PERFORMACE OF TRIGLYCERIDE-GLUCOSE INDEX ON DIAGNOSIS AND STAGING OF NAFLD IN OBESE PATIENTS.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is the most prevalent liver disease in the world, and its prevalence is increasing alongside obesity. In United States, NAFLD is already the second leading cause of liver transplantation. The spectrum of the disease ranges from simple steatosis, which has a benign course, to steatohepatitis, which may progress to cirrhosis and its complications. The rising of noninvasive methods for diagnosing and staging non-alcoholic steatohepatitis (NASH) and fibrosis decreases the need of liver biopsy, as well as the costs and the occurrence of complications related to it. OBJECTIVE: To analyze the performance of the triglyceride-glucose index to evaluate steatosis, NASH and liver fibrosis in obese patients with NAFLD. METHODS: This is a retrospective cross-sectional study. Every medical record of patients who were candidates for bariatric surgery at a leading hospital in Southern Brazil were analyzed. The triglyceride-glucose index (TyG Index), a method composed only of two simple laboratory tests (serum triglycerides and fasting glucose levels), was performed prior to surgery. The TyG Index performance regarding the anatomopathological findings was evaluated, and the AUROC curve was calculated to evaluate the best cut-off point for diagnosing steatosis, non-alcoholic steatohepatitis and liver fibrosis grade. Also, the NAFLD fibrosis Score (NFS) was evaluated. RESULTS: A total of 423 patients were evaluated. The TyG Index with a cut-off point of 8.76 excluded significant simple steatosis (grade 2-3) in obese patients, with 67.6% sensitivity, 65.1% specificity, 46.3% positive predictive value (PPV), 81.8% negative predictive value (NPV), 65.8% accuracy and 0.66 AUROC (P=0.005). In the evaluation of NASH, the TyG Index with a cut-off point of 8.82 excluded significant NASH (grade 2-3) with 57.3% sensitivity, 58.6% specificity, 33.7% PPV, 78.8% NPV, 58.2% accuracy and 0.58 AUROC (P=0.022). When evaluating liver fibrosis, the TyG Index with a cut-off point of 8.91 showed a sensitivity of 61.8%, a specificity of 62.5%, a PPV of 13.8 and a NPV of 94.4% for exclusion of advanced fibrosis (F3-4), with a 62.4% accuracy and 0.69 AUROC (P<0.001). When analyzing the performance of NFS in the diagnosis of advanced fibrosis, the cut-off point <-1.455 excluded advanced fibrosis with sensitivity of 59.4%, specificity of 51%, PPV of 11%, NPV of 92.4% and accuracy of 51.7%. However, the cut-off point of 0.676 to diagnose advanced fibrosis presented sensitivity of 21.9%, specificity of 83%, PPV of 11.7%, NPV of 91.2% and 77.3% accuracy. The AUROC was 0.54 (P=0.480). CONCLUSION: TyG Index did not perform well in the diagnosis of significant steatosis and NASH. However, it was able to exclude advanced fibrosis in obese patients who are candidates for bariatric surgery.

Avaliação do desempenho do índice triglicerídeo-glicose no diagnóstico e estadiamento da DHGNA em pacientes obesos / Performace of triglyceride-glucose index on diagnosis and staging of nafld in obese patients

