What is the main cause of hypertension is high blood pressure, a very common condition in older adults. Blood pressure is the physical force exerted by the blood as it pushes against the walls of the arteries. Blood pressure readings are written in two numbers separated by a line. The top number represents the systolic blood pressure and the bottom number represents the diastolic pressure. The systolic blood pressure is the pressure in the arteries as the heart contracts pushing the blood forward. The diastolic pressure is the pressure in the arteries as the heart relaxes.
Hypertension is defined as the average systolic blood pressure (SBP) or diastolic blood pressure (DBP) that is at or above the 95th percentile for gender, age, and height on three or more occasions. Stage I hypertension is more than 95% to 99% plus 5 mm Hg, and stage II hypertension is more than 99% plus 5 mm Hg. Prehypertension (formerly designated high normal BP) is defined as SBP or DBP levels that are more than the 90th percentile but less than the 95th percentile. White‐coat hypertension refers to patients with BP levels at or above the 95th percentile in a physician’s office or clinic but who are normotensive outside the clinical setting
Normal blood pressure is below 120/80, blood pressure between 120/80 and 139/89 is pre-hypertension and blood pressure 140/90 or above is considered hypertension. An elevated blood pressure means that the heart must work harder to pump blood. High blood pressure can also damage the walls of the arteries. Over time, hypertension increases the risk of heart disease, kidney disease, and stroke. It is estimated that one in three adults in America are affected by hypertension.
High blood pressure is more common in older people. At age 45, more men have hypertension than women. By age 65, this is reversed and more women are affected. People with diabetes have a greater risk of hypertension than those without diabetes. Having a close family member with high blood pressure also increases your risk of developing it. About 60% of all people with diabetes also have hypertension.
Prehypertension means that your blood pressure falls just above the normal level, corresponding to a systolic pressure between 120 and 139 or a diastolic pressure of 80 to 89. About one-fourth of Americans have prehypertension, and they have two times the risk of heart disease compared with those who have lower blood pressures. Lifestyle changes can help many people with prehypertension lower their blood pressure.
Factors that increase your blood pressure can cause prehypertension. Medications such as birth control pills, cold remedies, decongestants, over-the-counter pain relievers, and some prescription drugs may cause a temporary rise in blood pressure. The buildup of fatty deposits in the arteries (atherosclerosis) can also lead to prehypertension. Other conditions that may lead to prehypertension include the following:
- Obstructive sleep apnea
- Kidney disease
- Adrenal disease
- Thyroid disease
There are no symptoms caused by prehypertension. The only way to keep track of your blood pressure is to visit your doctor regularly and have your blood pressure checked.
You are considered to have hypertension if your blood pressure measurements are 140/90 or higher, for either of the two numbers. At this level of blood pressure you may not have any symptoms. When blood pressure reaches 180/110 or higher, a serious condition known as a malignant hypertension may occur. This can lead to stroke, kidney damage, heart attacks, or loss of consciousness. If you measure your blood pressure and it is this high, rest a few minutes and measure again. If it remains high, call 911.
Malignant Hypertension Causes
High blood pressure is the main cause of malignant hypertension. Skipping doses of blood pressure medications can also lead to malignant hypertension. The following are medical conditions that may cause malignant hypertension:
- Kidney disease
- Collagen vascular disease
- Spinal cord injuries
- Tumor of the adrenal gland
- Birth control pills
- Illegal drugs (cocaine)
Malignant Hypertension Symptoms
The primary symptoms of malignant hypertension is a blood pressure of 180/120 or higher and signs of organ damage. Other symptoms of malignant hypertension include bleeding and swelling of blood vessels in the retina, anxiety, nosebleeds, severe headache, and shortness of breath. Malignant hypertension may cause brain swelling, but this symptom is very rare.
Abnormally elevated pressure in the pulmonary circulation is referred to as pulmonary hypertension. This condition affects the arteries in the lungs and the right side of the heart.
Pulmonary Hypertension Causes
Pulmonary hypertension is caused by changes in the cells that line the pulmonary arteries. These changes cause the walls of the arteries to become stiff and thick, extra tissue may also form. This can reduce or block blood flow through the blood vessels. Increased blood pressure is then caused because it is harder for blood to flow. Pulmonary hypertension can be an associated condition with scleroderma, sarcoidosis, pulmonary embolism, and dermatomyositis.
Pulmonary Hypertension Symptoms
Symptoms of pulmonary hypertension may not present themselves for months or years. Later on, symptoms become worse. Symptoms of pulmonary hypertension may include:
- Shortness of breath
- Chest pain or pressure
- Swelling in the ankles, legs, and abdomen
- Bluish color to the lips and skin
- Racing pulse or heart palpitations
The portal venous system contains veins coming from the stomach, intestine, spleen, and pancreas. These veins merge into the portal vein, which branches into smaller vessels and travel through the liver. Portal hypertension occurs when there is an increase in the blood pressure within the portal venous system. When the vessels in the liver are blocked due to liver damage, blood cannot flow properly through the liver. This causes high blood pressure in the portal system.
