External validation and clinical usefulness of three commonly used cardiovascular risk prediction scores in an Emirati population: a retrospective longitudinal cohort study

Unraveling the future productivity burden of cardiovascular disease in Qatar: Investigating the modifiable risk factors control in type 2 diabetes

Aims

Insufficient risk factor control can lead to a loss of millions of productivity-adjusted life years (PALYs). We aimed to assess the productivity burden of cardiovascular disease (CVD) in type 2 diabetes (T2D) and examine the potential advantages of enhancing the control of modifiable CVD risk factors in Qatar.

Materials and methods

Models were developed to quantify the productivity burden, in terms of PALYs, of CVD in Qataris with T2D, aged 40-65 years, from 2024 to 2033. The financial value of PALYs was determined based on the gross domestic product (GDP) per full-time worker (i.e. US$80,573). The base-case model estimated the productivity burden of CVD, and interventional scenarios were simulated to assess potential gains resulting from improved control of modifiable risk factors, including reduced incidence of T2D, lower systolic blood pressure (SBP), decreased number of smokers, and reduced total cholesterol. All costs and outcomes were discounted at an annual rate of 3 %.

Results

The base-case analysis projected that CVD in T2D would result in an estimated 2,096,536 PALYs (95 % confidence interval, 1,689,272-2,182,939), contributing US$225.46 (95 %CI, 1,689,272-2,182,939) billion to the country's GDP. However, implementing interventions to decrease the T2D incidence, lower SBP, reduce the number of smokers, and improve the total cholesterol could yield gains of 200,408, 198,173, 194,725, and 113,462 PALYs, respectively. These improvements would also lead to economic gains of US$20.01 billion, US$20.17 billion, US$19.78, and US$12.79 billion, respectively.

Conclusions

Implementing interventions that prioritize risk factor control and prevention of CVD can help enhance overall productivity in the country.

Discrimination and calibration performances of non-laboratory-based and laboratory-based cardiovascular risk predictions: a systematic review

BACKGROUND AND OBJECTIVE

This review compares non-laboratory-based and laboratory-based cardiovascular disease (CVD) risk prediction equations in populations targeted for primary prevention.

DESIGN

Systematic review.

METHODS

We searched five databases until 12 March 2024 and used prediction study risk of bias assessment tool to assess bias. Data on hazard ratios (HRs), discrimination (paired c-statistics) and calibration were extracted. Differences in c-statistics and HRs were analysed.

PROTOCOL

PROSPERO (CRD42021291936).

RESULTS

Nine studies (1 238 562 participants, 46 cohorts) identified six unique CVD risk equations. Laboratory predictors (eg, cholesterol and diabetes) had strong HRs, while body mass index in non-laboratory models showed limited effect. Median c-statistics were 0.74 for both models (IQR: lab 0.77-0.72; non-lab 0.76-0.70), with a median absolute difference of 0.01. Calibration measures between laboratory-based and non-laboratory-based equations were similar, although non-calibrated equations often overestimated risk.

CONCLUSION

The discrimination and calibration measures between laboratory-based and non-laboratory-based models show minimal differences, demonstrating the insensitivity of c-statistics and calibration metrics to the inclusion of additional predictors. However, in most reviewed studies, the HRs for these additional predictors were substantial, significantly altering predicted risk, particularly for individuals with higher or lower levels of these predictors compared with the average.

Societal health and economic burden of cardiovascular diseases in the population with type 2 diabetes in Qatar. A 10-year forecasting model

AIMS

To predict the future health and economic burden of cardiovascular disease (CVD) in type 2 diabetes (T2D) in Qatar.

MATERIALS AND METHODS

A dynamic multistate model was designed to simulate the progression of fatal and non-fatal CVD events among people with T2D in Qatar aged 40-79 years. First CVD events [i.e. myocardial infarction (MI) and stroke] were calculated via the 2013 Pooled Cohort Equation, while recurrent CVD events were sourced from the REACH registry. Key model outcomes were fatal and non-fatal MI and stroke, years of life lived, quality-adjusted life years, total direct medical costs and total productivity loss costs. Utility and cost model inputs were drawn from published sources. The model adopted a Qatari societal perspective. Sensitivity analyses were performed to test the robustness of estimates.

RESULTS

Over 10 years among people with T2D, model estimates 108 195 [95% uncertainty interval (UI) 104 249-112 172] non-fatal MIs, 62 366 (95% UI 60 283-65 520) non-fatal strokes and 14 612 (95% UI 14 472-14 744) CVD deaths. The T2D population accrued 4 786 605 (95% UI 4 743 454, 4 858 705) total years of life lived and 3 781 833 (95% UI 3 724 718-3 830 669) total quality-adjusted life years. Direct costs accounted for 57.85% of the total costs, with a projection of QAR41.60 billion (US$11.40 billion) [95% UI 7.53-147.40 billion (US$2.06-40.38 billion)], while the total indirect costs were expected to exceed QAR30.31 billion (US$8.30 billion) [95% UI 1.07-162.60 billion (US$292.05 million-44.55 billion)].

