Small airways dysfunction: The importance of utilising Z-scores to define MMEF abnormalities in clinical practice
Background: The small airways comprise the largest cross-sectional area of the lungs, however, assessing and reporting abnormalities for this region of the bronchial tree has been practically and scientifically uncertain. Methods: Using routinely collected spirometry data for patients with either as...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2023-10-01
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| Series: | Heliyon |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2405844023079525 |
| _version_ | 1797646463189123072 |
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| author | Mohammed A. Almeshari Nowaf Y. Alobaidi Elizabeth Sapey Robert A. Stockley James A. Stockley |
| author_facet | Mohammed A. Almeshari Nowaf Y. Alobaidi Elizabeth Sapey Robert A. Stockley James A. Stockley |
| author_sort | Mohammed A. Almeshari |
| collection | DOAJ |
| description | Background: The small airways comprise the largest cross-sectional area of the lungs, however, assessing and reporting abnormalities for this region of the bronchial tree has been practically and scientifically uncertain. Methods: Using routinely collected spirometry data for patients with either asthma or COPD, the accuracy of % predicted values for defining small airways dysfunction was assessed. A z-score of ≤ −1.645 of the maximal-mid expiratory flow (MMEF) was used as the gold standard for defining abnormality in the small airways. Results: Records of 3396 patients were included in the analysis. The false positive (FP) rates were 24.6 %, 16.1 %, 11.5 %, or 7.9 % when the % predicted value of 80 %, 70 %, 65 %, or 60 % were used, respectively. Sex, age, and BMI were associated with FP rates. Males were more likely to be categorised as FP with odds ratio (OR) between 1.10 and 1.49 across % predicted groups. Age was associated with FP rates with an OR between 1.01 and 1.08. The BMI was also associated with FP rates with an OR of 1.03 across all % predicted groups. Assessing the association of age groups with FP rate showed that those above 60 years old were more likely to be categorised as FP with an OR between 1.23 and 73.2 compared to those less than 30 years old. Conclusion: When assessing the small airways in clinical practice or for scientific purposes, the % predicted values overestimate the actual impairment leading to FP interpretation. Utilising z-score values are recommended to assess the small airways using the spirometric index, MMEF. |
| first_indexed | 2024-03-11T15:02:59Z |
| format | Article |
| id | doaj.art-97c2e2af4c784a18acf30fbb524c1131 |
| institution | Directory Open Access Journal |
| issn | 2405-8440 |
| language | English |
| last_indexed | 2024-03-11T15:02:59Z |
| publishDate | 2023-10-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Heliyon |
| spelling | doaj.art-97c2e2af4c784a18acf30fbb524c11312023-10-30T06:07:13ZengElsevierHeliyon2405-84402023-10-01910e20744Small airways dysfunction: The importance of utilising Z-scores to define MMEF abnormalities in clinical practiceMohammed A. Almeshari0Nowaf Y. Alobaidi1Elizabeth Sapey2Robert A. Stockley3James A. Stockley4Rehabilitation Health Sciences Department, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia; Institute of Inflammation and Ageing, University of Birmingham, Edgbaston, Birmingham, UK; Corresponding author. Rehabilitation Health Sciences Department, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia.Respiratory Therapy Department, College of Applied Medical Sciences, King Saud Bin Abdul-Aziz University for Health Sciences, Al Ahsa, Saudi ArabiaInstitute of Inflammation and Ageing, University of Birmingham, Edgbaston, Birmingham, UKDepartment of Lung Function and Sleep, University Hospitals Birmingham NHS Foundation Trust, Edgbaston, Birmingham, B15 2GW, UKDepartment of Lung Function and Sleep, University Hospitals Birmingham NHS Foundation Trust, Edgbaston, Birmingham, B15 2GW, UKBackground: The small airways comprise the largest cross-sectional area of the lungs, however, assessing and reporting abnormalities for this region of the bronchial tree has been practically and scientifically uncertain. Methods: Using routinely collected spirometry data for patients with either asthma or COPD, the accuracy of % predicted values for defining small airways dysfunction was assessed. A z-score of ≤ −1.645 of the maximal-mid expiratory flow (MMEF) was used as the gold standard for defining abnormality in the small airways. Results: Records of 3396 patients were included in the analysis. The false positive (FP) rates were 24.6 %, 16.1 %, 11.5 %, or 7.9 % when the % predicted value of 80 %, 70 %, 65 %, or 60 % were used, respectively. Sex, age, and BMI were associated with FP rates. Males were more likely to be categorised as FP with odds ratio (OR) between 1.10 and 1.49 across % predicted groups. Age was associated with FP rates with an OR between 1.01 and 1.08. The BMI was also associated with FP rates with an OR of 1.03 across all % predicted groups. Assessing the association of age groups with FP rate showed that those above 60 years old were more likely to be categorised as FP with an OR between 1.23 and 73.2 compared to those less than 30 years old. Conclusion: When assessing the small airways in clinical practice or for scientific purposes, the % predicted values overestimate the actual impairment leading to FP interpretation. Utilising z-score values are recommended to assess the small airways using the spirometric index, MMEF.http://www.sciencedirect.com/science/article/pii/S2405844023079525SpirometryZ-scoreStandardised residualSmall airwaysFEF25-75MMEF |
| spellingShingle | Mohammed A. Almeshari Nowaf Y. Alobaidi Elizabeth Sapey Robert A. Stockley James A. Stockley Small airways dysfunction: The importance of utilising Z-scores to define MMEF abnormalities in clinical practice Heliyon Spirometry Z-score Standardised residual Small airways FEF25-75 MMEF |
| title | Small airways dysfunction: The importance of utilising Z-scores to define MMEF abnormalities in clinical practice |
| title_full | Small airways dysfunction: The importance of utilising Z-scores to define MMEF abnormalities in clinical practice |
| title_fullStr | Small airways dysfunction: The importance of utilising Z-scores to define MMEF abnormalities in clinical practice |
| title_full_unstemmed | Small airways dysfunction: The importance of utilising Z-scores to define MMEF abnormalities in clinical practice |
| title_short | Small airways dysfunction: The importance of utilising Z-scores to define MMEF abnormalities in clinical practice |
| title_sort | small airways dysfunction the importance of utilising z scores to define mmef abnormalities in clinical practice |
| topic | Spirometry Z-score Standardised residual Small airways FEF25-75 MMEF |
| url | http://www.sciencedirect.com/science/article/pii/S2405844023079525 |
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