Ferran Cordón

Estimación del riesgo coronario en España mediante la ecuación de Framingham calibrada

Rev Esp Cardiol 2003;56(3):253-61 253 Introducción y objetivos. Las ecuaciones de Framingham sobrestiman el riesgo de enfermedad coronaria en los países cuya incidencia es baja. En éstos, la ecuación debería adaptarse para la correcta prevención de la enfermedad coronaria. Se presentan las tablas de riesgo coronario global de Framingham calibradas para la población española. Pacientes y método. Se utilizó el procedimiento de calibración de la ecuación de Framingham, consistente en sustituir la prevalencia de factores de riesgo cardiovascular y la tasa de incidencia de acontecimientos coronarios de Framingham por las de nuestro medio. Se ha usado la ecuación de Framingham, que incluye el colesterol unido a lipoproteínas de alta densidad (cHDL). Se han calculado las probabilidades de acontecimiento a los 10 años y se han elaborado unas tablas con códigos de color y la probabilidad exacta en cada casilla correspondiente a las distintas combinaciones de los factores de riesgo clásicos, para una concentración de cHDL de 35-59 mg/dl. Resultados. Las tasas de acontecimientos coronarios y la prevalencia de factores de riesgo difieren considerablemente entre la población estudiada y Framingham. Valores de cHDL < 35 mg/dl incrementan el riesgo en un 50% y los > 60 mg/dl lo reducen en un 50%, aproximadamente. La proporción de casillas con una probabilidad de acontecimiento coronario a los 10 años superior al 9% es 2,3 veces menor, y la de casillas con una probabilidad > 19% es 13 veces menor en las tablas calibradas que en las originales de Framingham. Conclusiones. La función de Framingham calibrada puede constituir un instrumento para estimar con más precisión el riesgo coronario global en la prevención primaria de esta enfermedad en España. Su uso debe acompañarse de una validación apropiada y se debe trabajar en la elaboración de ecuaciones propias españolas.

An adaptation of the Framingham coronary heart disease risk function to European Mediterranean areas

Aim: To determine whether the Framingham function accurately predicts the 10 year risk of coronary disease and to adapt this predictive method to the characteristics of a Spanish population. Method and Results: A Framingham function for predicting 10 year coronary deaths and non-fatal myocardial infarction was applied to the population of the province of Gerona, Spain, where the cumulated incidence rate of myocardial infarction has been determined since 1988 by a specific registry. The prevalence of cardiovascular risk factors in this region of Spain was established in 1995 by a cross sectional study on a representative sample of 1748 people. The number of cases estimated by the Framingham function for 10 year coronary deaths and non-fatal myocardial infarction was compared with that observed. The Framingham function estimated 2425 coronary heart disease cases in women and 1181 were observed. In men, 9919 were estimated and 3706 were observed. Recalibrating the Framingham equations to the event rate and the prevalence of the risk factors in Gerona led to estimates very close to the number of cases observed in Gerona men and women. Conclusions: The Framingham function estimates more than doubled the actual risk of coronary disease observed in north east Spain. After calibration, the Framingham function became an effective method of estimating the risk in this region with low coronary heart disease incidence.

Validity of an adaptation of the Framingham cardiovascular risk function: the VERIFICA study

Background: To assess the reliability and accuracy of the Framingham coronary heart disease (CHD) risk function adapted by the Registre Gironí del Cor (REGICOR) investigators in Spain. Methods: A 5-year follow-up study was completed in 5732 participants aged 35–74 years. The adaptation consisted of using in the function the average population risk factor prevalence and the cumulative incidence observed in Spain instead of those from Framingham in a Cox proportional hazards model. Reliability and accuracy in estimating the observed cumulative incidence were tested with the area under the curve comparison and goodness-of-fit test, respectively. Results: The Kaplan–Meier CHD cumulative incidence during the follow-up was 4.0% in men and 1.7% in women. The original Framingham function and the REGICOR adapted estimates were 10.4% and 4.8%, and 3.6% and 2.0%, respectively. The REGICOR-adapted function’s estimate did not differ from the observed cumulated incidence (goodness of fit in men, p = 0.078, in women, p = 0.256), whereas all the original Framingham function estimates differed significantly (p<0.001). Reliabilities of the original Framingham function and of the best Cox model fit with the study data were similar in men (area under the receiver operator characteristic curve 0.68 and 0.69, respectively, p = 0.273), whereas the best Cox model fitted better in women (0.73 and 0.81, respectively, p<0.001). Conclusion: The Framingham function adapted to local population characteristics accurately and reliably predicted the 5-year CHD risk for patients aged 35–74 years, in contrast with the original function, which consistently overestimated the actual risk.

