Shortness of breath, wheezing, coughing, and a tight chest, are classic signs that the airways are swollen and a severe asthma attack is pending. The key to thwarting such an attack is early recognition and treatment of symptoms, before they become a life-threatening episode. However, there is no catch-all approach to disease management.
According to a nationwide trial run by clinicians across Japan and analyzed by statisticians at the Translational Research Center for Medical Innovation (TRI) in Kobe, the warning signs that precede a full-blown asthma attack, which differ between patients, generally fall into three distinct sets. These patterns, or ‘clusters’, are broadly characterized by how quickly symptoms worsen in the hours and days leading up to emergency hospitalization — and for each cluster, the best way to prevent another exacerbation is different.
Optimal disease control will therefore require physicians to recognize a person’s risk factors, and then tailor treatment and medications, says study lead Hiroshi Tanaka, director of the NPO Sapporo Cough Asthma and Allergy Center.
Tanaka and his colleagues recruited 190 patients from emergency rooms in hospitals across Japan, from Kyushu to Hokkaido. Half had a prior history of hospitalization for asthma episodes, the other half had just experienced their first severe attack. The researchers analyzed self-reported symptoms and behaviors in the two weeks leading up to hospital admission, and found that patients could be grouped into three general clusters.
In one cluster of 80, patients went from having moderate symptoms to needing to be hospitalized within less than eight hours. These patients tended to be younger, leaner, with a tendency toward clinical depression and smoking, and a likelihood of having stopped taking anti-asthma medications. A young patient who gets rapidly worse may thus benefit from better drug compliance.
A second cluster of 76 mostly middle-aged and older individuals generally stuck to their medications but had poor perception of any breathing problems; these patients landed in the hospital around two days after an initial flare-up. In this cluster improved monitoring of breath strength could help.
The third cluster of 34 patients seemed to have good awareness and control of their asthma, yet their daily asthma symptoms just got worse over the course of more than a week until reaching the point of hospitalization. These patients may require higher drug doses.
The findings point to the need to consider entire health histories when deciding how best to prevent future asthma attacks. “Allergists, pulmonologists and primary care doctors should take note,” Tanaka says. Depending on the patient’s symptoms and disease trajectory, “we suggest different education and management strategies.”
- Tanaka, H., Nakatani, E., Fukutomi, Y., Sekiya, K., Kaneda, H. et al. Identification of patterns of factors preceding severe or life-threatening asthma exacerbations in a nationwide study. Allergy 73, 1110–1118 (2018). | article
About the Researcher
Hiroshi Tanaka, Director, NPO Sapporo Cough Asthma and Allergy Center
Hiroshi Tanaka is a respiratory specialist who treats and studies asthma, allergies and chronic obstructive pulmonary disease. He was an associate professor at the Sapporo Medical University School of Medicine before opening the Idaimae Minami Yojo Naika Clinic, in 2011, and the Sapporo Cough Asthma Allergy Center (SCAAC), in 2012. Tanaka currently serves as director of SCAAC, a non-profit organization that specializes in developing new diagnostic methods and treatments for patients with respiratory illnesses.