Ines Ghannouchi

Investigation of Exclusive Narghile Smokers: Deficiency and Incapacity Measured by Spirometry and 6-Minute Walk Test

BACKGROUND: Studies on the submaximal aerobic capacity of exclusive narghile smokers (ENS) seem necessary in view of effective prevention of cardiorespiratory diseases. The goal of the study was to assess, by 6-min walk test (6MWT) data, the submaximal aerobic capacity of ENS, to identify factors influencing their 6-min walk distance (6MWD), and to compare their data with those of a healthy non-smoker (HNS) group. METHODS: Seventy 20–60-y-old male ENS were included. Narghile use (narghile-years) and anthropometric, clinical, spirometric, and 6MWT data were collected. Univariate and multivariate analyses were used to identify factors influencing 6MWD. Data of a subgroup of 40–60-y-old ENS (n = 25) were compared with those of an age-matched HNS group (n = 53). RESULTS: The median (first to third quartile) for age and narghile use were 32 (26–43) and 17 (8–32) narghile-years, respectively. The profile of ENS performing the 6MWT was as follows: at the end of the 6MWT, 34% and 9% had a low heart rate (< 60% of maximum predicted) and high dyspnea scores (> 5/10, visual analog scale), respectively; 3% had an oxyhemoglobin saturation decrease of > 5 points during the test; and 20% had an abnormal 6MWD (less than the lower limit of the normal range). The factors that significantly influenced the 6MWD, explaining 38% of its variability, are included in the following equation: 6MWD (m) = 742.63 − 5.20 × body mass index (kg/m2) + 25.23 × FEV1 (L) − 0.44 × narghile use (narghile-years). Compared with HNS, the subgroup of ENS had a significantly lower 6MWD (98 ± 7 vs 87 ± 9% predicted, respectively). CONCLUSIONS: Narghile use may play a role in reducing submaximal aerobic capacity. The present study suggests that a program of pulmonary rehabilitation is an excellent axis to follow.

Exploration de la déficience et de l’incapacité des patients atteints d’un syndrome d’apnées hypopnées obstructives du sommeil

BACKGROUND In addition to excessive daytime somnolence, exercise limitation is a likely consequence of the cardiorespiratory problems that occur in patients who have obstructive sleep apnoea (OSA). However, few studies have evaluated the aerobic capacity of this patient group. AIMS To evaluate submaximal exercise capacity over the 6-minute walking test (6-MWT). To determine the factors that influence 6-minutes walking distance (6-MWD). METHODS INCLUSION CRITERIA 120 consecutive patients with severe OSA treated by continuous positive airway pressure who were medically stable will be included. EXCLUSION CRITERIA 6-MWT contraindications, orthopaedic or rheumatologic diseases likely to influence walking capacity and corticosteroid therapy. INVESTIGATIONS polysomnography, electrocardiogram, plethysmography, and two 6-MWTs. Indicators of impaired exercise capacity: stops during the walk, 6-MWD less than or equal to predicted lower limit of normal, end walking dyspnoea greater than or equal to 5/10, oxygen saturation fall greater than or equal to five points, end walking heart rate less than or equal to 60 % maximal predicted. Data from our obese patients aged 40-60 years old will be compared with data from 45 age-matched obese subjects free from OSA. EXPECTED RESULTS OSA will significantly affect the submaximal exercise capacity and will accelerate the ageing of the cardiorespiratory-muscle chain. Submaximal exercise capacity of obese subjects having OSA, compared to subjects free from OSA, will be significantly deteriorated. 6-MWD of OSA patients will be significantly influenced by: resting plethysmographic data, apnoea hypopnoea index, arterial hypertension, obesity or smoking histories.

6-Min walk-test data in severe obstructive-sleep-apnea-hypopnea-syndrome (OSAHS) under continuous-positive-airway-pressure (CPAP) treatment.