Trends in cardiovascular risk factor prevalence (1995-2000-2005) in northeastern Spain

Background High prevalence of cardiovascular risk factors has been observed in Spain along with low incidence of acute myocardial infarction. Our objective was to determine the trends of cardiovascular risk factor prevalence between 1995 and 2005 in the 35-74-year-old population of Gerona, Spain. Design Comparison of cross-sectional studies were conducted in random population samples in 1995, 2000, and 2005 at Gerona, Spain. Methods An electrocardiogram was obtained, along with standardized measurements of body mass index, lipid profile, systolic and diastolic blood pressure, glycaemia, energy expenditure in physical activity, smoking, use of lipid-lowering and antihypertensive medications, and cardiovascular risk. Prevalence of diabetes, hypertension, and obesity was calculated and standardized for age. Results A total of 7571 individuals (52.0% women) were included (response rate 72%). Low-density lipoprotein cholesterol > 3.4 mmol/l (130 mg/dl) (49.7%) and hypertension (39.1%) were the most prevalent cardiovascular risk factors. In 1995, 2000 and 2005, low-density lipoprotein cholesterol decreased in both men and women: 4.05-3.913.55 mmol/l (156-151-137 mg/dl) and 3.84-3.81-3.40 mmol/l (148-147-131 mg/dl), respectively. Increases were observed in lipid-lowering drug use (5.7-6.3-9.6% in men and 4.0-5.8-8.0% in women), controlled hypertension (14.8-35.4-37.7% in men and 21.3-36.9-45.0% in women); (all P-trends < 0.01), and obesity (greatest for men: 17.5-26.0-22.7%, P-trends = 0.020). Prevalence of myocardial infarction or possibly abnormal Q waves in electrocardiogram also increased significantly (3.9-4.7-6.4%, P-trends = 0.018). Conclusions The cardiovascular risk factor prevalence change in Gerona was marked in this decade by a shift of total cholesterol and low-density lipoprotein cholesterol distributions to the left, independent of the increase in lipid-lowering drug use, and better hypertension control with increased use of antihypertensive drugs. Eur J Cardiovasc Prev Rehabil 14:653-659

Prevalence of Symptomatic and Asymptomatic Peripheral Arterial Disease and the Value of the Ankle-brachial Index to Stratify Cardiovascular Risk

OBJECTIVES To determine the prevalence of ankle-brachial index (ABI)<0.9 and symptomatic peripheral arterial disease (PAD), association with cardiovascular risk factors (CVRF), and impact of adding ABI measurement to coronary heart disease (CHD) risk screening. DESIGN Population-based cross-sectional survey of 6262 participants aged 35-79 in Girona, Spain. METHODS Standardized measurements (CVRF, ABI, 10-year CHD risk) and history of intermittent claudication (IC), CHD, and stroke were recorded. ABI<0.9 was considered equivalent to moderate-to-high CHD risk (> or =10%). RESULTS ABI<0.9 prevalence was 4.5%. Only 0.62% presented low ABI and IC. Age, current smoker, cardiovascular disease, and uncontrolled hypertension independently associated with ABI<0.9 in both sexes; IC was also associated in men and diabetes in women. Among participants 35-74 free of cardiovascular disease, 6.1% showed moderate-to-high 10-year CHD risk; adding ABI measurement yielded 8.7%. Conversely, the risk function identified 16.8% of these participants as having 10-year CHD risk>10%. In participants 75-79 free of cardiovascular disease, the prevalence of ABI<0.9 (i.e., CHD risk> or =10%) was 11.9%. CONCLUSIONS ABI<0.9 is relatively frequent in those 35-79, particularly over 74. However, IC and CHD risk> or =10% indicators are often missing. Adding ABI measurement to CHD-risk screening better identifies moderate-to-high cardiovascular risk patients.

