Development and external validation of risk scores for cardiovascular hospitalisation and rehospitalization in patients with diabetes

Context: Cardiovascular disease (CVD) is a common and costly reason for hospitalization and rehospitalization among patients with type 2 diabetes. Objective: This study aimed to develop and externally validate two risk-prediction models for cardiovascular hospitalization and cardiovascular rehospitalization. Design: Two independent prospective cohorts. Setting: The derivation cohort includes 4704 patients with type 2 diabetes from 18 general practices in Cambridgeshire. The validation cohort comprises 1121 patients with type 2 diabetes from post-trial follow-up data. Main Outcome Measure: Cardiovascular hospitalization over 2 years and cardiovascular rehospitalization after 90 days of the prior CVD hospitalization. Results: The absolute rate of cardiovascular hospitalization and rehospitalization was 12.5% and 6.7% in the derivation cohort and 16.3% and 7.0% in the validation cohort. Discrimination of the models was similar in both cohorts, with C statistics above 0.70 and excellent calibration of observed and predicted risks. Conclusion: Two prediction models that quantify risks of cardiovascular hospitalization and rehospitalization have been developed and externally validated. They are based on a small number of clinical measurements that are available for patients with type 2 diabetes in many developed countries in primary care settings and could serve as the tools to screen the population at high risk of cardiovascular hospitalization and rehospitalization.