A new approach to predicting mortality in dialysis patients using sociodemographic features based on artificial intelligence.

One of the main problems that affect patients in dialysis therapy who are on the waiting list to receive a kidney transplant is predicting their survival time if they do not receive a transplant. This paper proposes a new approach to survival prediction based on artificial intelligence techniques combined with statistical methods to study the association between sociodemographic factors and patient survival on the waiting list if they do not receive a kidney transplant. This new approach consists of a first stage that uses the clustering techniques that are best suited to the data structure (K-Means, Mini Batch K-Means, Agglomerative Clustering and K-Modes) used to identify the risk profile of dialysis patients. Later, a new method called False Clustering Discovery Reduction is performed to determine the minimum number of populations to be studied, and whose mortality risk is statistically differentiable. This approach was applied to the OPTN medical dataset (n = 44,663). The procedure started from 11 initial clusters obtained with the Agglomerative technique, and was reduced to eight final risk populations, for which their Kaplan-Meier survival curves were provided. With this result, it is possible to make predictions regarding the survival time of a new patient who enters the waiting list if the sociodemographic profile of the patient is known. To do so, the predictive algorithm XGBoost is used, which allows the cluster to which it belongs to be predicted and the corresponding Kaplan-Meier curve to be associated with it. This prediction process is achieved with an overall Multi-class AUC of 99.08 %.

Mineral metabolism disorders, vertebral fractures and aortic calcifications in stable kidney transplant recipients: The role of gender (EMITRAL study) / Alteraciones del metabolismo mineral, fracturas vertebrales, y calcificaciones aórticas en receptores estables de trasplante renal: papel del género (estudio EMITRAL)

Antecedentes y objetivos: La relación entre las alteraciones del metabolismo mineral, las fracturas óseas y las calcificaciones vasculares en receptores de un trasplante renal no han sido establecidas. Método: Realizamos un estudio transversal en 727 receptores estables procedentes de 28 centros de trasplante españoles. Se determinaron de manera centralizada los parámetros del metabolismo mineral; también se centralizó la semicuantificación de las fracturas vertebrales y de las calcificaciones de la aorta abdominal. Resultados: La deficiencia de vitamina D (25OHD3 < 15ng/ml) fue más frecuente en mujeres y en los estadios CKD-T I-III (29,6 vs. 44,4%; p=0,003). La relación inversa y significativa observada entre los niveles de 25OHD3 y PTH fue modificada por el género de tal manera que la pendiente fue mayor en las mujeres que en los hombres (p=0,01). Un 15% de los receptores mostró alguna fractura vertebral (VFx) con un grado de deformidad ≥2. Los factores relacionados con la VFx diferían en función del género: en los hombres, la edad (OR: 1,04; IC 95%: 1,01-1,06) y el tratamiento con CsA (OR: 3,2; IC 95: 1,6-6,3); en las mujeres la edad (OR: 1,07; IC 95%: 1,03-1,12) y los niveles de PTH (OR per 100pg/ml increase: 1,27; IC 95%: 1,043-1,542). Las calcificaciones de la aorta abdominal fueron comunes (67,2%) y se relacionaron con los factores de riesgo clásicos, pero no con los parámetros del metabolismo mineral. Conclusiones: La deficiencia de vitamina D es más frecuente en las mujeres receptoras de un trasplante renal y en los estadios más tempranos de la CKD-T, y es un factor que contribuye al desarrollo de hiperparatiroidismo secundario. Las VFx prevalentes están relacionadas con unos niveles más elevados de PTH solamente en las mujeres (AU)

Background and objectives: The relationship between mineral metabolism disorders, bone fractures and vascular calcifications in kidney transplant recipients has not been established. Method: We performed a cross-sectional study in 727 stable recipients from 28 Spanish transplant clinics. Mineral metabolism parameters, the semi-quantification of vertebral fractures and abdominal aortic calcifications were determined centrally. Results: Vitamin D deficiency (25OHD3 < 15 ng/ml) was more common in female recipients at CKD-T stages I–III (29.6% vs 44.4%; p=0.003). The inverse and significant correlation between 25OHD3 and PTH was gender-specific and women exhibited a steeper slope than men (p=0.01). Vertebral fractures (VFx) with deformity grade ≥2 were observed in 15% of recipients. Factors related to VFx differed by gender; in males, age (OR 1.04; 95% CI 1.01-1.06) and CsA treatment (OR: 3.2; 95% CI: 1.6-6.3); in females, age (OR 1.07; 95% CI: 1.03-1.12) and PTH levels (OR per 100 pg/ml increase: 1.27; 95% CI: 1.043-1.542). Abdominal aortic calcifications were common (67.2%) and related to classical risk factors but not to mineral metabolism parameters. Conclusions: Vitamin D deficiency is more common among female kidney transplant recipients at earlier CKD-T stages, and it contributes to secondary hyperparathyroidism. Prevalent vertebral fractures are only related to high serum PTH levels in female recipients (AU)

Transplant strategies for diabetic renal patients.

The strict control of glycaemia in the diabetic patient prevents severe long-term complications of diabetes. The most effective physiological method to control glycaemia in the type 1 diabetes patient is pancreas or pancreatic islet transplant. However, these types of transplants require chronic immunosuppressant treatment that leads to short and long term complications and are reserved for type 1 diabetic patients with life threatening complications (frequent unexplained ketoacidosis or hypoglycaemias). With regards to type 1 diabetics with end-stage nephropathy, simultaneous pancreas-kidney transplant has excellent results and makes it possible for the patient to be insulin and dialysis free. If vascular complications, especially coronary disease, make it impossible to perform a simultaneous pancreas-kidney transplant, kidney transplant alone will be indicated and, in the future, the patient may have access to the transplant of pancreatic islets when the technique is perfected. Type 1 diabetic patients who receive a living or cadaver kidney transplant, and later a pancreatic transplant show excellent results. Type 2 diabetics, in whom pancreas transplant is not indicated, as they do not have a total deficit of insulin, can have access to a kidney transplant if they reach end-stage nephropathy in spite of their more advanced age, as long as their vascular disease allows it. Transplant of cadaver islets is beginning to provide good results, thanks to new immunosuppressant protocols. This procedure does not require surgery, the islets being implanted into the liver by infusion through the vena porta. Obtaining islets from embryonic or adult tissue stem cells, although in an experimental phase, could be a reality in the near future.