title: Monitoring respiratory muscle strength assists in early diagnosis of respiratory dysfunction as opposed to the isolated use of pulmonary function evaluation in amyotrophic lateral sclerosis.
abstract: OBJECTIVE
  It was study the relationship between respiratory muscle strength and forced vital capacity (FVC) in patients with amyotrophic lateral sclerosis (ALS) versus healthy subjects.
  
  
  METHODS
  Pulmonary function and respiratory muscle strength [maximal inspiratory (PImax), maximal expiratory (PEmax) and sniff nasal inspiratory pressure (SNIP)] were assessed in patients with ALS and healthy subjects, matched using cutoffs established in the literature for impaired pulmonary function and respiratory muscle weakness.
  
  
  RESULTS
  Twenty-eight ALS patients and 28 healthy subjects were studied. We found sensitivity and specificity for PImax, PEmax and SNIP of 75/58%, 81/67% and 75/67%. The Receiver Operating Characteristic curve (ROC curve) indicated that the variables PImax, PEmax and SNIP can identify differences in respiratory muscle strength between ALS and healthy individuals at 0.89, 0.9 and 0.82, respectively. A positive correlation was recorded between FVC (%) versus SNIP, PImax and PEmax.
  
  
  CONCLUSIONS
  In ALS, monitoring respiratory muscle strength assists in early diagnosis of respiratory dysfunction as opposed to the isolated use of FVC.
authors.affiliation: PneumoCardioVascular and Respiratory Muscle Performance, Department of Physical Therapy, Federal University of Rio Grande do Norte (UFRN), Natal RN, Brazil. fregonezi@ufrnet.br
authors.forename: Guilherme
authors.initials: G
authors.lastname: Fregonezi
authors.forename: Palomma Russelly Saldanha
authors.initials: PR
authors.lastname: Araújo
authors.forename: Tathiana Lindemberg Ferreira
authors.initials: TL
authors.lastname: Macêdo
authors.forename: Mario Emilio
authors.initials: ME
authors.lastname: Dourado Junior
authors.forename: Vanessa Regiane
authors.initials: VR
authors.lastname: Resqueti
authors.forename: Armele de Fátima Dornelas de
authors.initials: Ade F
authors.lastname: Andrade
mesh_terms: D000328:Adult; D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000503:physiopathology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D018908:Muscle Weakness / Q000503:physiopathology; D012016:Reference Values; D012119:Respiration; D012120:Respiration Disorders / Q000175:diagnosis* / Q000503:physiopathology; D012132:Respiratory Muscles / Q000503:physiopathology*; D012680:Sensitivity and Specificity; D013997:Time Factors; D014797:Vital Capacity / Q000502:physiology