Blood pressure measurement captures the force of blood against artery walls, consisting of two numbers. The top number, systolic pressure, measures the force when the heart beats. The bottom number, diastolic pressure, measures the pressure in the arteries when the heart rests between beats. Think of it like a garden hose; systolic pressure is the surge when the tap is fully open, while diastolic is the remaining pressure within the hose when the tap is turned off.
Defining Elevated Diastolic Blood Pressure
The measurement of diastolic blood pressure is given in millimeters of mercury (mmHg). According to the American Heart Association, a normal diastolic reading is less than 80 mmHg. A reading between 80 and 89 mmHg is classified as stage 1 hypertension. A diastolic pressure of 90 mmHg or higher falls into the category of stage 2 hypertension.
A specific condition known as isolated diastolic hypertension (IDH) occurs when only the diastolic number is high, while the systolic pressure remains in a normal range. This condition accounts for less than 20% of all hypertension cases and is more common in younger adults. The consistent force on the arteries during the heart’s resting phase in IDH can indicate an increase in the resistance of smaller arteries. This resistance requires the heart to work harder to circulate blood throughout the body.
Primary Causes and Contributing Factors
Elevated diastolic blood pressure can stem from specific medical conditions, often referred to as secondary causes. Conditions such as renovascular disease (the narrowing of arteries to the kidneys) can disrupt normal blood flow regulation. Thyroid disorders, particularly an underactive thyroid (hypothyroidism), have been linked to increased diastolic pressure. Additionally, obstructive sleep apnea, a disorder causing repeated breathing interruptions during sleep, is a recognized cause of high diastolic pressure.
Lifestyle choices significantly contribute to the development of high diastolic pressure. A diet high in sodium and low in potassium can lead to fluid retention and increased pressure within the arteries. Excessive and regular alcohol consumption, defined as more than one or two drinks daily, is also a factor. Obesity is a major contributor, as increased body weight can lead to hormonal imbalances that affect blood pressure regulation. Chronic stress can also temporarily, but repeatedly, raise blood pressure levels.
Associated Health Complications
Persistently high diastolic pressure places continuous strain on the walls of arteries. This ongoing stress can cause the blood vessels to become stiffer and less elastic over time, a condition known as atherosclerosis. This hardening and narrowing of the arteries can lead to serious health problems. The constant high pressure can weaken the artery walls, increasing the risk of an aortic aneurysm, which is a bulge in the body’s main artery.
Damage to blood vessels from sustained diastolic hypertension elevates the risk of major cardiovascular events. It is a known risk factor for coronary artery disease, where the arteries supplying blood to the heart muscle become damaged. This can lead to a heart attack. Furthermore, the condition increases the risk of stroke, as blood vessels in the brain can be weakened or blocked.
Another serious complication is left ventricular hypertrophy, which is the thickening of the wall of the heart’s main pumping chamber. The heart muscle enlarges because it has to work harder to pump blood against the high pressure in the arteries. Over time, this extra work can weaken the heart muscle, potentially leading to heart failure, a condition where the heart can no longer pump blood effectively.
Strategies for Lowering Diastolic Pressure
Lifestyle Modifications
Lifestyle changes are a primary approach to managing elevated diastolic pressure. These include:
- Adopting the Dietary Approaches to Stop Hypertension (DASH) diet, which emphasizes fruits, vegetables, whole grains, and low-fat dairy products while limiting sodium.
- Engaging in regular physical activity, aiming for at least 150 minutes of moderate-intensity aerobic exercise like brisk walking each week.
- Maintaining a healthy weight, as losing excess pounds can directly lower blood pressure readings.
- Limiting alcohol consumption and quitting smoking, as both can contribute to higher pressure.
- Incorporating stress management techniques, such as meditation, yoga, or deep breathing exercises, to mitigate the effects of chronic stress.
Medical Treatments
When lifestyle adjustments are not sufficient, a healthcare professional may prescribe medication. The goal of these medications is to relax blood vessels or reduce the heart’s workload. Several classes of drugs are commonly used for this purpose.
Physicians may prescribe Angiotensin-Converting Enzyme (ACE) inhibitors or Angiotensin II Receptor Blockers (ARBs), which help relax blood vessels. Beta-blockers work by making the heart beat slower and with less force. Diuretics, sometimes called water pills, help the body remove excess sodium and water. Any decision to start, stop, or change medication must be made in consultation with a healthcare provider.