title: Reference values for sniff nasal inspiratory pressure in healthy subjects in Brazil: a multicenter study.
abstract: OBJECTIVE
  The objectives of this study were to determine reference values for sniff nasal inspiratory pressure (SNIP) and to propose reference equations for the population of Brazil.
  
  
  METHODS
  We evaluated 243 healthy individuals (111 males and 132 females), between 20 and 80 years of age, with an FVC and FEV1/FVC ratio > 80% and > 85% of the predicted value, respectively. All of the subjects underwent respiratory muscle strength tests to determine MIP, MEP, and SNIP.
  
  
  RESULTS
  We found that SNIP values were higher in males than in females (p < 0.05) and that SNIP correlated negatively with age, for males (r = -0.29; p < 0.001) and for females (r = -0.33; p < 0.0001). Linear regression also revealed that age influenced the predicted SNIP, for males (R² = 0.09) and females (R² = 0.10). We obtained predicted SNIP values that were higher than those obtained for other populations.
  
  
  CONCLUSIONS
  We have devised predictive equations for SNIP to be used in adults (20-80 years of age) in Brazil. These equations could help minimize diagnostic discrepancies among individuals.
authors.affiliation: Rede Nordeste de Biotecnologia – RENORBIO, Northeastern Biotechnology Network – Natal, Brazil.
authors.forename: Palomma Russelly Saldanha
authors.initials: PR
authors.lastname: Araújo
authors.forename: Vanessa Regiane
authors.initials: VR
authors.lastname: Resqueti
authors.forename: Jasiel
authors.initials: J
authors.lastname: Nascimento Junior
authors.forename: Larissa de Andrade
authors.initials: Lde A
authors.lastname: Carvalho
authors.forename: Ana Gabriela Leal
authors.initials: AG
authors.lastname: Cavalcanti
authors.forename: Viviane Cerezer
authors.initials: VC
authors.lastname: Silva
authors.forename: Ester
authors.initials: E
authors.lastname: Silva
authors.forename: Marlene Aparecida
authors.initials: MA
authors.lastname: Moreno
authors.forename: Arméle de Fátima Dornelas de
authors.initials: Ade F
authors.lastname: Andrade
authors.forename: Guilherme Augusto de Freitas
authors.initials: GA
authors.lastname: Fregonezi
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D001239:Inhalation / Q000502:physiology*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D011237:Predictive Value of Tests; D011312:Pressure; D012016:Reference Values; D012132:Respiratory Muscles / Q000502:physiology*; D013147:Spirometry; D055815:Young Adult