High blood pressure, also known as hypertension, is a condition in which the force of the blood against the artery walls is consistently too high. It affects approximately one-third of adults in the United States and probably similar numbers in other developed countries. High blood pressure is a significant public health concern because it is a major risk factor for heart disease, stroke, kidney disease, and other serious health problems. Early detection and management are crucial to prevent complications.
What is blood pressure?
Blood pressure measures the force exerted by circulating blood on the walls of the body’s arteries. It is expressed as two numbers: systolic pressure (the pressure when the heart beats) over diastolic pressure (the pressure when the heart is at rest). Blood pressure varies throughout the normal cardiac cycle due to the rhythmic pumping of the heart. It is created by the contraction of the heart muscle, which pushes blood through the arteries. Blood pressure is essential because it ensures that blood reaches all parts of the body, delivering oxygen and nutrients. There is a range for what is considered normal blood pressure, generally around 120/80 mmHg for adults. Blood pressure can vary throughout the body and throughout the day due to factors such as activity level, stress, and posture.
Symptoms and signs of high blood pressure in an adult
High blood pressure is often called a “silent killer” because it typically has no symptoms. However, some people may experience headaches, shortness of breath, or nosebleeds, particularly if the blood pressure is extremely high. These symptoms are not specific to high blood pressure and usually do not occur until the condition has reached a severe or life-threatening stage. So do not wait for symptoms to occur before checking your blood pressure!
Complications of high blood pressure
When blood pressure is high for a prolonged period, it can cause significant damage to the body. The heart has to work harder to pump blood, which can lead to the thickening of the heart muscle (left ventricular hypertrophy) and, eventually, heart failure. The arteries can become damaged, leading to atherosclerosis (hardening and narrowing of the arteries), which increases the risk of heart attack and stroke. High blood pressure can also damage the kidneys, eyes, and brain. Some of the damage caused by high blood pressure can be reversed with proper treatment and lifestyle changes, but some complications may be permanent.
How is high blood pressure diagnosed?
High blood pressure is diagnosed using a blood pressure cuff to measure the systolic and diastolic pressures. This test is usually done in a doctor’s office, but home monitoring may also be recommended. Blood pressure readings are reported in millimeters of mercury (mmHg). A reading of 130/80 mmHg or higher is generally considered high. However, lower levels are often recommended for people with certain medical conditions, such as diabetes. Interpreting the results involves understanding that readings can vary based on time of day and activity level, so multiple readings over time are used to confirm a diagnosis.
What is the most common cause of high blood pressure in adults?
Primary hypertension
Primary hypertension, also known as essential hypertension, is the most common cause of high blood pressure in adults. It develops gradually over many years and has no single identifiable trigger. Indeed, it is influenced by many factors, including genetics, age, diet, physical activity level, and weight. Primary hypertension typically affects adults over the age of 40 and is often diagnosed during routine health checks.
Treatment for primary hypertension includes lifestyle changes and medications. Lifestyle modifications involve adopting a healthy diet low in salt and rich in fruits and vegetables, regular physical activity, maintaining a healthy weight, limiting alcohol intake, and quitting smoking.
Common medications used to treat high blood pressure include:
- Diuretics: Help the kidneys remove excess salt and water from the body, reducing blood volume and lowering blood pressure. Examples include hydrochlorothiazide and furosemide.
- ACE inhibitors: Relax blood vessels by blocking the formation of a natural chemical that narrows blood vessels. Examples include lisinopril and enalapril.
- Angiotensin II receptor blockers (ARBs): Relax blood vessels by blocking the action of a natural chemical that narrows blood vessels. Examples include losartan and valsartan.
- Calcium channel blockers: Prevent calcium from entering the cells of the heart and blood vessel walls, resulting in lower blood pressure. Examples include amlodipine and diltiazem.
- Beta-blockers: Reduce the workload on the heart and open blood vessels, causing the heart to beat more slowly and with less force. Examples include metoprolol and atenolol.
- Renin inhibitors: Slow down the production of renin, an enzyme produced by the kidneys that starts a chain of chemical steps that increases blood pressure. An example is aliskiren.
Other common medical conditions associated with high blood pressure in adults
Chronic kidney disease
Chronic kidney disease occurs when the kidneys are damaged and unable to filter blood properly. This can cause fluid and waste buildup in the body, leading to high blood pressure. Symptoms may include fatigue, swelling, and changes in urination. Diagnosis is confirmed through blood tests and imaging studies. Distinguishing features include reduced kidney function and elevated creatinine levels.
Diabetes
Diabetes can damage blood vessels and the kidneys, leading to high blood pressure. It typically affects adults of all ages and is diagnosed through blood tests measuring blood sugar levels. Management includes blood sugar control, diet, exercise, and medications such as insulin or oral hypoglycemic agents. Distinguishing features include elevated blood glucose levels and symptoms like increased thirst and frequent urination.
