Waist-to-Hip Ratio Linked to Gas Exchange

Canadian researchers say large waist-to-hip ratios in the morbidly obese are associated with impaired pulmonary gas exchange.

McGill University researchers gathered arterial blood samples from 25 morbidly obese patients who were scheduled for bariatric surgery and recorded age, body mass index, body fat percentage, waist circumference and waist-to-hip ratio.

Large waist-to-hip ratios indicate substantial portions of fat mass surrounding the thorax, which could lead to ventilation abnormalities. While there was no relationship between body mass index and pulmonary gas exchange, researchers found both oxygenation problems, as well as minor ventilatory constraints, in the participants.

Also noted was that all of the men had larger waist-to-hip ratios and were more likely to have a poorer gas exchange, compared with the women.

Researchers concluded in the journal Chest that a significant part of the blood-gas status in all participants was associated with their waist-to-hip ratio.