PT  - JOURNAL ARTICLE
AU  - Hitchings, Andrew W
AU  - Lai, Dilys
AU  - Jones, Paul W
AU  - Baker, Emma H
TI  - Metformin in severe exacerbations of chronic obstructive pulmonary disease: a randomised controlled trial
AID  - 10.1136/thoraxjnl-2015-208035
DP  - 2016 Jul 01
TA  - Thorax
PG  - 587--593
VI  - 71
IP  - 7
4099  - http://thorax.bmj.com/content/71/7/587.short
4100  - http://thorax.bmj.com/content/71/7/587.full
SO  - Thorax2016 Jul 01; 71
AB  - Background Severe exacerbations of COPD are commonly associated with hyperglycaemia, which predicts adverse outcomes. Metformin is a well-established anti-hyperglycaemic agent in diabetes mellitus, possibly augmented with anti-inflammatory effects, but its effects in COPD are unknown. We investigated accelerated metformin therapy in severe COPD exacerbations, primarily to confirm or refute an anti-hyperglycaemic effect, and secondarily to explore its effects on inflammation and clinical outcome.Methods This was a multicentre, randomised, double-blind, placebo-controlled trial testing accelerated metformin therapy in non-diabetic patients, aged ≥35 years, hospitalised for COPD exacerbations. Participants were assigned in a 2:1 ratio to 1 month of metformin therapy, escalated rapidly to 2 g/day, or matched placebo. The primary end point was mean in-hospital blood glucose concentration. Secondary end points included the concentrations of fructosamine and C reactive protein (CRP), and scores on the COPD Assessment Test and Exacerbations of Chronic Pulmonary Disease Tool.Results 52 participants (mean (±SD) age 67±9 years) were randomised (34 to metformin, 18 to placebo). All were included in the primary end point analysis. The mean blood glucose concentrations in the metformin and placebo groups were 7.1±0.9 and 8.0±3.3 mmol/L, respectively (difference −0.9 mmol/L, 95% CI −2.1 to +0.3; p=0.273). No significant between-group differences were observed on any of the secondary end points. Adverse reactions, particularly gastrointestinal effects, were more common in metformin-treated participants.Conclusion Metformin did not ameliorate elevations in blood glucose concentration among non-diabetic patients admitted to hospital for COPD exacerbations, and had no detectable effect on CRP or clinical outcomes.Trial registration number ISRCTN66148745 and NCT01247870.