Background: The lung disease in cystic fibrosis is characterised by impaired mucociliary clearance. Hypertonic saline (HS) has been shown to enhance mucociliary clearance in-vitro and this may act to lessen the destructive inflammatory process in the airways.
Objectives: To investigate the effects of treatment with nebulised hypertonic saline on people with CF compared to placebo and or other treatments that enhance mucociliary clearance.
Search strategy: 'We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group trials register which comprises references identified from comprehensive electronic database searches, handsearching relevant journals and handsearching abstract books of conference proceedings. Date of the most recent search of the Group's register: October 2001.
Selection criteria: All controlled trials (any language) assessing the effect of hypertonic saline compared to placebo or other mucolytic therapy, for any duration or dose regimen in people with cystic fibrosis of any age or severity.
Data collection and analysis: All identified trials were independently reviewed by both reviewers & all data collected. Trial quality was assessed along with allocation concealment.
Main results: Fourteen controlled trials were identified. Nine trials met the inclusion criteria; these involved 235 participants with an age range of 6 to 46 years. Two short-term trials of immediate effect on mucociliary clearance demonstrated that HS increased isotope clearance compared to control. Lung function as measured by improvement in Forced Expiratory Volume at one second (FEV1 l/min) was observed in four trials. When 3% to 7% saline was used in a volume of 10mls twice a day, in comparison to placebo, HS led to a significant increase in FEV1, WMD 12.20 (95%CI 4.30 to 20.10). In comparison to deoxyribonuclease (DNase) two trials used a similar concentration and volume of HS. Over a three week period the groups showed a similar increase in FEV1, WMD -1.60 (95%CI -11.16 to 7.96). However after 12 weeks treatment in participants with moderate to severe lung disease compared to DNase, HS 5mls twice a day showed less benefit to FEV1, WMD -13.00 (95%CI -22.46 to -3.54). No serious adverse events were noted.
Reviewer's conclusions: Nebulised hypertonic saline improves mucociliary clearance in short term clinical trials and appears to increase lung function compared to control. In comparison to DNase it may be less effective at improving lung function, after three months. At this stage there is insufficient evidence to support the use of hypertonic saline as routine treatment for people with cystic fibrosis.