INTRODUCTION Few studies have evaluated the functional capacity of severe OSAHS. AIMS To assess their functional capacity, identify their 6-min walking-distance (6MWD) influencing factors and compare their data with those of two control-groups. METHODS Sixty (42 males) clinically consecutive stable patients with severe OSAHS under CPAP were included. Clinical, Epworth questionnaire, anthropometric, polysomnographic, plethysmographic and 6-min walk-test (6MWT) data were collected. Univariate and multivariate analyses were used to identify the 6MWD influencing factors. Data of a subgroup of severe OSAHS aged ≥40 Yrs (n = 49) were compared with those of non-obese (n = 174) and obese (n = 55) groups. RESULTS The means ± SD of age and apnea-hypopnea-index were, respectively, 49 ± 10 Yr and 62 ± 18/h. The profile of OSAHS patients carrying the 6MWT, was as follows: at the end of the 6MWT, 31% and 25% had, respectively, a high dyspnea (>5/10, visual analogue scale) and a low heart-rate (<60% of-maximal-predicted), 13% had an abnormal 6MWD ( 5 points and 3% stopped the walk. The factors that significantly influenced the 6MWD, explaining 80% of its variability, are included in the following equation: 6MWD (m) = 29.66 × first-second-forced-expiratory-volume (L) - 4.19 × Body-mass-index (kg/m(2)) - 51.89 × arterial-hypertension (0. No; 1. Yes) + 263.53 × Height (m) + 2.63 × average oxy-sat during sleep (%) - 51.06 × Diuretic-use (0. No; 1. Yes) - 20.68 × Dyspnea (NYHA) (0. No; 1. Yes) - 38.09 × Anemia (0. No; 1. Yes) + 5.79 × Resting oxy-sat (%) - 586.25. Compared with non-obese and obese groups, the subgroup of OSAHS has a significantly lower 6MWD [100 ± 9%, 100 ± 8% and 83 ± 12%, respectively). CONCLUSION Severe OSAHS may play a role in reducing the functional capacity.

Defining and grading an obstructive ventilatory defect (OVD): ‘FEV1/FVC lower limit of normal (LLN) vs. Z-score’ and ‘FEV1 percentage predicted (%pred) vs. Z-score’

ABSTRACT An obstructive ventilatory defect (OVD) is defined by a low forced expiratory volume/‘forced/slow’ vital capacity (FEV1/FVC) (e.g. <lower limit of normal (LLN)). However, the LLN can be estimated either by the 90% confidence interval (or the 90th percentile) (American Thoracic and the European Respiratory Societies (ATS/ERS) method) or by the Z-score (global lung initiative (GLI) method). In 2014, a new alternative classification (GLI classification) for grading the OVD severity was proposed to replace the 2005-ATS/ERS one. The aims of the present study were to determine, according to the two methods (GLI vs. ATS/ERS), the frequency of participants having an OVD; and to compare the two classifications (GLI vs. ATS/ERS) of OVD severity. This was a prospective study including 1000 participants (mean age = 41 ± 10 years). The OVD was defined according to the ATS/ERS [FEV1/FVC < LLN (=local norms value − 1.64 × residual standard deviation)] and GLI (FEV1/FVC Z-score < −1.64) criteria. The following OVD classifications severity were applied: ATS/ERS (FEV1%pred): mild (>70%), moderate (60–69%), moderately severe (50–59%), severe (35–49%), and very severe (<35%) and GLI (FEV1 Z-score): mild (≥ −2.0), moderate (−2.0 to −2.5), moderately severe (−2.5 to −3.0), severe (−3.0 to −4.0), and very severe (<−4.0). The frequencies of OVD were 14.4% (ATS/ERS method) and 10.5% (GLI method) (p < 0.05). Among the 103 participants having an OVD according to the two methods, the severity classification was mild (34.95% vs. 37.86%, p < 0.05), moderate (25.24% vs. 18.45%, p < 0.05), moderately severe (23.30% vs. 15.53%, p = 0.144), severe (9.71% vs. 20.39%, p < 0.05), and very severe (6.80% vs. 7.77%, p = 0.785), respectively for the ATS/ERS and GLI classifications. The two OVD definitions were not exchangeable. Moreover, the two grading severity systems misclassified the OVD grades.