Fullscript Academy

Hypertension, or high blood pressure, is one of the most prevalent chronic conditions worldwide. Despite its commonness, around half of adults with hypertension are unaware of it. This is because the condition is often asymptomatic until it progresses to a severe stage, making early detection and management critical. (World Health Organization 2023) Blood testing plays a pivotal role in both the prevention and management of hypertension. 

Traditional and functional diagnostic approaches to hypertension

Hypertension can be caused by various genetic, environmental, and lifestyle factors. Traditional diagnostic approaches often focus on measuring blood pressure and assessing common risk factors such as age, obesity, smoking, and family history. (World Health Organization 2023) However, while these are essential, they may not provide a complete picture of a patient’s cardiovascular health.

Functional diagnostic approaches offer deeper insights by evaluating the underlying causes of hypertension and identifying potential complications. These approaches include a comprehensive assessment of various biomarkers, offering a better understanding of a patient’s health and enabling more targeted treatment plans.

Age and family history, along with lifestyle factors like smoking and obesity, are major risk factors for hypertension. 

Lipid profile 

Dyslipidemia (abnormal levels of lipids in the bloodstream) is a known risk factor for hypertension. Elevated cholesterol levels, particularly low-density lipoprotein (LDL), contribute to the development of atherosclerosis—a condition characterized by the buildup of plaques in the arterial walls. This process can lead to increased vascular resistance, a key factor in hypertension. (Otsuka 2016)

Blood tests that assess lipid profiles are therefore essential in evaluating cardiometabolic disease (CMD) risk in hypertensive patients. A basic lipid profile measures:

• High-density lipoprotein cholesterol (HDL-C): Known as “good cholesterol,” higher levels of HDL-C are protective against cardiovascular disease (CVD). 

• Low-density lipoprotein cholesterol (LDL-C): Often termed “bad cholesterol,” elevated LDL-C levels are a major risk factor for atherosclerosis.

• Total cholesterol: High levels are associated with an increased risk of CVD.

• Triglycerides: Elevated triglyceride levels can contribute to the development of hypertension and are often linked with other metabolic disorders. (American Heart Association 2024)(Jung 2022)

By evaluating these markers, practitioners can identify patients at risk of CMD and implement strategies to manage both blood pressure and lipid levels effectively.

Advanced testing 

Several lipid markers have been identified as potentially having better prognostic value than standard lipid tests. These advanced markers can be highly valuable as they may be able to provide further insight into cardiovascular risk. This includes markers that represent lipoprotein particle size, like LDL particle number, and CVD risk markers, such as apolipoprotein B (apoB) and lipoprotein(a) (Lp(a)). (Feingold 2023)

Inflammation 

Inflammation plays a critical role in the development of hypertension and atherosclerosis. Chronic inflammation can lead to endothelial dysfunction, reducing the production of nitric oxide—a vital molecule for vascular health that promotes vasodilation and blood pressure regulation. (Pacinella 2022)

Several inflammatory markers can be measured to assess a patient’s risk of atherosclerosis and hypertension:

• High-sensitivity C-reactive protein (hs-CRP): Elevated hs-CRP levels are associated with an increased risk of cardiovascular events and can indicate underlying inflammation. (Carrero 2019)

• Myeloperoxidase (MPO): MPO is an enzyme linked to oxidative stress and inflammation within the arterial walls, contributing to the development of atherosclerosis. (Frangie 2022)

• Lipoprotein-associated phospholipase A2 (Lp-PLA2): This enzyme is involved in the inflammatory processes within the arteries and is considered a specific marker for atherosclerotic plaque formation. (Santoso 2020)

Incorporating these inflammatory markers into the diagnostic process helps in identifying patients with heightened cardiovascular risk due to inflammatory processes.

Renal function 

The kidneys play an important role in blood pressure regulation by controlling fluid balance and secreting hormones such as renin. Hypertension can both cause and result from renal dysfunction, creating a vicious cycle that exacerbates cardiovascular risks. (Burnier 2023)

Key blood tests for evaluating renal function in hypertensive patients include:

• Serum creatinine: Elevated levels may indicate impaired kidney function.

• Estimated glomerular filtration rate (eGFR): eGFR is a calculated measure used to estimate the filtering capacity of the kidneys. Reduced eGFR indicates renal dysfunction.

• Blood urea nitrogen (BUN): High BUN levels can suggest kidney dysfunction, particularly when correlated with creatinine levels.

• Microalbumin: The presence of albumin in the urine (microalbuminuria) is an early marker of kidney damage, often seen in hypertensive patients. It also indicates increased endothelial permeability. (Gounden 2023)

Monitoring renal function is essential in hypertensive patients, as early detection of kidney impairment can prompt interventions that prevent further progression of both hypertension and renal disease.