CONCLUSIONS

The findings suggest a significant economic and health burden of CVD among people with T2D in Qatar and highlight the need for more enhanced preventive strategies targeting this population group.

External validation of a cardiovascular risk model for Omani patients with type 2 diabetes mellitus: a retrospective cohort study

OBJECTIVES

To externally validate a recently developed cardiovascular disease (CVD) risk model for Omanis with type 2 diabetes mellitus (T2DM).

DESIGN

Retrospective cohort study.

SETTING

Nine primary care centres in Muscat Governorate, Oman.

PARTICIPANTS

A total of 809 male and female adult Omani patients with T2DM free of CVD at baseline were selected using a systematic random sampling strategy.

OUTCOME MEASURES

Data regarding CVD risk factors and outcomes were collected from the patients' electronic medical records between 29 August 2020 and 2 May 2021. The ability of the model to discriminate CVD risk was assessed by calculating the area under the curve (AUC) of the receiver-operating characteristic curve. Calibration of the model was evaluated using a Hosmer-Lemeshow χ2 test and the Brier score.

RESULTS

The incidence of CVD events over the 5-year follow-up period was 4.6%, with myocardial infarction being most frequent (48.6%), followed by peripheral arterial disease (27%) and non-fatal stroke (21.6%). A cut-off risk value of 11.8% demonstrated good sensitivity (67.6%) and specificity (66.5%). The area under the curve (AUC) was 0.7 (95% CI 0.60 to 0.78) and the Brier score was 0.01. However, the overall mean predicted risk was greater than the overall observed risk (11.8% vs 4.6%) and the calibration graph showed a relatively significant difference between predicted and observed risk levels in different subgroups.

CONCLUSIONS

Although the model slightly overestimated the CVD risk, it demonstrated good discrimination. Recalibration of the model is required, after which it has the potential to be applied to patients presenting to diabetic care centres elsewhere in Oman.

Effectiveness of China-PAR and Framingham risk score in assessment of 10-year cardiovascular disease risk in Chinese hypertensive patients

OBJECTIVES

Estimating the total risk of cardiovascular disease (CVD) using risk prediction models represents a huge improvement in identifying and treating each of the risk factors. The objective of this study was to evaluate the effectiveness of the China-PAR (Prediction of atherosclerotic CVD risk in China) and Framingham risk score (FRS) in predicting the 10-year risk of CVD in Chinese hypertensive patients. The results of the study can be used to design health promotion strategies.

STUDY DESIGN

A large cohort study was used to assess the validity of models by comparing model predictions with actual incidence rates.

METHODS

In total, 10,498 hypertensive patients aged 30-70 years in Jiangsu Province, China, participated in the baseline survey that took place between January and December 2010 and were followed up to May 2020. China-PAR and FRS were used to calculate the predicted 10-year risk of CVD. The 10-year observed incidence of new cardiovascular events was adjusted by the Kaplan-Meier method. The ratio of the predicted risk to the actual incidence was calculated to evaluate the effectiveness of the model. The discrimination Harrell's C statistics and calibration Chi-square value were used to evaluate the predictive reliability of the models.

RESULTS

Of the 10,498 participants, 4411 (42.02%) were male. During the mean follow-up of 8.30 ± 1.45 years, a total of 693 new cardiovascular events occurred. Both models overestimated the risk of morbidity to varying degrees, and the FRS overestimated to a greater extent. After adjustment for covariates, the results of Cox proportional hazards regression showed that the risk of CVD in the high-risk group was higher than in low-risk group. The degree of discrimination in both models was approximately 0.6, which showed that discrimination was not ideal in the models. In addition, Chi-square calibrations of the two models were <20 in males, which showed that calibration of the models was better for men than women.

CONCLUSIONS

The China-PAR and FRS models overestimated the risk of CVD for participants in this study. In addition, the degree of discrimination was not ideal, and both models performed better in males than in females in terms of calibration. The results of this study suggest that a more suitable risk prediction model should be established according to the characteristics of the hypertensive population in Jiangsu Province.

