Genetically predicted waist circumference and risk of atrial fibrillation / 中华医学杂志(英文版)

INTRODUCTION@#Observational studies have revealed an association between waist circumference (WC) and atrial fibrillation (AF). However, it is difficult to infer a causal relationship from observational studies because the observed associations could be confounded by unknown risk factors. Therefore, the causal role of WC in AF is unclear. This study was designed to investigate the causal association between WC and AF using a two-sample Mendelian randomization (MR) analysis.@*METHODS@#In our two-sample MR analysis, the genetic variation used as an instrumental variable for MR was acquired from a genome-wide association study (GWAS) of WC (42 single nucleotide polymorphisms with a genetic significance of P <5 × 10 -8 ). The data of WC (from the Genetic Investigation of ANthropometric Traits consortium, containing 232,101 participants) and the data of AF (from the European Bioinformatics Institute database, containing 55,114 AF cases and 482,295 controls) were used to assess the causal role of WC on AF. Three different approaches (inverse variance weighted [IVW], MR-Egger, and weighted median regression) were used to ensure that our results more reliable.@*RESULTS@#All three MR analyses provided evidence of a positive causal association between high WC and AF. High WC was suggested to increase the risk of AF based on the IVW method (odds ratio [OR] = 1.43, 95% confidence interval [CI], 1.30-1.58, P = 2.51 × 10 -13 ). The results of MR-Egger and weighted median regression exhibited similar trends (MR-Egger OR = 1.40 [95% CI, 1.08-1.81], P = 1.61 × 10 -2 ; weighted median OR = 1.39 [95% CI, 1.21-1.61], P = 1.62 × 10 -6 ). MR-Egger intercepts and funnel plots showed no directional pleiotropic effects between high WC and AF.@*CONCLUSIONS@#Our findings suggest that greater WC is associated with an increased risk of AF. Taking measures to reduce WC may help prevent the occurrence of AF.

Polimorfismo rs17817449 del gen FTO y su influencia en variables antropométricas de jóvenes chilenos / rs17817449 polymorphism of the fto gene and its influence on anthropometric variables of young Chileans

Determinar la distribución genotípica y la frecuencia alélica del polimorfismo rs17817449 del gen FTO en jóvenes chilenos y su influencia en variables antropométricas. Los 96 sujetos jóvenes (18-25 años), 43 hombres y 53 mujeres fueron evaluados utilizando genotipificación del polimorfismo rs17817449 del gen FTO en TT, TG y GG mediante polimerase chain reaction (PCR), además de una evaluación Kinenatropométrica para determinar las variables asociadas a composición corporal. Las variables fueron analizadas estadísticamente según su distribución paramétrica y el nivel de significancia estadística fue p<0,05. La distribución genotípica del polimorfismo rs17817449 de FTO en jóvenes chilenos fue: TT: 50 %; TG: 42,7 %; GG 7,3 % y la distribución alélica fue: T: 0,7105 y G: 0,2895. No se encontraron diferencias estadísticamente significativas en las variables antropométricas al analizar los participantes según modelo de dominancia del alelo G. Se determinó la distribución genotípica y la frecuencia alélica del polimorfismo rs17817449 del gen FTO en jóvenes chilenos, datos desconocidos hasta este momento. De acuerdo a nuestros resultados, no existen diferencias antropométricas entre personas con diferentes genotipos del polimorfismo rs17817449 de FTO, agrupadas según modelo de dominancia del alelo G.

The rs17817449 polymorphism of the FTO gene in young Chileans and their influence on anthropometric variables. 96 young subjects (18-25 years old), 43 men and 53 women were evaluated using genotyping of the rs17817449 polymorphism of the FTO gene in TT, TG and GG by means of polymerase chain reaction (PCR), in addition to a Kinenatropometric evaluation to determine the variables associated with body composition. The variables were analyzed statistically according to their parametric distribution and the level of statistical significance was p<0.05. The genotypic distribution of the FTO polymorphism rs17817449 in young Chileans was: TT: 50 %; TG: 42.7 %; GG 7.3 % and the allelic distribution was: T: 0.7105 and G: 0.2895. No statistically significant differences were found in the anthropometric variables when analyzing the participants according to model of dominance of the G allele. The genotypic distribution and the allelic frequency of the rs17817449 polymorphism of the gene were determined FTO in Chilean population, data unknown until now. According to our results, there are no anthropometric differences between people with different genotypes of the FTO polymorphism rs17817449, nor according to the dominance model of the G.

