What are the causes of Hypertension (High Blood Pressure)?

From the Guidelines

Hypertension is primarily caused by a combination of genetic and lifestyle factors, with lifetime risk exceeding 80% in U.S. adults. Given the high prevalence of hypertension, it is essential to understand its causes to develop effective prevention and management strategies. Genetic predisposition plays a significant role, as individuals with a family history of high blood pressure are more likely to develop the condition 1. Lifestyle factors that contribute to hypertension include poor dietary habits, particularly high sodium intake, excessive alcohol consumption, physical inactivity, obesity, and chronic stress. Age is also a factor, as blood vessels naturally lose elasticity over time, increasing the risk of hypertension. Certain medical conditions can cause secondary hypertension, including kidney disease, adrenal gland disorders, thyroid problems, sleep apnea, and certain congenital blood vessel defects. Medications such as oral contraceptives, decongestants, certain pain relievers, and some prescription drugs can also raise blood pressure.

Some key factors that contribute to the development of hypertension include:

• Genetic predisposition
• Poor dietary habits, particularly high sodium intake
• Excessive alcohol consumption
• Physical inactivity
• Obesity
• Chronic stress
• Certain medical conditions, such as kidney disease and thyroid problems
• Medications, such as oral contraceptives and certain pain relievers

According to the 2020 U.S. Department of Veterans Affairs/U.S. Department of Defense clinical practice guideline, hypertension is a common health problem in both men and women, with an estimated 72 million adult Americans having hypertension 1. The guideline also highlights the importance of routine screening to diagnose hypertension, particularly in younger patients and African American persons, who may be at higher risk of developing complications. Understanding the causes of hypertension is crucial for developing effective prevention and management strategies, which can help reduce the long-term morbidity and mortality associated with the condition.

From the FDA Drug Label

Elevated systolic or diastolic pressure causes increased cardiovascular risk, and the absolute risk increase per mmHg is greater at higher blood pressures, so that even modest reductions of severe hypertension can provide substantial benefit The largest and most consistent cardiovascular outcome benefit has been a reduction in the risk of stroke, but reductions in myocardial infarction and cardiovascular mortality also have been seen regularly

Hypertension causes increased cardiovascular risk, including:

• Stroke
• Myocardial infarction
• Cardiovascular mortality 2 3

From the Research

Hypertension Causes

• Hypertension is caused by increased cardiac output and/or increased peripheral resistance 4
• The various mechanisms affecting cardiac output/peripheral resistance involved in the development of essential hypertension include:
  • Genetics
  • Sympathetic nervous system overactivity
  • Renal mechanisms: excess sodium intake and pressure natriuresis
  • Vascular mechanisms: endothelial cell dysfunction and the nitric oxide pathway
  • Hormonal mechanisms: the renin-angiotensin-aldosterone system (RAAS)
  • Obesity, obstructive sleep apnea (OSA)
  • Insulin resistance and metabolic syndrome
  • Uric acid
  • Vitamin D
  • Gender differences
  • Racial, ethnic, and environmental factors
• Maximum association of hypertension is found with sympathetic overactivity which is directly or indirectly involved in different mechanisms of hypertension including RAAS, OSA, obesity, etc. 4
• High blood pressure is a major modifiable risk factor for all clinical manifestations of coronary artery disease (CAD) 5
• The lowest systolic and the lowest diastolic pressures are associated with the lowest risk for developing CAD 5
• Pathophysiological mechanisms of blood pressure as a risk factor for CAD are complex and include the influence of blood pressure as a physical force on the development of the atherosclerotic plaque, and the relationship between pulsatile hemodynamics/arterial stiffness and coronary perfusion 5

Risk Factors

• High sodium intake
• Low potassium intake
• Obesity
• Alcohol consumption
• Physical inactivity
• Unhealthy diet 6
• Increased left ventricular ejection force and hypertension and its association with increased basal sympathetic activity - cortical connections 4

Relationship with Cardiovascular Disease

• Hypertension is the leading cause of cardiovascular disease and premature death worldwide 6
• High blood pressure is associated with the strongest evidence for causation of cardiovascular disease (CVD) and it has a high prevalence of exposure 7
• Large cohort studies have demonstrated that high BP is an important risk factor for heart failure, atrial fibrillation, chronic kidney disease, heart valve diseases, aortic syndromes, and dementia, in addition to coronary heart disease and stroke 7