ABSTRACT BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is the most prevalent liver disease in the world, and its prevalence is increasing alongside obesity. In United States, NAFLD is already the second leading cause of liver transplantation. The spectrum of the disease ranges from simple steatosis, which has a benign course, to steatohepatitis, which may progress to cirrhosis and its complications. The rising of noninvasive methods for diagnosing and staging non-alcoholic steatohepatitis (NASH) and fibrosis decreases the need of liver biopsy, as well as the costs and the occurrence of complications related to it. OBJECTIVE: To analyze the performance of the triglyceride-glucose index to evaluate steatosis, NASH and liver fibrosis in obese patients with NAFLD. METHODS: This is a retrospective cross-sectional study. Every medical record of patients who were candidates for bariatric surgery at a leading hospital in Southern Brazil were analyzed. The triglyceride-glucose index (TyG Index), a method composed only of two simple laboratory tests (serum triglycerides and fasting glucose levels), was performed prior to surgery. The TyG Index performance regarding the anatomopathological findings was evaluated, and the AUROC curve was calculated to evaluate the best cut-off point for diagnosing steatosis, non-alcoholic steatohepatitis and liver fibrosis grade. Also, the NAFLD fibrosis Score (NFS) was evaluated. RESULTS: A total of 423 patients were evaluated. The TyG Index with a cut-off point of 8.76 excluded significant simple steatosis (grade 2-3) in obese patients, with 67.6% sensitivity, 65.1% specificity, 46.3% positive predictive value (PPV), 81.8% negative predictive value (NPV), 65.8% accuracy and 0.66 AUROC (P=0.005). In the evaluation of NASH, the TyG Index with a cut-off point of 8.82 excluded significant NASH (grade 2-3) with 57.3% sensitivity, 58.6% specificity, 33.7% PPV, 78.8% NPV, 58.2% accuracy and 0.58 AUROC (P=0.022). When evaluating liver fibrosis, the TyG Index with a cut-off point of 8.91 showed a sensitivity of 61.8%, a specificity of 62.5%, a PPV of 13.8 and a NPV of 94.4% for exclusion of advanced fibrosis (F3-4), with a 62.4% accuracy and 0.69 AUROC (P<0.001). When analyzing the performance of NFS in the diagnosis of advanced fibrosis, the cut-off point <-1.455 excluded advanced fibrosis with sensitivity of 59.4%, specificity of 51%, PPV of 11%, NPV of 92.4% and accuracy of 51.7%. However, the cut-off point of 0.676 to diagnose advanced fibrosis presented sensitivity of 21.9%, specificity of 83%, PPV of 11.7%, NPV of 91.2% and 77.3% accuracy. The AUROC was 0.54 (P=0.480). CONCLUSION: TyG Index did not perform well in the diagnosis of significant steatosis and NASH. However, it was able to exclude advanced fibrosis in obese patients who are candidates for bariatric surgery.

RESUMO CONTEXTO: A doença hepática gordurosa não-alcoólica (DHGNA) é a doença hepática mais prevalente no mundo. Nos Estados Unidos, a DHGNA já é a segunda causa de transplante hepático. O espectro da doença abrange desde a esteatose simples, que apresenta curso benigno, até esteato-hepatite não-alcoólica (EHNA), que pode progredir para cirrose e suas complicações. O desenvolvimento de métodos não invasivos para o diagnóstico e estadiamento da EHNA e da fibrose hepática visa diminuir a necessidade de biópsia hepática, um procedimento invasivo e não raro associado a complicações. OBJETIVO: Analisar o desempenho do índice triglicerídeo-glicose (TyG Index) para o diagnóstico e estadiamento da DHGNA em pacientes obesos. MÉTODOS: Este é um estudo transversal retrospectivo. Foram analisados todos os prontuários de pacientes candidatos a cirurgia bariátrica em um hospital de referência do Sul do Brasil e calculado o TyG Index, um escore composto por dois exames laboratoriais (triglicerídeos e glicose de jejum), realizados previamente à cirurgia. O desempenho do TyG Index em relação aos achados anatomopatológicos hepáticos foi avaliado, e calculada a curva ROC para avaliação de esteatose simples, EHNA e fibrose hepática. O NAFLD Fibrosis Score (NFS) também foi avaliado. RESULTADOS: Foram avaliados 423 pacientes. O melhor ponto de corte do TyG Index para a exclusão de esteatose simples significativa (grau 2-3) foi de 8,76, com sensibilidade 67,6%, especificidade 65,1%, valor preditivo positivo (VPP) 46,3%, valor preditivo negativo (VPN) 81,8%, acurácia 65,8% e AUROC 0,66 (P=0,005). Na avaliação de EHNA significativa (grau 2-3), o melhor ponto de corte foi de 8,82 com sensibilidade 57,3%, especificidade 58,6%, VPP 33,7%, VPN 78,8%, acurácia 58,8% e AUROC 0,58 (P=0,022). Em relação à fibrose avançada (grau 3-4), o melhor ponto de corte do TyG Index foi de 8,91 com sensibilidade 61,8%, especificidade 62,5%, VPP 13,8%, VPN 94,4%, acurácia 62,4% e AUROC 0,69 (P<0,001). Ao analisarmos o desempenho do NFS no diagnóstico de fibrose avançada, o ponto de corte de <-1,455 excluiu fibrose avançada com sensibilidade 59,4%, especificidade 51%, VPP 11%, VPN 92,4% e acurácia 51,7%. Entretanto, o ponto de corte de 0,676 para fibrose avançada apresentou sensibilidade de 21,9%, especificidade 83%, VPP 11,7%, VPN 91,2% e acurácia 77,3%. A AUROC foi de 0,54 (P=0,480). CONCLUSÃO: O TyG Index não apresentou bom desempenho para o diagnóstico e estadiamento da esteatose simples e da EHNA. Entretanto, foi capaz de excluir fibrose avançada em pacientes obesos candidatos a cirurgia bariátrica.

