Coronary disease risk prediction algorithm warranting incorporation of C-reactive protein in Turkish adults, manifesting sex difference

Risk estimation for the primary prevention of cardiovascular disease: considerations for appropriate risk prediction model selection

Cardiovascular diseases remain the number one cause of death globally. Cardiovascular disease risk scores are an integral tool in primary prevention, being used to identify individuals at the highest risk and guide the assignment of preventive interventions. Available risk scores differ substantially in terms of the population sample data sources used for their derivation and, consequently, in the absolute risks they assign to individuals. Differences in cardiovascular disease epidemiology between the populations contributing to the development of risk scores, and the target populations in which they are applied, can result in overestimation or underestimation of cardiovascular disease risks for individuals, and poorly informed clinical decisions. Given the wide plethora of cardiovascular disease risk scores available, identification of an appropriate risk score for a target population can be challenging. This Review provides an up-to-date overview of guideline-recommended cardiovascular disease risk scores from global, regional, and national contexts, evaluates their comparative characteristics and qualities, and provides guidance on selection of an appropriate risk score.

Prognostic Modelling Studies of Coronary Heart Disease—A Systematic Review of Conventional and Genetic Risk Factor Studies

This study aims to provide an overview of multivariable prognostic modelling studies developed for coronary heart disease (CHD) in the general population and to explore the optimal prognostic model by comparing the models’ performance. A systematic review was performed using Embase, PubMed, Cochrane, Web of Science, and Scopus databases until 30 November 2019. In this work, only prognostic studies describing conventional risk factors alone or a combination of conventional and genomic risk factors, being developmental and/or validation prognostic studies of a multivariable model, were included. A total of 4021 records were screened by titles and abstracts, and 72 articles were eligible. All the relevant studies were checked by comparing the discrimination, reclassification, and calibration measures. Most of the models were developed in the United States and Canada and targeted the general population. The models included a set of similar predictors, such as age, sex, smoking, cholesterol level, blood pressure, BMI, and diabetes mellitus. In this study, many articles were identified and screened for consistency and reliability using CHARM and GRIPS statements. However, the usefulness of most prognostic models was not demonstrated; only a limited number of these models supported clinical evidence. Unfortunately, substantial heterogeneity was recognized in the definition and outcome of CHD events. The inclusion of genetic risk scores in addition to conventional risk factors might help in predicting the incidence of CHDs; however, the generalizability of the existing prognostic models remains open. Validation studies for the existing developmental models are needed to ensure generalizability, improve the research quality, and increase the transparency of the study.

Validation and comparison of 28 risk prediction models for coronary artery disease

AIMS

Risk prediction models (RPMs) for coronary artery disease (CAD), using variables to calculate CAD risk, are potentially valuable tools in prevention strategies. However, their use in the clinical practice is limited by a lack of poor model description, external validation, and head-to-head comparisons.

METHODS AND RESULTS

CAD RPMs were identified through Tufts PACE CPM Registry and a systematic PubMed search. Every RPM was externally validated in the three cohorts (the UK Biobank, LifeLines, and PREVEND studies) for the primary endpoint myocardial infarction (MI) and secondary endpoint CAD, consisting of MI, percutaneous coronary intervention, and coronary artery bypass grafting. Model discrimination (C-index), calibration (intercept and regression slope), and accuracy (Brier score) were assessed and compared head-to-head between RPMs. Linear regression analysis was performed to evaluate predictive factors to estimate calibration ability of an RPM. Eleven articles containing 28 CAD RPMs were included. No single best-performing RPM could be identified across all cohorts and outcomes. Most RPMs yielded fair discrimination ability: mean C-index of RPMs was 0.706 ± 0.049, 0.778 ± 0.097, and 0.729 ± 0.074 (P < 0.01) for prediction of MI in UK Biobank, LifeLines, and PREVEND, respectively. Endpoint incidence in the original development cohorts was identified as a significant predictor for external validation performance.

CONCLUSION

Performance of CAD RPMs was comparable upon validation in three large cohorts, based on which no specific RPM can be recommended for predicting CAD risk.

