Book Review

Osteoporosis: Diagnostic and therapeutic principles

N Engl J Med 1996; 335:1615-1616November 21, 1996

Article

Osteoporosis: Diagnostic and therapeutic principles
(Current Clinical Practice.) Edited by Clifford J. Rosen. 297 pp., illustrated. Totowa, N.J., Humana Press, 1996. $99.50. ISBN: 0-89603-374-0

Osteoporosis is a common disease, but it is not simple. The goal of this textbook is to help primary care physicians understand and apply the rapidly growing body of knowledge derived from bone-related research. The first two sections discuss physiology and pathophysiology, the next two sections deal with diagnosis and treatment, and the final section presents cases with discussions.

The valuable section on treatment begins with a brief review of clinical decision making, followed by succinct chapters on calcium intake for each stage of the life cycle and on estrogen treatment. The chapter on drug treatment, particularly the concluding guidelines, is an excellent example of a concise, unbiased review that is worthwhile reading for primary care physicians. This discussion stands in contrast to the algorithm at the end of the book, which is simplistic, does not take into account the difference between osteoporosis and established osteoporosis (low bone density with fractures), and advocates unproven, expensive follow-up.

The organization of the book makes it difficult to locate some information. For example, discussions of traditional epidemiologic issues such as risk factors are scattered among chapters on pathophysiology and case reports instead of being in the epidemiology chapter. On the other hand, some issues (calcium, vitamin D, and estrogen) are discussed so often that they are redundant, especially in the case discussions.

Some complicated but essential concepts are not presented as clearly as they deserve. For example, physicians should know the expected time course of improvement in bone density with the antiresorptive drugs. When osteoclastic resorption is blocked, the cavities that were beginning to fill with new bone will keep filling for several months until they are full; during this time, bone mass increases, but bone formation subsequently stops, and the bone mass plateaus. The increase in bone mass is not due to an anabolic effect. This physiologic process is nicely described in the chapter on estrogen but is misrepresented in the chapter on calcium and is not mentioned in the chapters on bone remodeling and pathophysiology.

Another important concept is that information on bone density alone does not help predict fractures; instead, it must be interpreted in the context of the patient's age, the presence or absence of a history of fractures, and other risk factors. The chapter on the interpretation of bone-density data does address the problem but uses jargon (e.g., RLFP for “remaining lifetime fracture probability”) that is unfamiliar and confusing.

The prevalent misconception that calcitriol increases bone mass is based on findings in calcium-depleted patients and studies in which patients receiving calcitriol had stable bone mass whereas those receiving placebo had decreased bone mass. This misconception is perpetuated in the chapter on vitamin D, which states that bone density increased in a large study. In that study, however, bone density was not measured.

To be practical, a textbook should not require the reader to consult the references in order to obtain helpful information. This book should have included specific exercises for back strength, the brief questionnaire on calcium intake, the table for converting bone density to the lifetime risk of fracture, and the checklist of risk factors for falls.

In summary, this book contains plenty of useful information about osteoporosis, but it could have been presented in a way that would have made it easier for primary care physicians to use.

Susan M. Ott, M.D.
University of Washington, Seattle, WA 98195