Leptin receptor gene polymorphisms are associated with adiposity and metabolic alterations in Brazilian individuals / Polimorfismos no gene do receptor de leptina são associados com adiposidade e alterações metabólicas em indivíduos brasileiros

OBJECTIVE: The aim of the study was to investigate whether adiposity and metabolic markers, such as leptin, glucose, and lipids, are influenced by leptin (LEP) and leptin receptor (LEPR) gene polymorphisms in a sample of our population. SUBJECTS AND METHODS: A group of 326 individuals of Caucasian-European descent, aged 30 to 80 years, 87 men and 239 women, 148 obese and 178 non-obese, was randomly selected at two clinical hospitals in the city of Sao Paulo, Brazil. All individuals declared their ethnic group as white during the initial interview. Anthropometric measurements, body mass index (BMI), and fat mass were evaluated. Blood samples were drawn for DNA extraction and measurements of leptin, soluble leptin receptor, glucose, and lipids. LEP -2548G>A and LEPR Lys109Arg (c.326A>G), Gln233Arg (c.668A>G) and Lys656Asn (c.1968G>C) polymorphisms were detected by PCR-RFLP. RESULTS: Increased leptin and serum lipids, and LEPR Arg223Arg (GG genotype) were associated with higher risk for obesity (p < 0.05), while reduced risk was found in LEPR Arg109Arg (GG genotype) carriers (OR: 0.38, 95%CI: 0.19-0.77, p = 0.007). Multiple linear regression analysis showed a relationship between LEPR 223Arg, increased waist circumference, and leptinemia (p < 0.05), while LEPR 109Arg was associated with high total cholesterol and triglycerides (p < 0.05). LEPR haplotype 3 (AGG: 109Lys/233Arg/656Lys) carriers have increased risk for obesity (OR: 2.56, 95% CI: 1.19-5.49, p = 0.017). Moreover, this haplotype was associated with increased BMI, waist circumference, and leptinemia (p < 0.05). CONCLUSIONS: LEPR polymorphisms are associated with obesity, hyperleptinemia, and atherogenic lipid profile, suggesting their potential role for leptin resistance and cardiovascular risk. Moreover, LEPR haplotype 3 confers susceptibility to adiposity and hyperleptinemia in our population.

OBJETIVO: O estudo teve por objetivo investigar a influência de polimorfismos nos genes da leptina (LEP) e do receptor de leptina (LEPR) na adiposidade e em marcadores metabólicos, como leptina, glicose e lipí­deos, em uma amostra de nossa população. SUJEITOS E MÉTODOS: Um grupo de 326 indivíduos com idade de 30 a 80 anos, 87 homens e 239 mulheres, 148 obesos e 178 não obesos, e de etnia branca foi selecionado aleatoriamente em dois hospitais clínicos da cidade de São Paulo, Brasil. Medidas antropométricas, índice de massa corporal (IMC) e gordura corporal foram avaliados. Amostras de sangue foram obtidas para extração de DNA e determinações de leptina, receptor de leptina solúvel, glicose e lipídeos. Os polimorfismos LEP -2548G>A e LEPR Lys109Arg (c.326A>G), Gln233Arg (c.668A>G) e Lys656Asn (c.1968G>C) foram detectados por PCR-RFLP. RESULTADOS: Leptina e lipídeos séricos aumentados e LEPR Arg223Arg (genótipo GG) foram associados com maior risco de obesidade (p < 0,05), enquanto foi encontrado risco reduzido de obesidade, em portadores de LEPR Arg109Arg (genótipo GG) (OR: 0,38, 95%CI: 0,19-0,77, p = 0,007). A análise de regressão linear múltipla mostrou relação entre o alelo LEPR 223Arg e circunferência abdominal e leptinemia aumentadas (p < 0,05), enquanto o alelo LEPR 109Arg foi associado com aumento de colesterol total e triglicerídeos (p < 0,05). Os portadores do haplotipo 3 do LEPR (AGG: 109Lys/233Arg/656Lys) tiveram maior risco aumentado para obesidade (OR: 2.56, 95% CI: 1.19-5.49, p = 0,017). Além disso, esse haplótipo foi associado com IMC, circunferência abdominal e leptinemia aumentados (p < 0,05). CONCLUSÕES: Polimorfismos de LEPR são associados com obesidade, hiperleptinemia e perfil lipídico aterogênico sugerindo seu papel potencial para a resistência à leptina e risco cardiovascular.

