACE inhibitors or ARBs 1
• Calcium channel blockers 1
• Beta-blockers are less effective than diuretics for stroke prevention and should not be first-line unless specific indications exist (age <60, post-MI, heart failure, angina) 1

Specific Populations

• Black patients: Thiazide diuretics or calcium channel blockers preferred over ACE inhibitors/ARBs 1
• Diabetes or CKD: ACE inhibitors or ARBs as first-line 1, 5
• Older adults: Thiazide diuretics particularly beneficial for heart failure prevention 1

Treatment Intensification Algorithm

1. If DBP not controlled on single agent: Add second drug from different class 2, 3
2. If DBP not controlled on two drugs: Add third agent (typically completing the triad of RAS blocker + calcium channel blocker + thiazide diuretic) 1, 3
3. Resistant hypertension (uncontrolled on 3 drugs including diuretic): Add spironolactone as fourth agent 1

Important Caveats

• Accurate measurement is essential: Patient seated quietly for ≥5 minutes, back supported, feet flat, arm at heart level, proper cuff size, no conversation, empty bladder 2
• Confirm diagnosis with out-of-office measurements (home BP monitoring or 24-hour ambulatory monitoring) before initiating treatment 2, 3
• Avoid alpha₁ blockers and central alpha₂ agonists in older adults due to increased adverse effects 1
• Monthly follow-up until BP control achieved, then every 3-6 months 2
• Most patients require ≥2 medications to achieve target BP <130/80 mmHg 1, 2, 5