It is more than a hundred years since Parry,1 Graves2 and Basedow3 first accurately described hyperthyroidism and called attention to some of the cardiovascular derangements present in this condition, but it was not until twenty-five years ago that clinical calorimetry began to be widely adopted as an aid in the diagnosis of exophthalmic goiter. Today the determination of the basal metabolic rate is the laboratory procedure most frequently used in the differential diagnosis of disorders of the thyroid gland.
Disturbances of the thyroid gland, however, are not the only conditions producing changes in the basal metabolic rate. The basal metabolic rate is elevated not only in hyperthyroidism, but also in leukemia, congestive heart failure, some cases of hypertension, fevers, polycythemia vera and various glandular disturbances. Furthermore, hypopituitarism and malnutrition as well as hypothyroidism may lower the basal metabolic rate. For these reasons attempts have been made to