Índice cintura-cadera contra perímetro cintura para el diagnóstico del síndrome metabólico en niños y adolescentes con familiares de primer grado diabéticos tipo 1 / Waist-hip index versus waist circumference for diagnosis of metabolic syndrome in first degree-children and adolescents relatives of persons with type 1 diabetes

Objetivo: comparar las mediciones de perímetro cintura e índice cintura-cadera para determinar la frecuencia del síndrome metabólico en familiares de primer grado de personas con diabetes tipo 1, utilizando diferentes definiciones pediátricas. Métodos: se estudiaron 224 familiares de primer grado de personas con diabetes tipo 1, en edades comprendidas entre los 4 y los 19 años. Se les determinó peso, talla, perímetro cintura y perímetro cadera, tensión arterial, glucemia, triglicéridos y HDL-colesterol. Se aplicaron las definiciones de síndrome metabólico según los criterios de Cook, Ford, la Federación Internacional de Diabetes y del consenso cubano. Se realizó una variante del consenso cubano utilizando: índice de masa corporal e índice cintura-cadera, según tablas cubanas, valores de glucosa ³ 5,6 mmol/L y tensión arterial ³ 90 percentil (tablas cubanas). Se tomaron, de forma independiente, los criterios de HDL-colesterol y triglicéridos. Empleamos el índice cintura-cadera de las tablas cubanas, el perímetro cintura sugerido por la Asociación Latinoamericana de Diabetes y el europeo para las definiciones estudiadas. Para la comparación de las frecuencias del síndrome metabólico, se usó la prueba exacta de Fisher. Resultados: la frecuencia del síndrome metabólico al aplicar la variante del consenso cubano fue de 9,37 por ciento (21/224). Al comparar la variante del consenso cubano con las definiciones de Cook, Ford y la Federación Internacional de Diabetes (que utiliza el perímetro cintura de la Asociación Latinoamericana de Diabetes), se observó diferencia significativa con Cook y la Federación Internacional de Diabetes (4,01 por ciento, p= 0,0360; 1,33 por ciento, p= 0,0002 respectivamente). Al confrontar la presencia del síndrome metabólico de la variante del consenso cubano con Cook (8,48 por ciento; 19/224) y Ford (8,93 por ciento; 20/224), teniendo en cuenta el índice cintura-cadera de las tablas cubanas, podemos detectar frecuencias similares de familiares de primer grado de personas con diabetes tipo 1 con síndrome metabólico. En cambio, encontramos diferencias significativas cuando comparamos las frecuencias del síndrome metabólico de la variante del consenso cubano (p= 0,0019), de Cook (p= 0,0053) y de Ford (p= 0,0032), con la definición sugerida por la Federación Internacional de Diabetes (2,23 pr ciento; 5/224) empleando el índice cintura-cadera. Conclusiones: nuestros datos indican que para el diagnóstico del síndrome metabólico debemos utilizar el índice cintura-cadera y no el perímetro cintura sugerido por la Asociación Latinoamericana de Diabetes, aún sin presentar datos propios del perímetro cintura de la población cubana(AU)

