Will You Gain Weight If You Have Asthma?

Question

Is there any connection between asthma and gaining weight? My fiancé who is an asthmatic since the past couple of years has been complaining that she is putting on a lot of weight. I understand that if you have Asthma it is difficult to do your exercises in spite of which she still does work outs at least 3 or 4 times a week and follows a healthy diet but nothing seems to do her any good. Any advice would be welcome.