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, 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], 124; 95% CI, 1.18-1.31; CNSR 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 OR, 1.21; 95% CI, 1.04-1.40; CNSR III: OR, 123; 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 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.