High blood pressure, also known as hypertension, significantly reduces life expectancy. That is because elevated blood pressure strains the blood vessels. Over time, hypertension leads to blood vessels damages, organs dysfunction and bodily deterioration. Similar to a house with a high water pressure, a human body with a high blood pressure is at a higher risk of leaks which lowers its life expectancy.
Blood Pressure Classifications
The American Heart Association classifies blood pressure as follows:
- Normal Blood Pressure:
- Systolic Blood Pressure: Less than 120 mmHg
- Diastolic Blood Pressure: Less than 80 mmHg
- Elevated Blood Pressure:
- Systolic Blood Pressure: 120-129 mmHg
- Diastolic Blood Pressure: Less than 80 mmHg
- Hypertension (High Blood Pressure):
- Stage 1 Hypertension:
- Systolic Blood Pressure: 130-139 mmHg
- Diastolic Blood Pressure: 80-89 mmHg
- Stage 2 Hypertension:
- Systolic Blood Pressure: 140 mmHg or higher
- Diastolic Blood Pressure: 90 mmHg or higher
- Stage 1 Hypertension:
Hypertension Health Risks
Hypertension significantly increases the risk of dying from liver diseases1, fall2, diabetes, cardiovascular diseases3, kidney diseases4, cancer5, chronic lower respiratory diseases6, influenza and pneumonia7. Specifically, compared to individuals with normal blood pressure, individuals with elevated blood pressure are:
- 56% more likely to dies from liver diseases,
- 50% more likely to dies from a fall,
- 24% more likely to dies from diabetes,
- 16% more likely to dies from cardiovascular diseases,
- 16% more likely to dies from kidney diseases,
- 10% more likely to dies from cancer,
- 10% more likely to dies from chronic lower respiratory diseases and
- 10% more likely to dies from influenza.
Those risks are approximately two-fold higher for individuals with stage 1 hypertension and three-fold higher for individuals with stage 2 hypertension. The sections below present the underlying mechanisms that explain why individuals with elevated blood pressure have lower life expectancy .
How Hypertension Affects the Risk of Liver Diseases
Hypertension contributes to the development of liver diseases and lowers life expectancy through the following mechanisms:
- Portal Hypertension: The liver receives nutrient-rich blood supply from the portal vein. When the portal vein is subjected to elevated pressure for an extended period, it becomes enlarged and prone to rupture. Rupture of the portal vein is a life-threatening event.
- Impaired Blood Flow: Hypertension disrupts the normal blood flow within the liver. Consequently, the provision of oxygen and nutrients to liver cells is compromised and results in tissue damage and liver dysfunction.
- Hepatic Fibrosis and Cirrhosis: Chronic hypertension promotes the development of hepatic fibrosis which is characterized by the excessive accumulation of scar tissue in the liver. Over time, the accumulation of scar tissue progresses to cirrhosis, a condition where the liver becomes severely scarred and loses its normal structure and function.
- Non-Alcoholic Fatty Liver Disease: Hypertension is often associated with metabolic disorders such as obesity, insulin resistance and dyslipidemia. The combination of hypertension and metabolic abnormalities contribute to the development of non-alcoholic fatty liver disease which is characterized by the accumulation of fat in the liver that hinders its function.
- Increased Oxidative Stress and Inflammation: Hypertension promotes both chronic oxidative stress and low-grade inflammation throughout the body. As a result, Hypertension causes cellular damages that compromise the function of all organs, including the liver.
How Hypertension Affects the Risk of Fall
Hypertension increases the risk of falls and lowers life expectancy through the following mechanisms:
- Orthostatic Hypotension: Hypertension is associated with orthostatic hypotension which is characterized by a drop in blood pressure when standing up. This sudden decrease in blood pressure upon standing causes dizziness, lightheadedness and increases the risk of fall.
- Impaired Cerebral Blood Flow: Hypertension leads to vascular changes associated with a reduced blood flow to the brain which affect cognitive functions, balance and gait control. Therefore, individuals are more susceptible to falls. Impaired blood flow to the brain also increases the risk of transient ischemic attacks or strokes, which can cause sudden changes in mobility and balance.
- Impaired Muscle Blood Flow: Chronic hypertension causes damage to blood vessels and impairs circulation. This results in muscle weakness, impaired coordination and compromised balance, which increases the risk of falls. For example, hypertension is a significant risk factor for atherosclerosis which is characterized by the buildup of fatty deposits (plaques) in the arteries. Atherosclerosis affects blood flow to the legs which can cause intermittent claudication, a condition characterized by leg pain and muscle weakness that impairs mobility and balance.
