Some Clinical Considerations of Basal Metabolism
By metabolism, we mean the sum total of chemical change occurring in the organism. This includes not only processes of oxidation and reduction, but also synthesis and degradation of a large number of chemical compounds. Our total knowledge of the finer metabolic changes is meager and even the knowledge of the metabolism of hormones which have been known in relatively pure or crystalline forms for some time is not understood in any degree of completeness. Of the many measures of metabolism, the basal metabolic rate has become one of the most common and for that reason is of great practical significance. This consideration of the basal metabolic rate is for the main purpose of emphasizing the simple fact that it is a symptom and is of significance only in consideration of the total clinical picture. The metabolic rate is as much a symptom as the pulse rate or body temperature and not more specific.
The typical case of hyperthyroidism is always associated with hyper-metabolism. In Grave’s disease, remissions may occur, however, and at such times the basal metabolic rate may fall to normal. It is for this reason that one other factor is more important in the diagnosis of hyperthyroidism than an elevated basal metabolic rate, namely, a good history. In some of these cases, the presence of goiter, the facial expression so typical of the disease, some tachycardia, tremor or skin changes usually lead to the diagnosis. Iodine remissions may bring about the same changes. In some instances. . .