Heart, Stroke | January 5, 2016 | Author: The Super Pharmacist
Brief: Prehypertension: Adults between 18 and 30 with blood pressure above 120/80 but below 139/89 are deemed to be prehypertensive. What implication does this have for the person’s long term cardiovascular health. What is an appropriate course of action for this person in terms of reducing future potential cardiovascular complications?
Pre-hypertension is a medical classification for individuals who have a blood pressure elevated above normal levels but not to the level classified as hypertension (high blood pressure). According to ICD-9 classification, blood pressure readings for pre-hypertension are classified as a systolic pressure from 120 to 139 mmHg or a diastolic pressure from 80 to 89 mmHg (readings greater than or equal to 140/90 mmHg are classified as hypertension) (1). It is estimated that nearly half of all adults over 18 are pre-hypertensive or have already developed hypertension, and there are a wide range of studies highlighting the increased risk of cardiovascular events. The renowned Framingham Heart Study demonstrated a 2.5 fold increased risk of cardiovascular events in women 10 years after being diagnosed, and a 1.6 increase for men with blood pressures between 130-139/85-89mmHg (2). A comprehensive meta-analysis of 18 studies including almost half a million patients also found that pre-hypertensive patients had a 55% increased risk of cardiovascular disease and a 71% increased stroke risk (3). Pre-hypertension itself is asymptomatic and is largely used as an indicator for lifestyle change to prevent the development of hypertension and associated complications further down the line.
Overweight or obese individuals are at significantly heightened risk of pre-hypertension. It is also much more common in younger people, although this is often as a result of many older people having developed hypertension after being pre-hypertensive earlier in life. It is more common in men than women, and race is a significant risk factor – it is much more prevalent in individuals who have Black or South Asian heritage. A family history of high blood pressure is also often a good indicator of pre-hypertension, as is the use of tobacco, diets that are high in salt, or certain chronic conditions such as sleep apnoea, kidney disease and diabetes. The prevalence of pre-hypertension is set to increase dramatically across the world in line with growing obesity rates and poor lifestyle habits.
Pre-hypertension is considered in many sections of the medical community to be a risk factor for future high blood pressure and subsequent increased risk of heart attacks, coronary heart disease, heart failure, kidney failure and stroke (4). Starting with a blood pressure as low as 115/75 mmHg, heart attack and stroke doubles for each 20 point rise in systolic blood pressure or 10 point rise in diastolic blood pressure for adults aged between 40-70 (5). Research has also demonstrated that patients who have been diagnosed as pre-hypertensive have a much greater risk for other cardiovascular risk factors including high cholesterol, obesity and diabetes (6). These risk factors are more prevalent in the pre-hypertensive population than those who have normal blood pressure. Aside from cardiovascular health, there are a small number of studies investigating the relationship between pre-hypertension and later life organ failure. A 2006 study, published in the Journal of hypertension, demonstrated that pre-hypertensive patients demonstrated much earlier signs and greater incidence of kidney dysfunction as compared to patients with optimal blood pressure (7).
Pre-hypertension serves as a warning sign that an aspect of an individual’s lifestyle may require changing in order to reduce the risk of any future cardiovascular event. All of these changes are non-medical in nature, with the most effective method of reducing cardiovascular being to lose weight. Individuals who are pre-hypertensive and overweight have much to gain through modifying their diet and leading a more active lifestyle, with studies evidencing that even modest weight loss can reduce the risk of progression to hypertension by approximately 20% (8). Diets that are rich in fruits, vegetables, whole grains, fish and low fat diary can help either lower or prevent high blood pressure. Diets that contain all these foods, and are also low in sodium and high in potassium, calcium, fibre, magnesium and protein are often referred to collectively as Dietary Approaches to Stop Hypertension (DASH). Salt (sodium) is a significant contributor to high blood pressure and, where possible, should be limited to one teaspoon per day. Diets that are high in saturated and trans-fats – including large amounts of meat and high-fat dairy, margarine, snack foods and pastries – can also contribute to high blood pressure and obesity. Similarly, food that is rich in cholesterol such as high-fat diary, egg yolks and organ meats should only be eaten in moderation to prevent further risk of hypertension. Limiting the amount of alcohol consumed, and stopping smoking, also helps bring down blood pressure significantly.