Blood pressure, mmHg
NICE 2011 [3]
ESH/ESC 2013 [4]
AHA/ACC/CDC 2013 [6]
ASH/ISH 2013 [5]
JSH 2014 [7]
JNC 8 [2]
Definition of hypertension
≥140/90 and daytime ABPM (or home BP) ≥135/85
≥140/90
≥140/90
≥140/90
≥140/90 and home BP ≥135/85
Not addressed
In mild hypertension at low to moderate risk, lifestyle management without drugs can be considered
Not addressed
Not addressed
3 months
Some months
3 months
Not addressed
Initiate drug therapy in low-risk patients
≥160/100 or daytime ABPM ≥150/95
≥140/90
≥140/90
≥140/90
≥140/90
≥140/90 for <60 years
≥150/90 for ≥60 years
Blood pressure targets
Diabetes
Not addressed
<140/85
<140/90
Lower targets may be appropriate
<140/90
<130/80
<140/90
CKD with proteinuria
Not addressed
SBP <130 may be considered
<140/90
Lower targets may be appropriate
<130/80
<130/80
<140/90
Elderly
<150/90 for ≥80 years
SBP 140–150 for ≥80 years
<140/90
Lower targets may be appropriate
<150/90 for ≥80 years
<150/90 for >75 years,
<150/90 for ≥60 years
<140/90, if tolerated
For most adults, high BP, called essential hypertension or primary hypertension, tends to develop gradually with aging. The incidence of hypertension in the Framingham Heart Study showed that, for categories of participants <65 years and ≥65 years respectively, 5.3 % (95 % CI 4.4–6.3 %) and 16.0 % (12.0–20.9 %) of participants with optimal BP, 17.6 % (15.2–20.3 %) and 25.5 % (20.4–31.4 %) with normal, and 37.3 % (33.3–41.5 %) and 49.5 % (42.6–56.4 %) with high-normal BP progressed to hypertension within 4 years [8]. In a Japanese urban population, during 7 years of follow-up, there were 21, 63, and 137 cases of incident hypertension per 1,000 person-years in optimal, normal, and high-normal BP categories respectively. Compared with the optimal BP category, the adjusted hazard ratios (HRs; 95 % confidence intervals) for incident hypertension were 2.36 (2.07–2.70) and 5.11 (4.50–5.80) in the normal and high-normal BP categories, respectively [9]. Therefore, an annual medical examination is important for the prevention and early detection of hypertension.
Primary hypertension can be defined as elevated BP of unknown cause due to cardiovascular risk factors, resulting from environmental factors, including dietary factors and genetic factors, and interactions among these factors. Of the environmental factors that affect BP, diet plays a predominant role in BP homeostasis. Although the initiation of drug therapy in patients at a high level of risk should not be delayed, appropriate lifestyle modifications are recommended, not only to help treat hypertension, but also to prevent the development of hypertension and other CVD. Various hypertension guidelines represent the environmental risk factors of primary hypertension in slightly different terms. Each presents five to nine lifestyle modifications, based on the accumulated clinical and experimental evidence.
According to the 2013 European Society Hypertension and European Society of Cardiology Guideline for the management of arterial hypertension (ESH/ESC 2013) [4] the lifestyle section specifies:
1.
Salt restriction to 5–6 g per day
2.
Moderation of alcohol consumption to no more than 20–30 g and 10–20 g of ethanol per day in men and women respectively
3.
Other dietary changes, including increased consumption of vegetables, fruits, and low-fat dairy products
4.
Weight reduction to a BMI of 25 kg/m2 and waist circumference reduction to <102 cm in men and <88 cm in women, unless contraindicated
5.
Regular physical exercise, i.e., at least 30 min of moderate dynamic exercise 5–7 days per week
6.
Smoking cessation, i.e., giving all smokers advice on quitting smoking and offering assistance.
The Japanese Society of Hypertension Guideline 2014 (JSH2014) [7] emphasizes that lifestyle modifications are important for preventing hypertension, both before and after the start of antihypertensive drug therapy. The JSH2014 lists the following seven items subsequent to it:
1.
Salt reduction: the target of salt reduction <6 g/day
2.
Dietary pattern: increased fruits/vegetables and fish (fish oil) intake and reduced cholesterol/saturated fatty acid intake
3.
Weight control: the target body mass index (BMI) <25 kg/m2
4.
Exercise: primarily periodic (30 min or longer daily if possible) and aerobic exercise
5.
Reduction of alcohol intake
6.
Smoking cessation and avoidance of passive smoking
7.
