Dose-response relationship of inhaled corticosteroids and cataracts: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE The risk of cataracts associated with the long-term use of inhaled corticosteroids (ICS) is poorly recognized, yet may be of major public health importance. The aim of this study was to determine the dose-response relationship of ICS use and risk of cataracts in adults. METHODS A systematic review and meta-analysis was performed of case-control studies of cataracts and ICS use, which included at least two doses of ICS and in which the number of cases and controls using each dose of ICS was reported. The primary outcome variable was risk of cataracts. RESULTS Four case-control studies were identified, with a total of 46 638 cases and 146 378 controls. There was a significant relationship between the risk of cataracts and ICS dose, with a random effects pooled odds ratio for risk of cataracts per 1000 microg increase in daily beclomethasone dipropionate dose of 1.25 (95% CI: 1.14-1.37). CONCLUSIONS The risk of cataracts was increased by approximately 25% for each 1000 microg per day increase in the dose of beclomethasone dipropionate or equivalent. These findings reinforce the importance of prescribing within the therapeutic dose-response range for ICS in asthma and the need to determine the dose-response relationship for the efficacy of ICS in COPD. Screening for the presence of cataracts could usefully be undertaken in older subjects with asthma and COPD, particularly current or ex-smokers.