Why in news?
A recent clinical study reported that metformin, a widely prescribed diabetes drug, may blunt some of the cardiovascular benefits of exercise. This finding has led doctors to re‑examine how the drug is used alongside lifestyle interventions in people at risk of metabolic diseases.
Background
Metformin (1,1‑dimethylbiguanide hydrochloride) belongs to the biguanide class of drugs. It is considered the first‑line medication for managing type‑2 diabetes and is included in the World Health Organization’s Model List of Essential Medicines. The drug lowers blood glucose by decreasing absorption of sugar from food, reducing glucose production by the liver and improving the body’s response to insulin. It has been in use for decades, is inexpensive and generally safe, although it can cause mild gastrointestinal discomfort, a metallic taste or, rarely, lactic acidosis in people with severe kidney impairment.
Study findings
- Design: The study, published in The Journal of Clinical Endocrinology & Metabolism, recruited 72 adults at high risk of developing metabolic syndrome. Participants were randomised to low‑ or high‑intensity exercise programmes and received either metformin or a placebo.
- Results: Exercise alone improved blood vessel insulin sensitivity and markers of inflammation. However, participants taking metformin experienced smaller gains in these measures compared with those on placebo. Their improvements in aerobic fitness and fasting glucose were also muted.
- Interpretation: Researchers suggested that metformin might interfere with cellular adaptations triggered by exercise. Despite this, they emphasised that metformin still provides substantial glucose‑lowering benefits and should not be discontinued without medical advice.
Implications
- Personalised treatment: Doctors may need to adjust exercise intensity or monitor patients more closely when prescribing metformin alongside exercise regimens.
- Further research: Larger studies are needed to confirm these findings and explore the mechanisms behind the interaction between metformin and exercise.