Others: avoidance of exposure to cold and the management of emotional stress
In addition to these recommendations, it is noted that comprehensive lifestyle modifications are more effective.
The Clinical Management of Primary Hypertension in Adults is a report issued by the National Institute for Health and Care Excellence (NICE) in 2011 [3]. This UK guideline suggests the following lifestyle interventions on the part of physicians:
1.
Offer lifestyle advice both initially and then periodically to people undergoing assessment or treatment for hypertension
2.
Ascertain patients’ diet and exercise patterns as a healthy diet and regular exercise can reduce BP. Provide appropriate guidance and written or audiovisual materials to promote lifestyle changes
3.
Relaxation therapies can reduce BP and people may wish to use these as part of their treatment. However, routine provision by the primary care team is not currently recommended.
4.
Ascertain patients’ alcohol consumption and encourage reduced intake if patients drink excessively, because this can reduce BP and has broader health benefits
5.
Discourage excessive consumption of coffee and other caffeine-rich products
6.
Encourage patients to keep their dietary sodium intake low, either by reducing or substituting sodium salt, as this can reduce BP
7.
Do not offer calcium, magnesium, or potassium supplements as a method of reducing BP
8.
Offer advice and help to smokers on smoking cessation
9.
Studies have found that group work is effective at motivating lifestyle changes. Inform people about local initiatives by, for example, healthcare teams of patient organizations that provide support and promote healthy lifestyle change
The 2014 Canadian Hypertension Education Program Recommendations for BP Measurement, Diagnosis, Assessment of Risk, Prevention, and Treatment of Hypertension (CHEP 2014) also provides the Prevention and Treatment Recommendations. In this section, there is a subsection on health behavior management, where they recommended the following measures:
1.
Physical activity: prescribe the accumulation of 30–60 min of moderate-intensity dynamic exercise (e.g., walking, jogging, cycling, or swimming) 4–7 days per week in addition to the routine activities of daily living, and emphasize the ineffectiveness of higher-intensity exercise
2.
Weight reduction: maintenance of a healthy body weight (body mass index of 18.5–24.9, and waist circumference <102 cm for men and <88 cm for women) for nonhypertensive individuals to prevent hypertension and for hypertensive patients to reduce BP, encourage all overweight hypertensive individuals to lose weight, and use a multidisciplinary weight-loss strategy including dietary education, increased physical activity, and behavioral intervention.
3.
Alcohol consumption: limit to two drinks per day, and consumption not exceeding 14 standard drinks per week for men and nine standard drinks per week for women (note: one standard drink is considered to be equivalent to 13.6 g or 17.2 mL of ethanol or approximately 44 mL [1.5 oz] of 80 proof [40 %] spirits, 355 mL [12 oz] of 5 % beer, or 148 mL [5 oz] of 12 % wine)
4.
Dietary recommendation: eating more fruits, vegetables, low-fat dairy products, dietary and soluble fiber, whole grains, and protein from plant sources that have low saturated fat and cholesterol content (Dietary Approaches to Stop Hypertension [DASH])
5.
Sodium intake: reducing toward 2,000 mg (5 g of salt or 87 mmol of sodium) per day
6.
Potassium, calcium, and magnesium intake: nonrecommendation of supplementation
7.
Stress management: more likely to be effective for individualized cognitive-behavioral interventions when relaxation techniques are used.
An Effective Approach to High Blood Pressure Control has been reported by a Science Advisory from the American Heart Association, the American College of Cardiology, and the Centers for Disease Control and Prevention [6]. This report recommends lifestyle changes for all hypertension patients as follows:
1.
DASH diet [10]: consume a diet rich in fruits, vegetables, and low-fat dairy products with a reduced content of saturated and total fat
2.
Sodium restriction (≤2.4 g/day)
3.
Weight reduction: if BMI ≥25 kg/m2
4.
Exercise: at a moderate pace to achieve 150 min/week (i.e., 30 min/5 days/week)
5.
Limit daily alcohol: no more than one drink (women) or two drinks (men)
6.
Smoking cessation: counseling tobacco users on the health risks of smoking and the benefits of quitting strongly recommended.
These representative lifestyle improvement guidelines for hypertension can be summarized in the six following bullet points:
Healthy diet (DASH diet, consume a diet rich in fruits, vegetables, and low-fat food or fish with a reduced content of saturated and total fat)
Sodium restriction
Weight reduction
Regular exercise
Moderate alcohol consumption
Smoking cessation
The lifestyle modifications are present in all the guidelines regardless of the specific frame [11]. In addition, the health behavior recommendations that appear in the guidelines for the management of hypertension are very similar to the recommendations appearing in the Guidelines for the Primary Prevention of Stroke: A Statement for Healthcare Professionals From the American Heart Association/American Stroke Association [12] and the European Stroke Organization (ESO) guidelines [13] for the primary prevention of stroke incidence.
