Jae-Woo Kwon1, Heewon Jung2, Sae-Hoon Kim3, Yoon-Seok Chang3, You Sook Cho2, Dong-Ho Nahm4, An-Soo Jang5, Jung-Won Park6, Ho Joo Yoon7, Sang-Heon Cho3, Young-Joo Cho8, Byoung Whui Choi9, Hee-Bom Moon2, Tae-Bum Kim10. 1. Department of Allergy and Clinical Immunology, Kangwon National University College of Medicine, Chuncheon, South Korea. 2. Department of Allergy and Clinical Immunology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea. 3. Department of Internal Medicine, Seoul National University College of Medicine, Seoul, South Korea. 4. Department of Allergy and Clinical Immunology, Ajou University School of Medicine, Suwon, South Korea. 5. Department of Internal Medicine, Soonchunhyang University Bucheon Hospital, Soonchunhyang University School of Medicine, Bucheon, South Korea. 6. Department of Internal Medicine and Allergy Institute, Yonsei University College of Medicine, Seoul, South Korea. 7. Department of Internal Medicine, Hanyang University College of Medicine, Seoul, South Korea. 8. Department of Internal Medicine, Ewha Womans University College of Medicine, Seoul, South Korea. 9. Department of Internal Medicine, Chung-Ang University College of Medicine, Seoul, South Korea. 10. Department of Allergy and Clinical Immunology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea. Electronic address: tbkim@amc.seoul.kr.
Abstract
BACKGROUND: Low forced expiratory volume in 1 s (FEV1) is a risk factor for asthma exacerbations (AEs). We aimed to determine if asthma control could reduce the future risk of AEs in patients with low FEV1. This study was conducted to evaluate the future risks of AEs within six months according to Asthma Control Test™ (ACT) score and FEV1. METHODS: A total of 565 patients with asthma were enrolled from the COREA cohort. The ACT score, lung function test, and number of AEs were assessed at baseline, three-month follow-up, and six-month follow-up with conventional asthma treatments by asthma specialists in real clinical settings. RESULTS: Female sex, low ACT score, low FEV1, low FVC, and AE history in the previous three months were related with increased AEs within six months. AEs during six-month follow-up occurred in 24% of patients with ACT <20 and FEV1 < 60% at baseline. Among patients with an ACT score ≥20, 3.4% of patients with an FEV1 < 2.16 L and 9.8% of patients with FEV1 ≥ 2.16 L had experienced AEs (P = 0.01), although no differences were observed in the presence of AEs within six months according to the predicted FEV1 (FEV1 ≥ 60% vs. FEV1 < 60%, 5.66% vs. 8.51%, P = 0.65). CONCLUSION: Patient with low FEV1 seemed to show higher risk of AEs than those with near-normal FEV1 despite ACT score ≥20 and asthma treatments. Therefore, treatment strategies that prevent AEs are needed in high-risk asthmatic patients.
BACKGROUND: Low forced expiratory volume in 1 s (FEV1) is a risk factor for asthma exacerbations (AEs). We aimed to determine if asthma control could reduce the future risk of AEs in patients with low FEV1. This study was conducted to evaluate the future risks of AEs within six months according to Asthma Control Test™ (ACT) score and FEV1. METHODS: A total of 565 patients with asthma were enrolled from the COREA cohort. The ACT score, lung function test, and number of AEs were assessed at baseline, three-month follow-up, and six-month follow-up with conventional asthma treatments by asthma specialists in real clinical settings. RESULTS: Female sex, low ACT score, low FEV1, low FVC, and AE history in the previous three months were related with increased AEs within six months. AEs during six-month follow-up occurred in 24% of patients with ACT <20 and FEV1 < 60% at baseline. Among patients with an ACT score ≥20, 3.4% of patients with an FEV1 < 2.16 L and 9.8% of patients with FEV1 ≥ 2.16 L had experienced AEs (P = 0.01), although no differences were observed in the presence of AEs within six months according to the predicted FEV1 (FEV1 ≥ 60% vs. FEV1 < 60%, 5.66% vs. 8.51%, P = 0.65). CONCLUSION:Patient with low FEV1 seemed to show higher risk of AEs than those with near-normal FEV1 despite ACT score ≥20 and asthma treatments. Therefore, treatment strategies that prevent AEs are needed in high-risk asthmatic patients.