ASSIGN is a cardiovascular risk score. The name is derived from "ASSessing cardiovascular risk using SIGN" guidelines to ASSIGN preventive treatment.

The ASSIGN score was originally developed in 2006 by Professor Hugh Tunstall-Pedoe and Professor Mark Woodward of the University of Dundee, Scotland, working with the SIGN (Scottish Intercollegiate Guidelines Network) group on cardiovascular risk estimation.

ASSIGN was the first cardiovascular risk tool globally to incorporate social deprivation as a risk factor.

ASSIGN was originally developed and launched with SIGN guideline 97: Risk estimation and the prevention of cardiovascular disease. This was updated to SIGN 149 in 2017. ASSIGN has been used across NHS Scotland since its launch. An update of SIGN 149 is pending at the time of writing.

ASSIGN was recalibrated in 2023/4. The equation underwent a recentering and updating of baseline hazards, based on contemporary cohort studies, to reflect changing trends in population cardiovascular disease event rates since its initial development in 2006. This process did not change the coefficients for individual cardiovascular disease risk factors. The result of this update is the ASSIGN version (2.0) risk calculator which has now been approved for use.

ASSIGN score and risk threshold

The score is the estimated risk percent of developing CVD over ten years. So, ASSIGN 10 means a 10% risk. The key consideration is identifying those at high risk for targeted intervention and risk reduction.

A high score (10 or more) does not mean the individual will definitely have a myocardial infarction (MI), angina, or stroke. It does mean that their chances are higher than someone with a score below 10. Similarly, an ASSIGN score under 10 does not mean that they will never have an MI or stroke.

The threshold for treatment (internal link to Treatment and support page when it comes through) is now 10 rather than 20 as used in the original score,  to address future CVD risk in the current Scottish population.

The score should be applied within the context of the most recent relevant guidelines, and recommendations for the persons individual health needs and as part of a person-centred approach.

 

Importance of social deprivation

ASSIGN was the first cardiovascular risk tool globally to incorporate social deprivation as a risk factor.

The study published in Heart in 2006  showed a large gradient in coronary heart disease risk in Scottish men and women related to their socioeconomic status (defined by Scottish Index of Multiple Deprivation SIMD) but inadequately explained by conventional risk factors. Professors Tunstall-Pedoe and Woodward extended the study to cardiovascular disease as the endpoint, rather than just coronary heart disease.

ASSIGN versions have been updated over time using SIMD 2006, 2012 and 2020v2. The updated SIMD values have produced very little change to individual ASSIGN scores.

See Scottish Index of Multiple Deprivation (SIMD) reference for further information on SIMD.

Study populations

The original ASSIGN score was based on data from 13,000 Scottish men and women recruited 1984-95 who had their risk factors measured and were followed up until 2006 (Scottish Heart Health Extended Cohort -more information in 1997 cohort study).  ASSIGN 2.0 uses data from the UK Biobank Scottish population sub study and the Generation Scotland Scottish Family Study Health Cohort .

ASSIGN equation

The coefficients used in calculation of the ASSIGN score appear in the Appendix to the 2006 paper in Heart which describes the derivation of the score.

The updated equation in ASSIGN (2.0) uses the original  ASSIGN score beta coefficients and recentres the original equation using observations and updated baseline hazards  from the new derivation cohort:

gen lbarm3 = 0.05698*55.3999 + 0.2286*5.5488 - 0.53684*1.2944 + 0.01183*141.5754 + 0.81558*0.0481 + 0.275*0.5620 + 0.02005*2.0560 +  0.06296*1.4701 if sex==1

gen lbarf3 = 0.07203*55.1321 + 0.1272*5.8199 - 0.55836*1.6086 + 0.01064*135.2402 + 0.97727*0.0268 + 0.492*0.6129 + 0.02724*1.6107 +  0.09386*1.4740 if sex==0

gen menA2 = (asm-lbarm2)

gen femA2 = (asf-lbarf2)

gen menB2 = exp(menA2)

gen femB2 = exp(femA2)

gen menBexp2 = 100*(1-(0.9130^menB2))

gen femBexp2 = 100*(1-(0.9666^femB2))

egen assign3 = rowtotal (menBexp2 femBexp2)