ABSTRACT

Aim: Cystic fibrosis (CF) is an autosomal recessive genetic disorder primarily affecting the lungs and it is a leading cause of morbidity and mortality. Progressive lung disease and acute pulmonary exacerbations (PEx) are significant contributors to poor patient outcomes. Early detection and management of PEx are critical in improving prognosis. Biomarkers have gained interest due to their role in diagnosing, monitoring, and evaluating treatment responses in PEx. This study investigated fluctuations in serum levels of insulin-like growth factor-1 (IGF-1) and its IGF binding protein-3 (IGFBP-3) during CF exacerbations in order to assess their potential as clinical biomarkers.

Materials and Methods: A total of 37 CF patients (16 females, 21 males, mean age 96.95±62.56 months), hospitalized for PEx and receiving intravenous antibiotic treatment, were included. Serum levels of IGF-1 and IGFBP-3 were measured at baseline, at the onset of exacerbation, and at the end of the exacerbation. Additionally, for 16 of the patients, serum levels were reassessed one month post-treatment. Forced expiratory volume (FEV1) measurements were performed for those patients who were able to complete the spirometry test.

Results: At baseline, serum IGF-1 and IGFBP-3 levels were significantly lower than those of the normal population (p<0.001). Marked decreases in IGF-1 and IGFBP-3 levels were observed at the onset of exacerbation compared to the baseline (p<0.05). These levels increased significantly following treatment at the end of the exacerbation (p<0.05), although no significant difference was found between the baseline and posttreatment levels. FEV1 values also showed significant differences between the baseline and exacerbation periods (p<0.05).

Conclusion: Serum levels of IGF-1 and IGFBP-3 in the CF patients were lower than in healthy age-matched controls, with significant fluctuations corresponding to the progression and treatment of acute exacerbations. These fluctuations offer valuable insight into the diagnosis and monitoring of treatment response. Therefore, IGF-1 and IGFBP-3 levels are potentially useful biomarkers for the clinical management of CF exacerbations.