Lowering blood sugar levels in people with prediabetes can significantly reduce the risk of serious heart problems, according to new research from King's College London. The study, published in The Lancet Diabetes & Endocrinology, found that returning blood glucose to normal levels—effectively reversing prediabetes—reduces the likelihood of death from heart disease or hospital admission for heart failure by more than 50%.
The research comes as previous studies have shown that lifestyle changes such as increased exercise, weight loss, and dietary improvements do not lower cardiovascular risk in people with prediabetes. This new evidence suggests a different approach may be needed.
"This study challenges one of the biggest assumptions in modern preventative medicine. For years, people with prediabetes have been told that losing weight, exercising more and eating healthier will protect them from heart attacks and early death. While these lifestyle changes are unquestionably valuable, the evidence does not support that they reduce heart attacks or mortality in people with prediabetes. Instead, we show that remission of prediabetes is associated with a clear reduction in fatal cardiac events, heart failure, and all-cause mortality," said Dr Andreas Birkenfeld, Reader in Diabetes at King's College London and University Hospital Tuebingen.
Prediabetes is defined by higher-than-normal blood glucose levels that are not yet high enough for a type 2 diabetes diagnosis. It often progresses to type 2 diabetes but also increases the risk of cardiovascular disease—a leading cause of death worldwide. In the UK, about one in five adults has diabetes or prediabetes; this figure rises to over one in three adults in the United States and four out of ten adults in China. Globally, more than one billion people are estimated to have prediabetes.
The study led by Dr Birkenfeld reanalysed data from two major diabetes prevention trials: the US Diabetes Prevention Program Outcomes Study (DPPOS) and the Chinese DaQing Diabetes Prevention Outcomes Study (DaQingDPOS). Both studies followed participants with prediabetes over several decades while encouraging interventions like increased exercise and healthy eating.
Findings showed that individuals who achieved remission from prediabetes had a 58% lower risk of cardiovascular death or hospitalization due to heart failure. This benefit lasted for decades after normalizing glucose levels. Additionally, those who achieved remission saw a 42% reduction in risk for heart attack, stroke, and other major adverse cardiovascular events. These results were consistent across both Chinese and US populations studied.
Previous analyses had indicated that combined lifestyle interventions did not reduce cardiovascular disease among participants. Researchers suggest this means simply delaying diabetes onset does not ensure protection against cardiovascular issues unless significant metabolic changes occur.
"The study findings mean that prediabetes remission could establish itself - alongside lowering blood pressure, cutting cholesterol and stopping smoking – as a fourth major primary prevention tool that truly prevents heart attacks and deaths," added Dr Birkenfeld.
This research is part of an ongoing collaboration between King's College London and TUD Dresden University of Technology under their transCampus partnership.
"The transCampus is a unique partnership established by King's College London and the TUD Dresden University of Technology as a transnational strategic partnership based on the idea of true cooperation and an intense dedication for collaboration in all fields. Guided by shared ideas, values and a devotion to research and education, transCampus enables researchers to work together beyond the means of a traditional partnership by sharing resources, combining their strength, and promoting transnational projects and knowledge transfer," said Professor Stefan Bornstein, Dean of transCampus.
