Diaphragm and body weight in emphysema.

The weight of the diaphragm has been investigated in 103 male patients and 81 female patients, and the relationship between body weight and emphysema has been assessed in 662 male and 431 female patients. Diaphragm weight is related to body weight in both male (r = + 0.76) and female patients (r = +0.77) and is relatively larger in the former. Dissecting the diaphragm free of fat or freeze drying it does not appreciably improve the relationship between body weight and diaphragm weight. Diaphragm weight is better related to body weight than body length and is diminished in emphysema. Patients with emphysema weigh less. This is apparent with only moderate grades of emphysema, and there is no further loss of body weight as emphysema in the lung becomes more severe. The loss of diaphragm weight not only reflects the loss of body weight that occurs in emphysema, but the diaphragm is also less in weight than predicted from body weight. The diaphragm also appears abnormal on gross inspection in some patients with emphysema. Heart weight and diaphragm weight are related, probably because both are related to body weight.