Portal Hypertension Causes
Cirrhosis of the liver is the most common cause of portal hypertension. In cirrhosis, the scar tissue (from the healing of liver injury caused by hepatitis, alcohol, or other liver damage) blocks the flow of blood through the liver. Blood clots in the portal vein, blockages of the veins that carry blood from the liver to the heart, parasitic infection (schistosomiasis), and focal nodular hyperplasia are also causes of portal hypertension.
Portal Hypertension Symptoms
Symptoms of portal hypertension include the following:
- Gastrointestinal bleeding, which can cause black, tarry stools or blood in stools, or vomiting of blood
- Ascites (fluid in the abdomen)
- Encephalopathy or confusion
- Reduced levels of platelets (blood cells that help form blood clots)
High Blood Pressure in Children
Although it’s most common in older adults, hypertension can also affect children. The normal blood pressure for a child is dependent upon the child’s age, gender, and height. Your doctor can tell if your child’s blood pressure is abnormal. Children are at higher risk for hypertension if they are overweight, African-American, or if they have a family history of the condition. Children with high blood pressure may benefit from the DASH diet and taking medications. Children with high blood pressure should also maintain a healthy weight and avoid tobacco smoke.
Causes of Hypertension
Blood pressure is given as a reading of two numbers, such as 110/70. The higher number (systolic) is the pressure when the heart beats. The diastolic, or lower number shows the pressure between the heartbeats, while the relaxed heart is refilling with blood. Normal blood pressure readings are lower than 120/80. The cause of most hypertension is unknown. Occasionally, conditions of the kidney or adrenal gland are the cause of high blood pressure.
There are several factors that may cause high blood pressure, but the exact cause is unknown. The following factors may increase one’s risk for high blood pressure:
- Overweight or obesity
- Lack of physical activity
- Too much salt consumption
- Too much alcohol consumption (more than 1 to 2 drinks per day)
- Older age
- Family history of high blood pressure
- Chronic kidney disease
- Adrenal and thyroid disorders
- Sleep apnea
African-Americans are at greater risk of developing hypertension than people of other races. African-Americans develop high blood pressure earlier in life and have more difficulty achieving blood pressure goals. Some studies suggest that African-Americans may be more sensitive to salt than other races. For those who are genetically prone to salt sensitivity, a small amount (half-teaspoon) of salt can raise blood pressure by 5 mm Hg. Dietary factors and being overweight can also raise blood pressure.
Sodium, a chemical found in salt, raises blood pressure by promoting the retention of fluid by the body. This increases the workload on the heart. The American Heart Association recommends an upper daily limit for sodium consumption of 1,500 mg. Checking food labels and menus can help you calculate how much sodium you are consuming. Processed foods are particularly high in sodium and make up about 75% of our sodium intake. Among these, lunch meats and canned soups have some of the highest levels of dietary sodium.
Causes by Stress
Stress leads to temporary elevations of blood pressure, but there is no proof that stress causes ongoing high blood pressure. Stress may have an indirect effect on blood pressure since it can influence other risk factors for heart disease. People who are under stress tend to engage more in unhealthy habits like poor nutrition, alcohol use, and smoking, all of which can play a role in the development of high blood pressure and heart disease.
Causes by Weight
Being overweight increases the risk of getting hypertension and increases the workload required of your heart. Diets designed to control blood pressure are often designed to reduce calories as well. Most of these diets require decreasing consumption of fatty foods and sugars while increasing your intake of lean protein, fiber, fruits, and vegetables. A weight loss of just 10 pounds can make a significant difference in your blood pressure.
Causes by Alcohol
Drinking too much alcohol is a risk factor for high blood pressure. The American Heart Association guidelines recommend the consumption of no more than two alcoholic drinks per day for men and no more than one drink a day for women. One drink is defined as one 12-ounce beer, 4 ounces of wine, 1.5 ounces of 80-proof spirits, or 1 ounce of 100-proof spirits. Adults who consume more than three drinks in one sitting temporarily increase their blood pressure. However, binge drinking can lead to long-term increased blood pressure.
Causes by Caffeine
Caffeine can bring on the jitters, but there is no evidence that it can cause long-term hypertension. However, a caffeinated beverage might bring on a temporary rise in blood pressure. It is possible that caffeine could block a hormone that helps keep arteries widened, which causes blood pressure to rise. It is also possible that caffeine causes adrenal glands to release more adrenaline, causing blood pressure to increase. The exact reason why caffeine causes increased blood pressure is unknown.