PARS risk charts: A 10-year study of risk assessment for cardiovascular diseases in Eastern Mediterranean Region

This study was designed to develop a risk assessment chart for the clinical management and prevention of the risk of cardiovascular disease (CVD) in Iranian population, which is vital for developing national prevention programs. The Isfahan Cohort Study (ICS) is a population-based prospective study of 6504 Iranian adults ≥35 years old, followed-up for ten years, from 2001 to 2010. Behavioral and cardiometabolic risk factors were examined every five years, while biennial follow-ups for the occurrence of the events was performed by phone calls or by verbal autopsy. Among these participants, 5432 (2784 women, 51.3%) were CVD free at baseline examination and had at least one follow-up. Cox proportional hazard regression was used to predict the risk of ischemic CVD events, including sudden cardiac death due to unstable angina, myocardial infarction, and stroke. The model fit statistics such as area under the receiver-operating characteristic (AUROC), calibration chi-square and the overall bias were used to assess the model performance. We also tested the Framingham model for comparison. Seven hundred and five CVD events occurred during 49452.8 person-years of follow-up. The event probabilities were calculated and presented color-coded on each gender-specific PARS chart. The AUROC and Harrell's C indices were 0.74 (95% CI, 0.72-0.76) and 0.73, respectively. In the calibration, the Nam-D'Agostino χ2 was 10.82 (p = 0.29). The overall bias of the proposed model was 95.60%. PARS model was also internally validated using cross-validation. The Android app and the Web-based risk assessment tool were also developed as to have an impact on public health. In comparison, the refitted and recalibrated Framingham models, estimated the CVD incidence with the overall bias of 149.60% and 128.23% for men, and 222.70% and 176.07% for women, respectively. In conclusion, the PARS risk assessment chart is a simple, accurate, and well-calibrated tool for predicting a 10-year risk of CVD occurrence in Iranian population and can be used in an attempt to develop national guidelines for the CVD management.

Algorithm for predicting CHD death risk in Turkish adults: conventional factors contribute only moderately in women

OBJECTIVE

To assist the management strategy of individuals, we determined an algorithm for predicting the risk of coronary heart disease (CHD) death in Turkish adults with a high prevalence of metabolic syndrome (MetS).

METHODS

The risk of CHD death was estimated in 3054 middle-aged adults, followed over 9.08±4.2 years. Cox proportional hazard regression was used to predict risk. Discrimination was assessed using C-statistics.

RESULTS

CHD death was identified in 233 subjects. In multivariable analysis, the serum high-density lipoprotein-cholesterol (HDL-C) level was not predictive in men and the non-HDL-C level was not predictive in women. Age, presence of diabetes, systolic blood pressure ≥160 mm Hg, smoking habit, and low physical activity were predictors in both sexes. The exclusion of coronary disease at baseline did not change the risk estimates materially. Using an algorithm of the 7 stated variables, individuals in the highest category of risk score showed a 19- to 50-fold higher spread in the absolute risk of death from CHD than those in the second lowest category. C-index of the model using age alone was as high as 0.774 in men and 0.836 in women (p<0.001 each), while the incorporation of 6 conventional risk factors contributed to a C-index of 0.058 in males and 0.042 in females.

CONCLUSION

In a middle-aged population with prevalent MetS, men disclosed anticipated risk parameters (except for high HDL-C levels) as determinants of the risk of CHD death. On the other hand, serum non-HDL-C levels and moderate systolic hypertension were not relevant in women. The moderate contribution of conventional risk factors (beyond age) to the estimation of the risk of CHD death in women is consistent with the operation of autoimmune activation.

Little contribution of conventional factors in an algorithm to predicting death risk in Turkish adults

OBJECTIVE

Determinants of risk of death are highly relevant for the management strategy of individuals. We aimed to determine an algorithm for predicting risk of death in Turkish adults who have a high prevalence of metabolic syndrome (MetS).

METHODS

Nine-year risk of death was estimated in 3348 middle-aged adults, followed over 8.81±4.2years. Cox proportional hazard regression was used to predict risk of death. Discrimination was assessed using C-statistics.

RESULTS

Death occurred in 565 subjects. In multivariable analysis, high-density lipoprotein (HDL) and non-HDL cholesterol levels were not predictive in either sex; in women, current smoking was also not predictive. Age, presence of diabetes, systolic blood pressure ≥160mmHg and low physical activity were predictors in both sexes, beyond smoking status in men. Exclusion of coronary disease at baseline did not change risk estimates materially. Using an algorithm of the stated 7 variables showed an 11- to 18-fold spread in the absolute risk of dying among individuals in the highest than in the lowest of 4 risk score categories. C-statistics of the model using age alone was 0.790 in men, 0.808 in women (p<0.001 each), while the incorporation of 6 conventional risk factors contributed to C-index was >0.020 in males and 0.009 in females.

CONCLUSIONS

In a middle-aged population with prevalent MetS, serum lipoproteins and, in women, smoking status, were not relevant for the risk of death. The contribution of conventional risk factors beyond age to estimating risk of death was modest among Turkish men, and little in women in whom autoimmune activation is operative.

