EC Pulmonology and Respiratory Medicine

The diagnosis of obstructive ventilatory impairment (OVI) is currently lacking worldwide consensus. This lack of agreement on the threshold for a significantly low ratio of forced expiratory volume in 1 second to forced vital capacity has led to ongoing debates and misperception among physicians and researchers. This review aims to update the definitions of OVI provided by scholarly societies, including the American Thoracic Society and European Respiratory Society (ATS/ERS), the Global Strategy for Prevention, Diagnosis, and Management of COPD (GOLD), and the Global Initiative for Asthma (GINA). Additionally, the review provides an overview of the rationales behind these definitions and highlights the challenges associated with spirometric indices and threshold selection. The call to action urges scholarly societies to standardize the criteria for diagnosing OVI. Two approaches were used by scholarly societies to define OVI: the physiological approach (ATS/ERS) and the operational approach (GOLD and GINA). Each approach utilizes different criteria and threshold values for diagnosing OVI, creating complexity for clinicians and researchers. The advantages and limitations of the physiological and operational approaches are discussed. The physiological approach offers increased specificity, early detection, and reduced false positives, but challenges in interpretation and limited application should be considered. The operational approach provides simplified diagnosis, aligns with clinical trial evidence, and facilitates screening and case finding. However, it increases the risk of misdiagnosis, it may lead to misclassification and challenges in interpreting results for different age groups, variability with sex and height, and potential misdiagnosis and adverse outcomes. It is recommended that ATS/ERS, GOLD, and GINA work towards proposing a standardized definition for OVI. By doing so, healthcare professionals can ensure consistent and effective diagnosis and management of OVI, ultimately improving patient care and outcomes

Keywords: Bronchial Asthma; Bronchial Obstruction; COPD; Diagnostic Criteria; Operational Approach; Physiological Approach; Spirometry

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