Causes of High Blood Pressure

High blood pressure is generally divided into two categories based on whether an underlying cause can be identified.

Primary (Essential) Hypertension

The large majority of high blood pressure cases have no single identifiable cause. Instead, it develops gradually from a combination of genetics, age, and lifestyle factors — including high salt intake, excess weight, physical inactivity, and chronic stress. This is the most common type by far.

Secondary Hypertension

A smaller percentage of cases result from an identifiable underlying condition, including kidney disease, certain hormonal disorders (such as thyroid problems or adrenal gland conditions), obstructive sleep apnea, and certain medications (including some decongestants, NSAIDs, and hormonal contraceptives). Secondary hypertension is worth considering when blood pressure is very high, develops suddenly, starts at a young age, or doesn't respond well to typical treatment.

Non-Modifiable Risk Factors

Age, family history, and certain genetic factors all increase risk and can't be changed — which is part of why some people develop high blood pressure despite a generally healthy lifestyle. Race and ethnicity also play a documented role: AHA and CDC data show meaningfully higher hypertension prevalence among Black adults, for example, independent of lifestyle factors. Race and ethnicity also play a documented role: AHA and CDC data show meaningfully higher hypertension prevalence among Black adults, for example, independent of lifestyle factors. Race and ethnicity also play a documented role: AHA and CDC data show meaningfully higher hypertension prevalence among Black adults, for example, independent of lifestyle factors.