Role of micronutrients in staging of nonalcoholic fatty liver disease: A retrospective cross-sectional study.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) presents high incidence throughout the world and has been progressively increasing in prevalence. This disease has a heterogeneous natural history, including simple steatosis, nonalcoholic steatohepatitis (NASH), and cirrhosis. The factors that determine its evolution to more severe forms of the disease are still poorly understood, and micronutrients with antioxidant potential may be involved in the pathophysiology of the disease. AIM: To evaluate the relationship between serum levels of micronutrients and the severity of NAFLD. METHODS: A retrospective, observational and cross-sectional study was conducted. This study included all patients undergoing bariatric surgery who experienced liver biopsy during the procedure, and had serum levels of micronutrients (vitamin D, vitamin B12, zinc, iron, and magnesium), which was assessed in a preoperative evaluation conducted at a reference center in southern Brazil. RESULTS: A total of 614 patients were analyzed, of which 93% had steatosis, 70.7% had NASH, and 49.3% had some degree of fibrosis. Serum levels of vitamin D were negatively correlated with the severity of steatosis and NASH, and serum levels of vitamin B12 were positively correlated with the severity of steatosis and fibrosis. The other micronutrients showed no association with NAFLD staging. CONCLUSION: Serum levels of vitamin D are inversely related to the severity of steatosis and NASH, and serum levels of vitamin B12 are higher in more advanced stages of simple steatosis and liver fibrosis. Serum levels of zinc, iron, and magnesium were not associated with NAFLD severity.

Effect of Bariatric Surgery on High-Density Lipoprotein (HDL) Cholesterol in Non-diabetic Patients with Severe Obesity.

BACKGROUND: This study evaluated changes in serum high-density lipoprotein cholesterol (HDL-C) induced by laparoscopic bariatric surgery (BS) in non-diabetic obese subjects with low (L-HDL-C) or normal (N-HDL-C) levels of HDL-C. We assessed whether increased HDL-C is associated with weight loss, serum non-HDL cholesterol (non-HDL-C), serum triglycerides (TG), and physical activity (PA) before and 6 and 15 months after BS. METHODS: In this prospective cohort study, 71 subjects undergoing BS (42 by Roux-en-Y gastric bypass and 29 by sleeve gastrectomy) were evaluated for the % Excess Weight Loss (%EWL), waist circumference (WC), serum levels of glucose, glycosylated hemoglobin, TG, HDL-C, non-HDL-C, and LDL-C, and the degree, time, and energy expenditure related to PA. The short version of the International Physical Activity Questionnaire was used to assess PA. RESULTS: Levels of HDL-C significantly increased 15 months after BS (p < 0.001) in subjects with low (p < 0.001) or normal (p = 0.017) values at baseline. A similar %EWL, decrease in WC, glucose, non-HDL-C, and LDL-C levels and increase in energy expenditure related to PA, was observed in both groups (L-HDL-C and N-HDL-C) at 15 months after BS. However, the L-HDL-C group presented greater decrease in TG levels compared with N-HDL-C group (p = 0.004). In subjects with increased HDL-C 15 months after BS, there was an association between this increase and the %EWL (p = 0.030), but there was no association with the change in PA. CONCLUSIONS: Irrespective of PA after BS, subjects with low and normal HDL-C levels at baseline showed an increase in HDL-C after BS, and this increase was associated with %EWL induced by BS.

