Why PKD Leads to Hypertension
Around 50–70% of people with PKD develop hypertension, or high blood pressure.¹ Why is that?
There are three main causes:
- PKD damages cilia, so they’re less effective at sensing blood flow and activating processes that lower blood pressure.
- PKD damages the Renin-Angiotensin-Aldosterone System (RAAS), the hormone system that regulates blood pressure.
- PKD activates the Sympathetic Nervous System (SNS), causing elevated epinephrine that correlates with higher blood pressure.
1: PKD Damages Cilia
PKD is a ciliopathy: a disease of the cilia.
Cilia are microscopic, hair-like sensors inside a blood vessel.
Healthy cilia sense the flow of blood and signal to the surrounding smooth muscle cells to constrict or relax to raise or lower blood pressure. As blood flows along the inside of the blood vessels, healthy cilia sense how fast it’s flowing. If it’s flowing too fast, cilia sends a signal to the surrounding smooth muscle cells to relax, which lowers blood pressure.
PKD damages cilia, so they can’t sense blood flow or signal as well. The smooth muscle cells surrounding the blood vessels don’t receive a strong and steady message to relax, so blood pressure rises.
2: PKD Damages the Renin-Angiotensin-Aldosterone System (RAAS)
The Renin-Angiotensin-Aldosterone System (RAAS) is the hormone system that regulates blood pressure.
People with PKD tend to have higher levels of the hormone renin due to renal ischemia, the death of kidney cells from being crushed by cysts.
Higher levels of renin set off a chain of events, including higher levels of angiotensin and aldosterone, which lead to sodium retention in the blood. Sodium retention thickens blood, making it harder to push it through the blood vessels and ultimately raising blood pressure.
3: PKD Activates the Sympathetic Nervous System (SNS)
The Sympathetic Nervous System (SNS) is responsible for your body’s fight or flight response. The SNS creates the fight or flight response by releasing epinephrine, a powerful hormone. In high doses, it causes a surge in heart rate, blood pressure, and blood sugar.
In people with PKD, the SNS activates, regularly releasing small doses of epinephrine. This results in higher epinephrine levels, which correlates with higher blood pressure.
Of course, a person with PKD can also develop hypertension the same way anyone might. Smoking, obesity, not exercising, too much salt, and obstructive sleep apnea can all contribute to hypertension.
In the next chapter, I’ll explain how people with PKD can lower their blood pressure.
- ADPKD: Evaluation and Management of Hypertension. Arlene B Chapman, MD, Frederic F Rahbari-Oskoui, MD, MSCR, and William M Bennett, MD. 2021.
Disclaimer
When you start to take steps to lower your blood pressure, it’s important that you don’t do too much at once and cause hypotension, low blood pressure. Talk with your doctor before doing anything to lower your blood pressure, especially if you’re taking blood pressure medication.
The information provided in this post is designed to provide helpful information on the subjects discussed based on the author’s personal experience and research. This post is not meant to be used, nor should it be used, to diagnose or treat any medical condition. For diagnosis or treatment of any medical problem, consult your own doctor. The author is not responsible for any specific health or allergy needs that may require medical supervision and is not liable for any damages or negative consequences from any treatment, action, application, or preparation to any person reading or following the information in this post. References are provided for informational purposes only and do not constitute endorsement of any websites or other sources. Readers should be aware that the websites listed in this post may change.
