Airflow Limitation in Morbidly Obese, Nonsmoking Men

doi:10.1059/0003-4819-112-11-828

Airflow Limitation in Morbidly Obese, Nonsmoking Men

I. Rubinstein, MD;
N. Zamel, MD;
L. DuBarry, RPT; and
V. Hoffstein, MD

Abstract

Study Objective: To determine the effect of obesity on pulmonary function.

Design: Case-control study, using nonobese, age- and weight-matched nonsmokers.

Setting: Metabolic and obesity clinics of two major teaching hospitals.

Patients: One hundred and three obese, lifelong nonsmokers without cardiopulmonary disease.

Controls: One hundred and ninety healthy, nonobese nonsmokers recruited from among hospital personnel.

Measurements and Main Results: Complete pulmonary function measurements in all patients and controls. These measurements included maximum expiratory flow-volume curve, lung volumes and airway resistance using body plethysmograph, single-breath diffusing capacity for carbon monoxide, and total lung capacity using the helium dilution technique. Obese persons were found to have lower functional residual capacity, expiratory reserve volume, and total lung capacity by helium dilution than nonobese controls. In addition, residual volume and diffusing capacity were higher in the obese group. Finally, we found that obese men, but not women, had reduced maximum expiratory flow rates at 50% and 75% of exhaled vital capacity.

Conclusion: Obesity may contribute independently of smoking habits to chronic airflow limitation in men.

Article and Author Information

From St. Michael's Hospital, the Toronto Hospital, and the University of Toronto, Toronto, Ontario. For current author addresses, see end of text.
Requests for Reprints: Victor Hoffstein, MD, St. Michael's Hospital, 30 Bond Street, Toronto, Ontario M5B 1W8.
Current Author Addresses: Dr. Rubinstein: Pulmonary and Critical Care Medicine Section, Department of Internal Medicine, University of Nebraska Medical Center, 42nd and Dewey Avenue, Omaha, NE 68105-1065.

Dr. Zamel: Mount Sinai Hospital, Department of Medicine, 600 University Avenue, Toronto, Ontario.

Dr. Hoffstein and Mrs. DuBarry: St. Michael's Hospital, 30 Bond Street, Toronto, Ontario.