Validation of Cardiovascular Risk Prediction by the Arriba Instrument.

Background: It is recommended in cardiovascular prevention guidelines that treatment should be based on overall cardiovascular risk. The arriba instrument has been widely used for this purpose in Germany. The aim of this study is to validate risk prediction by arriba with the aid of morbidity and mortality data from the population- based Study of Health in Pomerania.

Methods: In a longitudinal analysis, the arriba instrument was used to calculate the 10-year overall cardiovascular risk at baseline for subjects who had not sustained any prior cardiovascular event. Cardiovascular event rates were determined from follow-up data, and discrimination and calibration measures for the risk determination algorithm were calculated.

Results: Data from 1973 subjects (mean age 51 ± 13 years, 48% men) were included in the analysis. After a median follow-up of 10.9 years, cardiovascular events had occurred in 196 subjects, or 9.8%. The ratio of predicted to observed event rate was 0.8 (95% confidence interval: [0.5; 1.1]), 1.3 [1.0; 1.8], and 1.1 [0.8; 1.4] for subjects at low, intermediate, and high cardiovascular risk, respectively. Arriba underestimated cardiovascular event rates in women and overestimated them in persons aged 30-44 and 45-59. The area under curve was 0.84 [95% CI 0.81; 0.86].

Conclusion: The discrimination scores of the arriba instrument resemble those of SCORE-Germany and PROCAM, but a better adjustment to the target population would be desirable. The results support the recommendation of the German Guideline for Cardiovascular Risk Counseling in General Practice for the use of the arriba instrument. An unresolved problem is the failure to consider intervention effects, resulting in an overall mild overestimation of risk.