Background Prior to the onset of overt ventilatory failure, patients with Duchenne Muscular Dystrophy (DMD) can display non-uniform respiratory mechanics, resulting from atelectasis in small lung regions secondary to rapid, shallow breathing and/or peripheral airway obstruction, thereby predisposing to the development of ventilation inhomogeneity.Objectives To investigate ventilation distribution in DMD patients before the initiation of long-term assisted ventilation by using electrical impedance tomography (EIT).Methods Patients and interventions: Eighteen DMD patients underwent EIT between 1 January and 31 December 2025. Primary study endpoint: Global Inhomogeneity Index (GI). EIT data were compared with those obtained from a group of 11 healthy, similarly aged male medical residents.Results GI was significantly higher in the DMD patients with respect to healthy males [0.44 ± 0.13 (0.36–0.77) vs 0.37 ± 0.03 (0.32–0.43); p < 0.001]. A GI of 0.5 maximised the distinction between DMD patients with a ventilation distribution pattern similar to or different from the healthy subjects.Conclusions Before initiation of assisted ventilation, a subset of DMD patients may develop lung ventilation inhomogeneity, which can be readily assessed by means of EIT. Whether such inhomogeneity is predictive of major clinical events therefore constitutes a critical question to be addressed.
Background The six-minute walk test (6MWT) is a simple, widely used measure of functional exercise capacity in children. Standard protocols recommend a 30-meter walking course; however, this is often impractical in routine clinical settings, particularly in resource-limited environments. Normative data for Indian children, especially younger age groups and under pragmatic testing conditions, remain limited.Objectives To establish age- and sex-specific reference values for six-minute walk distance (6MWD) in apparently healthy Indian children aged 4–14 years using a pragmatic 15-meter walking course and evaluate associations with anthropometric variables.Methods In this community-based cross-sectional study, 400 healthy school-going children underwent the 6MWT using a standardized 15-meter indoor course. Anthropometric and baseline physiological parameters were recorded. Percentile reference values were generated, and multivariable linear regression was performed to identify determinants of 6MWD and derive a predictive equation.Results Mean (SD) 6MWD was 365.3 (50.8) meters. Distance increased significantly with age, height, weight, and body mass index (all p<0.001). After adjustment, no independent sex-based differences were observed. The predictive equation was: 6MWD = 279.5 + 8.6 × age (years) + 2.7 × weight (kg) – 5.0 × BMI (kg/m2) (R2 = 0.62). No significant differences were observed by residence or school type.Conclusions This study provides 15-meter course-specific reference values for 6MWD in healthy Indian children aged 4–14 years. The derived predictive equation may assist interpretation of 6MWD obtained using this protocol; however, external validation and direct comparison with the standard 30-meter course are required before broader application, where longer courses are not feasible.
Introduction Treatment-emergent central sleep apnoea (TE-CSA) during positive airway pressure (PAP) therapy is recognised, yet its onset timing and contributing factors remain unclear. This study aimed to ascertain the onset time of TE-CSA via telemonitoring (TM) and identify associated factors.Methods A retrospective cohort of 4,021 obstructive sleep apnoea (OSA) patients treated with PAP and monitored via TM from 2017 to 2022 was analysed. TE-CSA was defined as a residual apnoea-hypopnoea index (AHI) >15 with 50% or more central events. Moreover, if the obstructive apnoea index (OAI) was > 5, patients were excluded. Patients with a central apnoea index (CAI) ≥5 at baseline were excluded. TE-CSA was categorised as transient (<12 weeks), prolonged (12–24 weeks), or persistent (>24 weeks without resolution during the follow-up period). Kaplan–Meier analysis assessed time to TE-CSA onset. A nested case-control study evaluated demographic, cardiovascular, cerebrovascular, sedative use, and PAP treatment type as risk factors.Results TE-CSA occurred in 171 (4.3%, 95% CI: 3.7–4.9) patients, predominantly prolonged (90.6%), with transient (5.9%) and persistent (3.5%) forms. TE-CSA primarily emerged within the first 60 days of PAP therapy. Multivariate analysis identified older age (Odds Ratio (OR) = 1.03, p < 0.001) and male sex (OR = 2.35, p = 0.003) as significant predictors of TE-CSA development.Conclusion Telemonitoring detected that TE-CSA onset was most commonly identified within the first 2 months of PAP therapy. Older age and male sex are key predictors. Early detection through TM could facilitate timely interventions, although therapeutic adjustments were implemented throughout the observation period and may have influenced the temporal patterns observed.
Background Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations in cystic fibrosis transmembrane conductance regulator (CFTR) gene. CFTR modulators are drugs developed to target the defective protein. All over the world, there are patients considered non-eligible for this therapy according to local regulatory policies.Methods To characterise the Portuguese CF patients defined as non-eligible according to genotype for highly effective modulator therapy (HEMT) with elexacaftor/tezacaftor/ivacaftor (ETI), the authors conducted a multicentre observational study based on a retrospective analysis of the Portuguese CF population.Results Based on the current prescribing policy in Portugal, the prevalence of non-eligible patients in Portugal in 2023 was 18.7%, similar to that reported in Europe. However, the regulatory acceleration in the CFTR modulator landscape in 2025 will most likely decrease the expected prevalence to 1.2% under national regulatory adoption of EMA criteria. R334W, G85E, N1303K, G542X, A561E, R1066C and P205S are the most prevalent variants. Most patients are young adults with established pulmonary disease. CF therapies impose a considerable burden on this population.Conclusion This study provides a deeper understanding of the Portuguese CF population currently ineligible for ETI and enables the projection of the potential impact that forthcoming changes in HEMT eligibility criteria may have across Portugal. With the anticipated expansion of these criteria, the number of patients remaining ineligible for HEMT is expected to become residual. Furthermore, the present work offers a characterisation of patients likely to remain ineligible for HEMT in the future, who could be suitable candidates for clinical trials exploring alternative therapeutic approaches.
