Key Point:

Severe malnutrition appears to cause emphysematous changes in the lungs.

CHICAGO—Using quantitative computed tomography (CT) of the chest, Canadian investigators have found structural and functional changes in the lungs of 14 patients with anorexia nervosa that suggest that severe malnutrition can cause emphysema.[1] Compared with 16 healthy controls, the patients with anorexia had significant decreases in their mean lung density, lung inflation, and lung surface area/lung volume (S/V) ratio.

In the anorexic patients, there were also strong correlations between body mass index and mean lung density, mean lung inflation, the S/V ratio, and the diffusing capacity of carbon monoxide. “These findings indicate that patients with anorexia lose lung tissue and become less able to exchange oxygen as they lose weight and become more malnourished,” lead investigator Harvey O. Coxson, PhD, explained.

Whether these emphysema-like changes are permanent is unclear, stressed Dr. Coxson, an Assistant Professor of Radiology at the University of British Columbia in Vancouver. If the changes are reversible, however, early nutritional therapy will become even more important for anorexic patients.

IMPLICATIONS FOR SMOKERS

The study’s results also have implications for smokers. “If malnutrition causes emphysema in patients with anorexia, it may contribute to emphysema in smokers,” said Dr. Coxson. “If so, nutritional treatment may slow the development of emphysema in smokers,” he added.

Notably, the anorexic patients in Dr. Coxson’s study were not anemic, and they were similar to the controls in age and pulmonary function; smoking was actually more common in the control group. No significant correlations were observed between chest CT findings and FEV1, forced vital capacity, total lung capacity, or maximum expiratory pressure.

Before quantitative CT was developed, direct examination of the lungs in animal models of starvation was the primary method used to assess the link between malnutrition and emphysematous changes. Some of the first and most important human data to support that link were obtained during the Nazi occupation of Warsaw, when Jewish residents were forced to live in the city’s poverty-stricken ghetto. At the time, Jewish physicians found that approximately 14% of the ghetto residents who died of starvation had emphysema at autopsy.

However, not all recent studies of anorexic patients have confirmed an association with emphysema, Dr. Coxson acknowledged. Thus, additional investigation is needed.

—Timothy Begany

Reference
1.Chan IH, Birmingham CL, Mayo JR, et al. The measurement of lung structural changes due to anorexia nervosa using computed tomography. Presented at: 89th Scientific Assembly and Annual Meeting of the Radiological Society of North America; December 3, 2003; Chicago, Ill.

Return to table of contents