Original and REGICOR Framingham functions in a nondiabetic population of a Spanish health care center: a validation study

Circulating Undercarboxylated Osteocalcin as Estimator of Cardiovascular and Type 2 Diabetes Risk in Metabolic Syndrome Patients

Undercarboxylated osteocalcin (ucOC) could be a biomarker of glucose disturbances and cardiovascular risk. Our study aimed to determine the association between serum levels of ucOC and cardiovascular risk in metabolic syndrome (MetS) patients and to analyse its potential role as estimator of type 2 diabetes (T2D) risk in this population. This cross-sectional study included 235 patients with MetS, 53.2% women, aged 55–75 years. Circulating ucOC levels were measured by ELISA. Cardiovascular risk was determined as Z-score of the diagnostic criteria for MetS (CV-ZS). Linear regression model was performed to analyse the association between circulating ucOC and CV-ZS. A receiver operating curve (ROC) was performed to analyse the usefulness of ucOC as T2D risk estimator. Patients above the CV-ZS median showed significant lower ucOC levels. We found an inverse association between ucOC levels and CV-ZS in MetS patients without T2D. Patients with ucOC levels below the 25^th percentile showed worse cardiometabolic profile and higher cardiovascular and T2D risk. The area under the curve performed better when ucOC levels were included along with the classic T2D risk factors. The measurement of circulating ucOC could be a useful tool to identify increased cardiovascular and T2D risk in MetS patients without T2D.

A framework for meta-analysis of prediction model studies with binary and time-to-event outcomes

It is widely recommended that any developed-diagnostic or prognostic-prediction model is externally validated in terms of its predictive performance measured by calibration and discrimination. When multiple validations have been performed, a systematic review followed by a formal meta-analysis helps to summarize overall performance across multiple settings, and reveals under which circumstances the model performs suboptimal (alternative poorer) and may need adjustment. We discuss how to undertake meta-analysis of the performance of prediction models with either a binary or a time-to-event outcome. We address how to deal with incomplete availability of study-specific results (performance estimates and their precision), and how to produce summary estimates of the c-statistic, the observed:expected ratio and the calibration slope. Furthermore, we discuss the implementation of frequentist and Bayesian meta-analysis methods, and propose novel empirically-based prior distributions to improve estimation of between-study heterogeneity in small samples. Finally, we illustrate all methods using two examples: meta-analysis of the predictive performance of EuroSCORE II and of the Framingham Risk Score. All examples and meta-analysis models have been implemented in our newly developed R package "metamisc".

Performance of the Framingham risk models and pooled cohort equations for predicting 10-year risk of cardiovascular disease: a systematic review and meta-analysis

BACKGROUND

The Framingham risk models and pooled cohort equations (PCE) are widely used and advocated in guidelines for predicting 10-year risk of developing coronary heart disease (CHD) and cardiovascular disease (CVD) in the general population. Over the past few decades, these models have been extensively validated within different populations, which provided mounting evidence that local tailoring is often necessary to obtain accurate predictions. The objective is to systematically review and summarize the predictive performance of three widely advocated cardiovascular risk prediction models (Framingham Wilson 1998, Framingham ATP III 2002 and PCE 2013) in men and women separately, to assess the generalizability of performance across different subgroups and geographical regions, and to determine sources of heterogeneity in the findings across studies.

METHODS

A search was performed in October 2017 to identify studies investigating the predictive performance of the aforementioned models. Studies were included if they externally validated one or more of the original models in the general population for the same outcome as the original model. We assessed risk of bias for each validation and extracted data on population characteristics and model performance. Performance estimates (observed versus expected (OE) ratio and c-statistic) were summarized using a random effects models and sources of heterogeneity were explored with meta-regression.

RESULTS

The search identified 1585 studies, of which 38 were included, describing a total of 112 external validations. Results indicate that, on average, all models overestimate the 10-year risk of CHD and CVD (pooled OE ratio ranged from 0.58 (95% CI 0.43-0.73; Wilson men) to 0.79 (95% CI 0.60-0.97; ATP III women)). Overestimation was most pronounced for high-risk individuals and European populations. Further, discriminative performance was better in women for all models. There was considerable heterogeneity in the c-statistic between studies, likely due to differences in population characteristics.