Associations of high sensitivity C-reactive protein levels in schizophrenia and comparison groups

Schizophrenia is characterized by physical (mainly metabolic and cardiovascular) comorbidity and shortened lifespan. High sensitivity C-reactive protein (hs-CRP), an inflammatory marker of hepatic origin linked to metabolic and cardiovascular diseases and mortality in the general population, has been reported to be elevated in people with schizophrenia. However, the relationship of hs-CRP to psychiatric and medical risk factors, after controlling for potentially confounding variables such as smoking, is not well established in schizophrenia. We assessed hs-CRP levels along with various demographic, psychiatric, and metabolic measures in 88 clinically stable outpatients with schizophrenia or schizoaffective disorder and 71 age epoch-matched comparison subjects with no history of a major psychiatric illness. hs-CRP levels were significantly higher in individuals with schizophrenia than in comparison subjects. Higher hs-CRP levels in the schizophrenia group were associated with female gender, more severe negative symptoms, greater medical comorbidity, and worse metabolic risk factors including BMI, fasting glucose, and hemoglobin A1c levels. hs-CRP was not related to age, race, education, smoking status, antipsychotic dosage, or cognitive impairment. Longitudinal studies are needed to investigate the relationship between hs-CRP and long-term health outcomes including metabolic syndrome, cardiovascular disease, and mortality in schizophrenia.

Cardiovascular risk assessment: a global perspective

An important strategy in primary prevention of cardiovascular diseases (CVD) is the early identification of high-risk individuals. Effective implementation of a strategy to identify these individuals in a clinical setting is reliant on the availability of appropriate CVD risk-assessment models and guideline recommendations. Several well-known models for CVD risk assessment have been developed and utilized in the USA and Europe, but might not be suitable for use in other regions or countries. Very few reports have discussed the development of risk-assessment models and recommendations from a global perspective. In this Review, we discuss why risk-assessment methods developed from studies in one geographical region or ethnic population might not be suitable for other regions or populations, and examine the availability and characteristics of predictive models in areas beyond the USA or Europe. In addition, we compare the differences in risk-assessment recommendations outlined in CVD clinical guidelines from developed and developing countries, and consider their potential effect on clinical practice. This overview of cardiovascular risk assessment from a global perspective can potentially guide low-to-middle-income countries in the development or validation of their own CVD risk-assessment models, and the formulation of recommendations in their own clinical guidelines according to local requirements.

Type-2 diabetes and coronary heart disease: common physiopathology, viewed from autoimmunity

Two highly prevalent diseases, Type-2 diabetes mellitus and coronary heart disease (CHD), share risk factors. Excess levels of LDL-cholesterol have been overemphasized to uniformly encompass the development of CHD, and the origin of insulin resistance underlying Type-2 diabetes has not been fully elucidated. Autoimmune response has been recognized to be responsible only of a small minority of diabetes. The increasing trend in the worldwide prevalence of diabetes and the risk factors for both diseases are reviewed, the independent mediation for CHD of (central) adiposity in both diseases and the 'hypertriglyceridemic waist' phenotype are outlined. Evidence is described that serum lipoprotein (Lp)(a) concentrations, not only in excess, but also in apparently 'reduced' levels, as a result of autoimmune response, underlie both disorders and are closely related to insulin resistance.

The incidence of coronary heart disease and the population attributable fraction of its risk factors in Tehran: a 10-year population-based cohort study

BACKGROUND

Data on incidence of coronary heart disease (CHD) is scarce in the Middle East and little is known about the contribution of known risk factors in this area.

METHODS

The incidence of CHD and the effect of modifiable risk factors were explored in 2889 men and 3803 women aged 30-74 years in the population based cohort of the Tehran Lipid and Glucose Study, during 1999-2010. Average population attributable fraction (aPAF) was calculated for any risk factor using direct method based on regression model.

RESULTS

The crude incidence rate in men was about twice that in women (11.9 vs. 6.5 per 1000 person-years). The aPAF of hypertension, diabetes, high total cholesterol and low-HDL cholesterol was 9.4%, 6.7%, 7.3% and 6.1% in men and 17%, 16.6%, 12% and 4.6% in women respectively. This index was 7.0% for smoking in men. High risk age contributed to 42% and 22% of risk in men and women respectively.

CONCLUSIONS

The incidence in this population of Iran was comparable to those in the US in the seventies. Well known modifiable risk factors explained about 40% and 50% of CHD burden in men and women respectively. Aging, as a reflection of unmeasured or unknown risk factors, bears the most burden of CHD, especially in men; indicating more age-related health care is required.