Trends and Risk Factors Associated With Stroke Recurrence in China, 2007-2018

Importance: Recurrent stroke rates have decreased substantially in Western countries. However, data on changes in stroke recurrence and risk factor patterns in China are limited. Objective: To systematically assess stroke recurrence trends by evaluating temporal improvement in guideline-recommended secondary prevention treatment performance and changes in risk factor patterns over 10 years in China. Design, Setting, and Participants: This post hoc cohort study was conducted based on data from the China National Stroke Registries (CNSRs, comprising 3 phases, I-III, from 2007-2018). Participants were patients with ischemic stroke who were enrolled in CNSR I or III within 7 days of symptom onset. Data were analyzed from September through November 2021. Exposures: Vascular risk factors included current smoking, alcohol consumption, hypertension, diabetes, coronary artery disease, atrial fibrillation, and low-density lipoprotein cholesterol (LDL-C) levels. Main Outcomes and Measures: The cumulative incidence rates of stroke recurrence at 3, 6, and 12 months were calculated, and the performance of guideline-based secondary prevention treatments was investigated at each visit in CNSR I (2007-2008) and III (2015-2018). Logistic regression models were used to evaluate changes in risk factor patterns for stroke recurrence based on data from CNSR I and III. Results: A total of 10 952 patients with ischemic stroke from CNSR I (6740 61.5% men; median IQR age, 67 57-75 years) and 10 348 patients with ischemic stroke from CNSR III (7128 68.9% men; median IQR age, 63 54-70 years) were selected. Over 10 years, the adjusted cumulative incidence of recurrent stroke within 12 months decreased from 15.5% (95% CI, 14.8%-16.2%) to 12.5% (95% CI, 11.9%-13.1%) (P < .001). Factors associated with increased risk of stroke in CNSR I that were still associated after 10 years included age per 10 years (CNSR I: odds ratio OR, 1.24; 95% CI, 1.18-1.31; CNSR III: OR, 1.08; 95% CI, 1.01-1.15), prior stroke (CNSR I: OR, 1.62; 95% CI, 1.45-1.82; CNSR III: OR, 1.66; 95% CI, 1.44-1.92), coronary heart disease (CNSR I: OR, 1.21; 95% CI, 1.04-1.40; CNSR III: OR, 1.23; 95% CI, 1.02-1.49), and LDL-C level per 10 mg/dL (0.259 mmol/L) (CNSR I: OR, 1.02; 95% CI, 1.01-1.04; CNSR III: OR, 1.02; 95% CI, 1.00-1.03), whereas atrial fibrillation (CNSR I: OR, 1.51; 95% CI, 1.26-1.81; CNSR III: OR, 0.95; 95% CI, 0.74-1.23) was no longer an independent risk factor in 2015 to 2018. Conclusions and Relevance: This study found that stroke recurrence rate in China decreased significantly, but approximately 12.5% of patients still experienced stroke recurrence within 12 months. These findings suggest that more intensive control of traditional risk factors, including LDL-C levels, may be needed to further reduce stroke recurrence.