DENVER – Among patients hospitalized for chronic obstructive pulmonary disease (COPD) exacerbations, acute administration of metformin had no detectable impact on clinical recovery, based on results from a single-center study.
Patients hospitalized for COPD exacerbations are more likely to have longer hospital stays and to experience adverse outcomes if their blood glucose levels are elevated, Emma H. Baker, Ph.D., said in an interview at an international conference of the American Thoracic Society.
Dr. Emma H. Baker
“The aim of the current study was to see if lowering blood glucose in COPD patients would reduce adverse outcomes,” said Dr. Baker, professor of clinical pharmacology at the Institute for Infection and Immunity at St. George’s University of London. A previous study suggested that tight glycemic control with insulin improved outcomes among COPD patients in the intensive care unit; however, a large, randomized, multicenter trial showed no difference in outcomes and a risk for hypoglycemia. The researchers wanted to see whether metformin would prove a safer option.
Dr. Baker and her associates randomized 51 patients in a 2:1 fashion to receive metformin or placebo. The metformin dose was escalated to 2 g/day over 4 days and continued for 1 month. Outcome measures included the Exacerbations of Chronic Pulmonary Disease Tool (EXACT), the COPD Assessment Test (CAT), and the rates of recurrent health care use events such as antibiotic or steroid prescription and readmission to the hospital. Of the 51 patients, 34 received metformin and 18 received placebo. The mean age of study participants was 67 years and 39% were women.
Compared with baseline, the EXACT scores improved by 4.2 points at day 5, 5-7 points at day 10, and 6.3 points at day 28 (P < .05 for all). However, the researchers observed no significance differences between the metformin and placebo groups in terms of improvements on EXACT scores. Similarly, CAT scores improved by a mean of 4.2 points over the course of the study, largely during the time between baseline and hospital discharge. There were no significant differences between the metformin and placebo groups at any time point. Meanwhile, the median time to a recurrent health care use event was similar between the groups (46 days in the metformin group, compared with 40 days in the placebo group; P = .682).
“Metformin works through reducing hepatic glucose output and increasing insulin sensitivity – and the effect may take several months,” Dr. Baker said. “What we did show is that metformin seems to be safe in COPD patients,” with no evidence of lactic acidosis.
Diabetes and hyperglycemia are very common in COPD, and were associated with more frequent COPD exacerbations and worse outcomes from exacerbations, according to Dr. Baker.
The study was sponsored by the Medical Research Council of the United Kingdom and the British Lung Foundation. Dr. Baker reported having no relevant financial conflicts.
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