Association between diabetes duration and 1‐year prognosis of stroke: A national registry study

BACKGROUND AND PURPOSE: Diabetes mellitus is a strong independent risk factor for stroke recurrence. However, the association between diabetes duration and the prognosis of stroke remains uncertain. We aimed to characterize whether an association exists between diabetes duration and stroke outcomes in patients with ischemic stroke or transient ischemic attack (TIA). METHODS: Between 2015 and 2018, 14,674 patients with ischemic stroke or TIA within 7 days and older than 18 years from the Third China National Stroke Registry (CNSR‐III) were included in this analysis. Diabetes duration at baseline was collected by face‐to‐face interviews and further categorized into groups of without diabetes, diabetes < 4, 4 to <8 and ≥8 years. The association between diabetes duration and clinical outcomes, including stroke recurrence, poor function outcome (modified Rankin Scale score of 3–6), and all‐cause mortality at the 1‐year follow‐up after stroke onset, was evaluated by a multivariable Cox proportional hazard regression model, competing risk model and logistic regression model with adjustment for demographic and clinical features. RESULTS: Among the 14,674 patients included, the average age was 62.0 years, and 68.5% were male. There were 1419 (9.7%) patients who had stroke recurrence, 1912 (13.0%) who had poor function outcome, and 478 (3.3%) who had all‐cause mortality at the 1‐year follow‐up. After adjusting for potential covariates, a diabetes duration ≥8 years was associated with an increased risk of 1‐year stroke recurrence (adjusted hazards ratio [HR], 1.31; 95% CI, 1.05–1.64; p = .02) in comparison to those without Diabetes mellitus. Using a competing risk regression model, a diabetes duration ≥8 years was a significant risk factor for stroke recurrence (HR, 1.31; 95% CI, 1.12–1.53). In contrast, there was no significant association between diabetes duration < 4, 4 to <8 years and clinical outcomes. CONCLUSIONS: Long‐term diabetes duration (≥8 years), but not short‐term diabetes duration, was associated with an increased risk of 1‐year stroke recurrence in patients with ischemic stroke or TIA.