We read with interest the review of JANSSENS et al. [1] entitled "Physiological changes in respiratory function associated with ageing", more specifically the subheading devoted to changes in arterial oxygenation and ventilation-perfusion (V ©/Q ©) relationships. Although the seminal study of WAGNER et al.[2] was addressed in full, it was a shame that they did not discuss the more recent comprehensive work of our group in this field [3]. We extensively investigated the distributions of V ©/Q © ratios in 64 healthy individuals aged 18±71 yrs. The principal findings of that study were: 1) that V ©/Q © imbalance, but not increased intrapulmonary shunting, did increase with age as previously expected; 2) that the increase over the span of~50 yrs was physiologically very small; 3) that most of the variance in V ©/Q © mismatch in this cohort of subjects was not due to ageing and remained unsettled; and 4) that the fall in arterial partial pressure of oxygen (PO 2 ) with age was also quite small but was internally consistent with the V ©/Q © changes measured independently.V ©/Q © relationships were characterized in most of these healthy individuals by narrow distributions that widened slightly with age together with a trivial shunt of <1% of the cardiac output in 90% of cases. Both the second moments (dispersions) of pulmonary blood flow (Log SDQ) and of alveolar ventilation (Log SDV) increased by~0.1 between 20±70 yrs. Accordingly, the dispersion of pulmonary perfusion (Log SDQ) increased from 0.36±0.47, akin to a decrease of oxygen tension in arterial blood (Pa,O 2 ) of only~6 mmHg. Only 10% of the total variance was attributed to age. A similar amount was due to intrasubject variability, but none was due to variations in other factors, such as forced expiratory volume in one second (FEV1), FEV1/forced vital capacity (FVC) ratio, weight or height. We did not measure closing volume and it is therefore likely that age could disturb V ©/Q © matching as a result of increases in closing volume. However, since the latter mechanism is highly unlikely to influence V ©/ Q © relationships in young healthy individuals [4], and since the variance of the dispersion of pulmonary blood flow was as large amongst the subset of young as that of old individuals, we would postulate that increased closing volume is not a determinant factor of the variance in V ©/Q © homogeneity.

Non-invasive ventilation (NIV) is recognised as an effective treatment for chronic hypercapnic respiratory failure. Monitoring NIV during sleep may be preferable to daytime assessment. This paper reports the findings of an international consensus group which systematically analysed nocturnal polygraphic or polysomnographic tracings recorded with either volume-cycled or pressure-cycled ventilators. A systematic description of nocturnal respiratory events which occur during NIV is proposed: leaks, obstruction at different levels of the upper airway (glottis and/or pharynx), with or without decrease of respiratory drive and asynchrony

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In subjects with normal lung mechanics, inspiratory muscle strength can be reliably and easily assessed by the sniff nasal inspiratory pressure (SNIP), which is the pressure measured in an occluded nostril during a maximal sniff performed through the contralateral nostril. The aim of this study was to assess the validity of the SNIP in patients with chronic obstructive pulmonary disease (COPD), where pressure transmission from alveoli to upper airways is likely to be dampened.Twenty eight patients with COPD were studied (mean forced expiratory volume in one second (FEV1) = 36% of predicted). The SNIP and the sniff oesophageal pressure (sniff Poes) were measured simultaneously during maximal sniffs, and were compared to the maximal inspiratory pressure obtained against an occlusion (MIP). All measurements were performed from functional residual capacity in the sitting position.The ratio SNIP/sniff Poes was 0.80, and did not correlate with the degree of airflow limitation. The ratio MIP/sniff Poes was 0.87, and the ratio SNIP/MIP was 0.97. Inspiratory muscle weakness, as defined by a low sniff Poes, was present in 17 of the 28 patients. A false diagnosis of weakness was made in eight patients when MIP was considered alone, in four when SNIP was considered alone, and in only three patients when MIP and SNIP were combined.We conclude that both the sniff nasal inspiratory pressure and the maximal inspiratory pressure moderately underestimate sniff oesophageal pressure in chronic obstructive pulmonary disease. Although suboptimal in this condition, the sniff nasal inspiratory pressure appears useful to complement the maximal inspiratory pressure for assessing inspiratory muscle strength in patients with chronic obstructive pulmonary disease.

