Hypertension can be classified as either essential hypertension or secondary hypertension. Essential hypertension does not have a known cause and can be linked to a plethora of pathophysiologic factors. Factors associated with essential hypertension include: increased SNS activity, long term high sodium intake, diabetes mellitus, and obesity.Secondary hypertension is often the result of a separate pathophysiological condition such as: renal disease, primary aldosteronism, and obstructive sleep apnea.