Study finds UK lags other high-income countries in diagnosing diabetes

The United Kingdom diagnoses a smaller share of people living with diabetes than most other high-income countries, a new international study found, leaving significant numbers at risk of avoidable complications.

The study estimated that 74.2% of people with diabetes in the UK had received a diagnosis in 2023, versus an average of 79.5% across developed nations. Among western European countries, only Switzerland and France had lower diagnosis rates than the UK. Canada and the United States diagnosed an estimated 86% and 82.8% of cases, respectively.

The analysis, published in Lancet Diabetes and Endocrinology and led by researchers at the University of Washington in Seattle, reported wider global shortfalls in detection and management. Globally, 55.8% of people living with diabetes were estimated to have been diagnosed in 2023. Of those diagnosed worldwide, 91.4% received treatment, but only 41.6% of people on treatment achieved glycaemic control.

In the UK specifically, 88.5% of people with a diagnosed diabetes were reported to be receiving treatment, while 36.2% of treated patients were in control of their blood sugar, the study found. The researchers noted that the analysis did not distinguish between type 1 and type 2 diabetes.

"We find major gaps in diagnosing, treating, and managing diabetes globally, with substantial variation between countries," the authors wrote. They added that although there have been improvements over the past two decades, underdiagnosis and suboptimal glycaemic management remain major challenges, particularly in low- and middle-income countries, and called for strengthened strategies and capacity building to improve detection and care.

Around 4.6 million people in the UK are living with diabetes, health charities and previous estimates show. About nine in 10 of those cases are type 2 diabetes; type 1 accounts for roughly 8% of cases. Public health bodies have previously estimated that about 1.3 million people in the UK may have diabetes but remain undiagnosed.

Medical experts and charities highlighted the clinical consequences of delayed diagnosis. Diabetes is a leading cause of preventable sight loss in people of working age in the UK and is a major contributor to lower-limb amputation, kidney failure and stroke. Without timely diagnosis and effective management, high blood glucose over time increases the risk of these serious complications.

Nikki Joule, policy manager at Diabetes UK, said that underdiagnosis remains a particular problem among younger people and stressed the condition can be hidden by subtle, slowly developing symptoms. "Without a timely diagnosis, dangerously high blood sugar levels go untreated, increasing the risk of serious and life-threatening complications," she said, noting that one in five adults in the UK now live with diabetes or prediabetes.

The findings come amid changes in clinical guidance in England that could affect treatment pathways. In draft guidance published last month, the National Institute for Health and Care Excellence recommended earlier use of GLP-1 receptor agonist medicines — commonly prescribed for weight loss and previously reserved for later-stage type 2 diabetes — and a move away from a single first-line medication approach toward more personalised care. NICE said the changes could prevent complications such as heart failure and heart attacks.

The study's authors and patient groups urged policymakers and health services to increase screening and improve access to effective treatments and long-term management, citing the potential to avert avoidable complications if cases are detected and controlled earlier.

The paper emphasises the need for country-specific strategies informed by better data to close gaps in diagnosis, treatment and glycaemic control, particularly where health systems face resource constraints. It calls for enhanced primary care detection, public awareness campaigns, and broader access to proven therapies to reduce the burden of diabetes worldwide.