Effect of metformin on lung function in diabetic or prediabetic individuals with respiratory disease

The effect of oral metformin on spirometry, exercise capacity and quality of life in adults with chronic obstructive pulmonary disease (COPD) and either diet-controlled type 2 diabetes mellitus or impaired glucose tolerance.

Status

Completed

Phases

Phase 2

Study type

Interventional

Source

ANZCTR

Registry ID

ACTRN12610000378022

Enrollment

Registered

2010-05-11

Start date

2011-06-09

Completion date

2012-05-07

Last updated

2020-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

Diabetes mellitus is known to cause damage to many organs, but its effects of the lungs are underrecognised. Diabetes is commonly associated with reduced lung volumes and impairment of other aspects of respiratory function; the cause is unknown. The effect of antidiabetic treatments on respiratory function is also largely unknown. Metformin is an oral antidiabetic agent which improves blood sugar levels and directly improves insulin resistance. Metformin is also safe for use in prediabetic and nondiabetic individuals. If metformin can improve lung function in diabetes, this could provide a way to treat diabetic and prediabetic patients with cardiorespiratory disease, as well as providing information about how diabetes affects respiratory function. We plan to evaluate the effect of 6 months of metformin treatment on lung volumes and other relevant outcomes in a group of 40 subjects with chronic obstructive pulmonary disease (COPD, emphysema) and impaired glucose tolerance or diet-controlled diabetes.

Interventions

Oral metformin 850mg twice daily for 6 months.

Study design

Allocation

Non-randomised trial

Intervention model

Single group

Primary purpose

Treatment

Masking

Open (masking not used)

Eligibility

Sex/Gender

All

Age

45 Years to No maximum

Healthy volunteers

Inclusion criteria

* Obese (body mass index > 30) * Central pattern of obesity (elevated waist circumference) * Impaired glucose tolerance or diet-controlled type 2 diabetes mellitus (previous diagnosis, or evidence of blood tests meeting American Diabetes Association 2010 criteria) * Post-bronchodilator spirometry that is consistent with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage 2+ COPD * Symptomatic: Medical Research Council dyspnoea score of 2 or higher

Exclusion criteria

1. Currently taking oral hypoglycaemic agent or insulin 2. Active respiratory disease other than obstructive airways disease 3. Exacerbation of airways disease requiring change in treatment within the preceding 6 weeks 4. Participation in pulmonary rehabilitation programme within the past 6 weeks 5. Currently prescribed long term oral corticosteroids 6. Renal impairment (estimated glomerular filtration rate < 45 mL/min) 7. Cirrhosis, impaired synthetic liver function, or liver failure 8. Chronic respiratory failure 9. Congestive heart failure 10. Current or recent habitual heavy alcohol intake 11. Current use of antiretroviral medication 12. Pregnancy 13. History of lactic acidosis 14. Allergy to metformin 15. Unable to comply with the study procedures or protocol

Outcome results