The Effect of Obesity on Asthma
Obesity has long been recognized as a predisposing factor for several chronic diseases like heart disease, diabetes, and has globally affected people in many parts of the world. However, there is increasing evidence that obesity is also closely related to asthma. It has been observed that obesity is not only associated with a greater risk for asthma but is also responsible for more severe symptoms of asthma. But, whether obesity causes asthma or asthma predisposes a person towards obesity is a question that does not have a very clear answer. In fact, it has been observed that obesity related asthma responds differently to medications. However, one thing is clear that reduction in weight produces immediate decrease in the severity of asthma symptoms.
The Role of Obesity
Several reasons have been put forward for the close link between obesity and asthma. There is no doubt that obesity in general leads to more discomfort in breathing even though there may not be an underlying respiratory disease. On the other hand, it is a well-known fact that people with asthma tend to be less physically active which in turn tends to make them obese.
- Asthma is characterized by inflammation, tightening of muscles around the airway and hypersensitivity. This leads to difficulty in breathing. Obesity in itself causes problems in breathing as lungs have less capacity.
- In addition to this, more effort is required by the obese to lift the chest wall as it has too much adipose or fat tissue.
- Obesity in the upper body or around the abdomen imposes greater respiratory load as diaphragm dysfunction is caused by deposits of adipose tissue around the abdomen.
- Obesity is also associated with chronic inflammation, a factor that it has common with asthma. However, the underlying mechanisms are not clearly understood.
- Several hormones like leptin released from adipose tissue lead to a tendency towards inflammation. Though no direct relationship has been observed between leptin and asthma, yet children who are obese as well as asthmatic tend to have higher levels of leptin.
- Another possible reason is that obesity often leads to GERD which in turn worsens asthma symptoms.
- Besides this, obstructive sleep apnea is closely related to obesity and worsens night time symptoms for asthma sufferers.
- One of the reasons why the obese face more severe symptoms is that their reaction to bronchoconstriction is much more intense leading to more severe asthma symptoms.
- Peripheral airways of the obese are less in diameter, thereby leading to an aggravated response to constriction.
Implication for Management of Asthma
All the factors that influence the relation between obesity and asthma may not be absolutely clear, but compelling evidence does provide another strong reason to cut down on those extra kilos. Weight loss not only reduces the severity of asthma symptoms but also improves one’s response to medications thereby leading to a better quality of life for asthmatics. Thus, instead of merely increasing medication for management of asthma, a concerted effort should also be devoted to weight management through changes in lifestyle as part of treatment for asthma.
Written by: Nandita tripati
Date last updated: January 07, 2015