Oral steroids for cystic fibrosis.

BACKGROUND

In cystic fibrosis, airway obstruction and recurrent respiratory infection leads to inflammation and eventually long term lung damage, (bronchiectasis), respiratory failure and death. Inflammation occurs early in the disease process, hence the rationale for the use of anti-inflammatory agents such as oral steroids.

OBJECTIVES

To assess the effectiveness of oral steroids in management of respiratory complications cystic fibrosis with particular regard to lung function and occurrence of adverse events. We aimed to to examine short term use for a respiratory exacerbation separately (up to 30 days) from long term anti-inflammatory use (greater than 30 days).

SEARCH STRATEGY

We searched The Cochrane Cystic Fibrosis and Genetic Disorders Group specialist trials register. Date of the most recent search of the Group's specialised register: November 1999.

SELECTION CRITERIA

All randomised or pseudorandomised trials comparing oral corticosteroids given for a period of five to 30 days for treatment of an exacerbation or for more than 30 days used long term, with placebo or no additional therapy in patients with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial eligibility and quality.

MAIN RESULTS

Three trials were identified studying a total of 354 patients. Two of these were long term trials with four year follow up whilst one had follow up to 12 weeks only. There was a lack of data on our predefined outcomes with common outcomes examined at different time-points and also variations in the presentation of common outcomes. A meta-analysis was not possible. Oral corticosteroids at a prednisolone equivalent dose of 1 mg/kg alternate days appear to slow the progression of lung disease in cystic fibrosis. At 24 months from commencement, 70.4% patients treated with 1mg/kg prednisolone on alternate days had an increase in per cent predicted forced vital capacity (FVC) compared to 41.6% patients treated with placebo. The mean absolute change in per cent predicted forced expiratory volume at one second (FEV1) 48 months from commencement was -2% in the 1 mg/kg alternate days prednisolone group but -6% in the placebo group. In the long term, this benefit needs to be weighed against the occurrence of adverse events. Linear growth retardation was observed as early as six months from start of treatment in the 2 mg/kg alternate days prednisolone group and from 24 months of treatment in the 1 mg/kg alternate days prednisolone group. Occurrence of adverse events, particularly glucose abnormalities, cataracts and growth retardation resulted in early termination of one of the four year studies ( approximately approximately Eigen 1995 approximately approximately ), with the group taking 2 mg/kg prednisolone on alternate days being stopped first but followed by the 1 mg/kg alternate days.

REVIEWER'S CONCLUSIONS: Oral corticosteroids at a prednisolone equivalent dose of 1-2 mg/kg alternate days appear to slow the progression of lung disease in CF but this benefit needs to be weighed against the occurrence of adverse events, in particular, development of cataracts and effect on linear growth. A risk/benefit analysis of low-dose alternate days corticosteroids would be important and the role of short term use of oral steroids should be more fully evaluated.