Mechanisms of salt intake and elevated BP are an increase in extracellular volume and hence, in peripheral vascular resistance [14]. High salt intake has the ability to chronically increase renal sympathetic nerve activity and contribute to elevating BP [15]. The WHO Guidelines strongly recommend a salt intake of <5 g/day [16]. High salt intake and a high rate of salt sensitivity among the Japanese may contribute to their elevated BP [17]. The Japanese Guideline sets a target of restricting salt intake to <6 g/day, taking into consideration the current circumstances in Japan.
Vegetable and fruits are abundant in dietary fiber, potassium, magnesium, and antioxidant vitamins, the intake of which is inversely associated with BP [18–22]. High intake of fruits and vegetables reduces the risk of developing hypertension. The ESH/ESC 2103 recommends that patients with hypertension should be advised to eat 300–400 g/day of fruits and vegetables. The JSH2014 focuses on vegetables, recommending that patients with hypertension eat at least 350 g/day of vegetables.
Dietary n-3 polyunsaturated fatty acids (PUFAs) and fish oil have been shown to have a weak but significantly inverse association with BP [23, 24]. Even a small fish intake (30–60 g/day) was shown to reduce the risk of coronary heart disease and sudden cardiac death in Western countries (Chap. 27) [25]. The WHO CARDIAC (Cardiovascular Diseases and Alimentary Comparison) Study showed that the Japanese have one of the highest n-3 PUFA intakes and one of the lowest number of coronary heart disease mortalities worldwide [26]. The ESH/ESC 2013 guideline recommends that hypertensive patients eat fish at least twice a week.
Obesity and overweight are established risk factors for CVD, hypertension, dyslipidemia, diabetes mellitus, and metabolic syndrome [27]. A meta-analysis of studies estimated that each kilogram of weight loss reduced BP by 1.05 mmHg systolic and 0.92 mmHg diastolic [28].
Many prospective cohort studies have demonstrated that physical inactivity is associated with an increasing risk of hypertension [29, 30]. In a meta-analysis, eight randomized controlled trials showed that pedometer users significantly increased their physical activity, completing 2,491 more steps/day than controls [31]. Participants in this intervention decreased their systolic blood pressure (SBP) significantly by 3.8 mmHg.
Regular alcohol consumption can lead to an increase in BP [32]. A meta-analysis also showed the hypotensive effects of alcohol restriction [32]. In heavy drinkers, BP is increased after an abrupt reduction of drinking, but it can be subsequently reduced if the restriction is continued. In the ESH/ESC 2013, moderate daily alcohol consumption translates to no more than two drinks in men or one drink in women. In the JSH2014, drinking, in terms of ethanol intake, should be restricted to 20–30 mL (equivalent to 180 mL of sake (a Japanese alcoholic beverage), 500 mL of beer, 90 mL of shochu [distilled spirits], a double whisky or brandy, and two glasses of wine)/day or less in men and to 10–20 mL per day or less in women.
Cigarette smoking causes an acute pressor effect that may elevate BP [33]. It is reported that, in passive smokers, 24-h BP is high, and the incidence of masked hypertension is also high [34].
30.2.2 Secondary Hypertension
Some people have high BP caused by an underlying condition. This type of high BP is called secondary hypertension. Secondary hypertension tends to appear suddenly and to cause higher BP than primary hypertension. Various conditions and medications can lead to secondary hypertension, including:
1.
Diseases such as adrenal gland tumors, thyroid problems, renovascular disease, kidney problems, and obstructive sleep apnea
2.
Intoxication as found in acute alcohol abuse or chronic alcohol use, and in illegal drug use, such as cocaine and amphetamines
3.
Iatrogenic routes caused by certain medications, such as birth control pills, decongestants, over-the-counter pain relievers, cold remedies, and some prescription drugs
4.
Congenital anomalies leading to defects in blood vessels
30.3 Complications
30.3.1 High BP and Atherosclerosis
Elevated systolic BP is an important risk factor for carotid atherosclerosis [35]. There is an additive relationship between oral health disorders (severe periodontitis, gingival bleeding, lowest quartile of tooth number, and malocclusion) and risk of hypertension [36, 37]. A possible pathogenetic background of an association between periodontitis and BP would be oral inflammation, the role of the host immune response, the direct microbial effect on the vascular system and alterations in endothelial function (Chap. 26) [38].
