RESUMO
Objetivos: Evaluar criticamente las implicaciones clinicas de la utilizacion del perfil lipidico sin ayuno en lugar de perfiles de lipidos con ayuno y proporcionar orientacion para la elaboracion de informes de laboratorio sobre perfiles lipidicos anormales con ayuno y sin ayuno. Metodos y Resultados: Abundantes datos observacionales, en los que perfiles lipidicos medidos aleatoriamente sin ayuno se han comparado con perfiles lipidicos determinados en condiciones de ayuno, indican que las variaciones medias maximas de 1-6 h despues de ingestas habituales no son clinicamente significativas [+0,3 mmol/L (+26 mg/dL) para trigliceridos; -0,2 mmol/L (-8 mg/dL) para colesterol total; -0,2 mmol/L (-8 mg/dL) para colesterol-LDL; +0,2 mmol/L (+8 mg/dL) para colesterol de remanentes calculado; -0,2 mmol/L (-8 mg/dL) para el colesterol no-HDL calculado]; las concentraciones de colesterol-HDL, apolipoproteina A1, apolipoproteina B, y lipoproteina(a) no se ven afectados por el estado de ayuno/ no ayuno. Ademas, las concentraciones en ayunas y sin ayuno varian de manera similar con el tiempo y son comparables en la prediccion de la enfermedad cardiovascular. Para mejorar el cumplimiento del paciente con las condiciones para la determinacion del perfil lipidico, por lo tanto, se recomienda el uso rutinario de los perfiles lipidicos sin ayuno, mientras que se puede considerar la toma de muestra en ayunas cuando los trigliceridos sin ayuno son >5 mmol/L (440 mg/dL). Para las muestras sin ayuno, los informes de laboratorio deberian marcar como concentraciones anormales a trigliceridos ≥2 mmol/L (175 mg/dL), colesterol total ≥5 mmol/L (190 mg/dL), colesterol-LDL ≥3 mmol/L (115 mg/dL), colesterol remanente calculado ≥0,9 mmol/L (35 mg/dL), colesterol no-HDL calculado ≥3.9 mmol/L (150 mg/dL), HDL colesterol ≤1 mmol/L (40 mg/dL), apolipoproteina A1 ≤1,25 g/L (125 mg/dL), apolipoproteina B ≥1,0 g/L (100 mg/dL), y lipoproteina(a) ≥50 mg/dL (percentil 80); para muestras con ayuno, las concentraciones anormales corresponden a trigliceridos ≥1,7 mmol/L (150 mg/dL). Aquellas concentraciones que ponen en peligro la vida requieren derivacion inmediata debido al riesgo de pancreatitis cuando los trigliceridos son >10 mmol/L (880 mg/dL), de hipercolesterolemia familiar homocigotica cuando el colesterol-LDL es >13 mmol/L (500 mg/dL) o hipercolesterolemia familiar heterocigota cuando el colesterol-LDL es >5 mmol/L (190 mg/dL), y debido al riesgo cardiovascular muy alto cuando la lipoproteina(a) es >150 mg/dL (percentil 99). Conclusiones: Recomendamos la utilizacion de rutina de muestras de sangre sin ayuno para la evaluacion del perfil lipidico plasmatico. Los informes de laboratorio deberian marcar resultados anormales basandose en valores de corte deseables. Las determinaciones con ayuno y sin ayuno deben ser complementarias, pero no se excluyen mutuamente.
Aims: To critically evaluate the clinical implications of the use of non-fasting rather than fasting lipid profiles and to provide guidance for the laboratory reporting of abnormal non-fasting or fasting lipid profiles. Methods and Results: Extensive observational data, in which random non-fasting lipid profiles have been compared with those determined under fasting conditions, indicate that the maximal mean changes at 1-6 h after habitual meals are not clinically significant [+0.3 mmol/L (26 mg/dL) for triglycerides; -0.2 mmol/L (8 mg/dL) for total cholesterol; -0.2 mmol/L (8 mg/dL) for LDL cholesterol; +0.2 mmol/L (8 mg/dL) for calculated remnant cholesterol; -0.2 mmol/L (8 mg/dL) for calculated non-HDL cholesterol]; concentrations of HDL cholesterol, apolipoprotein A1, apolipoprotein B, and lipoprotein(a) are not affected by fasting/nonfasting status. In addition, non-fasting and fasting concentrations vary similarly over time and are comparable in the prediction of cardiovascular disease. To improve patient compliance with lipid testing, we therefore recommend the routine use of non-fasting lipid profiles, whereas fasting sampling may be considered when non-fasting triglycerides are >5 mmol/L (440 mg/dL). For nonfasting samples, laboratory reports should flag abnormal concentrations as triglycerides ≥2 mmol/L (175 mg/dL), total cholesterol ≥5 mmol/L (190 mg/dL), LDL cholesterol ≥3 mmol/L (115 mg/dL), calculated remnant cholesterol ≥0.9 mmol/L (35 mg/dL), calculated non-HDL cholesterol ≥3.9 mmol/L (150 mg/dL), HDL cholesterol ≤1 mmol/L (40 mg/dL), apolipoprotein A1 ≤1.25 g/L (125 mg/dL), apolipoprotein B ≥1.0 g/L (100 mg/dL), and lipoprotein(a) ≥50 mg/dL (80th percentile); for fasting samples, abnormal concentrations correspond to triglycerides ≥1.7 mmol/L (150 mg/dL). Life-threatening concentrations require separate referral for the risk of pancreatitis when triglycerides are >10 mmol/L (880 mg/dL), for homozygous familial hypercholesterolemia when LDL cholesterol is >13 mmol/L (500 mg/dL), for heterozygous familial hypercholesterolemia when LDL cholesterol is >5 mmol/L (190 mg/dL), and for very high cardiovascular risk when lipoprotein(a) >150 mg/dL (99th percentile). Conclusions: We recommend that non-fasting blood samples be routinely used for the assessment of plasma lipid profiles. Laboratory reports should flag abnormal values on the basis of desirable concentration cutpoints. Non-fasting and fasting measurements should be complementary but not mutually exclusive.
