Tracheal section is an independent predictor of asthma in patients with nasal polyposis.

Airway anatomy could be a risk factor for asthma in susceptible patients with airway hyperresponsiveness. This anatomy can be described by only two parameters, the tracheal cross-sectional area and the homothety ratio, which describes the reduction of calibre at each subsequent generation. Thus, we hypothesized that the tracheal area would be linked to the risk of asthma presence. Tracheal area (measured by acoustic reflexion method) and airway responsiveness to metacholine (expressed as Dose Response Slope) were evaluated in 71 consecutive adult patients with nasal polyposis and normal baseline lung function. Hyperresponsiveness was evidenced in 30/71 patients (42%), and 20/71 patients (28%) were asthmatics. Forced expiratory flows were related to tracheal areas (mean value: 3.22±1.32cm(2)). In a logistic multivariate analysis, tracheal area and the degree of responsiveness were independent predictors of asthma. In conclusion, this study suggests that airway anatomy, crudely assessed by tracheal section, is an independent determinant of asthma.

Endurance-training in healthy men is associated with lesser exertional breathlessness that correlates with circulatory-muscular conditioning markers in a cross-sectional design.

Whether exertional dyspnoea can be attributed to poor circulatory-muscular conditioning is a difficult clinical issue. Because criteria of poor conditioning such as low oxygen pulse, low ventilatory threshold or high heart rate/oxygen consumption slope can be observed in heart or lung diseases and are not specific to conditioning, we assessed the relationships between physical exercise, conditioning and exertional breathlessness in healthy subjects, in whom the aforementioned criteria can confidently be interpreted as reflecting conditioning. To this end, healthy males with either low (inactive men, n = 31) or high (endurance-trained men, n = 31) physical activity evaluated using the International Physical Activity Questionnaire (IPAQ) underwent spirometry and incremental exercise testing with breathlessness assessment using Borg scale. No significant breathlessness was reported before the ventilatory threshold in the two groups. Peak breathlessness was highly variable, did not differ between the two groups, was not related to any conditioning criterion, but correlated with peak respiratory rate. Nevertheless, endurance-trained subjects reported lower breathlessness at the same ventilation levels in comparison with inactive subjects. Significant but weak associations were observed between isoventilation breathlessness and physical activity indices (Borg at 60 L/min and total IPAQ scores, rho = -0.31, p = 0.020), which were mainly attributable to the vigorous domain of physical activity, as well as with conditioning indices (Borg score at 60 L.min(-1) and peak oxygen pulse or heart rate/oxygen consumption slope, rho = -0.31, p = 0.021 and rho = 0.31, p = 0.020; respectively). In conclusion, our data support a weak relationship between exertional breathlessness and circulatory-muscular conditioning, the later being primarily related to vigorous physical activity.

Ageing and endurance training effects on quantity and quality of pulmonary vascular bed in healthy men.

It has recently been demonstrated that in healthy individuals, peak oxygen consumption is associated with a greater pulmonary capillary blood volume and a more distensible pulmonary circulation. Our cross-sectional study suggests that, in healthy men aged 20 to 60 years (n = 63), endurance sport practice (vigorous-intensity domain of the International Physical Activity Questionnaire) is associated with better quantity (pulmonary capillary blood volume) and quality (slope of increase in lung diffusion for carbon monoxide on exercise) of the pulmonary vascular bed, partly counterbalancing the deleterious effects of ageing, which remains to be demonstrated in a prospective longitudinal design.

Cross-sectional assessment of the relationships between dyspnea domains and lung function in diffuse parenchymal lung disease.

BACKGROUND: Activity-related dyspnea is the main contributor to the altered quality of life in diffuse parenchymal lung diseases (DPLD). Instruments pertaining to dyspnea are classified as pertaining to domains of sensory-perceptual experience, affective distress or symptom/disease impact; whether these domains are equally related to lung function impairments remains to be established. OBJECTIVES: They were to assess the relationships between two domains of dyspnea (sensory-perceptual experience and symptom impact) and pulmonary function tests according to their evaluation of ventilatory demand, capacity and drive in patients suffering from DPLD. METHODS: Fifty patients were prospectively enrolled (median age, 58 years; 25 women) and underwent spirometry, body plethysmography, measurements of lung diffusion for carbon monoxide (DLCO) and nitric oxide, maximal airway pressures (capacity and demand assessments), mouth occlusion pressure at 0.1 s (P0.1: respiratory drive assessment) and a 6-min walk test with Borg score assessment (dyspnea: sensory domain). The impact domain of dyspnea was evaluated using the baseline dyspnea index. RESULTS: The sensory domain of dyspnea was linked to demand (CO transfer coefficient, kCO) only, while the impact domain was independently linked to demand and capacity (kCO and forced vital capacity, respectively). Among resting pulmonary function tests, both P0.1 and DLCO allowed the assessment of these two domains of dyspnea. CONCLUSIONS: In DPLD, the sensory-perceptual domain of dyspnea is mainly linked to alterations in ventilatory demand while the impact domain is related to both demand and capacity. DLCO that assesses both demand and capacity and P0.1 were the strongest correlates of dyspnea.