Life's Essential 8, phenotypic age, and cardiovascular age in prediabetes: predictive value in the UK Biobank and protein mediation in cardiovascular-diabetes comorbidity.

Lifestyle improvement may help reverse prediabetes. Indicators such as Life's Essential 8 (LE8) and biological aging measures (phenotypic age, cardiovascular biological age) partially reflect metabolic status in prediabetes, but their predictive value for cardiovascular mortality and stroke in this population remains unclear. We analyzed data from 74,678 White participants with prediabetes in the UK Biobank, defined by either HbA1c (5.7-6.4%) or fasting glucose (6.1-6.9 mmol/L). Follow-up continued until October 10, 2023. Cox regression was used to examine associations between LE8, phenotypic age (PhenoAge), cardiovascular biological age (CBA), and outcomes of cardiovascular (CVD) mortality and stroke. Restricted cubic spline (RCS) models identified biological age risk thresholds. Mediation analysis assessed whether proteins such as CST3, EFEMP1, FES, IGFBP2, IGFBP6, LPA, PCSK9, and TIMP1 mediated these effects. Over a median follow-up of 13.4 years, 2263 participants died from CVD causes. Each 1-year increase in CBA or PhenoAge was associated with a ~ 10% higher risk of CVD mortality (CBA aHR = 1.10; PhenoAge aHR = 1.09; both P < 0.001), while each 1-point increase in LE8 score was linked to a 3% lower risk (HR = 0.97, P < 0.001). The risk biological ages for these two indicators were also identified: PhenoAge ≥ 58.52 years and CBA ≥ 62.42 years. Similar trends were observed for stroke. Mediation analysis revealed that CST3, TIMP1, IGFBP2, and IGFBP6 contributed to the biological pathways between aging/lifestyle and CVD outcomes. The combined LE8 and PhenoAge model showed the strongest predictive performance for CVD mortality (AUC = 0.716) and stroke (AUC = 0.638) over 15 years. LE8 combined with phenotypic age provides prognostic value for CVD outcomes in prediabetes. These findings highlight the potential of lifestyle modification and delayed biological aging in reversing prediabetes and underscore comorbidity-related proteins as promising therapeutic targets.