Patients with type 2 diabetes who lose at least 15% of their weight within two years of diagnosis cut their risk of major vascular complications, research has found.

The study, published in Diabetes Care [link here], used primary care records from the UK’s Clinical Practice Research Datalink (CPRD) Aurum database to track more than 72,000 adults with obesity and type 2 diabetes diagnosed between 2000 and 2024.

Researchers identified 14,496 patients who achieved at least 15% weight loss within two years of their diagnosis. Each was matched with four control patients whose weight stayed stable, defined as less than 2% change, giving a control group of 57,984.

The two groups were well balanced at baseline, with similar age (mean 53 years), HbA1c (around 8%) and BMI (37.9 kg/m² in controls versus 38.8 kg/m² in the weight loss group).

Over a mean follow-up of close to seven years, the weight loss group had a 14% lower risk of a first macrovascular event (myocardial infarction, stroke, angina or peripheral arterial disease), with a hazard ratio of 0.86 (95% CI 0.81–0.91), and a 10% lower risk of a first microvascular event (chronic kidney disease, retinopathy or neuropathy), with a hazard ratio of 0.90 (95% CI 0.86–0.94).

Looking at individual outcomes, the weight loss group had significantly lower risks of myocardial infarction (HR 0.83), angina (HR 0.85), chronic kidney disease (HR 0.91) and retinopathy (HR 0.85). Differences in stroke (HR 0.89), peripheral arterial disease (HR 0.90) and neuropathy (HR 0.94) trended the same way but did not reach statistical significance.

The metabolic gains were notable in the first year after the index weight loss. Among those with available HbA1c results, 78% of the weight loss group hit the NICE target of 6.5% or below, compared with 31% of controls, and a third reached normoglycaemia (HbA1c below 5.7%) versus just 3% of controls. A blood pressure target of below 130 mmHg was met by 48% of the weight loss group versus 32% of controls.

By year four, these gaps had narrowed but persisted, with 59% of the weight loss group at the HbA1c target versus 27% of controls, and 41% versus 36% on blood pressure. Crucially, the weight loss group achieved these results while using fewer antidiabetic drugs, antihypertensives and statins than controls throughout the four years of follow-up.

The authors said the findings were “clinically meaningful”, noting they applied to a relatively young cohort with substantial obesity at diagnosis. While acknowledging an observational design “precludes definitive causal inference”, they argued the overall pattern of results was “biologically and epidemiologically coherent” with trial evidence from DiRECT and the SELECT semaglutide trial, both of which linked weight and waist circumference reductions to better metabolic and cardiovascular outcomes.

They also flagged that patients motivated to lose substantial weight early may differ from controls in ways the propensity matching could not capture, such as diet and physical activity, and that whether the weight loss was intentional could not be confirmed from the records.

The study was funded by Novo Nordisk, with several authors on the paper also employees and shareholders of the company.