Comparación de la función de Framingham original y la calibrada del REGICOR en la predicción del riesgo coronario poblacional

Fundamento y objetivo: Se desconocen las implicaciones terapeuticas derivadas del uso de la funcion de riesgo coronario de Framingham calibrada por los investigadores de los estudios REGICOR y Framingham (Framingham-REGICOR) para la poblacion espanola. El objetivo de este estudio fue determinar las diferencias en la clasificacion del riesgo de la poblacion de 35 a 74 anos usando la funcion de Framingham clasica (Framingham-Wilson) y la calibrada y sus consecuencias en la indicacion de tratamiento hipolipemiante con las guias de practica clinica. Pacientes y metodo: Se comparo la clasificacion en las categorias de riesgo a 10 anos de = 40% observada mediante ambas funciones en 3.270 individuos de entre 35 y 74 anos sin antecedentes de cardiopatia isquemica ni tratamiento hipolipemiante, provenientes de 2 muestras poblacionales representativas de la provincia de Girona, reclutadas entre 1994 y 2001. Se calculo el numero de candidatos a tratamiento hipolipemiante segun las guias vigentes de practica clinica y las 2 funciones. Resultados: Un 5,9% del total de la muestra recibia tratamiento hipolipemiante en el momento del examen. La funcion Framingham-REGICOR asigno al 54,2% de las mujeres y al 67,9% de los varones no diabeticos a una categoria de riesgo inferior que la funcion Framingham-Wilson. El 0,2% de las mujeres y el 21,2% de los varones descendieron dos categorias. Un 75,7% de los participantes diabeticos descendio una categoria y el 18,5% descendio dos. Con las guias europeas de 2003 recibirian hipolipemiantes el 14,5 y el 4,4% de participantes no diabeticos usando las funciones de Framingham-Wilson y Framingham-REGICOR, respectivamente. Conclusiones: La funcion calibrada de Framingham-REGICOR adjudica una categoria de riesgo coronario menor que la de Framingham original en mas del 50% de mujeres y casi el 90% de varones. Es una herramienta mas recomendable que esta en la prevencion primaria de la enfermedad coronaria en Espana.

Rendimiento de la estimación del riesgo cardiovascular en España mediante la utilización de distintas funciones

Introduccion y objetivos A pesar de que presentan una baja incidencia, las enfermedades cardiovasculares son la causa mas frecuente de morbimortalidad en Espana. Se dispone de diversas funciones para calcular el riesgo cardiovascular en la prevencion primaria, cuya capacidad para identificar a los pacientes que desarrollaran acontecimientos cardiovasculares es poco conocida. Comparamos el rendimiento de las funciones de Framingham original, adaptada de REGICOR (Registre Gironi del Cor) y SCORE (Systematic COronary Risk Evaluation) para paises de bajo riesgo. Metodos Se registraron todos los acontecimientos cardiovasculares en un seguimiento de 5 anos de una cohorte sin enfermedad coronaria en 9 comunidades autonomas. Se midieron los factores de riesgo cardiovascular entre 1995 y 1998. Se considero que el riesgo era elevado a los 10 anos en ≥ 20% para Framingham, ≥ 10, ≥ 15 y ≥ 20% para REGICOR y ≥ 5% para SCORE. Resultados Se produjeron 180 (3,1%) acontecimientos coronarios (112 en varones y 68 en mujeres) en las 5.732 personas (57,3% de mujeres) en las que se realizo el seguimiento. Se produjo muerte cerebrovascular en 43 personas, asi como 24 acontecimientos vasculares no coronarios. Con la funcion REGICOR se obtuvo el mayor valor predictivo positivo para enfermedad coronaria y cardiovascular a cualquier edad, y, tomando un limite de 10% de riesgo a los 10 anos, se clasifico a menos poblacion de alto riesgo de 35-74 anos (12,4%) que con la funcion de Framingham (22,4%). SCORE y Framingham clasificaron al 8,4 y al 16,6% de la poblacion de 35-64 anos como de alto riesgo cardiovascular y REGICOR, al 7,5%. Conclusiones La funcion adaptada de REGICOR es la opcion aplicable hasta los 74 anos que muestra el mejor equilibrio en la capacidad de clasificacion de riesgo de acontecimientos cardiovasculares. Su aplicacion permite la clasificacion de alto riesgo a individuos con un perfil mas adecuado para ser candidatos a tratamiento hipolipemiante.

Why should population attributable fractions be periodically recalculated? An example from cardiovascular risk estimation in southern Europe.