CONCLUSIONS

The Framingham Wilson, ATP III and PCE discriminate comparably well but all overestimate the risk of developing CVD, especially in higher risk populations. Because the extent of miscalibration substantially varied across settings, we highly recommend that researchers further explore reasons for overprediction and that the models be updated for specific populations.

Effects of a Novel Nutraceutical Combination (Aquilea Colesterol®) on the Lipid Profile and Inflammatory Biomarkers: A Randomized Control Trial

BACKGROUND

Cholesterol-lowering nutraceuticals are useful in the management of moderate hypercholesterolemia.

METHODS

In a parallel-group, randomized, placebo-controlled double-blind trial we evaluated the effects on plasma total cholesterol, low-density lipoprotein cholesterol (LDL-c), and inflammatory biomarkers of a nutraceutical combination (Aquilea Colesterol®) containing phytosterols (1.5 g), red yeast rice providing monacolin K (10 mg), hydroxytyrosol (5 mg), and plasma cholesterol values >5.17 mmol/L (>200 mg/dL) and LDL-c >2.97 mmol/L (>115 mg/dL). At baseline and at one and three months we recorded dietary habits; anthropometric parameters; blood pressure; lipid profile; fasting glucose; liver, renal, and muscle function tests, C-reactive protein (hs-CRP); and interleukin-6.

RESULTS

13 men and 27 women (mean age 61.8 years) completed the trial; 20 participants received the nutraceutical and 20 received placebo. No adverse effects were noted. Compared to placebo, at one and three months the nutraceutical reduced total cholesterol by 11.4% and 14.1%, LDL-c by 19.8% and 19.7%, and apolipoprotein B by 12.4% and 13.5%, respectively (p < 0.001; all). hs-CRP decreased significantly (p = 0.021) in the nutraceutical group.

CONCLUSION

The nutraceutical Aquilea Colesterol® is useful for reducing total cholesterol, LDL-c, and inflammation in individuals with moderate hypercholesterolemia.

Bariatric surgery versus conservative management for morbidly obese patients in Spain: a cost-effectiveness analysis

BACKGROUND

We assessed the cost-effectiveness of bariatric surgery (BS) versus conservative management (CM) for treating morbid obesity in Spain.

METHODS

We developed a probabilistic Markov model to estimate health outcomes, quality-adjusted life years (QALY), life years gained (LYG), and costs over lifetime and 10-year horizons. Combined common BS procedures were compared with CM. Clinical and utility inputs were obtained from the literature and resource use and costs from local sources (€2017).

RESULTS

Over the 10-year horizon, BS led to a cost increment of €9,386 and 1.6 additional QALY (€5,966/QALY). Leading to 0.6 LYG and 4.4 QALY gains and €300/patient average cost savings over lifetime, BS could potentially significantly reduce diabetes and cardiovascular disease risk over the considered horizons. Despite short-term cost reductions, surgery delay may lead to significant clinical benefits loss.

CONCLUSIONS

Compared to CM, BS is a more effective and less costly alternative for treating morbid obesity in Spain.

External validation of the 2008 Framingham cardiovascular risk equation for CHD and stroke events in a European population of middle-aged men. The PRIME study

OBJECTIVE

To test the applicability of the sex-specific 2008 Framingham general cardiovascular risk equation for coronary heart disease (CHD) and stroke in European middle-aged men from Ireland and France.

METHODS

In the PRIME study, 9638 healthy middle-aged men recruited in France and Ireland were surveyed for 10 years for the occurrence of first CHD and stroke events. The original Framingham equation, the partially calibrated Framingham equation (using the PRIME baseline survival at 10 years), and the completely calibrated Framingham equation (additionally using risk factor means calculated in PRIME) were assessed. Model fit (expected versus observed events) and discrimination ability were assessed using a modified Hosmer-Lemeshow Chi-square statistic and Harrell's c-index respectively.

RESULTS

The original (uncalibrated) Framingham equation overestimated by 1.94-fold the risk of CHD and stroke combined in PRIME, and by 2.23 and 1.42-fold in PRIME-France and PRIME-Ireland respectively. Adequate fit was found after complete calibration. However, discrimination ability of the Framingham equation was poor as shown by Harrell's c-index lower than 0.70.

CONCLUSION

The (completely) calibrated 2008 Framingham equation predicted accurate number of CHD and stroke events but discriminated poorly individuals at higher from those at lower event risk in a European population of middle-aged men.