Background: Cystic fibrosis bone disease (CFBD) is a common comorbidity in adult people with cystic fibrosis (pwCF), resulting in an increased risk of bone fractures. This study evaluated the capacity of artificial intelligence (AI)-assisted low-dose chest CT (LDCT) opportunistic screening for detecting low bone mineral density (BMD) in adult pwCF. Methods: In this retrospective single-center study, 65 adult pwCF (mean age 30.1 ± 7.5 years) underwent dual-energy X-ray absorptiometry (DXA) of the lumbar vertebrae L1 to L4 to determine BMD and corresponding z-scores and completed LDCTs of the chest within three months as part of routine clinical care. A fully automated CT-based AI algorithm measured the attenuation values (Hounsfield units [HU]) of the thoracic vertebrae Th9–Th12 and first lumbar vertebra L1. The ability of the algorithm to diagnose CFBD was assessed using receiver operating characteristic (ROC) curves. Results: HU values of Th9 to L1 and DXA-derived BMD and the corresponding z-scores of L1 to L4 showed a strong correlation (all p < 0.05). The area under the curve (AUC) for diagnosing low BMD was highest for L1 (0.796; p = 0.001) and Th11 (0.835; p < 0.001), resulting in a specificity of 84.9% at a sensitivity level of 75%. The HU threshold values for distinguishing normal from low BMD were <197 (L1) and <212 (Th11), respectively. Conclusions: Routine LDCT of the chest with the fully automated AI-guided determination of thoracic and lumbar vertebral attenuation values is a valuable tool for predicting low BMD in adult pwCF, with the best results for Th11 and L1. However, further studies are required to define clear threshold values.

Background: In this study we tested the hypothesis that in patients with cystic fibrosis (pwCF) respiratory rate (RR) is associated with antibiotic treatment, exacerbation status, forced expiratory volume in one second (FEV1) and C-reactive protein (CRP). Methods: Between June 2018 and May 2019, we consecutively enrolled pwCF who were referred to our hospital. We determined RR and heart rate (HR) by using the minimal-impact system VitaLog during the hospital stay. Furthermore, we performed spirometry and evaluated CRP. Results: We included 47 patients: 20 with pulmonary exacerbation and 27 without. RR decreased in patients with exacerbation (27.5/min (6.0/min) vs. 24.4/min (6.0/min), p = 0.004) and in patients with non-exacerbation (22.5/min (5.0/min) vs. 20.9/min (3.5/min), p = 0.024). Patients with exacerbation showed higher RR than patients with non-exacerbation both at the beginning (p = 0.004) and at the end of their hospital stay (p = 0.023). During the hospital stay, HR did not change in the total cohort (66.8/min (11.0/min) vs. 66.6/min (12.0/min), p = 0.440). Furthermore, we did not find significant differences between patients with exacerbation and patients with non-exacerbation (67.0/min (12.5/min) vs. 66.5/min (10.8/min), p = 0.658). We observed a correlation of ρ = -0.36 between RR and FEV1. Moreover, we found a correlation of ρ = 0.52 between RR and CRP. Conclusion: In pwCF requiring intravenous therapy, respiratory rate is higher at their hospital admittance and decreased by the time of discharge; it is also associated with C-reactive protein. Monitoring RR could provide important information about the overall clinical conditions of pwCF.

Background/Objectives: Recent studies indicate that sleep and sleep disorders differ between men and women, but corresponding data in people with chronic lung diseases are lacking. This study aims to answer the question of what the sex-specific differences in sleep profiles and responses to elexacaftor/tezacaftor/ivacaftor (ETI) therapy in people with cystic fibrosis (pwCF) are. Methods: Adult pwCF and a matched control group (adults with suspected sleep-disordered breathing undergoing in-laboratory polysomnography (PSG)) were included. PSG data at baseline and after 6 months’ ETI therapy were compared between men (mwCF) and women (wwCF) with cystic fibrosis. PSG data at baseline and 6-month follow-up for mwCF/wwCF were compared with baseline PSG data for men/women in the control group. Daytime sleepiness was evaluated using the Epworth Sleepiness Scale (ESS). Correlations between change in percentage predicted forced expiratory volume in 1 s from baseline to 6 months were correlated with corresponding changes in key sleep parameters. Changes in transferrin during ETI therapy were also documented. Results: Twenty-eight pwCF (12 wwCF, 16 mwCF) and 28 matched controls were included. Both mwCF (4 ± 5 vs. 9 ± 20 events/h, p = 0.028) and wwCF (3 ± 3 vs. 8 ± 9 events/h, p = 0.004) had fewer respiratory events during sleep versus male and female controls, but worse sleep efficiency (75 ± 11% vs. 84 ± 11%; p = 0.004 and 76 ± 10% vs. 83 ± 11%; p = 0.011. The baseline ESS score was significantly higher in wwCF versus female controls (8 ± 4 vs. 14 ± 8; p = 0.040). Although some sleep parameters normalized during ETI therapy in pwCF, sleep quality remained poor. The transferrin levels at baseline (2.7 ± 0.4 vs. 2.2 ± 0.5; p = 0.049) and 6 months (3.8 ± 0.4 vs. 2.6 ± 0.5; p < 0.001) were significantly higher in the wwCF versus the mwCF, and the change from baseline during ETI therapy was significantly greater in women versus men (1.1 ± 0.6 vs. 0.4 ± 0.4; p < 0.001). Conclusions: These data suggest that wwCF and mwCF should be managed differently with respect to their sleep.

