[Why do we look at asthma through the keyhole?]

As happens with the rest of pathology, the study of asthma has been traditionally conducted from postulates set by reductionist science. That model still provides answers to theoretical and practical questions that establish diseases, but does not offer us a complete view of their complexity and multidimensionality. To overcome this limitation has emerged medicine directed towards systems based on the application of biological systems concepts and tools. Biological systems is a cross-disciplinary strategy which, from the data generated by the "-omic" sciences, helps to relate the elements of an organism or biological system, to understand the properties arising from the same and to generate mathematical models capable of predicting their dynamic behaviour. The application of biological systems to asthma starts is starting to make ground. The main challenge today is to understand the need to change focus. The starting point is to abandon the idea that asthma is exclusively an airways disease and considering that the whole lung is involved and, even more, the possibility that it is, at least in part, a systemic process. In view of our current limitations, to understand asthma and design personalised treatment strategies for each patient, requires thinking of systems medicine.