- Vision Problems: Hypertension is associated with damages to the blood vessels in the retina. Impaired blood supply to the retina affects visual acuity, balance and depth perception which increases the risk of falls.
How Hypertension Affects the Risk of Complications from Diabetes
Hypertension increases the risk of complications associated with diabetes and lowers life expectancy through the following mechanisms:
- Cardiovascular Disease: Hypertension is a significant risk factor for the development of cardiovascular disease, including coronary artery disease, heart attack and stroke. Diabetes also increases the risk of cardiovascular complications. When both conditions coexist, the risk of cardiovascular events increases exponentially.
- Microvascular Damage: Hypertension and diabetes both contribute to damage to blood vessels throughout the body. Specifically, prolonged hypertension and hyperglycemia lead to the narrowing and blockage of blood vessels and small blood vessels such as the ones present in extremities, the retina and the kidneys are especially prone to blockage. Therefore, prolonged hypertension and hyperglycemia often results in complications such as diabetic neuropathy, retinopathy and nephropathy.
- Kidney Disease: Both hypertension and diabetes are risk factors for chronic kidney disease as both conditions damage the delicate blood vessels in the kidneys and impairs their filtering function. Therefore, when both conditions coexist, the risk of kidney diseases increases exponentially.
- Poor Glycemic Control: Hypertension makes it challenging to maintain optimal blood sugar levels as hypertension interferes with insulin sensitivity and glucose metabolism. Poorly controlled blood sugar level increases the risk of diabetes-related complications.
- Increased Inflammation and Oxidative Stress: Hypertension and diabetes are associated with increased inflammation and oxidative stress throughout the body. These processes cause systemic tissue damages and impair all organs’ functions.
How Hypertension Affects the Risk of Cardiovascular Diseases
Hypertension increases the risk of developing cardiovascular diseases and lowers life expectancy through the following mechanisms:
- Increased Stress on Blood Vessels: Hypertension damages the inner lining of blood vessels. Specifically, hypertension causes the hardening of blood vessels which makes them prone to rupture. Moreover, hypertension leads to the formation of plaques which narrow blood vessels and restrict blood flow to vital organs. As a result, the risk of cardiovascular diseases increases for people living with hypertension.
- Increased Risk of Blood Clots: Hypertension disrupts the balance between clotting and anticoagulant factors in the blood which increases the risk of blood clot formation. These clots can partially or completely block blood vessels, leading to conditions such as deep vein thrombosis, pulmonary embolism or cardiovascular events like heart attacks and strokes.
- Increased Cardiac Workload: Hypertension requires the heart to work harder to pump blood. This increased workload on the heart leads to thickening and enlargement of the heart muscle. Over time, the heart becomes less efficient in pumping blood which leads to cardiovascular problems such as heart failure and arrhythmia.
- Renal Damage: Chronic hypertension damages the blood vessels in the kidneys which leads to impaired kidney functions. In turn, kidney dysfunction causes increased blood pressure. Therefore, hypertension that creates renal damage creates a vicious circle that increases the risk of cardiovascular complications.
- Systemic Inflammation: Hypertension is associated with chronic low-grade inflammation in the body. The inflammatory response triggered by hypertension promotes the development of atherosclerosis and endothelial dysfunction.
How Hypertension Affects the Risk of Kidney Diseases
Hypertension contributes to the development and progression of kidney diseases and lowers life expectancy through the following mechanisms:
- Damage to the Renal Vasculature: Hypertension causes damage to the blood vessels in the kidneys. Prolonged elevated blood pressure leads to thickening and narrowing of the blood vessels, reducing blood flow to the kidneys and impairing their ability to filter waste products and maintain proper fluid and electrolyte balance.
- Glomerular Damage: The glomeruli are tiny blood vessels within the kidneys responsible for filtering waste products from the blood. Hypertension damages the delicate structures of the glomeruli, leading to impaired filtration function.
- Increased Pressure in the Kidney Tubules: Hypertension increases pressure within the kidney tubules, which are responsible for reabsorbing water and important substances from the filtrate. As a result, the increased pressure disrupts the normal functioning of the tubules, affecting the reabsorption and excretion processes. Over time, this leads to abnormalities in electrolyte balance and fluid retention.
- Activation of the Renin-Angiotensin-Aldosterone System: Hypertension activates the Renin-Angiotensin-Aldosterone System (RAAS), a hormonal system that regulates blood pressure and fluid balance. Consequently, the activation of the RAAS leads to the release of substances that constrict blood vessels and promote inflammation in the kidneys. Therefore, the chronic activation of the RAAS contribute to the development of kidney diseases.
- Inflammation and Oxidative Stress: Hypertension is associated with chronic low-grade inflammation and oxidative stress which causes cellular damage throughout the body, including the kidneys.
