Effect of weight reduction on respiratory function and airway reactivity in obese women.
BACKGROUND
Population-based studies have documented an association between obesity and an increased prevalence of asthma in women.


METHODS
We prospectively studied 58 obese women with a body mass index of > 30 kg/m(2), 24 of whom had asthma, who were enrolled in an intensive 6-month weight loss program to determine whether loss of body mass would be correlated with improvements in bronchial reactivity, lung function, and disease-specific health status.


RESULTS
Patients lost an average of 20 kg over the 6-month period. For every 10% relative loss of weight, the FVC improved by 92 mL (p = 0.05) and the FEV(1) improved by 73 mL (p = 0.04), however, bronchial reactivity did not significantly change with weight loss (p = 0.23). Patients who lost > 13% of their pretreatment weight experienced improvements in FEV(1) (p = 0.01), FVC (p = 0.02), and total lung capacity (p = 0.05) compared to patients in the lowest quartile who failed to lose significant amounts of weight. Neither group experienced any significant change in methacholine responsiveness (p = 0.57). Patients who completed the 6-month weight loss program experienced improvements in respiratory health status, irrespective of weight loss.


CONCLUSIONS
We concluded that weight loss can improve lung function in obese women, however, the improvements appear to be independent of changes in airway reactivity.
Aaron
Shawn D
SD
Department of Medicine, University of Ottawa, Ottawa, ON, Canada. saaron@ottawahospital.on.ca
Fergusson
Dean
D
Dent
Robert
R
Chen
Yue
Y
Vandemheen
Katherine L
KL
Dales
Robert E
RE
D000328:Adult; D000403:Airway Resistance; D001249:Asthma / Q000150:complications / Q000175:diagnosis*; D015992:Body Mass Index; D001835:Body Weight; D016535:Bronchial Hyperreactivity / Q000503:physiopathology*; D004038:Diet, Reducing; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000175:diagnosis*; D011336:Probability; D011446:Prospective Studies; D012129:Respiratory Function Tests; D012307:Risk Factors; D012494:Sampling Studies; D014797:Vital Capacity; D015431:Weight Loss