Obstructive sleep apnea
Obstructive sleep apnea causes interrupted breathing during sleep, leading to increased blood pressure. Symptoms include loud snoring, daytime fatigue, and restless sleep. Diagnosis is made through sleep studies that monitor breathing patterns during sleep. Distinguishing features include episodes of stopped breathing during sleep and excessive daytime sleepiness.
Hyperthyroidism
Hyperthyroidism is an overactive thyroid that can increase heart rate and blood pressure. Symptoms include weight loss, rapid heartbeat, and nervousness. Diagnosis is confirmed through blood tests measuring thyroid hormone levels. Distinguishing features include elevated levels of thyroid hormones and symptoms like heat intolerance and tremors.
Cushing’s syndrome
Cushing’s syndrome results from excessive cortisol production, which raises blood pressure. Symptoms include weight gain, fatty deposits around the face and neck, and thinning skin. Diagnosis involves blood and urine tests and imaging studies. Distinguishing features include elevated cortisol levels and physical signs like a round face and abdominal striae.
Hyperaldosteronism
Hyperaldosteronism involves excessive production of aldosterone hormone, leading to salt and water retention and increased blood pressure. Symptoms may include muscle weakness and frequent urination. Diagnosis is confirmed through blood tests measuring aldosterone and renin levels. Distinguishing features include hypokalemia (low potassium levels) and elevated aldosterone levels.
Stress
Stress can lead to temporary increases in blood pressure. Symptoms include anxiety, headaches, and trouble sleeping. Management involves stress-reducing techniques such as relaxation exercises, counseling, and lifestyle modifications. Distinguishing features include a correlation between stressors and elevated blood pressure readings.
Obesity
Obesity increases the workload on the heart and can lead to high blood pressure. Symptoms include fatigue and shortness of breath. Management includes weight loss through diet, exercise, and behavioral interventions. Distinguishing features include a high body mass index (BMI) and associated metabolic syndrome.
Less common but serious medical conditions associated with high blood pressure in adults
Pheochromocytoma
Pheochromocytoma is a rare tumor of the adrenal glands that can cause high blood pressure. Symptoms include headaches, sweating, and rapid heartbeat. Diagnosis is confirmed through blood tests measuring catecholamines and imaging studies. Distinguishing features include episodic hypertension and elevated levels of catecholamines in the blood or urine.
Coarctation of the aorta
Coarctation of the aorta is a congenital condition in which the aorta narrows, increasing blood pressure. Symptoms include high blood pressure in the arms but low pressure in the legs and a heart murmur. Diagnosis is confirmed through imaging studies like echocardiography. Distinguishing features include differential blood pressure between the upper and lower extremities and a characteristic murmur.
Aortic dissection
Aortic dissection is a tear in the inner layer of the aorta that can cause sudden, severe chest or back pain. It requires immediate medical attention. Diagnosis is confirmed through imaging studies such as CT scans or MRI. Distinguishing features include tearing pain radiating to the back and unequal blood pressure in the arms.
Glomerulonephritis
Glomerulonephritis is inflammation of the kidney’s filtering units that can cause high blood pressure. Symptoms include blood in the urine and swelling. Diagnosis is confirmed through urine tests and kidney biopsy. Distinguishing features include hematuria (blood in urine) and proteinuria (protein in urine).
Polycystic kidney disease
Polycystic kidney disease is a genetic disorder causing cysts in the kidneys, leading to high blood pressure. Symptoms include back or side pain and blood in the urine. Diagnosis is confirmed through imaging studies like ultrasound. Distinguishing features include numerous kidney cysts and a family history of the disease.
Systemic lupus erythematosus
Systemic lupus erythematosus is an autoimmune disease that can damage organs, including the kidneys, leading to high blood pressure. Symptoms include joint pain, skin rashes, and fatigue. Diagnosis is confirmed through blood tests and clinical evaluation. Distinguishing features include a characteristic butterfly-shaped rash on the face and a positive antinuclear antibody (ANA) test.
Scleroderma
Scleroderma is a group of autoimmune diseases that causes the hardening and tightening of the skin and connective tissues, affecting blood pressure. Symptoms include skin changes and difficulty swallowing. Diagnosis is confirmed through clinical evaluation and blood tests. Distinguishing features include thickened skin, particularly on the hands and face, and Raynaud’s phenomenon.
Renovascular hypertension
Renovascular hypertension is caused by the narrowing of the arteries supplying the kidneys, leading to high blood pressure. Symptoms include sudden-onset hypertension and kidney dysfunction. Diagnosis is confirmed through imaging studies like renal artery Doppler ultrasound. Distinguishing features include a bruit (whooshing sound) over the renal arteries and refractory hypertension despite treatment.
Carcinoid syndrome
Carcinoid syndrome is a rare condition caused by a type of tumor that secretes hormones, leading to high blood pressure. Symptoms include flushing, diarrhea, and wheezing. Diagnosis is confirmed through urine tests measuring 5-HIAA and imaging studies. Distinguishing features include episodic flushing and elevated levels of serotonin metabolites.
