A prelude for better understanding and conclusive diagnosis of asthma: a study using pulmonary function test in conjugation with other biomarkers

Abstract

ABSTRACT Asthma remains an increasing cause of morbidity and mortality in adults, especially in developing nations. In Libya, no previous study has reported the diagnosis of asthma among adults. The primary objective of this work is to validate the diagnosis of asthma through a survey questionnaire for adult Libyans, by using a digital spirometer as a recommendation to diagnose asthma. The specific objective of this study included the search for a correlation between asthma symptoms and its diagnosis. The Study run at two stages, using spirometer for validation and detecting of asthma biomarkers as follow: Methods: A. An adapted International Study of Asthma and Allergies in Childhood questionnaire was distributed to 1800 subjects > 18 years. B. A prospective, longitudinal study was conducted with a cohort of adult patients with severe asthma who required daily treatment with inhaled corticosteroids. Patients underwent lung function testing using spirometry, sputum samples were taken for inflammatory cell count and sputum supernatant and exhaled respiration were taken for Fractional exhaled nitric oxide, FeNOmeasurement. Forced expiratory volume levels were measured, along withIgE, eosinophil count, asthma-specific health-related quality of life, asthma-exact signs scores, and time to treatment failure. These indicators were measured over the 22-week study period. Results: A. Females comprised 56.7% of the sample. Pulmonary function tests (spirometry) were performed on respondents who reported wheezing and chest tightness at rest and during daily activity. Approximately 17.6% of the participants reported having wheezes during the last 12 months, while 18.4% had chest tightness at rest and during daily activities. A significant correlation was found between wheezing and chest tightness (p<0.001). About 44% of the participants showed a positive reversibility test. B. A total of 1800 participants were recruited, 56.7% were female and 70% of the participants were aged 18-27 years. FeNO was valuable prognostic biomarker for asthma exacerbations, along with FEV1 reduction. A greater quantity of eosinophils was correlated with a reduced risk of exacerbation in females, with no correlation in males. Elevated serum IgE levels were correlated with an increased risk of lung fibrosis. We found no significant relationships between the investigated indicators and hospitalization. Conclusion: Chest tightness at rest and wheezing are more reliable for diagnosing asthma. The city of Sirte in Libya requires the establishment of the common pollens which trigger asthma. FeNO, in conjunction with other biomarkers, is a useful prognostic indicator of exacerbations of symptoms in asthma patients.