Assuntos
Metabolismo dos Lipídeos , Estudos Observacionais como Assunto , TraduçõesRESUMO
This study assessed plasma lipids and other cardiovascular risk factors in adolescents in a developing Latin American country and compared those risk factors to those of adolescents in the United States of America, where the risk of heart disease is high. In a cross-sectional study, data were collected from September 1998 to April 1999 on 161 Costa Rican adolescents between the ages of 12 and 20. A general questionnaire was used to collect demographic, smoking, socioeconomic, and women's health data. Anthropometric measurements, blood pressure, and a fasting blood sample were taken. The Costa Rican males had lower levels of total cholesterol than did the Costa Rican females (mean +_ standard error of the mean (SEM), 149 +_ 6.5 mg/dL vs. 158 +_ 6.3 mg/dL). This was mainly due to lower high-density lipoprotein (HDL) cholesterol in males than in females (mean +_ SEM, 38 +_ 2.0 mg/dL vs. 44 +_ 2.4 mg/dL. As compared to the United States, adolescents in this study had lower levels of total cholesterol, largely due to lower HDL cholesterol. Both genders of Costa Ricans had levels of low-density lipoprotein (LDL) cholesterol that were similar to those of counterpart groups in the United States. Costa Rican male and female adolescents had higher LDL/HDL ratios than did their United States counterparts. Therefore, as compared to the United States, Costa Rican adolescents have an adverse lipid profile as demonstrated by a higher LDL/HDL ratio. overweight prevalence in Costa Rica was 13 por cent, approaching the 15 por cent overall level of the United States
Assuntos
Lipídeos , Plasma , Fatores de Risco , Adolescente , Cardiopatias , Estudos Transversais , Costa Rica , Estados UnidosRESUMO
This study assessed plasma lipids and other cardiovascular risk factors in adolescents in a developing Latin American country and compared those risk factors to those of adolescents in the United States of America, where the risk of heart disease is high. In a cross-sectional study, data were collected from September 1998 to April 1999 on 161 Costa Rican adolescents between the ages of 12 and 20. A general questionnaire was used to collect demographic, smoking, socioeconomic, and women's health data. Anthropometric measurements, blood pressure, and a fasting blood sample were taken. The Costa Rican males had lower levels of total cholesterol than did the Costa Rican females (mean +_ standard error of the mean (SEM), 149 +_ 6.5 mg/dL vs. 158 +_ 6.3 mg/dL). This was mainly due to lower high-density lipoprotein (HDL) cholesterol in males than in females (mean +_ SEM, 38 +_ 2.0 mg/dL vs. 44 +_ 2.4 mg/dL. As compared to the United States, adolescents in this study had lower levels of total cholesterol, largely due to lower HDL cholesterol. Both genders of Costa Ricans had levels of low-density lipoprotein (LDL) cholesterol that were similar to those of counterpart groups in the United States. Costa Rican male and female adolescents had higher LDL/HDL ratios than did their United States counterparts. Therefore, as compared to the United States, Costa Rican adolescents have an adverse lipid profile as demonstrated by a higher LDL/HDL ratio. overweight prevalence in Costa Rica was 13 por cent, approaching the 15 por cent overall level of the United States
En este estudio se investigaron los lípidos plasmáticos y otros factores de riesgo cardiovascular en adolescentes de un país latinoamericano en desarrollo y se compararon con los factores de riesgo de los adolescentes de los Estados Unidos de América (EUA), en los que el riesgo de cardiopatía es alto. El estudio, de tipo transversal, se realizó entre septiembre de 1998 y abril de 1999, y recogió datos de 161 adolescentes costarricences de 12 a 20 años de edad. Mediante un cuestionario general se registró la información demográfica, socioeconómica, obstétrico-ginecológica y sobre el consumo de tabaco. Se efectuaron mediciones antropométricas, se registró la tensión arterial y se obtuvieron muestras de sangre en ayunas. Los varones costarricenses tenían concentraciones totales de colesterol inferiores a las de las mujeres costarricenses (media ± error estándar de la media (EEM) 149 ± 6,5 mg/dL frente a 158 ± 6,3 mg/dL). Esto se debió, sobre todo, a las menores concentraciones de colesterol de las lipoproteínas de alta densidad (HDL) en los hombres que en las mujeres (media ± EEM, 38 ± 2,0 mg/dL frente a 44 ± 2,4 mg/dL). En comparación con los adolescentes de los EUA, los de Costa Rica tenían menores niveles de colesterol total, debido sobre todo al colesterol de las HDL. Los costarricenses de ambos sexos tenían concentraciones de colesterol de las lipoproteínas de baja densidad (LDL) similares a las de los grupos correspondientes en los EUA y mayores razones LDL/HDL. Por tanto, en comparación con los adolescentes de los EUA, los costarricenses tenían un perfil lipídico adverso, como demuestra la mayor razón LDL/HDL. La prevalencia del sobrepeso en Costa Rica fue del 13%, cercana al 15% global de los EUA.