Reversion of Prediabetes to Normoglycemia Linked to 68% Lower Diabetes Risk

This systematic review and meta-analysis examined the association between reversion of prediabetes to normoglycemia and the risk of incident diabetes, cardiometabolic disease, and mortality. The study included 535,066 participants with prediabetes from multiple cohorts. The intervention or exposure of interest was reversion of prediabetes to normoglycemia, compared with persistent prediabetes or progression from prediabetes to diabetes. The primary outcomes were incident diabetes, incident cardiometabolic disease, and mortality. Secondary outcomes included incident cardiovascular disease (CVD), CVD mortality, and all-cause mortality. Follow-up duration was not reported.

For the primary outcome of incident diabetes, reversion to normoglycemia was associated with a 68% lower risk compared with persistent prediabetes (HR: 0.32; 95% CI: 0.25, 0.43). Absolute numbers were not reported. For incident cardiovascular disease, there was no significant difference between groups (HR: 0.98; 95% CI: 0.94, 1.02). Similarly, CVD mortality (HR: 0.84; 95% CI: 0.65, 1.10) and all-cause mortality (HR: 0.97; 95% CI: 0.92, 1.02) showed no significant associations. However, when comparing reversion to normoglycemia versus progression to diabetes, reversion was associated with a lower risk of CVD (HR: 0.75; 95% CI: 0.63, 0.88).

Safety and tolerability data were not reported in this meta-analysis. The study did not provide information on adverse events, serious adverse events, discontinuations, or tolerability. Limitations noted by the authors include that evidence regarding the impact on CVD and mortality remained inconclusive. The study design does not allow for causal conclusions, as it is based on observational associations.

Compared to prior landmark studies in this therapeutic area, these findings align with previous research suggesting that lifestyle interventions or pharmacotherapy can reverse prediabetes and reduce diabetes incidence. However, the lack of significant benefit for CVD and mortality outcomes contrasts with some earlier trials that showed cardiovascular benefits with glucose-lowering interventions in diabetes. The inconclusive results for CVD and mortality may reflect the relatively short follow-up or the heterogeneity of included studies.

Key methodological limitations include the observational nature of the included studies, which precludes causal inference. The meta-analysis may be subject to confounding, as individuals who revert to normoglycemia may have healthier lifestyles or other protective factors. Additionally, the definition of prediabetes and normoglycemia may vary across studies, and the duration of follow-up was not reported, which could affect the assessment of long-term outcomes.

Clinically, these results suggest that achieving normoglycemia in patients with prediabetes is strongly associated with a reduced risk of developing diabetes. However, the lack of significant association with CVD and mortality indicates that reversion alone may not be sufficient to lower cardiovascular risk. Clinicians should continue to emphasize comprehensive cardiovascular risk factor management in patients with prediabetes, regardless of glycemic status.

Several questions remain unanswered. It is unclear whether the association between reversion and lower diabetes risk is causal or due to confounding. The optimal strategies to achieve and sustain normoglycemia, and their long-term effects on CVD and mortality, need further investigation. Additionally, the impact of reversion on other outcomes such as microvascular complications was not addressed. Future research should focus on randomized trials with longer follow-up to clarify these relationships.