Ethnic differences in SCORE cardiovascular risk in Oslo, Norway

To compare the estimated 10-year risk of cardiovascular death between ethnic Norwegians and five immigrant groups in Norway, according to the European Systematic Coronary Risk Evaluation (SCORE) system.

Data were obtained from the Oslo Health Study and the Oslo Immigrant Health Study (2000-2002). Fourteen thousand eight hundred and fifty-six individuals born between 1940 and 1971 in Norway, Turkey, Iran, Pakistan, Sri Lanka and Vietnam were included in the study. The European SCORE high-risk models, one including total cholesterol and the other including total cholesterol/HDL cholesterol ratio, were used to estimate 10-year cardiovascular mortality risk. A model assuming no smoking was also applied. Age was projected to 60 years and estimates were adjusted for age at screening.

Norwegians had higher total cholesterol and systolic blood pressure, but lower triglycerides and higher HDL cholesterol compared with immigrants. The mean SCORE (total cholesterol model) varied between 6.6% (Turkey) and 5.4% (Sri Lanka) in men, and 2.1% (Norway) and 1.5% (Pakistan, Sri Lanka and Vietnam) in women. Application of the ratio model gave higher estimated risk in all immigrant groups except for Vietnamese, with 10-year risk varying between 7.7% (Turkey/Pakistan) and 5.7% (Vietnam) in men, and 2.0% (Norway) and 1.5% (Vietnam) in women. When the ratio model was applied assuming no smoking in all ethnic groups, the mean SCORE risk was reduced by 30% in Turkish men and 25% in Norwegian women, with less significant reductions observed in the other groups.

Norwegians ranked high with the SCORE total cholesterol model and Norwegian men low with the SCORE ratio model. Although the predictive accuracy of the SCORE models for immigrants in Norway remains to be evaluated, our findings suggest that the ratio model could be more applicable to the entire population in Norway.