30.3.2 Cardiovascular Disease and Hypertension
Hypertension is the most significant risk factor for incident stroke worldwide [39, 40]. The total population-attributable fractions of higher BP for CVD are approximately 30–50 % [41].
A review of major prospective cohort studies and an updated meta-analysis of >40 randomized controlled trials of BP lowering (including >188,000 participants and approximately 6,800 stroke events) showed that in the Asian Pacific region in addition to North America and Western Europe, each 10 mmHg reduction in systolic BP is associated with a decrease in risk of approximately one-third in subjects aged 60–79 years [42]. In a meta-analysis of randomized controlled studies of subjects aged over 65 years, reducing BP to a level of 150/80 mmHg is associated with large benefit in stroke, CVD, and all-cause mortality [43]. SBP rather than diastolic blood pressure (DBP) reduction is significantly related to lower cardiovascular risk.
A meta-analysis of self-measurement of home BP has shown 1.24- and 1.20-times increased risks of a cardiovascular event and 1.33- and 1.30-times increased risks of incident stroke for high-normal conventional BP and mild hypertension respectively [44]. Among people with optimal, normal, and high-normal conventional BP, 5.0, 18.4, and 30.3 % respectively had masked hypertension (home BP ≥130 mmHg systolic or ≥85 mmHg diastolic). Compared with true optimal conventional BP, masked hypertension was associated with a 2.3-times increased risk of CVD [44].
30.3.3 Kidney Disease and Hypertension
Hypertension is a major cause of kidney disease and kidney failure [45]. In the Suita Study, the risk of CVD was higher in chronic kidney disease (CKD) patients with normal and high-normal BP than in non-CKD individuals in the same BP categories [46]. To prevent CVD, control of both BP and renal function is important, because of the mutual exacerbation of decreased kidney function and hypertension [47].
30.3.4 High BP and Diabetes Mellitus
Hypertension is a risk factor for the development and worsening of many complications in patients with diabetes mellitus. In an urban Japanese population cohort study, the subjects with high-normal blood pressure in any glucose category and the normal BP subjects with impaired fasting glucose levels showed increased risks of CVD [48]. These two groups of borderline disease subjects, i.e., subjects with prehypertension (normal and high-normal BP) and impaired fasting glucose comprised approximately 10 % of all population-wide subjects (30 or more years of age), and had a two-fold increased risk of a CVD event compared with the subjects with optimal BP and normoglycemia. Subjects with either borderline condition should be targeted for health guidance.
30.3.5 Metabolic Syndrome and High BP
Metabolic syndrome is a group of health problems that consists of abdominal obesity, elevated BP, hyperglycemia, hypertriglyceridemia, and hypo-HDL cholesterolemia. In a meta-analysis study that identified 87 studies and included 951,083 subjects, metabolic syndrome is associated with a two-fold increased risk of cardiovascular outcomes and a 1.5-fold increased risk of all-cause mortality [49].
30.3.6 Preeclampsia: High BP and Pregnancy
A meta-analysis of studies of pregnant women with chronic hypertension has recently shown that women with chronic hypertension had high pooled incidences of superimposed preeclampsia (25.9 %, 95 % confidence interval 21.0–31.5 %) (Chaps. 60 and 61) [50].
30.3.7 High BP and Erectile Dysfunction
A high incidence of erectile dysfunction was found in hypertensive patients from Spanish specialized care hypertension units. Sildenafil improved the score in the erectile function domain [51].
30.3.8 High BP and Eye Disease
In a meta-analysis of individual participant data, retinal arteriolar narrowing (per 20-μm difference) and venular widening (per 20-μm difference) were associated with 1.29- and 1.14-fold increased risks of hypertension respectively. These findings demonstrate the importance of microvascular remodeling in the pathogenesis of hypertension.
30.3.9 Hypertension and Dementia
A meta-analysis of six longitudinal studies showed that hypertension is associated with a 1.59-fold increased risk of incident vascular dementia [52]. The Hisayama study showed that mid-life and late-life hypertension are significant risk factors for late-life vascular dementia, but not for Alzheimer’s disease [53]. Mid-life hypertension is associated with vascular dementia, regardless of late-life BP levels.
30.4 Principles of Treatment
The objective of treating hypertension is to prevent cardiovascular and renal diseases; thus, the goal of treatment for hypertension is not only to manage BP, but also to deal with the risk factors that hypertension and CVD share, including lipid disorders, glucose intolerance or diabetes, obesity, and smoking.
< div class='tao-gold-member'>
Only gold members can continue reading. Log In or Register to continue
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
