Diagnostic Accuracy of FEF_25-75 for Bronchial Hyperresponsiveness in Patients with Suspected Asthma and/or Allergic Rhinitis: A Systematic Review and Meta-analysis

Background: Some studies have suggested that the forced expiratory flow between 25 and 75% of vital capacity (FEF_25-75) can be used as an early marker of bronchial hyperresponsiveness (BHR) in asthma and allergic rhinitis (AR), but is highly variable. Here, we aimed to assess whether the FEF_25-75 can be used to diagnose BHR in patients with asthma-like symptoms and AR.

Methods: PubMed, EMBASE, Web of Science, Wiley Online Library, Cochrane Library, SinoMed, CNKI, and Wanfang Data were searched to acquire eligible studies. Articles published before 30 Sep 2023 were included. Quality Assessment of Diagnostic Accuracy Studies 2 was used to evaluate the risk of bias and application concern of the included articles. Data were pooled using random-effects models. The univariable meta-regression and subgroup analyses were used to explore the sources of heterogeneity.

Results: Twenty-five studies were included, describing 12,310 patients with asthma-like symptoms and AR. In terms of the FEF_25-75, the pooled sensitivity and specificity were 0.56(95% CI 0.47-0.65) and 0.86 (95% CI 0.80-0.90), respectively. In addition, the pooled diagnostic odds ratio (DOR) was 8.00 (95% CI 6-10) and the area under the curve (AUC) was 0.80 (95% CI 0.76-0.83). Furthermore, we performed the univariable meta-regression and subgroup analyses, indicating that the disease types and ethnicity may be the sources of heterogeneity.

Conclusion: This meta-analysis showed that if BPT cannot be performed a value of FEF_25-75 < 65% of predicted may suggest the presence of BHR in patients with suspected asthma and /or AR.