Prehypertension

The pathogenesis of hypertension is multifactorial and highly complex. There are several influential factors that control blood pressure (BP) for adequate tissue perfusion, such as vascular reactivity, circulating blood volume, blood viscosity, cardiac output, blood vessel elasticity, and neural stimulation. Increased peripheral resistance, vascular rigidity, and vascular responsiveness to stimuli are significant to the pathophysiology of hypertension. Sodium has a primary effect on blood pressure leading to excess circulating volume, affecting hypertrophy, contractility, and vascular resistance (Buttaro, Trybulski, Bailey, Sandberg-Cook, 2011).

Prehypertension is blood pressure measurements with a systolic pressure from 120-139 mm Hg or a diastolic pressure 80-89 mm Hg. Prehypertension is typically asymptomatic and easily overlooked by clinicians. The progression of prehypertension to hypertension can be rapid, especially in individuals whose blood pressure lies in the higher ranges of

prehypertension. Prehypertension is routinely linked to obesity, metabolic syndrome, diets high in fat, excessive sodium intake, chronic stress, physical inactivity, and dyslipidemia. The possibility of chronic kidney disease (CKD) and cardiovascular (CV) event are higher in prehypertensive than hypertensive persons (Assadi, 2014).
African Americans have greater incidents of hypertension when compared to non-Hispanic whites or Mexican Americans. As a result, African Americans have higher occurrences of cardiovascular, stroke, renal complications, and higher mortality rates due to hypertension when compared to other ethnicities. An enhanced renal sodium reabsorption has been displayed in African Americans leading to hypertension among African Americans. Reducing sodium intake will lead to an overall decline in renal sodium reabsorption resulting in a decrease in blood pressure (Hernandez & Anderson, 2012).
The national high BP education program strongly suggests the implementation of healthy lifestyles to reach BP targets in prehypertensive individuals without diabetes or chronic renal disease. Methods for reducing high blood pressure include weight reduction, sodium restriction, alcohol intake moderation, exercise, and smoking cessation (Buttaro et al., 2011).
An established exercise routine and reduction of stress has shown to be beneficial as an aid in lowering blood pressure. Regular isometric exercise has been associated with counteracting the development of hypertension and reduces the incidence of cardiovascular events. Chronic stress may be an environmental factor that leads to the development of hypertension. An increased heart rate can be caused by stimulation of the sympathetic nervous system in response to physical or psychological stressors such as fever, anger, or anxiety. This response leads to constriction of the blood vessels leading to a rise in blood pressure. The temporary increase in blood pressure that follows is a normal response and is usually self-limited because the heart rate response is caused by catecholamines or reduced by the parasympathetic response (Buttaro et al., 2011).
The Dietary Approaches to Stop Hypertension (DASH) study displayed an association between a low potassium and increased sodium diet and hypertension.

This association results in increased sodium reabsorption, enhanced sympathetic nervous system stimulation, and increased angiotensin II and aldosterone production, all of which result in higher blood pressure. DASH, a diet consisting of substantial servings of fruits, vegetables, whole grains, low-fat dairy products, low in red meats, reduced sodium, decrease in saturated and total fat, low in sugar-containing drinks, and an increase in potassium has shown to significantly reduce blood pressure. Studies have shown a correlation between obesity, insulin resistance, and hypertension. A decrease in caloric intake by 500 kcal/day may result in an achievement of a weight reduction of 0.45 kg (1 pound) per week. A weight reduction of 4.5-kg (10-pound) has displayed a great decline in blood pressure (Hernandez & Anderson,

2012).
Nonpharmacologic treatment is an essential intervention for the treatment of prehypertension. Lifestyle modifications form the foundation of nonpharmacologic treatment. The decision to initiate antihypertensive drug treatment in individuals who are prehypertensive in the absence of diabetes or chronic renal disease should be formed on overall CV risk rather than on specific measurements of BP alone (Assadi, 2014). There are multiple factors such as caffeine, anxiety, and nicotine that may momentarily increase blood pressure value; therefore, a diagnosis of hypertension is based on BP measurements obtained during at least three office visits. In the suspicion of hypertension, routine laboratory tests should include urinalysis and complete blood count (CBC) with differential, serum electrolytes, blood urea nitrogen (BUN), serum creatinine, fasting blood glucose, fasting lipid profile, and serum uric acid (Hernandez & Anderson, 2013).