Adding ethnicity to cardiovascular risk prediction: external validation and model updating of SCORE2 using data from the multiethnic HELIUS population cohort

Abstract Background Current prediction models for mainland Europe do not include ethnicity, despite ethnic disparities in cardiovascular disease (CVD) risk. Purpose We evaluated the performance of SCORE2 across the largest ethnic groups in the Netherlands with and without the factor of ethnicity. Methods We linked data from 11,614 participants enrolled between 2011 and 2015 in the prospective, multi-ethnic HELIUS cohort study, the Netherlands, aged between 40 and 70 years without CVD with hospital data. Variables (age, sex, smoking status, blood pressure, cholesterol) and outcome first CVD event (myocardial infarction, stroke, CVD death) were consistent with SCORE2. We used Fine and Gray models to calculate sub-distribution hazard ratios (SHR) for South-Asian Surinamese, African Surinamese, Ghanaian, Turkish and Moroccan origin groups, relative to the Dutch origin group, on top of individual SCORE2 risk predictions. Model performance was evaluated by discrimination, calibration and net reclassification index (NRI). Results Overall, 274 fatal and non-fatal CVD events, and 146 non-cardiovascular deaths were observed during a median of 7.8 years follow-up (IQR 6.8–8.8). SHRs for CVD events were 1.86 (95% CI 1.31-2.65, p=0.0005) for the South-Asian Surinamese, 1.09 (95% CI 0.76-1.56) for the African-Surinamese, 1.48 (95% CI 0.94-2.31) for the Ghanaian, 1.63 (95% CI 1.09-2.44, p=0.018) for the Turkish, and 0.67 (95% CI 0.39-1.18) for the Moroccan origin groups. Adding ethnicity to SCORE2 led to comparable calibration and discrimination [0.76 (0.74-0.79) vs. 0.77 (95% CI 0.74-0.78)]. The NRI for adding ethnicity to SCORE2 was 0.24 (95% CI 0.18-0.31) for events and -0.12 (95% CI -0.13--0.12) for non-events. Conclusion Adding ethnic backgrounds improves risk classification of the SCORE2 risk prediction model in a middle-aged, multi-ethnic Dutch population, which may help to address disparities in CVDs through timely treatment.