Objective: To assess whether chronic rhinosinusitis (CRS) severity is associated with obstructive sleep apnea (OSA) in adult people with cystic fibrosis (pwCF). Methods: We conducted a retrospective single-center study of 44 adults with CF who underwent overnight polysomnography (PSG), Epworth Sleepiness Scale (ESS) assessment, and sinus computed tomography (CT). CRS severity was quantified using the Lund–Mackay score (LMS) and the main nasal cavity score (MNCS). OSA was defined by Apnea–Hypopnea Index (AHI) thresholds per American Academy of Sleep Medicine criteria. Results: Participants had a mean age of 31.1 ± 8.4 years and a mean percent predicted FEV1 of 51.8 ± 15.7. Sinus CT showed radiological evidence of CRS in all participants. Mean AHI was 5.3 ± 4.4/h; 48% had AHI ≥ 5/h. There were no significant differences between pwCF with and without OSA in age, sex, BMI, lung function, total sleep time, sleep efficiency, or ESS score (all p > 0.05). Mean LMS and MNCS did not differ between OSA and non-OSA groups (both p > 0.05), and neither score correlated with PSG parameters or ESS (all p > 0.05). Receiver operating characteristic (ROC) analysis demonstrated low discriminative ability of LMS and MNCS for predicting OSA (AUCs < 0.70, p < 0.05). Conclusions: In this cohort of adults with CF, CT-based CRS severity was not associated with OSA. Given the substantial prevalence of OSA observed, PSG screening should be considered irrespective of CRS severity.

Background/Objectives: Krebs von den Lungen-6 (KL-6) is a mucin-like glycoprotein that is elevated in a variety of lung diseases and used as a diagnostic and prognostic biomarker in people with cystic fibrosis (pwCF). Single nucleotide polymorphisms (SNPs) in mucin-1 (MUC1) influence KL-6 serum concentration. This study investigated the relationship between serum KL-6 concentrations in pwCF and a MUC1 SNP and its longitudinal dynamics. Methods: The study included pwCF (n = 174) and healthy controls (n = 30). In pwCF, 365 samples were collected for longitudinal analyses; KL-6 levels were measured and the MUC1 SNP rs4072037 was genotyped in pwCF and controls. Cross-sectional and longitudinal associations between KL-6, genotype, and clinical parameters, such as infectious exacerbation, body mass index, inflammatory values and lung function, were analyzed using linear mixed-effects models. Results: Serum KL-6 was significantly elevated in pwCF compared with controls (458 ± 357 vs. 283 ± 103 U/mL; p < 0.001). Homozygous G/G carriers exhibited higher baseline KL-6 than A/A carriers (627 ± 673 vs. 397 ± 148 U/mL; p < 0.001), while heterozygous individuals showed intermediate levels. Longitudinally, the MUC1 SNP and interindividual differences in vital capacity (ppFVC) primarily determined baseline KL-6 levels, explaining 52.5% of variance. Short-term intraindividual fluctuations were largely driven by infectious exacerbations independent of genotype, accounting for ~10% of within-subject variance. Conclusions: PwCF generally showed elevated serum KL-6 levels and reflected both stable interindividual differences, mainly driven by the MUC1 SNP and ppFVC. Dynamic intraindividualchanges were associated with infectious exacerbations. Given the influence of MUC1 polymorphisms (e.g., rs4072037) on KL-6 concentration, personalized interpretation based on the genotype status may be informative in pwCF.