Cough and asthma diagnosis: physicians’ diagnosis and treatment of patients complaining of acute, subacute and chronic cough in rural areas of Japan

Akira Yamasaki¹, Keichi Hanaki², Katsuyuki Tomita³, Masanari Watanabe¹, Yasuyuki Hasagawa¹, Ryota Okazaki¹, Miki Yamamura¹, Kouji Fukutani⁴, Yuji Sugimoto⁵, Kazuhiro Kato⁴, Masahiro Kodani⁶, Toshikazu Ikeda⁷, Tatsuya Konishi⁸, Yuji Kawasaki⁹, Hirokazu Tokuyasu⁹, Hiroki Yajima³, Hitoshi Sejima¹⁰, Takeshi Isobe¹¹, Eiji Shimizu¹, SAN-IN Asthma Research Group

¹Third Department of Internal Medicine, ²Department of Pediatrics, Tottori University, Japan; ³Department of Respiratory Medicine, Hakuai Hospital, Japan; ⁴Department of Respiratory Medicine, San-in Rosai Hospital,  Japan; ⁵Department of Respiratory Medicine, Tottori Prefectural Central Hospital, Japan; ⁶Department of Respiratory Medicine, Tottori Red Cross Hospital, Japan; ⁷Department of Respiratory Medicine, National Organization, Matsue Hospital, Japan; ⁸Department of Respiratory Medicine, Matsue City Hospital, Japan; ⁹Department of Respiratory Medicine, Matsue Red Cross Hospital, Japan; ¹⁰Department of Pediatrics,  ¹¹Department of Internal Medicine, Shimane University, Shimane, Japan

Background: Cough is one of the most common reasons for visiting a clinic. The causes of cough differ according to the duration of cough. Infectious disease is commonly observed in acute cough while noninfectious disease is commonly observed in chronic cough. On the other hand, cough is frequently observed in patients with asthma/cough variant asthma (CVA).

Objective: In this study, we investigated the causes of cough in a rural region in Japan and the clinical examination and treatment for the patients diagnosed as asthma/CVA.

Methods: We analyzed 124 patients who complained of cough.

Results: The most common reason for acute cough was respiratory tract infection while asthma/CVA is the most common reason for subacute and chronic cough. The diagnostic procedure for asthma/CVA depends on clinical symptoms in asthmatic patients with acute cough. While in asthmatic patients with subacute and chronic cough, diagnosis of asthma depends on clinical examinations including chest radiogram, immunoglobulin E, white blood cells counts, sputum examination or spirometry as well as symptoms. For the treatment of asthma, the use of long-acting β₂-stimulant was dominant in asthmatic patients with acute cough while the use of leukotriene receptor and inhaled corticosteroid were dominant in asthmatic patients with subacute or chronic cough.

Conclusions: Diagnosis and treatment for asthma differs according to the duration of cough. Simple guidelines for asthma/CVA according to the duration of cough might be necessary for diagnosis and treatment of asthma/CVA for general physicians especially in rural areas.

Keywords: cough, diagnostic procedures, cough variant asthma, asthma