Double-blinded randomised controlled trials (RCTs) of at least six months' duration, comparing budesonide or budesonide and formoterol with placebo or formoterol alone, in patients with chronic obstructive pulmonary disorder, were eligible for inclusion. Chronic obstructive pulmonary disorder had to be defined either by clinical diagnosis or as current or former smoker (10 pack-year smoking history or over) with a forced expiratory volume (in one second) (FEV1) to forced vital capacity ratio of less than 0.7. Trials of patients with asthma or with evidence of reversibility by standard bronchodilator testing were excluded.
The mean age of included participants was 61.6 years, with 70% being male, and 51% being smokers at enrolment. Participants in all trials were stable at the time of enrolment. Budesonide doses were most commonly 640 μg daily, but ranged from 320 to 1280 μg daily. The primary outcome of the review was patient-reported pneumonia as an adverse event or serious adverse event.
Two reviewers independently selected studies for inclusion