PREDIABETES is increasingly recognised as a critical warning stage before the onset of type 2 diabetes, particularly as rates rise among younger and working-age adults. While it is often described as a reversible condition, real-world data on how long people remain prediabetic, and how often they progress to diabetes, have been limited, especially in low- and middle-income countries. New findings from a decade-long hospital-based study in India provide important insight into the natural history of prediabetes and the window of opportunity for prevention.
Tracking Prediabetes Over Time in a Real-World Setting
Researchers analysed electronic medical records from a government hospital, following 1,670 diabetes-free adults aged 30 years and older for up to 10 years. Using a multistate statistical model, the study examined how individuals moved between three metabolic states: normoglycaemia (normal blood sugar), prediabetes, and type 2 diabetes.
This approach allowed investigators not only to estimate how frequently diabetes developed, but also how long people stayed in the prediabetic phase and how often blood sugar levels returned to normal.
Prediabetes Carries a Much Higher Diabetes Risk
The results show a stark difference in diabetes risk depending on baseline glycaemic status. Overall, the incidence of type 2 diabetes was approximately 21 cases per 1,000 person-years. However, among individuals who already had prediabetes at baseline, the incidence rate doubled to more than 41 cases per 1,000 person-years, compared with just under 16 cases per 1,000 person-years in those with normal blood sugar.
Over time, nearly one in three people with prediabetes progressed to diabetes, highlighting how dangerous this “in-between” state can be if left unaddressed.
Reversal of Prediabetes Is Common, But Time Limited
Encouragingly, the study also found that prediabetes is far from a one-way pathway. Reversion from prediabetes back to normal blood sugar levels peaked at around 60% within the first two to three years after diagnosis. However, this reversal rate declined with longer duration, suggesting that early action is crucial. Once individuals remain in the prediabetic state for several years, the likelihood of spontaneous improvement drops, and the risk of progression increases.
Sex Differences in Prediabetes Outcomes
Notably, the study identified important sex-based differences. Men were more likely to progress from prediabetes to diabetes, while women showed higher rates of reversion to normoglycaemia. These findings may reflect biological differences, lifestyle factors, or healthcare-seeking behaviours, and suggest that prevention strategies may need to be tailored accordingly.
Why Early Detection of Prediabetes Matters
Taken together, these findings reinforce the idea that prediabetes represents a critical intervention window. Routine screening, particularly in adults over 30 years, can identify individuals at high risk before irreversible metabolic damage occurs. Lifestyle changes, such as improved diet, increased physical activity, and weight management, are most effective when introduced early in the prediabetic phase.
Reference
Sharma P et al. Transition between prediabetic and diabetic stages in an urban community in india: a decade-long retrospective cohort study. J Diabetes Metab Disord. 2025;24(2):270.
