From the Guidelines
Isolated high diastolic blood pressure with normal systolic pressure is primarily caused by increased peripheral vascular resistance, and it is crucial to address this condition to prevent cardiovascular complications. The causes of isolated high diastolic blood pressure with normal systolic pressure can be attributed to various factors, including:
- Obesity
- Excessive alcohol consumption
- High sodium intake
- Sedentary lifestyle
- Stress
- Certain medications like NSAIDs, oral contraceptives, and some antidepressants
- Medical conditions such as kidney disease, thyroid disorders (particularly hypothyroidism), sleep apnea, and adrenal gland problems 1. Age is also a significant factor, as isolated diastolic hypertension is more common in younger adults under 50 1. This condition occurs because the arteries remain constricted during the heart's relaxation phase, maintaining high pressure even when the heart isn't actively pumping. While sometimes considered less serious than systolic hypertension, isolated diastolic hypertension still requires attention as it can lead to cardiovascular complications if left untreated, as evidenced by the increased risk of CHD, heart failure, CVD, peripheral vascular disease, and renal failure associated with elevated BP levels 1. Lifestyle modifications like weight loss, reduced sodium and alcohol intake, regular exercise, and stress management are typically the first-line treatments, with medications like ACE inhibitors, ARBs, or calcium channel blockers added if lifestyle changes are insufficient, aiming for a BP target of less than 130/80 mm Hg, as recommended for adults with hypertension 2.
From the Research
Causes of Isolated High Diastolic Blood Pressure
- Isolated high diastolic blood pressure with normal systolic pressure can be caused by an increase in systemic resistance, which results in a rise in diastolic blood pressure 3
- The loss of elasticity of conductance arteries can also lead to a decrease in diastolic run-off, resulting in high diastolic blood pressure 3
- Isolated diastolic hypertension (IDH) is more common in young subjects and is associated with adverse cardiovascular events in this population 4
- In older subjects, IDH is less common and is not associated with adverse cardiovascular events, and treatment should be individualized to avoid decreasing normal systolic blood pressure and preventing adverse cardiovascular events 4
Pathophysiology
- Arterial hypertension is the result of abnormal flow/resistance relationships, with resistance to outflow consisting of different components, including systolic and diastolic components 3
- The diastolic component consists of peripheral resistance, which regulates peripheral blood supply due to the run-off of conductance vessels during left ventricular diastole 3
- An increase in systemic resistance results in a rise in diastolic blood pressure, while a decrease in the elasticity of conductance vessels can lead to a decrease in diastolic run-off and high diastolic blood pressure 3
Clinical Significance
- The prevalence of IDH has increased with the new 2017 ACC/AHA blood pressure treatment guidelines, and its clinical significance as a cause of adverse cardiovascular events is debated 4
- Treatment of IDH in younger subjects is recommended, while in older subjects, treatment should be individualized to avoid adverse cardiovascular events 4
- Diastolic blood pressure and isolated diastolic hypertension drive coronary risk in younger subjects, whereas systolic blood pressure is the predominant risk indicator in older people 5