title: 6-Min walk-test data in severe obstructive-sleep-apnea-hypopnea-syndrome (OSAHS) under continuous-positive-airway-pressure (CPAP) treatment.
abstract: BACKGROUND
  Few studies have evaluated the functional capacity of severe OSAHS.
  
  
  OBJECTIVE
  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 (<lower-limit-of-normal), 13% had an oxy-hemoglobin saturation (oxy-sat) fall> 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).
  
  
  CONCLUSIONS
  Severe OSAHS may play a role in reducing the functional capacity.
authors.affiliation: Research Laboratory LR14ES05: Interaction of the Cardiorespiratory System, Faculty of Medicine of Sousse, Sousse, Tunisia; Laboratory of Physiology, Faculty of Medicine, University of Sousse, Tunisia; Department of Physiology and Functional Explorations, Farhat HACHED Hospital, Sousse, Tunisia. Electronic address: helmi.bensaad@rns.tn.
authors.forename: Helmi
authors.initials: H
authors.lastname: Ben Saad
authors.affiliation: Pulmonary Department, Farhat HACHED Hospital, Sousse, Tunisia.
authors.forename: Ikram
authors.initials: I
authors.lastname: Ben Hassen
authors.affiliation: Laboratory of Physiology, Faculty of Medicine, University of Sousse, Tunisia; Department of Physiology and Functional Explorations, Farhat HACHED Hospital, Sousse, Tunisia.
authors.forename: Ines
authors.initials: I
authors.lastname: Ghannouchi
authors.affiliation: Department of Physiology and Functional Explorations, Farhat HACHED Hospital, Sousse, Tunisia.
authors.forename: Imed
authors.initials: I
authors.lastname: Latiri
authors.affiliation: Laboratory of Physiology, Faculty of Medicine, University of Sousse, Tunisia; Department of Physiology and Functional Explorations, Farhat HACHED Hospital, Sousse, Tunisia.
authors.forename: Sonia
authors.initials: S
authors.lastname: Rouatbi
authors.affiliation: Laboratory of Functional Exploration, Hospital Antoine Béclère, Clamart, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Escourrou
authors.affiliation: Pulmonary Department, Farhat HACHED Hospital, Sousse, Tunisia.
authors.forename: Halima
authors.initials: H
authors.lastname: Ben Salem
authors.affiliation: Pulmonary Department, Farhat HACHED Hospital, Sousse, Tunisia.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Benzarti
authors.affiliation: Research Laboratory LR14ES05: Interaction of the Cardiorespiratory System, Faculty of Medicine of Sousse, Sousse, Tunisia; Pulmonary Department, Farhat HACHED Hospital, Sousse, Tunisia.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Abdelghani
mesh_terms: D000328:Adult; D015992:Body Mass Index; D045422:Continuous Positive Airway Pressure / Q000379:methods*; D003430:Cross-Sectional Studies; D005080:Exercise Test / Q000379:methods; D017079:Exercise Tolerance; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010991:Plethysmography / Q000379:methods; D011788:Quality of Life; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology* / Q000628:therapy*; D016138:Walking / Q000502:physiology*
keywords: Deficiency; Impairment; Obstructive-sleep-apnea; Spirometry; Tunisia; Walk-test