Objective: to compare the measurements of waist circumference and waist-hip circumference to determine the frequency of metabolic syndrome in first degree relatives of persons with type 1diabetes, using different pediatric definitions. Methods: two hundred twenty four first degree relatives of persons with type 1 diabetes were studied in ages from 4 to 10 years. Weight, height, waist-hip circumference, blood pressure, glycemia, triglycerides and HDL-cholesterol were determined. The definitions of metabolic syndrome according to Cook, Ford, International Federation of Diabetes and the Cuban consensus were applied. A variant of Cuban consensus was performed using: body mass index and waist-hip index according the Cuban tables, values of glucose ³ 5,6 mmol/L and blood pressure ³ 90 percentile (Cuban tables). In an independent way, criteria of HDL-cholesterol and triglycerides were taken into account. The waist-hip index of Cuban tables, the waist circumference suggested by the Latin-American and European Association of Diabetes for study definitions were applied. For comparison of frequencies of metabolic syndrome the Fisher exact test was used. Results: the frequency of metabolic syndrome with application of Cuban consensus variant was of 9,37 percent (21/224). Comparing the above variant with the definitions of Cook, Ford and of the International Federation of Diabetes (using the waist circumference of the Latin-American Association of Diabetes, there was a significant difference between Cook and the International Federation of Diabetes (4,01 percent, p= 0,0360; 1,33 percent, p= 0,0002, respectively). Comparing the presence of metabolic syndrome of the Cuban consensus variant with Cook (8,48 percent; 19/224) and Ford (8,93 percent; 20/224) taking into account the waist-hip index of the Cuban tables, it is possible to detect similar frequencies of first degree relatives of persons with type 1 diabetes with metabolic syndrome. On the other hand, we found significant differences comparing the frequencies of metabolic syndrome of the Cuban consensus variant (p= 0,0019), of Cook (p= 0,0053) and of Ford (p= 0,0032) with the definition suggested by the International Federation of Diabetes (2,23 percent; 5/224) using the waist-hip index. Conclusions: our data demonstrate that for the diagnosis of metabolic syndrome we must to use the waist-hip index and not the circumference suggested by the Latin-American Association of Diabetes, still without to present own data of waist-hip circumference of the Cuban population(AU)

Avaliação antropométrica e metabólica de parentes de primeiro grau do sexo masculino de mulheres com síndrome do ovário policístico / Anthropometric and metabolic evaluation of first-degree male relatives of women with polycystic ovary syndrome

OBJETIVO: avaliar as características clínicas e laboratoriais de parentes de primeiro grau do sexo masculino de pacientes com diagnóstico confirmado de síndrome de ovários policísticos (SOP) e comparar os achados com um grupo controle sem história familiar de SOP. MÉTODOS: foram selecionados aleatoriamente 28 homens com idade entre 18 e 65 anos que possuíam parentesco de primeiro grau com mulheres diagnosticadas com SOP e 28 controles pareados por idade, cintura e índice de massa corporal (IMC). RESULTADOS: homens com parentesco de 1º grau com mulheres com SOP comparados ao Grupo Controle apresentaram níveis mais elevados de triglicerídeos (189,6±103,1 versus 99,4±37,1; p<0,0001), HOMA-IR (Homeostase Model Assesment) (3,5±9,1 versus 1,0±1,0; p=0,0077) e glicemia (130,1±81,7 versus 89,5±7,8; p=0,005), além de menores níveis da globulina ligadora de hormônios sexuais (SHBG) (23,8±13,8 versus 31,1±9,1; p=0,003). Os níveis de SHBG se correlacionaram independentemente com os níveis de triglicérides. Os parentes de 1º grau também apresentavam mais sinais clínicos de hiperandrogenismo. CONCLUSÕES: parentes de primeiro grau do sexo masculino das pacientes com SOP apresentam maior grau de dislipidemia e de resistência à insulina, além de níveis mais baixos de SHBG com mais sinais clínicos de hiperandrogenismo. Esses achados sugerem que a resistência à insulina pode ter origem hereditária em indivíduos com história familiar de SOP, independentemente de parâmetros antropométricos.

PURPOSE: to evaluate clinical and laboratory characteristics of first-degree male relatives of patients with a confirmed diagnosis of polycystic ovary syndrome (PCOS) and to compare the findings with a control group with no family history of PCOS. METHODS: we randomly selected 28 male individuals aged 18 to 65 years who were first-degree relatives of women diagnosed with PCOS and 28 controls matched for age, waist and body mass index (BMI). RESULTS: men with 1st degree kinship with women with PCOS had higher levels of triglycerides (189.6±103.1 versus 99.4±37.1, p<0.0001), Homeostasis Model Assessment (HOMA-IR) (3.5±9.1 versus 1.0±1.0, p=0.0077) and glucose (130.1±81.7 versus 89.5±7.8, p=0.005), and lower levels of sex hormone binding globulin (SHBG) (23.8±13.8 versus 31.1±9.1, p=0.003). SHBG levels correlated independently with triglyceride levels. These individuals also had more clinical signs of hyperandrogenism. CONCLUSIONS: male individuals who are first-degree relatives of patients with PCOS have a higher degree of dyslipidemia and insulin resistance, lower levels of SHBG, and more evident clinical signs of hyperandrogenism. These findings suggest that insulin resistance may be of hereditary origin in individuals with a family history of PCOS regardless of anthropometric parameters.