Dataset Information

Combined forced oscillation and fractional-order modeling in patients with work-related asthma: a case-control study analyzing respiratory biomechanics and diagnostic accuracy.

ABSTRACT:

Background

Fractional-order (FrOr) models have a high potential to improve pulmonary science. These models could be useful for biomechanical studies and diagnostic purposes, offering accurate models with an improved ability to describe nature. This paper evaluates the performance of the Forced Oscillation (FO) associated with integer (InOr) and FrOr models in the analysis of respiratory alterations in work-related asthma (WRA).

Methods

Sixty-two individuals were evaluated: 31 healthy and 31 with WRA with mild obstruction. Patients were analyzed pre- and post-bronchodilation. The diagnostic accuracy was evaluated using the area under the receiver operating characteristic curve (AUC). To evaluate how well do the studied models correspond to observed data, we analyzed the mean square root of the sum (MSEt) and the relative distance (R_d) of the estimated model values to the measured resistance and reactance measured values.

Results and discussion

Initially, the use of InOr and FrOr models increased our understanding of the WRA physiopathology, showing increased peripheral resistance, damping, and hysteresivity. The FrOr model (AUC?=?0.970) outperformed standard FO (AUC?=?0.929), as well as InOr modeling (AUC?=?0.838) in the diagnosis of respiratory changes, achieving high accuracy. FrOr improved the curve fitting (MSEt?=?0.156?±?0.340; R_d?=?3.026?±?1.072) in comparison with the InOr model (MSEt?=?0.367?±?0.991; R_d?=?3.363?±?1.098). Finally, we demonstrated that bronchodilator use increased dynamic compliance, as well as reduced damping and peripheral resistance.

Conclusions

Taken together, these results show clear evidence of the utility of FO associated with fractional-order modeling in patients with WRA, improving our knowledge of the biomechanical abnormalities and the diagnostic accuracy in this disease.

SUBMITTER: Tuza FADA

PROVIDER: S-EPMC7724713 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Publications

Combined forced oscillation and fractional-order modeling in patients with work-related asthma: a case-control study analyzing respiratory biomechanics and diagnostic accuracy.

Tuza Fábio Augusto D Alegria FADA de Sá Paula Morisco PM Castro Hermano A HA Lopes Agnaldo José AJ de Melo Pedro Lopes PL

Biomedical engineering online 20201209 1

<h4>Background</h4>Fractional-order (FrOr) models have a high potential to improve pulmonary science. These models could be useful for biomechanical studies and diagnostic purposes, offering accurate models with an improved ability to describe nature. This paper evaluates the performance of the Forced Oscillation (FO) associated with integer (InOr) and FrOr models in the analysis of respiratory alterations in work-related asthma (WRA).<h4>Methods</h4>Sixty-two individuals were evaluated: 31 heal ...[more]

PMID: 33298072

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Project description:IntroductionPerforming lung function test in geriatric patients has never been an easy task. With well-established evidence indicating impaired small airway function and air trapping in patients with geriatric COPD, utilizing forced oscillation technique (FOT) as a supplementary tool may aid in the assessment of lung function in this population.AimsTo study the use of FOT in the assessment of airflow limitation and air trapping in geriatric COPD patients.Study designA cross-sectional study in a public hospital in Hong Kong. ClinicalTrials.gov ID: NCT01553812.MethodsGeriatric patients who had spirometry-diagnosed COPD were recruited, with both FOT and plethysmography performed. "Resistance" and "reactance" FOT parameters were compared to plethysmography for the assessment of air trapping and airflow limitation.ResultsIn total, 158 COPD subjects with a mean age of 71.9±0.7 years and percentage of forced expiratory volume in 1 second of 53.4±1.7 L were recruited. FOT values had a good correlation (r=0.4-0.7) to spirometric data. In general, X values (reactance) were better than R values (resistance), showing a higher correlation with spirometric data in airflow limitation (r=0.07-0.49 vs 0.61-0.67), small airway (r=0.05-0.48 vs 0.56-0.65), and lung volume (r=0.12-0.29 vs 0.43-0.49). In addition, resonance frequency (Fres) and frequency dependence (FDep) could well identify the severe type (percentage of forced expiratory volume in 1 second <50%) of COPD with high sensitivity (0.76, 0.71) and specificity (0.72, 0.64) (area under the curve: 0.8 and 0.77, respectively). Moreover, X values could stratify different severities of air trapping, while R values could not.ConclusionFOT may act as a simple and accurate tool in the assessment of severity of airflow limitation, small and central airway function, and air trapping in patients with geriatric COPD who have difficulties performing conventional lung function test. Moreover, reactance parameters were better than resistance parameters in correlation with air trapping.

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Dataset Information

Combined forced oscillation and fractional-order modeling in patients with work-related asthma: a case-control study analyzing respiratory biomechanics and diagnostic accuracy.

Background

Methods

Results and discussion

Conclusions

Publications

Combined forced oscillation and fractional-order modeling in patients with work-related asthma: a case-control study analyzing respiratory biomechanics and diagnostic accuracy.

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