Risk Factors for High Blood Pressure

High blood pressure rarely has a single cause. In about 9 out of 10 people it develops from a mix of genes, age and lifestyle; this is called primary (essential) hypertension. In the rest, a specific medical condition or medication is responsible. Knowing your risk factors helps you see which ones you can change.

Two lists of high blood pressure risk factors: five that cannot be changed and eight that can, such as weight, salt and smoking — Some risk factors are fixed, but many can be changed — and improving several at once adds up.

Risk factors you cannot change

Age: arteries stiffen over the years, and systolic pressure rises. Most people over 65 have high blood pressure. See age and blood pressure.
Family history: if one or both parents have hypertension, your risk is higher. Genes play a role, though shared eating habits matter too.
Ethnic background: people of African descent tend to develop high blood pressure earlier and more severely, and people of South Asian descent also have a higher risk.
Sex: men develop hypertension earlier; in women, blood pressure rises faster after menopause.
Pregnancy history: women who had high blood pressure or preeclampsia during pregnancy have a higher risk later in life.

Risk factors you can change

Factor	Why it matters
Excess weight, especially around the waist	Raises blood volume, hormone activity and nerve signals that increase pressure; about 1 mmHg drop per kg lost
High salt intake	Sodium makes the body retain water. See salt
Few vegetables and fruit	Low potassium intake raises blood pressure
Physical inactivity	Regular exercise lowers blood pressure by 5–8 mmHg. See exercise
Alcohol	Raises blood pressure in a dose-dependent way. See alcohol
Smoking	Raises blood pressure after each cigarette and damages arteries. See smoking
Poor sleep and chronic stress	Keep stress hormones and the nervous system activated
Type 2 diabetes and insulin resistance	Often occur together with hypertension and add to the damage

These factors add up. Improving several of them at once can lower blood pressure substantially. See 5 Quick and Easy Ways to Lower Your Blood Pressure.

Secondary causes

In about 5–10% of people with hypertension, a specific cause is found. Treating it can improve blood pressure markedly, sometimes cure it.

Obstructive sleep apnea: repeated breathing pauses at night. Clues are loud snoring, gasping in sleep and daytime sleepiness.
Chronic kidney disease: both a cause and a consequence of high blood pressure.
Primary aldosteronism: the adrenal glands produce too much of the hormone aldosterone, which retains sodium. It is more common than once thought, especially in people with hard-to-treat hypertension or low potassium.
Narrowing of the kidney arteries (renal artery stenosis).
Other hormone disorders: thyroid disease, Cushing's syndrome and, rarely, pheochromocytoma (a tumor that releases adrenaline).
Narrowing of the aorta (coarctation), a cause in children and young adults.

Medicines and substances that raise blood pressure

NSAID painkillers such as ibuprofen, naproxen and diclofenac
Decongestants in cold and flu medicines (pseudoephedrine, phenylephrine)
Combined oral contraceptives containing estrogen
Corticosteroids such as prednisone
Some antidepressants (for example venlafaxine) and stimulant medicines for ADHD
Some immunosuppressants and certain cancer drugs
Licorice in large amounts, cocaine and amphetamines

Do not stop a prescribed medicine on your own; ask your doctor or pharmacist whether an alternative is possible.

When to suspect a secondary cause

high blood pressure before age 40, or in a child
sudden onset or a sudden worsening of previously stable blood pressure
very high readings, or hypertension that stays high despite three medicines
low potassium in a blood test
symptoms such as episodes of palpitations, sweating and headache, or loud snoring

What to do

If you have several risk factors, check your blood pressure at least once a year and learn to measure it correctly at home. High blood pressure usually causes no symptoms; see warning signs of hypertension.

General information, not medical advice. Talk to your doctor before changing your diet, exercise or medication. A reading of 180/110 or higher with chest pain, shortness of breath, back pain, numbness or weakness, vision or speech problems, confusion or a severe headache is an emergency: call 911 (US) or your local emergency number.