title: Relationship between sniff nasal inspiratory pressure and BODE index in patients with COPD.
abstract: OBJECTIVE
  The aims of this study were to investigate the relationship between sniff nasal inspiratory pressure (SNIP) and severity of chronic obstructive pulmonary disease (COPD) as defined by the BODE index, and to investigate the capacity of different SNIP cutoffs to predict a BODE index score ≥5 (i.e., worse disease severity).
  
  
  METHODS
  Thirty-eight subjects with COPD (21 men, 66 ± 8 years, forced expiratory volume in the first second (FEV(1)) 42 ± 16 % predicted) underwent assessments of SNIP, airflow limitation, body mass index (BMI), dyspnea (Medical Research Council scale), and exercise capacity (6-min walking test, 6MWT). The BODE index was calculated, and patients were separated into two groups according to the BODE quartiles (1 and 2, or 3 and 4).
  
  
  RESULTS
  Patients from quartiles 3 and 4 presented lower values of SNIP than patients from quartiles 1 and 2 (73 ± 18 vs 56 ± 21 cmH(2)O, respectively; p = 0.01). There was significant and inverse correlation between SNIP and the BODE index (r = -0.62; p<0.001). A logistic regression model revealed that a SNIP value below 63 cmH(2)O presented higher sensitivity and specificity (70 and 67 %, respectively) for predicting a BODE score equivalent to quartiles 3 or 4.
  
  
  CONCLUSIONS
  SNIP is moderately and significantly related to COPD severity as assessed by the BODE index. Moreover, the cutoff point of 63 cmH2O showed the best combination of sensitivity and specificity for predicting worse scores in the BODE index.
authors.affiliation: Laboratório de Pesquisa em Fisioterapia Pulmonar (LFIP), Departamento de Fisioterapia, Universidade Estadual de Londrina (UEL), Avenida Robert Koch, 60 - Vila Operária, 86038-350, Londrina, PR, Brazil.
authors.forename: Leila
authors.initials: L
authors.lastname: Donária
authors.forename: Rafael
authors.initials: R
authors.lastname: Mesquita
authors.forename: Larissa
authors.initials: L
authors.lastname: Martinez
authors.forename: Luciana
authors.initials: L
authors.lastname: Sípoli
authors.forename: Josiane Marques
authors.initials: JM
authors.lastname: Felcar
authors.forename: Vanessa Suziane
authors.initials: VS
authors.lastname: Probst
authors.forename: Nidia Aparecida
authors.initials: NA
authors.lastname: Hernandes
authors.forename: Fabio
authors.initials: F
authors.lastname: Pitta
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D015992:Body Mass Index; D001938:Brazil; D003430:Cross-Sectional Studies; D005069:Evaluation Studies as Topic; D005080:Exercise Test / Q000379:methods; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D001239:Inhalation / Q000502:physiology; D007320:Inspiratory Capacity / Q000502:physiology; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology; D009296:Nasal Cavity / Q000503:physiopathology*; D011237:Predictive Value of Tests; D011312:Pressure; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000401:mortality* / Q000503:physiopathology; D012132:Respiratory Muscles / Q000503:physiopathology*; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D015996:Survival Rate