The impact of nocturnal oxygen desaturation on quality of life in cystic fibrosis

Background: Nocturnal oxyhaemoglobin desaturation is common in cystic fibrosis (CF) but the effect on quality of life (QoL) remains unknown. Methods: Sixty stable CF outpatients with mean age 31 +/- 8 years (mean +/- 1SD), BMI 20.8 +/- 3.2 kg/m(2) and FEV1 42 +/- 13% predicted had arterial blood gas sampling, lung function testing, overnight pulse oximetry and completed the CF QoL questionnaire, Epworth Sleepiness Scale and Medical Research Council dyspnoea scale. Results: 11(18%) of the CF patients were 'desaturators,' (SpO(2)< 90% for <= 30% recording time on overnight oximetry). Desaturators had greater difficulty performing their treatments (39 +/- 22 vs 61 +/- 26, p < 0.01) and more exertional dyspnoea (3.2 +/- 0.8 vs 2.0 +/- 0.9, p < 0.001) than non-desaturators after controlling for the effects of FEV1, awake PaO2 and PaCO2 (adjusted p-values < 0.01 and 0.04 respectively). Conclusions: Nocturnal oxyhaemoglobin desaturation is associated with impaired QoL, independent of the effects of lung function and awake gas exchange, in stable CF outpatients with moderate to severe lung disease. (C) 2010 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.