High Blood Pressure

What Causes High Blood Pressure?

In order to understand the causes of high blood pressure, you need to understand the causes of each type of high blood pressure separately.

There are two types of high blood pressure or hypertension:

Primary (Essential) Hypertension
Secondary Hypertension

Primary or Essential Hypertension
Essential hypertension is the condition when a specific cause for high blood pressure cannot be located. It is a common condition affecting almost 95 % of high blood pressure patients. Though the cause of primary hypertension is unknown, it is believed that several factors like genes, environment, and many more like these cause this type of hypertension. Approximately 75 million Americans suffer from primary hypertension.

Here are some basic causes of primary hypertension:

1) Family history: Primary hypertension can be genetic or hereditary. But researchers have not been able to recognize the genes responsible for hypertension yet.

2) Type 2 Diabetes: It is a well known fact that there is a strong association between diabetes and hypertension. Obesity, kidney damage, and insulin resistance are also believed to be the causes of essential hypertension.

3) Innate aberration in the sympathetic nervous system: The sympathetic nervous system controls the heart rate, blood pressure, and the diameter of the blood vessels. Any abnormality in this system may account for this type of hypertension.

4) Obesity: Obesity can lead to structural changes in the kidney and abnormal control of sodium. This can also lead to essential hypertension.

5) Low Levels of Nitric Oxide: Nitric oxide, a gas, influences the smooth muscle cells that line the blood vessels and help keep them flexible and prevent blood clotting. But when the level of nitric oxide goes down, it can cause essential hypertension.

Secondary Hypertension
Secondary hypertension is caused due to several medical conditions. One such condition is kidney diseases. Kidney diseases include:

1) Polycystic kidney disease: In this condition cysts form in the kidneys. These cysts often disrupt the normal functioning of the kidney and raise the blood pressure.

2) Glomerulonephritis: Glomerulonephritis is the inflammation of the kidney filter. Because of the inflammation, glomeruli are unable to function normally, which may lead to high blood pressure.

3) Hydronephrosis: At times, certain parts of your kidney get plugged. This condition is called Hydronephrosis. Hydronephrosis prevents the smooth flow of urine and subsequently raises the blood pressure.

4) Sleep apnea: In this medical condition breathing halts briefly but repeatedly during your sleep.

Apart from these, there are some other medical conditions also that cause temporary hypertension. These include pregnancy, cirrhosis, and Cushing's disease.