Relaci�n entre hiperinsulinemia, disfunci�n diast�lica e hipertrofia del ventr�culo izquierdo en pacientes con hipertensi�n arterial sist�mica

Background: Hypertension is the main independent cardiovascular risk factor. However, there are additional factors that induce organic damage. Aim: To assess the association between hyperinsulinemia, ventricular hypertrophy and left ventricular diastolic function. Patients and Methods: Seventy-four patients aged 30 to 65 years, with mild or moderate systemic hypertension, with overweight or mild obesity and normal glucose tolerance curve (GTC), were studied. Serum insulin was measured during GTC. The maximum levels of insulin and glucose were observed 60 minutes after the oral glucose load and they were expressed as rG/1. Patients were stratified in three groups according to their glucose and insulin fasting levels (I0) and post-glucose challenge levels (rG/I): Group 1 (normoinsulinemic patients) I0 &lt;17 mU/mL and rG/I >2 (2.45+0.4). Group 2 (post-prandial hyperinsulinemic patients) I0 &lt;17 mU/mL and rG/I <2&#62; 1 (1.34+0.3). Group 3 (persistently hyperinsulinemic patients) I0 >17 mU/mL and &lt;1 (0.7+0.3). Left ventricular mass and its diastolic function were measured by Doppler echocardiography. Results: No differences in blood pressure or age were observed between groups. There was a negative correlation between ventricular mass and rG/1 (r =-0.282, p =0.015). Left ventricular diastolic dysfunction was significantly more deteriorated in group 3, as compared with group 1 (p <0.001 ANOVA). There was a significant correlation between g/GI and diastolic dysfunction (r =0.232 p =0.047). Conclusions: Fasting, post challenge hyperinsulinemia and a rG/I &lt;1 are associated with higher ventricular mass and left ventricular diastolic dysfunction, independent of blood pressure and age (Rev Méd Chile 2007; 135: 1125-31

Radiation dose from medical imaging in end stage renal disease patients: a Nationwide Italian Survey

Background and objectives: End stage renal disease (ESRD) patients are exposed to the risk of ionizing radiation during repeated imaging studies. The variability in diagnostic imaging policies and the accompanying radiation doses across various renal units is still unknown. We studied this variability at the centre level and quantified the associated radiation doses at the patient level. Methods: Fourteen Italian nephrology departments enrolled 739 patients on haemodialysis and 486 kidney transplant patients. The details of the radiological procedures performed over one year were recorded. The effective doses and organ doses of radiation were estimated for each patient using standardized methods to convert exposure parameters into effective and organ doses RESULTS: Computed tomography (CT) was the major contributor (> 77%) to ionizing radiation exposure. Among the haemodialysis and kidney transplant patients, 15% and 6% were in the high ( 65 20 mSv per year) radiation dose groups, respectively. In haemodialysis patients, the most exposed organs were the liver (16 mSv), the kidney (15 mSv) and the stomach (14 mSv), while the uterus (6.2 mSv), the lung (5.7 mSv) and the liver (5.5 mSv) were the most exposed in kidney transplant patients. The average cumulative effective dose (CED) of ionizing radiation among centres in this study was highly variable both in haemodialysis (from 6.4 to 18.8 mSv per patient-year; p = 0.018) and even more so in kidney transplant (from 0.6 to 13.7 mSv per patient-year; p = 0.002) patients. Conclusions: Radiation exposure attributable to medical imaging is high in distinct subgroups of haemodialysis and transplant patients. Furthermore, there is high inter-centre variability in radiation exposure, suggesting that nephrology units have substantially different clinical policies for the application of diagnostic imaging studies