New real-world evidence from an international clinical audit suggests that testosterone replacement therapy (TRT) may help improve blood sugar control in men with type 2 diabetes who also have low testosterone levels.
The findings, presented at the Annual Meeting of the European Association for the Study of Diabetes (EASD) in Hamburg, come from an ongoing worldwide audit tracking testosterone deficiency treatment in routine clinical practice. Early results indicate that TRT may reduce HbA1c levels — a key marker of long-term blood glucose control — for up to two years after treatment begins.
Why It Matters
Low testosterone is common in men with type 2 diabetes, with researchers estimating that around 40% may also have symptomatic testosterone deficiency. This hormonal imbalance has been associated with higher cardiovascular risk, poorer mental wellbeing, osteoporosis, and an increased risk of death.
Although previous studies have suggested TRT can improve insulin resistance, body weight, cholesterol levels, quality of life, and sexual health, adoption has remained limited due to historical concerns over heart-related side effects.
More recent large-scale research, however, has found no significant difference in major cardiovascular events between men receiving testosterone therapy and those given a placebo.
What the Audit Found
The audit, led by the Association of British Clinical Diabetologists (ABCD), has so far collected anonymised patient data from 34 centres across eight countries, including the UK, Germany, Canada, New Zealand, South Africa, Malaysia, and Vietnam.
A total of 428 men with an average age of 71 have been included so far. Patients were treated using testosterone gels or long-acting testosterone injections.
Researchers found HbA1c levels improved steadily over time. After three months of treatment, average HbA1c fell from 71 to 66 mmol/mol. After 12 months, it dropped further to 61.7 mmol/mol. By 24 months, average HbA1c had declined to 55 mmol/mol.
These results suggest testosterone therapy may continue improving metabolic health over time, potentially through reduced insulin resistance and lower body fat levels.
Expert Perspective
Professor Hugh Jones of Barnsley Hospital, who led the study, said awareness of the link between testosterone deficiency and diabetes remains low among many clinicians.
He said the expanding audit could help identify which patients are most likely to benefit from treatment while also providing stronger evidence for doctors to screen men with type 2 diabetes for symptoms of testosterone deficiency.
What Comes Next
Researchers stress that more long-term data involving larger patient groups is still needed. However, these early findings add to growing evidence that carefully managed testosterone therapy could become an important treatment option for some men with type 2 diabetes and low testosterone.
If confirmed, the results may encourage more proactive testing and treatment as part of routine diabetes care.
