title: Subclinical pulmonary dysfunction in spinocerebellar ataxias 1, 2 and 3.
abstract: OBJECTIVE
  Evaluation of pulmonary function in patients with spinocerebellar ataxias (SCA) 1, 2 and 3 without clinical evidence of pulmonary dysfunction.
  
  
  METHODS
  Thirty patients (F:M = 7:23; age: 35 ± 11.3 years; SCA1 - 13, SCA2 - 9 and SCA3 - 8) without clinical manifestations of respiratory dysfunction and 30 controls underwent pulmonary function tests. The percentage predicted values of forced vital capacity (FVC), volume of air exhaled during first second of FVC (FEV1), peak expiratory flow rate (PEFR) and maximal voluntary ventilation (MVV), actual values of maximal inspiratory and expiratory pressures (MIP and MEP in mmHg), and ratios of actual values of FEV1/FVC (%) and FEV1/PEFR (ml/l/min) were analyzed.
  
  
  RESULTS
  Compared with controls SCA patients had significant reductions of FVC (71.1 ± 17.5 vs 85.5 ± 18.7; P < 0.01), PEFR (51.5 ± 20.7 vs 77.1 ± 24.9; P < 0.001), MVV (64.4 ± 21.6 vs 97.2 ± 22.7; P < 0.001), MIP (27.7 ± 16.8 vs 50.1 ± 15.1; P < 0.001) and MEP (38.1 ± 18.7 vs 74.7 ± 16.0; P < 0.001), elevation of FEV1/PEFR (10.5 ± 2.8 vs 7.4 ± 2.1; P < 0.001), but no significant change of FEV1 and FEV1/FVC. FEV1/PEFR correlated positively with illness duration and MVV negatively with severity of illness.
  
  
  CONCLUSIONS
  The present study showed subclinical restrictive type of pulmonary dysfunction in SCA, and possible presence of upper airway obstruction. Chest physiotherapy and breathing exercises should be introduced early in management of SCA.
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neurosciences, Bangalore, India.
authors.forename: S J
authors.initials: SJ
authors.lastname: Sriranjini
authors.forename: P K
authors.initials: PK
authors.lastname: Pal
authors.forename: N
authors.initials: N
authors.lastname: Krishna
authors.forename: T N
authors.initials: TN
authors.lastname: Sathyaprabha
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000209:etiology*; D017827:Machado-Joseph Disease / Q000150:complications*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D020754:Spinocerebellar Ataxias / Q000150:complications*; D013147:Spirometry / Q000379:methods; D013223:Statistics as Topic; D055815:Young Adult