Does Neurofibromatosis (NF1) Cause High Blood Pressure?

Yes, as an adult with NF1, you do need to monitor your blood pressure closely. High blood pressure (hypertension) is more common in individuals with neurofibromatosis type 1 than in the general population ^[1]. While many adults with NF1 develop standard “essential” hypertension—the same kind that affects millions of people without the condition—the genetic changes in NF1 also increase your risk for specific, hidden causes of high blood pressure. Because these underlying causes require specialized treatment, doctors recommend that every adult with NF1 have their blood pressure checked at least once a year for life ^[1].

Essential Hypertension vs. Secondary Hypertension

When high blood pressure has no identifiable medical cause other than genetics, age, and lifestyle factors, it is called essential hypertension. This is very common. However, if your high blood pressure is caused by a specific underlying medical condition, it is called secondary hypertension.

If you develop high blood pressure, especially if you are young or if standard blood pressure medications do not seem to work (often called refractory hypertension), your doctor should investigate whether an NF1-related complication is the root cause ^[2][3]. This investigation may involve specialists like cardiologists, nephrologists (kidney doctors), or endocrinologists (hormone doctors). Two of the most important NF1-related causes of secondary hypertension are renal artery stenosis and pheochromocytomas.

Renal Artery Stenosis (RAS)

NF1 can affect how blood vessels grow and function, a condition known as vasculopathy ^[4]. This can cause arteries to become thickened, fragile, or narrowed ^[4]. When this narrowing happens in the arteries that supply blood to your kidneys, it is called renal artery stenosis ^[5]. While it can happen at any age, it is a particularly common cause of high blood pressure in children and young adults with NF1.

Because your kidneys play a major role in regulating blood pressure, restricted blood flow makes them think your body’s overall blood pressure is too low. In response, they release hormones that drive your blood pressure dangerously high ^[5]. If you are diagnosed with renal artery stenosis, medication may be the first step. However, sometimes a procedure to open the narrowed artery (angioplasty) is necessary to get your blood pressure back under control ^[6][7].

Pheochromocytoma

A pheochromocytoma is a rare, usually non-cancerous tumor that grows in the adrenal glands (small glands sitting on top of the kidneys) ^[8]. While rare in the general public, individuals with NF1 have a higher risk of developing them, most commonly in adulthood ^[9][10].

These tumors act like factories that pump out excess stress hormones (like adrenaline), causing erratic and sometimes extreme spikes in blood pressure ^[8]. Symptoms can include sudden pounding headaches, sweating, and a racing heart (palpitations) ^[2].

It is crucial to know if you have a pheochromocytoma because the sudden release of hormones can cause severe, potentially life-threatening blood pressure emergencies—especially when the body is under physical stress ^[11][12]. Fortunately, these risks are highly manageable and preventable as long as the tumors are identified ahead of time.

If your blood pressure is normal and you have no symptoms, current guidelines do not recommend routine hormone testing for pheochromocytomas just because you have NF1 ^[13]. However, screening is incredibly important—and serves as a critical exception to that rule—in specific situations:

• Before surgery: Undiagnosed pheochromocytomas can cause dangerous blood pressure volatility during general anesthesia. Screening prior to surgery is crucial because many of these tumors can be “silent” or asymptomatic ^[14][12].
• During pregnancy: The physical stress of pregnancy and childbirth with an undiagnosed pheochromocytoma poses severe risks to both the mother and baby, so screening before or during pregnancy should be discussed with your doctor ^[15][10].

Screening for a pheochromocytoma is straightforward and non-invasive. It typically involves a simple blood draw or a 24-hour urine collection to check your body’s levels of stress hormone breakdown products (metanephrines) ^[16].

What You Can Do

• Annual Screening: Have your blood pressure checked by a healthcare provider at least once a year ^[1].
• Pre-Surgical and Pregnancy Checks: If you are planning to have surgery or become pregnant, explicitly remind your care team that you have NF1 and ask to be screened for a pheochromocytoma ^[14][10].
• Track Your Numbers: Keep a log of your blood pressure readings, especially if you have been feeling off, having sudden headaches, or experiencing a racing heartbeat.
  • How to measure: Sit quietly for 5 minutes, keep your arm supported at heart level, and avoid caffeine or exercise beforehand to ensure accurate readings.
  • When to call: While you should ask your doctor for personalized targets, generally, if your readings are consistently above 130/80 mmHg, or if you experience sudden, large spikes, you should contact your healthcare provider.