Reducing the burden of asthma: time to set research and clinical priorities

Abstract

There is a substantial global burden of asthma in terms of prevalence, morbidity, mortality, and cost. It has been estimated that there are over 300 million people with asthma worldwide, most of whom do not have well controlled symptoms. Long-term trends in country-specific asthma mortality have been dominated by the effects of treatments, with β-adrenoceptor agonist-related increases in mortality in the 1960s and 1980s, and a progressive reduction in mortality from the 1990s into the 21st century attributed to the widespread use of inhaled corticosteroids (ICS). 1 Pavord ID Beasley R Agusti A et al. After asthma: redefining airways diseases. Lancet. 2018; 391: 350-400 Summary Full Text Full Text PDF PubMed Scopus (589) Google Scholar Although the asthma mortality rate has continued to fall in some countries and regions, the estimated global mortality rate has not changed appreciably since 2006. 2 Ebmeier S Thayabaran D Braithwaite I Bénamara C Weatherall M Beasley R Trends in international asthma mortality: analysis of data from the WHO Mortality Database from 46 countries (1993–2012). Lancet. 2017; 390: 935-945 Summary Full Text Full Text PDF PubMed Scopus (169) Google Scholar This absence of change suggests that the progress made in the previous 2 decades might have stalled, and that better implementation of proven current management strategies, together with novel approaches, are required to achieve further reductions in mortality and, more generally, the burden of asthma. The genetics of asthma and the promise of genomics-guided drug target discoveryAsthma is an inflammatory airway disease that is estimated to affect 339 million people globally. The symptoms of about 5–10% of patients with asthma are not adequately controlled with current therapy, and little success has been achieved in developing drugs that target the underlying mechanisms of asthma rather than suppressing symptoms. Over the past 3 years, well powered genetic studies of asthma have increased the number of independent asthma-associated genetic loci to 128. In this Series paper, we describe the immense progress in asthma genetics over the past 13 years and link asthma genetic variants to possible drug targets. Full-Text PDF Advances in understanding and reducing the burden of severe asthma in childrenSevere asthma in children is rare, accounting for only a small proportion of childhood asthma. After addressing modifiable factors such as adherence to treatment, comorbidities, and adverse exposures, children whose disease is not well controlled on high doses of medication form a heterogeneous group of severe asthma phenotypes. Over the past decade, considerable advances have been made in understanding the pathophysiology of severe therapy-resistant asthma in children. However, asthma attacks and hospital admissions are frequent and mortality is still unacceptably high. Full-Text PDF Primary prevention of asthma: from risk and protective factors to targeted strategies for preventionAsthma is a complex disease that often starts in childhood. Genomic and environmental factors as well as aberrant immune maturation early in life can contribute to the onset of disease, with great disparity over time and geographical regions. Epidemiological studies have scrutinised environmental exposures and attempted to translate these exposures into prevention strategies. Some approaches for patients with asthma have been successful (eg, smoking ban, the Finnish Asthma Programme), and primary prevention of wheeze in pre-school children (age 0–5 years) by the supplementation of vitamin D or fish oil, or both, to pregnant women seems promising. Full-Text PDF