- Diabetes: Hypertension and diabetes often coexist. Diabetes is a significant risk factor for the development of kidney diseases and the combination of hypertension and diabetes can exacerbate kidney damages.
How Hypertension Affects the Risk of Cancer
Hypertension contributes to the development and progression of cancer and lowers life expectancy through the following mechanisms:
- Chronic Inflammation: Hypertension is associated with chronic low-grade inflammation throughout the body. Inflammation is an immunological process that promotes the renewal of damaged cells. However, inflammation also favours the initiation and progression of cancer as it promotes the growth and spread of all cells, including cancer cells.
- Oxidative Stress: Hypertension leads to increased oxidative stress, which occurs when there is an imbalance between the production of reactive oxygen species (ROS) and the body’s ability to neutralize them. As a result, oxidative stress damages cells and DNA, leading to mutations and genetic alterations that increase the risk of cancer.
- Angiogenesis: Hypertension influences the process of angiogenesis, which is the formation of new blood vessels. Chronic hypertension leads to an abnormal and excessive formation of blood vessels. Angiogenesis plays a critical role in tumor growth and metastasis. As such, hypertension provides a favourable environment for tumor growth and progression.
- Endothelial Dysfunction: Hypertension causes dysfunction of the endothelium, the inner lining of blood vessels. Dysfunction of the endothelium leads and impaired immune response. As a result, risk of cancer increases as endothelial dysfunction compromises the immune system’s ability to detect and destroys abnormal cancer cells.
- Hormonal Factors: Hormonal imbalances associated with hypertension, such as elevated levels of insulin and aldosterone, stimulate cell proliferation and angiogenesis which can contribute to tumor growth.
- Shared Risk Factors: Hypertension shares several risk factors with cancer, including obesity, unhealthy diet, physical inactivity and tobacco use. These lifestyle factors increase the risk of cancer in individuals with hypertension.
How Hypertension Affects the Risk of Chronic Lower Respiratory Diseases
Hypertension contributes to the development and progression of chronic lower respiratory diseases (CLRD) and lowers life expectancy through the following mechanisms:
- Systemic Inflammation: Hypertension is associated with chronic low-grade inflammation throughout the body, including the respiratory system. The chronic inflammation associated with hypertension contributes to the development and worsening of respiratory conditions such as chronic obstructive pulmonary disease (COPD) and asthma.
- Endothelial Dysfunction: Hypertension causes dysfunction of the endothelium, the inner lining of blood vessels. Endothelial dysfunction leads to impaired blood flow and oxygen delivery to the lungs, which contributes to the development or exacerbation of respiratory diseases.
- Vascular Remodeling: Hypertension leads to structural changes in the blood vessels. This remodeling affects the small blood vessels in the lungs, leading to reduced blood flow, impaired oxygen exchange and increased resistance in the pulmonary circulation. These changes contribute to the development of pulmonary hypertension and can exacerbate existing respiratory conditions.
- Impaired Gas Exchange: Hypertension affects the gas exchange process in the lungs which results in reduced lung function and an increased risk of respiratory diseases.
How Hypertension Affects the Risk of Influenza and Pneumonia
Hypertension contributes to the risk of contracting influenza or pneumonia and lowers life expectancy through the following mechanisms:
- Weakened Immune Response: Hypertension weakens the immune response and reduces the body’s ability to fend off viral and bacterial infections that underlie influenza and pneumonia.
- Impaired Lung Function: Hypertension leads to changes in the structure and function of blood vessels in the lungs. This results in reduced oxygen exchange and impaired lung function. When lung function is compromised, it becomes more difficult for the respiratory system to clear pathogens and mount an effective defence against infections.
- Comorbidities: Individuals with hypertension often have other underlying health conditions, such as obesity, diabetes, or cardiovascular disease, which increases the risk of both influenza and pneumonia. These comorbidities can weaken the immune system, impair lung function and increase the susceptibility to respiratory infections.
Blood pressure affects the body in many ways and maintaining normal blood pressure is crucial to overall health. Accordingly, controlling blood pressure is instrumental to preserving life expectancy. Adopting a healthy diet, engaging in regular physical activity, maintaining a healthy weight, managing stress, limiting alcohol consumption and adhering to prescribed medications all contribute to the maintenance of a normal blood pressure. Notably, every improvement in blood pressure towards the normal range carries associated improvement of life expectancy.
Predicting life expectancy is complex and needs to take many factors into consideration. Youlldie allows to visualize how blood pressure interacts with other factors like gender, race, world region, income, education, alcohol, tobacco, physical activity, sleep, body mass index and family history to statistically predict life expectancy.
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