External validation of the ACC/AHA ASCVD risk score in a Colombian population cohort

No cardiovascular risk score has included Latin American patients in its development. The ACC/AHA ASCVD risk score has not been validated in Latin America; consequently, its predictive capacity in the population of the region is unknown. The aim of this study is to evaluate the discrimination capacity and calibration of the ACC/AHA ASCVD score to predict the 10-year risk of a cardiovascular event in a primary prevention cohort followed in a Colombian hospital. A retrospective cohort study was conducted in primary prevention patients belonging to an intermediate/high-risk and low-risk cohort without established atherosclerotic disease. Cardiovascular risk was calculated at inclusion. The calibration was analyzed by comparing observed and expected events in the different risk categories. A discrimination analysis was made using the area under the ROC curve and C statistic. A total of 918 patients were included-202 from the intermediate/high-risk and 716 from the low-risk cohort. The median cardiovascular risk was 3.6% (IQR 1.7-8.5%). At the 10-year follow-up, 40 events (4,4%) occurred. The area under the ROC curve was 0.782 (95% CI 0.71-0.85). The Hosmer-Lemeshow test did not show differences between expected and observed events. The ACC/AHA ASCVD score is calibrated and has good discrimination capacity in predicting 10-year risk of cardiovascular events in a Colombian population.

Development and validation of a novel 10-year cardiovascular risk prediction nomogram for the United Arab Emirates national population

OBJECTIVES

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of morbidity and mortality among United Arab Emirates (UAE) nationals. Recent studies have shown that current tools are poor in predicting the risk of incident ASCVD in Emiratis. To improve ASCVD risk prediction in this high-risk population, this study sought to develop and validate a novel and practical 10-year ASCVD risk nomogram using risk factors known to be significant in UAE nationals.

DESIGN

A 10-year retrospective cohort study.

SETTING

Outpatient clinics at a large public tertiary care hospital in Al-Ain, UAE.

PARTICIPANTS

Emiratis aged ≥18 years without prior cardiovascular disease (CVD) who had presented to Tawam Hospital's clinics between 1 April 2008 and 31 December 2008, were included. Patients' data were collected retrospectively until 31 January 2020.

EXPOSURE

Cox proportional hazards models were developed to estimate the 10-year ASCVD risk.

PRIMARY OUTCOME MEASURE

Model discrimination and calibration were assessed using the Harrell C-statistic and the Greenwood-Nam-D'Agostino (GND) χ² test, respectively. Receiver operating characteristic curve analysis was used to determine the optimal cut-off point of the nomogram for elevated ASCVD risk.

RESULTS

The study included 1245 patients, of whom 117 developed ASCVD within 10 years. The ASCVD risk nomogram comprised age, sex, family history of CVD, hypertension treatment, systolic blood pressure, total cholesterol, glycosylated haemoglobin A1c and estimated glomerular filtration rate. The Harrell C-statistic was 0.826 and the GND χ² was 2.83 (p=0.830), which indicated good discrimination and calibration of the nomogram model, respectively. The optimal cut-off point was determined to be 10% (sensitivity=79%; specificity=77%). The nomogram can be freely accessed as an online calculator at (https://ascvdriskuae.shinyapps.io/ASCVDrisk/).

CONCLUSIONS

The developed nomogram provides an accurate prognostic tool for 10-year ASCVD risk prediction in UAE nationals. These findings may help guide future research on CVD prevention in this high-risk population.

Distributions and burden of coronary calcium in asymptomatic Saudi patients referred to computed tomography

Background

Unlike Western and Asian populations, the prevalence and severity of coronary artery calcification (CAC) have not been adequately examined in Saudi Arabia and other nearby Arab Gulf countries.

Objectives

To estimate the age and gender specific percentiles of coronary calcium score (CCS) and to study the severity of CAC in relation to patient risk in a large sample of asymptomatic Saudi patients.

Methods

Retrospective cross-sectional study was conducted between July 2007 and December 2017 at a large Cardiac Centre in Riyadh, Saudi Arabia. The target was adult patients without pre-existing CAD referred to (64 multidetector spiral) computed tomography for standard indications.

Results

A total 2863 patients were included in the current analysis. The 90th percentile of CCS was 95.0 in males compared with 53.2 in females and was 823.95 in patients aged ≥ 75 years compared with zero in patients < 40 years. Extensive CAC (CCS > 400) were 3.1% in males compared with 1.6% in females and 14.0% in patients aged ≥ 75 years compared with 0.0% in patients < 40 years. CCS was steadily higher with increasing European systematic coronary risk evaluation; 3.1 ± 22.5 in mild risk, 37.1 ± 201.9 in moderate risk, 116.1 ± 256.1 in high risk, and 131.0 ± 222.0 in very high risk.

Conclusions

As expected, the findings confirm the higher burden of CAC in males, older age, and higher CAD risk. The burden of CAC in current patients is much lower than reported in US and other Western patients. Local cardiologist should consider using local rather than US percentiles of CCS.