NATURAL HISTORY VERSUS CLINICAL HISTORY

Clinicians should focus on two characteristics of any disorder: natural history and clinical history. The former is defined by manifestations and outcomes that typically occur in the absence of management. The latter is the course of the disease when health professionals and even patients themselves intervene. The concepts are clearly related in a number of ways. One challenging aspect of this inter-relationship results from improved clinical history: as patients live longer, “new”, age-dependent features of the disease emerge.

These concepts are well illustrated by Marfan syndrome (MFS). This autosomal dominant heritable disorder of connective tissue is not rare—with a prevalence of one in a few thousand—and has major cardiovascular involvement.1 2 Myxomatous deterioration of the atrioventricular valves leads to prolapse in the majority and moderate regurgitation or worse in some. Dysrrhythmia is common.3 A dilated cardiomyopathy occurs in some. The most characteristic and troublesome feature is dilatation of the aortic root, which predisposes to dissection and sudden death, and to chronic aortic regurgitation owing to stretching of the commissures. Other organ systems and tissues are affected, especially the skeleton, eye, lung and dura.1 As patients are living longer, involvement of other organs is becoming evident.4

NATURAL HISTORY

Few good studies of life expectancy, one important aspect of natural history, have been performed in MFS, and they have limitations. The best study, published in the early 1970s, retrospectively examined records of patients who did not benefit from any effective medical or surgical treatment of their cardiovascular disease.5 The average age of death was in the fourth and fifth decades, almost always from heart failure from aortic or mitral regurgitation or from acute dissection. In retrospect it is likely that milder cases of MFS were not ascertained, and some of the more severe cases may have had heterogeneous disorders …