Place of cardiovascular risk prediction models in South Asians; agreement between Framingham risk score and WHO/ISH risk charts

Abstract

There are no cardiovascular risk prediction models developed in South Asian cohorts. Therefore, different risk models not validated in South Asians are being used. We aimed to compare cardiovascular risk predictions of Framingham risk score (FRS) and World Health Organization/International Society of Hypertension (WHO/ISH) charts for agreement in a sample of South Asians. Ten-year cardiovascular risk predictions of patients without previous cardiovascular diseases attending a non-communicable disease clinic were calculated using FRS (with BMI and with cholesterol) and WHO/ISH charts (with and without cholesterol). Patients were categorised into low (<20%) and high (≥20%) cardiovascular risk groups on risk predictions. Agreement in risk categorisation with different prediction models was compared using Cohen's kappa coefficient (κ). One hundred sixty-nine patients (females 130 (81.1%)) mean age 65±6.9years were studied. Of the participants, 80 (47.3%), 62 (36.7%), 18 (10.7%), 16 (9.5%), were predicted high risk by FRS BMI-based, FRS cholesterol-based, WHO/ISH without-cholesterol and WHO/ISH with-cholesterol models, respectively. Agreement between the two FRS models (κ=0.736, P<.0001) and the two WHO/ISH models (κ=0.804, P<.0001) in stratifying patients into high and low-risk groups, was "good." However, the agreements between FRS BMI-based and WHO/ISH without-cholesterol models (κ=0.234, P<.0001) and FRS cholesterol-based and WHO/ISH with-cholesterol models (κ=0.306, P<.0001) were only "fair." Cardiovascular risk predictions of FRS were higher than WHO/ISH charts and the agreement in risk stratification was not satisfactory in Sri Lankans. Therefore, different cardiovascular risk prediction models should not be used interchangeably in the follow-up of South Asians.