The relationship between NF1 and blood pressure

Neurofibromatosis type 1 (NF1) is a genetic disorder that causes changes in skin pigmentation and tumors called neurofibromas, which grow along nerve fibers. Changes in skin pigmentation include flat, tan-to-brown patches of skin (called café-au-lait spots), nodules under the skin, and freckling in the armpits or groin. Neurofibromas are usually non-cancerous, but not always.

NF1 is caused by mutations to the NF1 gene, a tumor suppressor gene, meaning it contains instructions for making proteins that help regulate the growth and division of cells. More specifically, the NF1 gene contains instructions for making neurofibromin, a protein that performs several important regulating functions at the cellular level. When a person has NF1, neurofibromin does not function normally.

Symptoms and the severity of symptoms vary from person to person. Some people have only mild changes in skin pigmentation, while others develop large tumors that involve multiple nerves, called plexiform neurofibromas.

NF1 can also affect growth and bone development, causing curvature of the spine, larger than average head size, and short adult stature. Other symptoms and complications can include learning difficulties and tumors on the optic nerve.

Symptoms of NF1 typically begin in childhood but are mistaken for freckling or benign skin symptoms. As a person ages, additional symptoms appear. Diagnosis often takes several years, and many people with NF1 are not diagnosed until they are adults.

What is the treatment for NF1?

Treatment plans vary from person to person, depending on symptoms and the size and locations of neurofibromas. Treatment includes therapies that target tumors, such as surgery, chemotherapy, and medications that slow tumor growth.

Treatment also includes supportive therapies. For example, some people may benefit from medications to help with attention. Some may require surgery or orthopedic braces to help treat curvature of the spine or other bone growth abnormalities caused by NF1.

Because NF1 can cause different symptoms over time, regular checkups and monitoring are critical aspects of treatment.

One specific metric that people with NF1 and their healthcare providers should be checking regularly is blood pressure. This applies to people of all ages who are living with NF1.

What is blood pressure?

Blood pressure is the force that blood exerts on the walls of the blood vessels as it moves throughout the body. Blood pressure that is too high (hypertension) can damage blood vessels, contributing to atherosclerosis, or a buildup of arterial plaque that causes blood vessels to become stiff and narrowed. Hypertension can lead to heart failure, stroke, and kidney damage.

How can NF1 affect blood pressure?

The exact mechanisms of how NF1 affects blood pressure are not fully understood, but there are several factors that may contribute.

Mentioned above, neurofibromin regulates numerous important functions in the body. This includes functions related to the inner lining of blood vessels, smooth muscle cells (which control the relaxation and constriction of blood vessels), and the production and function of blood cells, including white blood cells. Some research suggests that dysfunctional neurofibromin may contribute to thickening of blood vessel walls, inflammation in blood vessels, and constricted blood vessels. These changes can affect blood vessels that supply the kidneys, brain, heart, and other organs.

NF1 may also cause or contribute to hypertension in other ways, including tumors on nerves that regulate blood pressure, tumors on glands that produce hormones that regulate blood pressure, and damage to the kidneys.

However, this is a simplified explanation of complex interactions between different cells and systems in the body. Again, the mechanisms are not fully understood.

It’s also important to mention that people with NF1 have the same health risks as people without NF1. Hypertension is extremely common, and it can have numerous causes and contributing factors.

What happens if you have NF1 and hypertension?

Treatment begins with a careful evaluation to identify what is contributing to hypertension. Once the causes are identified, a healthcare team will determine the best approach to treatment, which may include medications to lower blood pressure, procedures to widen constricted blood vessels, or treatments to target specific tumors that are affecting nerves or glands.

Your healthcare team will always be your best source of information.