Adrenal and thyroid function

The adrenal and thyroid glands are integral to blood pressure regulation. The adrenal glands secrete hormones such as aldosterone, which influences sodium and water retention, directly impacting blood pressure. (Tsilosani 2022) Thyroid hormones also affect cardiovascular function by modulating heart rate and vascular resistance. (Yamakawa 2021)

Key endocrine and hormonal markers to assess include:

• Aldosterone: Elevated levels may indicate primary aldosteronism, a condition that leads to hypertension. (Tsilosani 2022)

• Renin: Low renin levels in the context of high aldosterone can point to primary aldosteronism. (Vaidya 2020)

• Cortisol: High cortisol levels, as seen in Cushing’s syndrome, can lead to secondary hypertension. (Isidori 2015)

• Thyroid-stimulating hormone (TSH) and free thyroxine (T4): These markers represent basic assessment of thyroid function, with both hyperthyroidism and hypothyroidism being potential contributors to hypertension. (Shimizu 2020)

Evaluating adrenal and thyroid function can uncover hormonal imbalances that may be driving hypertension, allowing for targeted treatment approaches.

Electrolyte imbalance can negatively impact blood pressure regulation. Encouraging electrolyte drinks in patients with low sodium, potassium, or calcium levels may be a helpful management strategy. 

Electrolyte balance

Electrolytes play a fundamental role in maintaining fluid balance, nerve function, and muscle contraction, all of which are crucial for blood pressure regulation. (National Library of Medicine n.d.) Disturbances in electrolyte levels can contribute to or exacerbate hypertension.

Important electrolytes to monitor include:

• Sodium: High sodium levels can lead to fluid retention and increased blood pressure. (Grillo 2019)

• Potassium: Low potassium levels are associated with an increased risk of hypertension, as potassium helps regulate sodium balance. (Kim 2024)

• Calcium: Alterations in calcium levels can influence vascular tone and blood pressure. (Touyz 2018)

Monitoring these electrolytes helps in managing fluid balance and identifying potential electrolyte imbalances that may need correction in hypertensive patients.

Glucose metabolism

Hypertension often coexists with other metabolic disorders, particularly those related to glucose metabolism. Insulin resistance and hyperglycemia are linked with increased cardiovascular risk and can exacerbate hypertension. (Petrie 2018)

Basic glucose metabolism markers include:

• Fasting blood sugar (FBS): Elevated levels of FBS can indicate impaired glucose tolerance or diabetes, both of which are risk factors for hypertension. (World Health Organization n.d.)

• Hemoglobin A1c (HbA1c): This marker provides an average of blood glucose levels over the previous 2–3 months and is used to diagnose and monitor diabetes. (Eyth 2023)

By evaluating glucose metabolism, healthcare providers can identify patients at risk of developing diabetes and associated hypertension, allowing for early intervention.

Nutritional markers

Nutritional status plays a vital role in cardiovascular health and blood pressure regulation. Deficiencies in certain vitamins, minerals, and antioxidants can contribute to the development and progression of hypertension.

Relevant basic nutritional markers include:

• Magnesium: Low magnesium levels are associated with increased blood pressure, as magnesium is crucial for vascular health. (Cunha 2012)

• Omega-3 index: This measures the level of omega-3 fatty acids in red blood cells, with higher levels being protective against CVD. (Superko 2013)

• Vitamin B6 and folate: These vitamins are involved in homocysteine metabolism, with deficiencies potentially leading to elevated homocysteine levels—a risk factor for atherosclerosis. (Bajic 2022)

• Vitamin C: As an antioxidant, vitamin C may help in reducing blood pressure by improving endothelial function and reducing oxidative stress. (Juraschek 2012)

• Vitamin D: Deficiency in vitamin D has been linked with increased blood pressure and cardiovascular risk. (Kheiri 2018)

• Vitamin E: The antioxidant properties of vitamin E may help improve oxidative stress and atherosclerosis. (Rizvi 2014)

Specialty nutritional laboratory markers

Testing for certain markers available through specialty labs—including organic acid and amino acid testing—can offer valuable insights into underlying metabolic and nutritional factors contributing to elevated blood pressure.

• Arginine metabolites (citrulline, ornithine, and aspartate): Markers associated with arginine metabolism provide insight into nitric oxide (NO) production—a critical regulator of vascular tone and vascular resistance. (Wiesinger 2007)

• Markers of oxidative stress (8-OHdG and pyroglutamate): 8-Hydroxy-2'-deoxyguanosine (8-OHdG) is a biomarker of oxidative DNA damage and oxidative stress which can contribute to vascular damage and cardiovascular risk. (Di Minno 2016) Pyroglutamate is associated with glutathione metabolism. Low glutathione levels are connected to oxidative stress, a key factor in endothelial dysfunction and hypertension. (Gawryluk 2010)(Stewart 2024) Elevated 8-OHdG and pyroglutamate levels may be useful markers for assessing oxidative stress in hypertensive patients.

• Metabolites of norepinephrine and epinephrine: Elevated levels of vanilmandelate (VMA) and homovanillate (HVA) indicate increased catecholamine activity, which is often linked to hypertension, particularly in individuals experiencing chronic stress or sympathetic nervous system overactivity. (Zuber 2011)

Assessing these nutritional markers can help practitioners identify and correct deficiencies that may be contributing to hypertension, thereby supporting overall cardiovascular health.

Hypertension assessment through blood testing

Blood testing offers a comprehensive approach to diagnosing and managing hypertension by providing insights into underlying causes, associated risk factors, and potential complications. By utilizing both traditional and functional diagnostic approaches, practitioners can develop more personalized treatment plans that address the multifaceted nature of hypertension, helping to improve blood pressure control and overall patient health outcomes.