Clinical remission of asthma: what lies beyond?

Asthma can be a debilitating disease with a major impact on quality of life and an increased risk of developing severe airway remodelling and non-fully reversible airflow obstruction. In the last decades, effective pharmacological treatments and management strategies have been developed for this disease. Yet, at the present time, asthma remains a treatable but not a curable disease.

It is not therefore surprising that much effort is being put into studying the risk factors associated with the inception and progression of asthma, since understanding these factors represents the first necessary step for developing effective prevention strategies. In this respect, the increase in the incidence and prevalence of asthma over the last decades has not only produced a general awareness of the public health burden associated with the disease, but it has also provided the scientific rationale for expecting a major role of environmental factors in its development. However, the epidemiological identification of these disease determinants has not proved to be an easy task. While profiles of risk factors for asthma have been identified, the exact mechanisms by which they operate are far from being fully understood for many (or most) of them. In addition, many of these factors are likely to be involved in complex gene-by-environment interactions and to be differentially linked to different asthma phenotypes. This complexity has limited the implementation of effective interventions to reduce the incidence of asthma and, to date, there is no conclusive programme of primary prevention for this disease.

To complicate things even more, remarkable paradoxes have emerged from recent research. Factors that are known to exacerbate or trigger asthma, such as exposure to endotoxin¹ or pets,² appear to be somewhat protective if they occur …