CRC - Nutrition, Lifestyle Factors, and Blood Pressure
|Publication Date:||25 June 2012|
Hypertension is a major risk factor for coronary heart disease, stroke, and premature death, and it affects approximately one-third of adults in the United States. Approximately, another one-third of the adults in the United States have prehypertension, which is also associated with a graded, increased risk of cardiovascular diseases and progression to hypertension. National surveys (NHANES 2007-2008) indicate that, despite steady progress, the awareness, detection, and treatment of hypertension remain unsatisfactory in the United States, that is, about 20% of all hypertensive individuals are unaware of their illness, 28% are not being treated, and only 69% of treated patients had controlled hypertension. The direct and indirect costs of hypertension in the United States were $63.5 billion in 2006, refl ecting a public health challenge and a continuing need for effective health policy and practice to prevent and manage hypertension. In the face of the aging population and the growing epidemic of obesity, the challenges related to hypertension continue to rise.
Even though enormous advancement has been made in identifying evidencebased lifestyle strategies for hypertension prevention and management, little progress has been made in implementing these proven strategies. Accumulating evidence supports that hypertension is preventable and that it is closely related to modifi - able factors such as dietary pattern and other lifestyle factors. The Joint National Committee (JNC) on Prevention, Detection, Evaluation and Treatment of High Blood Pressure was appointed by the National Heart, Lung, and Blood Institute to provide evidenced-based clinical guidelines for the prevention and management of hypertension. Current JNC guidelines (JNC7) recommend reduction in salt intake, moderate alcohol consumption, weight loss if overweight, aerobic exercise, increase in potassium intake, and following the DASH eating pattern to lower blood pressure (BP). JNC8 was in progress at the time this book was written, but it is unlikely to change these evidence-based recommendations. These lifestyle modifi cations are all recommended as part of the fi rst-line therapy for low-risk individuals defi ned as those without diabetes or cardiovascular diseases and with systolic blood pressure or diastolic blood pressure < 160/100 mmHg (i.e., stage 1 hypertension). These lifestyle modifi cations are also recommended for individuals with prehypertension to prevent the development of high BP and for use in combination with pharmacotherapy for hypertension more severe than stage 1.
Most of these lifestyle recommendations, however, have fared poorly in the United States. Adherence to these recommendations by both the clinicians and the public has been less than satisfactory. In most of the cases, clinicians do not even mention about lifestyle modifi cations to patients during their clinic visit, perhaps due to lack of training and limited resources. At the population level, the amount of salt intake continues to stay above the recommended levels, and the obesity epidemic remains worrisome; only less than 5% of the adults in the United States meet the recommended physical activity level; and fi nally, Americans continue to consume far less than the recommended amounts of fruits, vegetables, fi ber, calcium, magnesium, and potassium-all of which are key components of the DASH dietary pattern, which lowers BP.
Undoubtedly, implementing dietary and lifestyle modifi cations is challenging, and effective strategies for sustainable implementation are urgently needed. Thus, the main purpose of this book is to compile science-based practical information for health care providers to provide effective lifestyle interventions for controlling BP. The book is divided into four sections. Section I provides an overview of the scientifi c evidence relating nutrition and lifestyle to BP control and relevant considerations for real-life situations. Section II focuses on the different aspects of implementing the recommended lifestyle modifi cations. Section III discusses several special considerations in BP control and lifestyle modifi cations among children and adolescents, pregnant women, and those with diabetes. Section IV compiles simple practical tools that health care providers can put into practice in particular settings. At the end of each of the chapters, a summary table with existing key evidences and expert recommendations is also included.
We have collectively conducted many lifestyle intervention trials and observed the effect of nutrition and lifestyle interventions on BP and many other health indicators. It is our desire and sincere wish that this book may supplement the existing resources and shorten the gap between current understanding of the science about the relationship between lifestyle factors and BP and the actual implementation of the science. Ultimately, we hope that the trend in lifestyle interventions for hypertension prevention and treatment may be shifted. We sincerely appreciate all the authors for their contribution to this book. Without their help, this book would not have been completed.