Book Review

Obesity: Impact on cardiovascular disease

N Engl J Med 2000; 342:746-747March 9, 2000

Article

Obesity: Impact on cardiovascular disease
(American Heart Association Monograph Series.) Edited by Gerald F. Fletcher, Scott M. Grundy, and Laura L. Hayman. 377 pp., illustrated. Armonk, N.Y., Futura, 1999. $69. ISBN: 0-87993-418-2

Obesity is now a pandemic in industrialized societies. Who can feel confident that health care professionals have adequately met the needs of patients or communities with regard to this problem? By what measure do we know what these needs are? Obese patients may tell us first about their cosmetic concerns, their shortness of breath, or their sore knees. We, in turn, may tell them about their increased risk for diabetes or myocardial infarction. We are increasingly successful at tinkering with their blood pressure, blood lipids, and blood glucose levels. But the proportion of persons in our society who are overweight in relation to their height continues to creep (or leap) upward.

To help clarify our goals, it might be useful to answer the question of whether obesity has an effect on cardiovascular disease that is independent of the recognized cardiovascular risk factors. In chapter 1 of this monograph from the American Heart Association, the answer is yes, and in chapters 5 and 11, the answer is no. In the remaining 18 chapters, the authors skirt the question altogether. However, these disagreements and evasions need not be a problem for open-minded readers who want to learn something new about the complicated and important subject of obesity. Each chapter of the book provides readers with a different window on the topic.

Herein lies the appeal of this book. It contains 21 primers on how researchers and practitioners currently understand obesity from disparate perspectives, such as those of epidemiology, genetics, physiology, psychology, and economics. For example, one chapter discusses genetic influences and provides a readable introduction to the strategies of genetic investigation, and another chapter explains from a physiologic viewpoint how variations in the separate components of energy expenditure contribute to the regulation of body weight. The relation of obesity to lipoprotein metabolism is well summarized in one chapter, and there is a thorough review of randomized clinical trials that have assessed the role of physical activity in the management of obesity. The references in each chapter are generally up to date. Some of the chapters make explicit the connections between obesity and cardiovascular problems, whereas others focus on more general insights into the problem of obesity.

Inconsistent editing and typographic errors will irritate the careful reader. Several figures have legends that are inadequate or contain errors (e.g., a mislabeling of the sexes). Authors cited in the text are occasionally misidentified. The organization of the chapters is not entirely logical, although the chapter titles in the table of contents will suffice to guide readers to topics of interest. The book's index, on the other hand, provides uneven and skimpy coverage of most topics. Many of the entries are specific drugs indexed by their generic names. (Is it peculiar that one drug alone is indexed by its trade name?)

Missing from the book altogether is any mention of surgical options for the management of extreme obesity, and there is no discussion of how the gestational environment (nongenetic) might contribute to obesity, abnormal body-fat distribution, or insulin resistance in offspring. Several authors briefly mention waist circumference, the waist-to-hip ratio, or skin-fold measurements, but the book does not discuss in detail low-cost, simple anthropometric methods or measurement standards for use in clinical and epidemiologic settings. One author suggests (incorrectly) that dual-energy x-ray absorptiometry can be used to distinguish between intraabdominal fat and subcutaneous abdominal fat.

Thanks to the multidisciplinary basis of this book, clinicians and public health planners with an interest in obesity will probably gain some eye-opening insights. They should read it carefully, however. If they are unsure of the validity of the information, they should check the primary sources. Readers seeking current recommendations in this area may wish to consult Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults, from the National Institutes of Health (Obesity Research 1998;6:Suppl 2, or http://www.nhlbi.nih.gov/guidelines/obesity/ob_gdlns.htm), Obesity — Preventing and Managing the Global Epidemic, from the World Health Organization (Geneva, 1998, document WHO/NUT/NCD/98.1), and Obesity in Scotland: Integrating Prevention with Weight Management, from the Scottish Intercollegiate Guidelines Network (http://www.show.scot.nhs.uk/sign/sign8inf.htm). These compendiums are shorter and more carefully edited than the book from the American Heart Association. However, none of these alternative sources will provide the excitement of reading about the obesity problem from different intellectual perspectives.

Henry S. Kahn, M.D.
National Center for Chronic Disease Prevention and Health Promotion, Atlanta, GA 30341-3717