Acromegaly
Acromegaly results from excessive growth hormone production, which causes high blood pressure. Symptoms include enlarged hands and feet and facial changes. Diagnosis is confirmed through blood tests measuring growth hormone levels and imaging studies. Distinguishing features include changes in facial structure, increased shoe and glove size, and elevated IGF-1 levels.
Takayasu arteritis
Takayasu arteritis is an inflammatory disease that affects large arteries and leads to high blood pressure. Symptoms include limb pain and fatigue. Diagnosis is confirmed through imaging studies and blood tests. Distinguishing features include diminished pulses in the arms or legs and aortic wall thickening on imaging.
Clues to aid in the differential diagnosis
Several symptoms or signs can help determine the cause of high blood pressure in an adult.
- Persistent headaches and vision changes may indicate a more severe condition like pheochromocytoma or renovascular hypertension.
- Sudden weight gain, stretch marks, and easy bruising could suggest Cushing’s syndrome.
- Excessive sweating, palpitations, and anxiety could be signs of hyperthyroidism or pheochromocytoma.
- A history of autoimmune diseases or symptoms such as joint pain and skin changes might point to conditions like systemic lupus erythematosus or scleroderma.
Advice for patients
Managing high blood pressure involves a combination of lifestyle changes and, when necessary, medication. Here are some suggestions.
Lifestyle changes
1. Adopt a healthy diet:
- Follow the DASH diet, which includes plenty of fruits, vegetables, whole grains, lean proteins, and low-fat dairy.
- Reduce sodium intake to less than 2,300 mg daily, aiming for 1,500 mg if possible.
- Limit saturated and trans fats by choosing lean meats, low-fat dairy, and cooking with healthy oils.
2. Regular physical activity:
- Aim for at least 150 minutes of moderate-intensity aerobic exercise each week, such as brisk walking, swimming, or cycling.
- Include strength training exercises at least twice weekly to improve muscle mass and overall fitness.
3. Maintain a healthy weight:
- Work towards a healthy weight through a balanced diet and regular physical activity.
- Even modest weight loss can significantly reduce blood pressure.
4. Limit alcohol consumption:
- Women should limit alcohol to one drink per day and men to two drinks per day.
- Choose lower-calorie alcoholic beverages and avoid high-sugar mixers.
5. Quit smoking:
- Seek support through smoking cessation programs or healthcare providers.
- Consider nicotine replacement therapies or prescribed medications to manage withdrawal symptoms.
6. Reduce stress:
- Practice relaxation techniques such as yoga, meditation, or deep-breathing exercises.
- Manage time effectively and engage in hobbies or activities that promote relaxation.
7. Monitor blood pressure at home:
- Use a reliable home blood pressure monitor and record readings regularly.
- Measure blood pressure at the same time each day and follow instructions for accurate readings.
8. Reduce caffeine intake:
- Limit caffeine to moderate levels and monitor its effect on your blood pressure.
9. Get regular check-ups:
- Visit your doctor regularly to monitor blood pressure and overall health.
- Adjust treatment plans based on blood pressure readings and health status.
Medications
In addition to lifestyle changes, medications may be necessary to control high blood pressure. Common medications include:
- Diuretics: Help the kidneys remove excess salt and water, reducing blood volume and lowering blood pressure. Examples include hydrochlorothiazide and furosemide.
- ACE inhibitors: Relax blood vessels by blocking the formation of a natural chemical that narrows blood vessels. Examples include lisinopril and enalapril.
- Angiotensin II receptor blockers (ARBs): Relax blood vessels by blocking the action of a natural chemical that narrows blood vessels. Examples include losartan and valsartan.
- Calcium channel blockers: Prevent calcium from entering the cells of the heart and blood vessel walls, resulting in lower blood pressure. Examples include amlodipine and diltiazem.
- Beta-blockers: Reduce the workload on the heart and open blood vessels, causing the heart to beat more slowly and with less force. Examples include metoprolol and atenolol.
- Renin inhibitors: Slow down the production of renin, an enzyme produced by the kidneys that starts a chain of chemical steps that increases blood pressure. An example is aliskiren.
When to seek urgent medical care
If, while measuring your blood pressure, you get a systolic level (the top number) of 180 mm Hg or higher or a diastolic level (the bottom number) of 120 mm Hg or higher, you should seek immediate medical attention. These levels are considered hypertensive crisis levels and may indicate a severe health risk that requires prompt intervention. Additionally, if these high readings are accompanied by symptoms such as severe headache, chest pain, shortness of breath, or vision changes, urgent medical care is required.
Summary
High blood pressure is a common and important health issue that can lead to serious complications if left untreated. Understanding the causes of high blood pressure, recognizing the symptoms and complications, and knowing how it is diagnosed is essential for effective management. The most common cause is primary hypertension, but other conditions can also contribute to high blood pressure. Identifying the underlying cause is crucial for appropriate treatment. Patients should be proactive in managing their blood pressure through lifestyle changes and medication, if necessary, to reduce the risk of complications. Regular follow-up with healthcare providers is important for monitoring and adjusting treatment plans.