Blood pressure is the force exerted by circulating blood against artery walls. This measurement, which consists of systolic and diastolic readings, is a fundamental indicator of cardiovascular health. Recent research has established a clear relationship between infection with the SARS-CoV-2 virus (COVID-19) and fluctuations in blood pressure, including the development of new high blood pressure, known as hypertension. Understanding the mechanisms behind these changes is important for individuals who have recovered from the infection. This article explains how the virus can impact the body’s blood pressure regulation.
The Immediate Connection: Acute Blood Pressure Changes
During the acute phase of COVID-19, typically the first few weeks of illness, the body’s systemic response to the virus can cause temporary, but sometimes dramatic, changes in blood pressure. A significant factor is the body’s inflammatory response, often characterized by a release of signaling proteins called cytokines. This intense, widespread inflammation can disrupt the normal function of microvessels, contributing to temporary blood pressure instability.
The physical stress of fighting a severe infection also triggers the release of stress hormones like cortisol and adrenaline. This hormonal surge activates the sympathetic nervous system, commonly known as the “fight or flight” response, which naturally constricts blood vessels and increases heart rate, leading to a temporary rise in blood pressure.
Moreover, symptoms such as persistent fever and reduced fluid intake due to illness can lead to dehydration and changes in fluid balance. These physiological shifts require the body to adjust blood flow, which may result in elevated pressure readings until the acute infection resolves. These short-term changes are a reaction to the body’s overall state of distress and often subside as the person recovers from the illness. However, for those with pre-existing conditions, this acute strain can still pose a significant risk to the heart and blood vessels.
Endothelial Damage and the Risk of Chronic Hypertension
Beyond the immediate effects of acute illness, the SARS-CoV-2 virus can initiate long-term physiological changes that contribute to sustained high blood pressure. The virus gains entry to cells by binding to a specific protein on the cell surface, which is an enzyme that regulates the body’s blood pressure control system. This system, known as the renin-angiotensin system, is responsible for balancing blood vessel constriction and relaxation.
When the virus binds to the enzyme, it reduces the enzyme’s presence on the surface of blood vessel cells, a process called downregulation. This disruption shifts the balance of the blood pressure control system toward a state that promotes vessel tightening. Specifically, the protective arm of the system, which normally works to relax blood vessels, is suppressed, leaving the dominant arm to cause vasoconstriction. This imbalance results in a sustained increase in blood pressure.
A related effect is damage to the endothelium, the delicate inner lining of all blood vessels. The virus directly or indirectly causes injury to this lining, which is responsible for keeping vessels flexible and open. Damage to the endothelium leads to chronic inflammation and a loss of flexibility, causing the vessels to become stiffer and less responsive. This condition, known as endothelial dysfunction, is a fundamental driver of chronic hypertension.
Studies tracking individuals six months after infection have shown that new-onset hypertension affected approximately 21% of those who were hospitalized and around 11% of those who were not. This data suggests that the viral infection can trigger persistent hypertension, even in people without a prior history of the condition. The combination of sustained chronic inflammation and structural damage to the vasculature explains why high blood pressure can become a lasting health concern for some survivors.
Monitoring and Management Strategies
For individuals who have recovered from COVID-19, especially those with pre-existing conditions, proactive monitoring of blood pressure is important. Home blood pressure monitoring is a practical way to track readings consistently and provide accurate data to a healthcare provider. It is recommended to take readings at least twice a day, in the morning and evening, for a complete picture of blood pressure trends.
Individuals should be aware of potential signs that may signal persistent high blood pressure, such as frequent headaches, dizziness, or chest discomfort, and seek medical attention if these symptoms occur. Lifestyle modifications remain a powerful tool for regulating blood pressure post-infection:
- Adopting a diet that is low in sodium.
- Engaging in regular physical exercise.
- Maintaining a healthy body weight.
- Managing stress through techniques like meditation or counseling, as chronic stress can independently elevate blood pressure.
For those already on medication, regular check-ups with a physician are necessary to ensure the dosage remains appropriate for managing any new or persistent hypertension.