Background More advanced knowledge is needed on how COPD alters the clinical presentation of obstructive sleep apnea (OSA) and how the association of both diseases, known as 'overlap syndrome' (OVS), impacts on cardiovascular health. Objective To investigate differences between patients with OVS and those with moderate-to-severe OSA alone. Methods A cross-sectional study conducted in the French National Sleep Apnea Registry between January 1997 and January 2017. Univariable and multivariable logistic regression models were used to compare OVS versus OSA alone on symptoms and cardiovascular health. Results 46,786 patients had moderate-to-severe OSA. Valid spirometry was available for 16,466 patients: 14,368 (87%) had moderate-to-severe OSA alone and 2098 (13%) had OVS. A lower proportion of OVS patients complained of snoring, morning headaches and excessive daytime sleepiness compared to OSA alone (median Epworth Sleepiness Scale score: 9 [interquartile range (IQR) 6-13] versus 10 (IQR 6-13), respectively; P <0.02). Similarly, a lower proportion of OVS patients (35.6% versus 39.4%, respectively; P <0.01) experienced sleepiness while driving. In contrast, 63.5% of the OVS population experienced nocturia compared to 58.0% of the OSA population (P<0.01). Apnea hypopnea index (36 [25; 52] vs 33.1 [23.3; 50]), oxygen desaturation index (28 [15; 48] vs 25.2 [14; 45]) and mean nocturnal

More than 10 years after publication, international guidelines remain poorly implemented. To better implement them, we need to develop new strategies adapted to the expectations of patients and health professionals outside hospital settings and to ensure better outpatient follow up in the community. We developed a bilingual education programme including a brochure designed to support an interdisciplinary health care network and measured hospitalisations (H), work absenteeism (WA), emergency visits (EV), asthma medication (AM) and quality of life (QL Juniper) before and 12 months after the intervention. All QL scores improved significantly in comparison with pre-intervention values. Health service use decreased dramatically when comparing the 12 months prior to and after the intervention(H: 35-8%, WA: 39-14%, EV: 88-53%). The final cost/benefit ratio of the programme was 1.96. Interdisciplinary implementation strategy of patient education is cost-effective, improves quality of life for asthmatics, and reduces strain on health services. Such a health care network does not require an expensive infrastructure and is better adapted to the reality and competences of clinical practice.

Anatomo-pathological evidence of CB or E is highly prevalent in older patients, suggesting that CB and E are clinically underdiagnosed in this age group. Fatal MI occurred significantly more frequently in older patients with E or CB than in controls. Furthermore, patients with E were at significantly higher risk of fatal PE than patients with CB or controls.

Background: Evaluation of health-related quality of life (HRQL) in chronic respiratory failure (CRF) is an important issue for evaluating the impact of treatment. Objectives: To elaborate a French version of the Maugeri Foundation Respiratory Failure Questionnaire (MRF-28) disease-specific HRQL questionnaire and determine its validity and reliability in patients with CRF treated by home mechanical ventilation (HMV). Methods: Forward- and back-translation of the MRF-28 questionnaire; the final version was submitted to 81 patients treated with HMV for CRF, simultaneously with the St. George’s Respiratory Questionnaire (SGRQ), the Short Form 36 (SF-36), and the Hospital Anxiety and Depression scale (HAD). Validity was determined by correlation with previously validated HRQL scores and recorded physiological parameters. Reliability was evaluated by assessing internal consistency and test-retest stability of the MRF-28 scores. Results: The French version of the MRF-28 and its subscores (‘daily activity’, ‘cognitive function’, and ‘invalidity’) were highly significantly correlated with subscores of the SGRQ, the SF-36 and the HAD. Both the MRF-28 and the SGRQ were correlated only with age and the 6-min walk test. The MRF-28 showed high test-retest reliability after 2 weeks (r² = 0.80, p < 0.0001) and high internal consistency (Crohnbachs’ α coefficient: 0.91). Conclusion: The French version of the MRF-28 is a valid and reliable disease-specific questionnaire for assessing HRQL in patients with CRF.