Hypertension, or high blood pressure, is a common disorder where blood pressure remains abnormally elevated for a sustained period of time. Although an asymptomatic condition, when left untreated, chronic hypertension can significantly increase the risk of heart attack, stroke, heart failure, kidney disease and death, posing serious health risks to those suffering from the disease. Hypertension is the single most common contributor to death worldwide, being a root cause of stroke, congestive heart failure and kidney disease. Approximately 62% of cerebrovascular and 49% of ischemic heart disease cases are attributed to suboptimal blood pressure control. After diabetes, hypertension itself is the second most common cause of end-stage renal failure and 80% of chronic kidney disease patients develop hypertension at some point in the course of their disease.
The main function of the kidneys is to remove wastes and excess water from the body. Chronic kidney disease (CKD) is the slow loss of kidney function over time. CDK slowly gets worse over time. Approximately 60 million people globally have CKD. In the early stages, there may be no symptoms. The loss of function usually takes months or years to occur. It may be so slow that symptoms do not appear until kidney function is less than one-tenth of normal. High blood pressure is the most common cause after diabetics and accounts for most cases. However, disrupting certain nerves in the kidneys can safely and effectively lower blood pressure in patients with chronic kidney disease and hypertension. Over activity of neurons in the sympathetic – or fight or flight – nervous system is very common in patients with CKD. It not only contributes to high blood pressure and heart problems in these patients, but also to worsening of their kidney disease.
A minimally invasive procedure called renal denervation – which uses radiofrequency waves to disrupt the overactive sympathetic nerves running along the arteries in the kidneys – can lower blood pressure in individuals with hypertension and normal kidney function. In CDK patients normal blood pressure is 120/80 mmHg. Patients’ average level is 174/91 mmHg despite taking numerous antihypertensive drugs. Patients’ blood pressure readings drop considerably at one, three, six, and 12 months after the renal denervation procedure. Renal denervation does not worsen patients’ kidney function, indicating that it is safe even when CKD is present. This opens up an entirely new approach to better control blood pressure in CKD and potentially slow down progression of CKD and reduce cardiovascular risk in these patients.