Description

• Primary hypertension (HTN) is HTN without an identifiable cause; also known as essential HTN. An importance risk factor for CV disease and other morbidity and mortality, there is persistent controversy regarding recommended thresholds for diagnosis and treatment.
• HTN is defined (Joint National Committee [JNC] 8 and the International Society of Hypertension) as (all pressures in mm Hg) (1):
  • Age <60 years: systolic BP (SBP) ≥140 and/or diastolic BP (DBP) ≥90 at ≥2 visits
  • Age ≥60 years: SBP ≥150 and/or DBP ≥90 at ≥2 visits
  • With diabetes or chronic kidney disease (CKD): SBP ≥140 and/or DBP ≥90
  • The American College of Cardiology (ACC)/American Heart Association (AHA) designates SBP ≥130 and/or DBP ≥80 as “stage 1 hypertension” which should be treated with exercise and lifestyle modification, reserving medication for patients at “higher risk” (defined as age ≥65 years, CKD, diabetes, or known cardiovascular disease [CVD]).

Geriatric Considerations
Isolated systolic HTN is common. Therapy is effective at preventing stroke, CV morbidity and all-cause mortality (2)[A]. Target SBP for seniors is higher than in younger patients (~150 mm Hg systolic), and adverse reactions to medications are more frequent, especially in those who are very old. The benefit of therapy has been conclusively demonstrated in older patients for SBP ≥160. The strongest evidence of benefit has been shown with use of thiazide diuretics.

Pediatric Considerations
Defined as SBP or DBP ≥95th percentile on repeated measurements; measure BP during routine exams beginning at age 3 years; pre-HTN: SBP or DBP between 90th and 95th percentile

Pregnancy Considerations
Elevated BP during pregnancy may represent chronic HTN, pregnancy-induced HTN, or preeclampsia. Preferred agents: labetalol, nifedipine, methyldopa, or hydralazine with angiotensin-converting enzyme inhibitors (ACEI) and angiotensin II receptor blockers (ARBs) being contraindicated. Maternal and fetal mortality are reduced with treatment of severe HTN (see “Preeclampsia and Eclampsia [Toxemia of Pregnancy]”).

Epidemiology

Prevalence
32–46% of adults in the United States have HTN; incidence and prevalence higher in men

Etiology and Pathophysiology

>90% of cases of HTN have no identified cause. For differential diagnosis and causes of secondary HTN, see “Hypertension, Secondary and Resistant.”

Risk Factors

Family history, obesity, alcohol use, excess dietary sodium, stress, physical inactivity, tobacco use, insulin resistance, obstructive sleep apnea (OSA) and other causes of sleep disruption