RESUMEN
BACKGROUND AND AIMS: Nonalcoholic fatty liver disease is epidemiologically associated with hepatic and metabolic disorders. The aim of this study was to examine whether hepatic fat accumulation has a causal role in determining liver damage and insulin resistance. METHODS: We performed a Mendelian randomization analysis using risk alleles in PNPLA3, TM6SF2, GCKR and MBOAT7, and a polygenic risk score for hepatic fat, as instruments. We evaluated complementary cohorts of at-risk individuals and individuals from the general population: 1515 from the liver biopsy cohort (LBC), 3329 from the Swedish Obese Subjects Study (SOS) and 4570 from the population-based Dallas Heart Study (DHS). RESULTS: Hepatic fat was epidemiologically associated with liver damage, insulin resistance, dyslipidemia and hypertension. The impact of genetic variants on liver damage was proportional to their effect on hepatic fat accumulation. Genetically determined hepatic fat was associated with aminotransferases, and with inflammation, ballooning and fibrosis in the LBC. Furthermore, in the LBC, the causal association between hepatic fat and fibrosis was independent of disease activity, suggesting that a causal effect of long-term liver fat accumulation on liver disease is independent of inflammation. Genetically determined hepatic steatosis was associated with insulin resistance in the LBC and SOS. However, this association was dependent on liver damage severity. Genetically determined hepatic steatosis was associated with liver fibrosis/cirrhosis and with a small increase in risk of type 2 diabetes in publicly available databases. CONCLUSION: These data suggest that long-term hepatic fat accumulation plays a causal role in the development of chronic liver disease.
Asunto(s)
Tejido Adiposo/fisiología , Resistencia a la Insulina/fisiología , Cirrosis Hepática/etiología , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Aciltransferasas/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Adulto , Enfermedad Crónica , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Marcadores Genéticos/genética , Humanos , Lipasa/genética , Masculino , Proteínas de la Membrana/genética , Análisis de la Aleatorización Mendeliana , Estudios ProspectivosRESUMEN
PURPOSE: Hypoparathyroidism is one of the most common and most feared complications of total thyroidectomy (TT). The aim of this study is to detect possible markers that may facilitate early tracing of hypocalcaemia-prone patients in order to reduce clinical cost by optimizing patient discharge and to avoid unnecessary treatment. METHODS: Over an 18-month period, 995 patients, 23 % male and 77 % female, aged 52.9 ± 13.4 years, underwent TT in ten Lombardy hospitals. The following parameters were analyzed: calcaemia before and 12-24 and 48 h after surgery, pre- and post-operative parathyroid hormone (PTH) at 24 h and pre-operative 25OH vitamin D. RESULTS: Mortality was nil and morbidity was 22.4 %. Mean 24-h calcaemia and PTH were 2.17 ± 0.15 mmol/l and 31.81 ± 20.35 pg/ml, respectively; mean 24-h PTH decay was 36.7 ± 34.12 %. Four hundred seventy-three (47.5 %) patients were hypocalcaemic at discharge; 142 of whom had transient hypoparathyroidism that became permanent in 27. Patients developing hypocalcaemia had significantly higher values of PTH and calcium decay. At multiple logistic regression, only 24-h calcium decay, PTH drop and the presence of symptoms and parathyroid auto-grafting were significantly related to hypoparathyroidism. The association of these factors had a 99.2 % negative predictive value (NPV) for the development of hypoparathyroidism. A 70 % PTH drop had a 93.75 NPV for transient hypoparathyroidism. A 12 % calcaemia decay had a 95.7 NPV for hypoparathyroidism. CONCLUSIONS: Hypocalcaemic asymptomatic patients with less than 70 % PTH and 12 % calcaemia decay may be safely discharged without treatment. Symptomatic patients and those with parathyroid grafting should receive calcium and vitamin D.