Treatments to reduce blood sugar levels do more harm than good in many type 2 diabetes patients, particularly older people.

This is the eye-catching conclusion of research from University College London, the University of Michigan and the Ann Arbor Veterans Affairs Hospital. A study, published in JAMA Internal Medicine, found that for many people the benefits of taking diabetes medications “are so small that they are outweighed by the minor harms and risks associated with treatment”.

The researchers argue that the benefits of treatment decline with age and indeed the risk outweighs those benefits by the age of 75. They argue that it depends less on their blood sugar level than their age “and the hassles and side-effects of the treatment”.

Their claims are based primarily on a 20-year study of type 2 diabetes treatments involving 5,102 people in the UK, where people with an A1c above 6.5% can be diagnosed with diabetes. The researchers looked at how effective diabetes treatments were at preventing associated complications, such as kidney, eye and heart disease in tandem with the increased risk of side-effects and the burden of taking pills or injections.

John Yudkin of UCL and co-author of the paper, said that a typical person with type 2 diabetes who begins treatment at age 45 and reduces their A1c by 1% “may gain up to ten months of healthy life. At age 75, they may gain as little as three weeks of healthy life. Whether this is worth 10-15 years of pills and injections with potential side-effects is ultimately up to the patient”.

He added that “ultimately, the aim of a treatment is not to lower blood sugar for its own sake but to prevent debilitating or deadly complications,”. If the risk of these complications “is suitably low and the burden of treatment correspondingly high, treatment will do more harm than good. The balance between the two can never be defined by a simple figure like blood sugar level”.

Lead author Sandeep Vijan, Professor of Internal Medicine at the U-M Medical School, agreed, saying that “if you’re having low blood sugars, gaining weight or find frequent insulin shots to be disruptive to your daily life – all for minimal health benefits – the drugs are doing more harm than good”.

Commenting on the study, Simon O’Neill, director of health intelligence at Diabetes UK, noted that “clearly, everyone with type 1 diabetes needs to have insulin to stay alive” but for type 2, s”ometimes there is a balance to be struck where certain medications might help give someone a longer life but also cause side effects that might negatively impact on quality of life.”

He added that the study “highlights the importance of looking at the individual needs of the person with type 2 diabetes, rather than adopting a blanket approach”.