Obesity can mimic asthma, it affects respiratory symptoms and lung mechanics, but it can also overlap, of course. Asthma is more often diagnosed in obese (but could be misdiagnosed, on basis of exertional breathlessness?).

Concern is the pro-inflammatory action of adipose tissue.

Maternal obesity (and gestational weight gain) in pregnancy appears to be a risk factor – each BMI increase of 1kg/m2 increases risk by 2-3%!

Obesity is one of the factors associated with fatal asthma attacks (but note socioeconomic confounding).

Weight reduction leads to improved lung function, health status, symptoms and morbidity in adults. Not yet proven in adolescents.

Slightly increased risk of acute asthma attacks in obese adults and school age children.