Hypertension, commonly known as high blood pressure, is a widespread health issue. It is considered a disease due to its chronic and progressive nature. While it often lacks immediate symptoms, its sustained presence can inflict substantial damage on various bodily systems over time, requiring diagnosis and ongoing management.
Defining Hypertension
Hypertension refers to a persistent elevation of blood pressure within the arteries, the vessels that carry blood from the heart to the rest of the body. Blood pressure is measured using two numbers: systolic and diastolic pressure. Systolic pressure, the first number, indicates the force of blood against artery walls when the heart beats, while diastolic pressure, the second number, represents the pressure when the heart rests between beats. Measurements are expressed in millimeters of mercury (mm Hg), for example, 120/80 mm Hg.
Normal blood pressure is below 120/80 mm Hg. Elevated blood pressure, or pre-hypertension, is defined by a systolic pressure between 120 and 129 mm Hg and a diastolic pressure below 80 mm Hg. Stage 1 hypertension is diagnosed when systolic pressure is 130 to 139 mm Hg or diastolic pressure is between 80 and 89 mm Hg. Stage 2 hypertension indicates readings of 140/90 mm Hg or higher. A hypertensive crisis, a medical emergency, occurs when systolic pressure exceeds 180 mm Hg and/or diastolic pressure is above 120 mm Hg.
Hypertension is categorized into two types: primary (essential) and secondary. Primary hypertension accounts for 90-95% of cases and develops gradually without an identifiable cause, often linked to a combination of genetic and lifestyle factors. Secondary hypertension results from an underlying medical condition, such as kidney disease or adrenal gland issues.
Why Hypertension is Classified as a Disease
Hypertension is classified as a disease because of its chronic and progressive nature. It is a long-term condition that develops over months or even years, often without noticeable symptoms, earning it the moniker “silent killer.” This insidious progression allows damage to the body to occur quietly over an extended period.
The condition causes sustained high pressure on artery walls, leading to gradual deterioration of blood vessels and organs throughout the body. This progressive damage can affect the heart, kidneys, brain, and eyes, among other systems. Without proper management, hypertension persists and can lead to severe health complications. Its requirement for lifelong management, often involving medication and lifestyle adjustments, further solidifies its status as a disease.
Health Consequences of Untreated Hypertension
Untreated hypertension can lead to severe health complications affecting multiple organ systems. The persistent high pressure on artery walls causes damage and narrowing of blood vessels, impeding the flow of blood and oxygen to vital organs. This systemic impact underscores the seriousness of the condition.
Damage to the cardiovascular system is a major concern. High blood pressure strains the heart, causing the heart muscle to thicken and weaken over time, potentially leading to heart failure where the heart struggles to pump enough blood. It also contributes to coronary artery disease, narrowing the arteries that supply blood to the heart, resulting in chest pain (angina), irregular heart rhythms, or a heart attack. Furthermore, uncontrolled hypertension is a leading risk factor for stroke, which occurs when blood supply to the brain is interrupted, causing brain cells to die. Aneurysms, bulges in weakened artery walls, can form and rupture, leading to life-threatening internal bleeding.
Beyond the cardiovascular system, the kidneys are highly susceptible to damage from high blood pressure. The tiny blood vessels within the kidneys, responsible for filtering waste and excess fluid from the blood, can be impaired. This damage can lead to chronic kidney disease or even kidney failure, necessitating dialysis or a kidney transplant in severe cases. The brain is also vulnerable, with hypertension increasing the risk of cognitive decline and vascular dementia, caused by narrowed or blocked arteries limiting blood flow to the brain. Additionally, the delicate blood vessels supplying the eyes can be damaged, leading to hypertensive retinopathy, potentially causing vision problems or blindness.
Identifying and Managing Hypertension
Identifying hypertension typically involves regular blood pressure checks, which are the most reliable way to detect the condition, as it often presents without symptoms. Adults over 40 are advised to have their blood pressure checked every five years, or annually for those with risk factors. These measurements can be taken in a doctor’s office, at home using a personal blood pressure monitor, or through ambulatory 24-hour blood pressure monitoring, providing readings over a full day.
Once diagnosed, managing hypertension involves a combination of lifestyle modifications and medication, if needed. Lifestyle changes are a first-line approach for all patients. These include adopting a heart-healthy diet rich in fruits and vegetables while limiting sodium and unhealthy fats, engaging in regular physical activity (e.g., 150 minutes per week of moderate aerobic activity), maintaining a healthy weight, moderating alcohol consumption, and managing stress. These changes can help lower blood pressure and enhance the effectiveness of any prescribed medications.
When lifestyle adjustments alone are insufficient to control blood pressure, medication becomes a necessary part of the treatment plan. Several types of medications are available, such as ACE inhibitors, angiotensin-2 receptor blockers, calcium channel blockers, and diuretics, each working through different mechanisms to lower blood pressure. The goal of treatment is to reduce cardiovascular and renal complications. Ongoing medical supervision and adherence to the prescribed treatment plan are important for effectively managing hypertension and reducing the risk of serious health problems.