Study Finds Baseline Forced Oscillation Technique Effective in Predicting Exacerbation Risk in Adults with Asthma

The prospective research, conducted over 12 months, showed that R20 may be an effective predictor of future exacerbations in asthma patients. The findings could enhance the evaluation of adults with asthma who have normal FEV1 levels.

"Our findings established the baseline FOT as an important tool for predicting clinical remission in adults with asthma over 12 months," the researchers wrote. "Notably, FOT parameters, especially resistance at 20 Hz (R20), effectively differentiated between those who achieved clinical remission and those who did not. Lower R20 values were significantly linked to clinical remission, with an adjusted odds ratio of 0.32."

Asthma exacerbations can significantly impact patients' quality of life, leading to increased healthcare costs and reduced lung function. Traditional methods of monitoring asthma rely on FEV1 measurements, which can sometimes fail to capture the complexity of the disease in certain patients.

The forced oscillation technique (FOT) is a minimally invasive method for assessing asthma during resting ventilation. However, its effectiveness in long-term evaluations, such as monitoring clinical remission, is still not well understood. Therefore, Yoshito Miyata, Showa University School of Medicine, Tokyo, Japan, and colleagues aimed to evaluate asthma clinical remission over time and identify parameters from baseline FOT that predict remission at the 12-month mark.

For this purpose, the researchers enrolled adult patients with asthma at their university hospital from April 2022 to May 2023 in a prospective observational study. Participants were evaluated over 12 months to determine if they met the clinical remission criteria: an asthma control test score of ≥20 at both enrollment and 12 months, no exacerbations during that period, and no regular oral corticosteroid use. The FOT parameters collected at enrollment were then analyzed for their association with clinical remission.

The following were the key findings of the study:

• Ninety-four asthma patients completed the study and were divided into clinical and non-clinical remission groups.
• Comparing pulmonary function tests, including FOT, revealed significant differences in resistance at 5 Hz and 20 Hz (R20), while there were no differences in FEV1.
• Multivariate logistic regression analysis indicated that R20 was linked to clinical remission, with adjusted odds ratios of 0.32 for R20.

The study emphasizes the value of baseline forced oscillation technique measurements, particularly R20, in predicting future exacerbations in adults with asthma. These insights could transform clinical practices, allowing for more effective monitoring and management of asthma, especially in patients with normal lung function.

"As the medical community continues to seek innovative ways to enhance asthma care, FOT may play a pivotal role in shaping future treatment strategies," the researchers concluded.

Reference:

Miyata Y, Tanaka A, Ebato T, Kashima A, Nojo M, Matsunaga T, Kaneko K, Okazaki T, Ohta S, Homma T, Watanabe Y, Kusumoto S, Suzuki S, Sagara H. Baseline forced oscillation technique predicting lack of exacerbations in adult with asthma: A 12-month prospective. Ann Allergy Asthma Immunol. 2024 Oct 4:S1081-1206(24)01553-9. doi: 10.1016/j.anai.2024.09.018. Epub ahead of print. PMID: 39370038.