OBJECTIVE To determine the effect of age and study period on coronary heart disease (CHD) risk attributable to cardiovascular risk factors. METHODS A cohort of cardiovascular disease (CVD)-free randomly participants from Girona (Spain) aged 35-74 years recruited in 1995 and 2000 and followed for an average of 6.9 years. A survey conducted in the same area in 2005 was also used for the analysis. Smoking, hypertension, diabetes, sedentary lifestyle, obesity, total cholesterol > or = 240 mg/dl, low-density lipoprotein (LDL) cholesterol > or = 160 mg/dl, and high-density lipoprotein cholesterol <40 mg/dl were the risk factors considered. The composite end-point included myocardial infarction, angina pectoris, and CHD death. RESULTS LDL cholesterol had the highest potential for CHD prevention between 35 and 74 years [42% (95% Confidence Interval: 23,58)]. The age-stratified analysis showed that the population attributable risk (PAF) for smoking was 64% (30,80) in subjects < 55 years; for those > or = 55 years, the PAF for hypertension was 34% (1,61). The decrease observed between 1995 and 2005 in the populations mean LDL cholesterol level reduced that PAF in all age groups. CONCLUSION Overall, LDL cholesterol levels had the highest potential for CHD prevention. Periodic PAF recalculation in different age groups may be required to adequately monitor population trends.

Derivation and validation of REASON: A risk score identifying candidates to screen for peripheral arterial disease using ankle brachial index

BACKGROUND The recommendation of screening with ankle brachial index (ABI) in asymptomatic individuals is controversial. The aims of the present study were to develop and validate a pre-screening test to select candidates for ABI measurement in the Spanish population 50-79 years old, and to compare its predictive capacity to current Inter-Society Consensus (ISC) screening criteria. METHODS AND RESULTS Two population-based cross-sectional studies were used to develop (n = 4046) and validate (n = 3285) a regression model to predict ABI < 0.9. The validation dataset was also used to compare the models predictive capacity to that of ISC screening criteria. The best model to predict ABI < 0.9 included age, sex, smoking, pulse pressure and diabetes. Assessment of discrimination and calibration in the validation dataset demonstrated a good fit (AUC: 0.76 [95% CI 0.73-0.79] and Hosmer-Lemeshow test: χ(2): 10.73 (df = 6), p-value = 0.097). Predictions (probability cut-off value of 4.1) presented better specificity and positive likelihood ratio than the ABI screening criteria of the ISC guidelines, and similar sensitivity. This resulted in fewer patients screened per diagnosis of ABI < 0.9 (10.6 vs. 8.75) and a lower proportion of the population aged 50-79 years candidate to ABI screening (63.3% vs. 55.0%). CONCLUSION This model provides accurate ABI < 0.9 risk estimates for ages 50-79, with a better predictive capacity than that of ISC criteria. Its use could reduce possible harms and unnecessary work-ups of ABI screening as a risk stratification strategy in primary prevention of peripheral vascular disease.

Estimating Cardiovascular Risk in Spain Using Different Algorithms

INTRODUCTION AND OBJECTIVES Although its incidence is low, cardiovascular disease is the most common cause of morbidity and mortality in Spain. A number of different algorithms can be used to calculate cardiovascular disease risk for primary prevention, but their ability to identify patients who will experience a cardiovascular event is not well understood. The objective of this study was to compare the results of using the original Framingham algorithm and two adaptations for low-risk countries: the REGICOR (Registre Gironí del cor) and SCORE (Systematic COronary Risk Evaluation) algorithms. METHODS All cardiovascular events during 5-year follow-up in a cohort of patients without coronary disease in nine autonomous Spanish regions were recorded. The levels of different cardiovascular risk factors were measured between 1995 and 1998. Participants were considered high-risk if their 10-year risk was >or=20% with the Framingham algorithm, >or=10%, >or=15% or >or=20% with REGICOR, and >or=5% with SCORE. RESULTS In total, 180 (3.1%) coronary events (112 in men and 68 in women) occurred among the 5732 (57.3% female) participants during follow-up. Of these, 43 died from cerebrovascular disease, and 24 had a non-coronary vascular event. The REGICOR algorithm had the highest positive predictive value for coronary and cardiovascular disease in all age groups. Moreover, with a 10-year risk limit of 10%, it classified less of the population aged 35-74 years as high-risk (i.e., 12.4%) than the Framingham algorithm (i.e., 22.4%). The SCORE and Framingham algorithms classified 8.4% and 16.6% of the population aged 35-64 years, respectively, as having a high cardiovascular disease risk; with REGICOR, the figure was 7.5%. CONCLUSIONS The REGICOR adapted algorithm was the best predictor of cardiovascular events and classified a smaller proportion of the Spanish population aged 35-74 years as high risk than alternative algorithms.