ABC | Volume 113, Nº4, October 2019

Updated Updated Cardiovascular Prevention Guideline of the Brazilian Society Of Cardiology – 2019 Arq Bras Cardiol. 2019; 113(4):787-891 most of them have proven to be fruitless, as these groups are at high risk for CAD. Revascularization strategies guided by myocardial perfusion scintigraphy or coronary computed tomography angiography in asymptomatic diabetic individuals were not superior to clinical management, based only on traditional risk factors. In the study FACTOR-64 – a randomized clinical trial with 900 patients with DM1 or DM2 for at least three years and without CAD symptoms –, the revascularization strategy guided by coronary computed tomography angiography did not reduce the risk for acute coronary syndrome (ACS) or CV mortality. 81 Similarly, in the studies DIAD 82 and DYNAMIT, 83 the revascularization strategy guided by exercise stress test with scintigraphy did not improve CV and non-CV outcomes compared to conventional medical treatment in 1,900 asymptomatic diabetic patients. Currently, the more efficient and practical resources to determine CV risk in diabetic patients have been the isolated control of its risk factors. Subanalyses of the Diabetes Heart Study 84 and FACTOR-64 81 revealed that the factors with greater predictive power for ACS risk were the use of statins and LDL-c levels, followed by glomerular filtration rate, microalbuminuria, and C-reactive protein (CRP). The treatment of CV risk factors related to aggressive diabetes is the method more strongly associated with the reduction in CV morbidity and ACS mortality in diabetic patients, as demonstrated in the study STENO-2. 77 However, as detailed below, the most effective way of predicting risk and managing more or less intensive targets in primary prevention should be combining risk and coronary calcium scores. 3.2.4. Risk Calculator Risk scores are among the most commonly used strategies, consisting of estimating risk based on prospective data collected from cohorts of diabetic patients, such as the UKPDS, the DECODE, the DARTS, the ADVANCE, the Swedish National Diabetes Register, and the DCS. 85,86 Other calculators developed for mixed populations (diabetics and non-diabetics) are also widely used: ORS/SBC, Framingham, Pooled Cohort Equations (ASCVD), REYNOLDS, SCORE, PROCAM, and others. 74 The main advantage of these methods lies in their easy application in clinical practice, as they consider the usual clinical data, such as age, laboratory test values, and anthropometric information. The UKPDS calculator is more recommended for diabetic patients (IDF21 guidelines, NICE, Canadian Diabetes Association, Australian National Vascular Disease Prevention Alliance, and others) and the ORS is the more widely used in the Brazilian diabetic and non-diabetic population. Nevertheless, these and other strategies to estimate the progression of vascular diseases are still limited, underestimating the risk in young patients with DM or recently diagnosed patients, while overestimating the risk in individuals diagnosed for > 10 years or with HbA1c > 9.0%. 87-89 Also, the scores do not take into account the advances of the last 5 to 10 years, such as new drugs and diagnostic methods, and have relatively low predictive performance (C-statistic between 0.54–0.70), considering that 30 to 60% of individuals are at moderate risk. 87 In this scenario, adding the coronary calcium score to clinical risks has become the most efficient and cost-effective alternative to estimate the CAD risk in patients at moderate risk. 3.2.5. Coronary Artery Calcium Score Coronary artery calcium (CAC) is a highly specific characteristic of coronary atherosclerosis. The CAC score (CACS) is an available, consistent, and reproducible method to evaluate the risk for future coronary events, essentially by guiding primary prevention strategies. 90 CACS in asymptomatic populations is cost-effective for moderate risk patients 90 and has a positive impact on adherence to treatment. 91 The Multi-Ethnic Study of Atherosclerosis (MESA) developed a valuable and useful support tool for CACS to predict risk, incorporating CACS to a clinical model using 10-year follow-up data until the first manifestation of CAD. 92 The MESA score involves individuals aged 45 to 85 years, providing CAD risk in 10 years with and without CACS. The Heinz Nixdorf Recall (HNR) and the Dallas Heart Study validated the score. 92 The greatest limitation of the MESA score is that its algorithm does not include all forms of atherosclerotic disease, which differentiates it from the ORS/SBC. 93 In an analysis of patients from the MESA study 94 who had an estimate of atherosclerotic cardiovascular disease (ASCVD) of 5 to 7.5% in 10 years, a CACS = 0 was associated with an ASCVD observed rate of 1.5%, while any calcium score > 0 was associated with an actual rate of events of at least 7.5%. In individuals from MESA with an ASCVD risk between 7.5 and 20%, a CACS = 0 was associated with an event rate of around 4.5%, while a CACS > 0 was associated with a net benefit of statin therapy of approximately 10.5%. CACS should represent a way of segregating diabetic individuals with a higher atherosclerotic burden and possibly those suffering for longer the vascular effects of insulin resistance associated with endotheliopathy, which begins in the early stages of pre-diabetes. 72 As explained above, pathophysiologically, vascular disease, especially diabetic coronary disease, starts long before its clinical diagnosis. However, the strategies to map the progression of the vascular disease in earlier stages are still limited, and there are few viable tools for clinical practice. Thus, a clinical score – such as the ORS/SBC – combined with CACS is the most efficient way to predict the CAD risk in moderate-risk patients. 3.2.6. Lipid Targets in Primary Prevention for Individuals with Metabolic Syndrome and Diabetes Mellitus Statins are among the most prescribed drugs worldwide, reflecting their fundamental role in primary and secondary prevention of atherosclerotic disease and the high prevalence of dyslipidemias. Several randomized clinical trials (RCT) and meta-analyses, such as the Cholesterol Treatment Trialists’ (CTT) Collaboration, 14 solidified the indication of statins. Among 21 RCT comparing statin and 808