There are two types of hypertension, called “primary” and “secondary.” Primary hypertension means that the hypertension is not caused by any other disease or condition and it gradually develops over time with age. Secondary hypertension means that the hypertension is caused by another disease or conditions. Secondary hypertension tend to result in higher blood pressure than primary hypertension. In most cases (90-95%), hypertension is primary. Only a small amount of hypertension (5-10%) is secondary.