Metabolic syndrome resolution by Roux-en-Y gastric bypass in a real world: a case control study.

OBJECTIVES: the aim of this study was to evaluate the efficacy of Roux-en-Y Gastric Bypass (RYGB), compared with nonsurgical treatment (NS group), as an instrument for inducing remission of co-morbidities related to Metabolic Syndrome (MetS) in patients with Obesity, grades 2 and 3 (Ob2,3). METHODS: two hundred and fifty eight Ob2,3 patients were selected in a retrospective analysis and included in a case control study. MetS was defined as described by the International Diabetes Federation. One hundred and twenty-nine of these patients underwent RYGB (S group), and 129 were assessed as an NS group. RESULTS: at baseline, S and NS groups did not differ in BMI, age, female sex and prevalence of MetS (p>0.05). For the S group the outcomes were a reduction in BMI of 38.1% (p<0.001), waist circumference of 28.6% (p<0.001), fasting plasma glucose of 10.5% (p<0.001), serum LDL-cholesterol of 21.9% (p<0.001) and of 85% in the number of patients with MetS (p<0.001). For the NS group, only a decrease of 4.12%(p=0.047) in triglyceride levels and of 5.9%(p=0.031) in Diastolic Blood Pressure was observed. In the NS group, 98.6% of the patients continued to have MetS. The number needed to treat (NNT) with surgery to resolve one case of MetS was 1.2 (CI 95%: 1.1 - 1.4). CONCLUSION: in the real world, in the South of Brazil, compared with NS treatment and after 1 year of observation, RYGB is highly effective for decreasing the prevalence of MetS.

Abordagem videolaparoscópica para divertículo esofágico / Laparoscopic approach for esophageal diverticula

A toracotomia persiste como a abordagem clássica para cirurgia dos divertículos de esôfago. Seguindo a evolução das técnicas cirúrgicas minimamente invasivas, apresenta-se neste relato um procedimento alternativo, onde a abordagem laparoscópica transhiatal foi a opção terapêutica para um divertículo esofágico epifrênico. Devido aos resultados apresentados, sugere-se que a videolaparoscopia deva ser considerada como importante opção em centros com experiência em cirurgia videolaparoscópica avançada.

Thoracotomy remains as the classic approach to surgery for esophageal diverticula. Following the evolution of minimally invasive surgical techniques, this report presents an alternative procedure, where the approach of transhiatal laparoscopy was the therapeutic option for an epiphrenic esophageal diverticulum. Due to the results presented, it is suggested that laparoscopy should be considered as an important option in centers with experience in advanced laparoscopic surgery.

Estudo dos linfonodos da curvatura gástrica menor no câncer do esôfago / Study of the gastric lesser curvature lymph nodes in esophageal cancer

Os autores estudam os linfonodos da curvatura gástrica menor em trinta pacientes com carcinoma epidermóide do esôfago. Correlacionam o grau de acometimento tumoral desses linfonodos com a localizaçäo, tamanho, grau de diferenciaçäo histológica do tumor e a penetraçäo na parede do órgäo. A análise dos dados aponta significante acometimento metastático da curvatura gástrica menor; 24 dos 179 gânglios examinados. Näo houve diferença significante entre a localizaçäo, tamanho e grau de diferenciaçäo do tumor; porém, näo houve linfonodos positivos nos pacientes em que a lesäo foi restrita às camadas musculares näo invadindo a adventícia. A conclusäo aponta para a ressecçäo da curvatura gástrica menor, independente do tamanho, localizaçäo e grau de diferenciaçäo do tumor, mesmo no tratamento paliativo, pois existe a possibilidade de transporem a regiäo cervical linfonodos comprometidos, os quais, eventualmente, poderäo comprimir o neoesôfago, além de ficarem fora do campo de radioterapia pós-operatória