Causes by Medication
Certain medications contain ingredients that can elevate blood pressure. Cold and flu medications that contain decongestants are one example of drugs that raise blood pressure. Other kinds of medicines that can raise blood pressure are steroids, diet pills, birth control pills, non-steroidal anti-inflammatory drugs (NSAIDs), pain relief medications, and some antidepressants. Talk to your doctor about the medications or supplements you are taking that might affect your blood pressure.
|Leisure-Time Physical Activity||Activities that one participates in during their free time that results in substantial energy expenditure. These activities include structured exercise as well as walking, hiking, gardening, sport, and dance.|
|Occupational Physical Activity||Activities that are associated with the performance of a job which might include might include walking, hauling, lifting, pushing, carpentry, shoveling, and packing boxes.|
|Sedentary Behavior||Lack of physical activity. Refers to activities that do not increase energy expenditure above the resting level and has been operationally defined as activities with energy expenditures ≤ 1.5 METs while in a sitting or reclined posture (e.g. sleeping, watching television, video gaming, computer use).|
|Aerobic Exercise||A form of exercise that involves the use of large muscle groups to perform repetitive activities that result in increases in heart rate and energy expenditure (e.g. walking; cycling).|
|Resistance Training||A form of exercise designed to improve muscular strength and/or endurance wherein physical effort is performed against an opposing force that elicits resistance to induce muscular contraction, typically at a high intensity of effort for a short duration of time (e.g. weight lifting).|
|Cardiorespiratory Fitness||The ability of the circulatory and respiratory systems to supply oxygen during sustained physical activity.|
|Muscular Strength||The amount of external force that a skeletal muscle can exert.|
|Muscular Endurance||The ability of muscle groups to exert external force for many repetitions or successive exertions.|
Symptoms of Hypertension
Hypertension may not produce any symptoms, even if you have had it for years. That’s why it is sometimes referred to as a “silent killer.” It’s estimated that 1 out of every 5 people with high blood pressure aren’t aware that they have this major risk factor for strokes and heart attacks. If not properly treated, high blood pressure can damage the heart and circulation, lungs, brain, and kidneys without causing noticeable symptoms. Symptoms of high blood pressure may be present in those who have an extremely high blood pressure. Symptoms of extremely high blood pressure include the following:
- Severe headaches
- Vision problems
- Chest pain
- Difficulty breathing
- Irregular heartbeat
- Blood in the urine
- Pounding in the chest, neck, or ears
Diagnosis of Hypertension
How a blood pressure test works
- A blood pressure reading is taken with a pressure cuff (sphygmomanometer).
- During the test, the cuff is placed around the upper arm before being manually or electronically inflated.
- Once inflated, the cuff compresses the brachial artery, momentarily stopping blood flow.
- Next, air in the cuff is slowly released while the person performing the measurement listens with a stethoscope or monitors an electronic readout.
Watch an interactive animation of a manual blood pressure test, including the sounds that a medical professional hears as the blood moves through the brachial artery in your arm.
Your blood pressure reading is recorded as two numbers:
- Systolic blood pressure (the top number) — indicates how much pressure your blood is exerting against your artery walls during heartbeats.
- Diastolic blood pressure (the bottom number) — indicates how much pressure your blood is exerting against your artery walls while the heart is resting between beats.
- If your blood pressure is normal (less than 120/80 mm Hg), your blood pressure should be screened during regular healthcare visits at least once every two years for anyone 20 years of age or older.
If your blood pressure reading is higher than normal
- Your doctor may take several readings over time and/or have you monitor your blood pressure at home before diagnosing you with high blood pressure.
- A single high reading does not mean that you have high blood pressure. But, if your readings continue to stay high, your doctor will most likely want you to begin a treatment program.
If you are diagnosed with high blood pressure
- Your doctor may recommend monitoring your blood pressure numbers at home in addition to your regular healthcare visits.
- Your doctor will also likely recommend a treatment plan that includes lifestyle changes and, if needed, prescription medication.
- If the clinic blood pressure is 140/90 mmHg or higher, offer ambulatory blood pressure monitoring (ABPM) to confirm the diagnosis of hypertension.
- When using ABPM to confirm a diagnosis of hypertension, ensure that at least two measurements per hour are taken during the person’s usual waking hours (for example, between 08:00 and 22:00).
Use the average value of at least 14 measurements taken during the person’s usual waking hours to confirm a diagnosis of hypertension.
When using home blood pressure monitoring (HBPM) to confirm a diagnosis of hypertension, ensure that
- for each blood pressure recording, two consecutive measurements are taken, at least 1 minute apart and with the person seated and
- blood pressure is recorded twice daily, ideally in the morning and evening and
- blood pressure recording continues for at least 4 days, ideally for 7 days. Discard the measurements taken on the first day and use the average value of all the remaining measurements to confirm a diagnosis of hypertension.
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