Validation of the Systematic COronary Risk Evaluation - Older Persons (SCORE-OP) in the EPIC-Norfolk prospective population study

Abstract

Background: The Systematic COronary Risk Evaluation -Older Persons (SCORE-OP) algorithm is developed to assess 10-year risk of death due to cardiovascular disease (CVD) in individuals aged ≥65 years. We studied the performance of SCORE-OP in the European Prospective Investigation of Cancer Norfolk (EPIC-Norfolk) prospective population cohort. Methods: 10-year CVD mortality as predicted by SCORE-OP was compared with observed CVD mortality among individuals in the EPIC-Norfolk cohort. Persons aged 65-79 years without known CVD were included in the analysis. CVD mortality was defined as death due to ischemic heart disease, cardiac failure, cerebrovascular disease, peripheral-artery disease or aortic aneurysm. Predicted 10-year CVD mortality was calculated by the SCORE-OP algorithm, and compared to observed mortality rates. The area under the receiver operator characteristics curve (AUROC) was calculated to evaluate discriminative power. Calibration was evaluated by calculating ratios of predicted vs observed mortality and by Hosmer-Lemeshow tests. Results: A total of 6590 individuals (45.8% men), mean age 70.2 years (standard deviation 3.3) were included. The predicted mortality by SCORE-OP was 9.84% (95% confidence interval (CI) 9.76-9.92) and observed mortality was 10.2% (95% CI 9.52-11.04), ratio 0.96. AUROC was 0.63 (95% CI 0.60-0.65), and X 2 was 3.3 (p = 0.92). Conclusion: SCORE-OP overall accurately estimates the rate of CVD mortality in a general population aged 65-79 years. However, while calibration is excellent, the discriminative power of the SCORE-OP is limited, and as such cannot be readily implemented in clinical practice for this population.

Performance of risk prediction scores for cardiovascular mortality in older persons: External validation of the SCORE OP and appraisal

“…In our cohort comprised of older persons, we found that SCORE OP yielded higher risk estimates than SCORE (with mathematical correction). The same result was found in the only published external validation of the SCORE OP [24]. While the authors attributed this inconsistency with the previous cross-sectional study [35,36] to a difference in the methods used, we think it may have arisen because of a difference in age composition of the participants.…”

“…Their results about the transportability of the SCORE OP and SCORE among older persons were divergent compared to ours. In this UK population, the SCORE OP showed "excellent calibration", performing better than the SCORE, despite showing low discrimination ability [24]. Interestingly, in this UK cohort, diabetes prevalence was extremely low, around 3% [24], likely because this information was only self-reported.…”

“…In this UK population, the SCORE OP showed "excellent calibration", performing better than the SCORE, despite showing low discrimination ability [24]. Interestingly, in this UK cohort, diabetes prevalence was extremely low, around 3% [24], likely because this information was only self-reported. This observation provides additional support for our aforementioned argument that the definition of diabetes plays a crucial role in the transportability of the SCORE OP.…”

“…Recently, the SCORE OP was subjected to external validation for the first time in a cohort of 6,590 older individuals aged between 65 and 79 living in Norfolk, UK [24]. Their results about the transportability of the SCORE OP and SCORE among older persons were divergent compared to ours.…”

“…Until recently, the SCORE OP had not been externally validated; the newly published study calls for further validations of this risk tool [24]. Our objective was to assess calibration and discrimination of SCORE OP in a prospective cohort study of individuals aged �70 in Berlin.…”