Incidence and Risk Factors of Obesity in Childhood Solid-Organ Transplant Recipients.

BACKGROUND: Obesity is a significant public health concern; however, the incidence post solid-organ transplantation is not well reported. METHODS: This study determined the incidence and risk factors of obesity among pediatric solid-organ transplant recipients (heart, lung, liver, kidney, multiorgan) at The Hospital for Sick Children (2002-2011), excluding prevalent obesity. Follow-up occurred from transplantation until development of obesity, last follow-up, or end of study. Incidence of obesity was determined overall, by baseline body mass index, and organ group. Risk factors were assessed using Cox proportional-hazards regression. RESULTS: Among 410 (55% male) children, median transplant age was 8.9 (interquartile range [IQR]: 1.0-14.5) years. Median follow-up time was 3.6 (IQR: 1.5-6.4) years. Incidence of obesity was 65.2 (95% confidence interval [CI]: 52.7-80.4) per 1000 person-years. Overweight recipients had a higher incidence, 190.4 (95% CI: 114.8-315.8) per 1000 person-years, than nonoverweight recipients, 56.1 (95% CI: 44.3-71.1). Cumulative incidence of obesity 5-years posttransplant was 24.1%. Kidney relative to heart recipients had the highest risk (3.13 adjusted hazard ratio [aHR]; 95% CI: 1.53-6.40) for obesity. Lung and liver recipients had similar rates to heart recipients. Those with higher baseline body mass index (z-score; 1.72 aHR; 95% CI: 1.39-2.14), overweight status (2.63 HR; 95% CI: 1.71-4.04), and younger transplant age (y; 1.18 aHR; 95% CI: 1.12-1.25) were at highest risk of obesity. Higher cumulative steroid dosage (per 10 mg/kg) was associated with increased risk of obesity after adjustment. CONCLUSIONS: Among all transplanted children at The Hospital for Sick Children, 25% developed obesity within 5-years posttransplant. Kidney recipients, younger children, those overweight at transplant, and those with higher cumulative steroid use (per 10 mg/kg) were at greatest risk. Early screening and intervention for obesity are important preventative strategies.

Impact of fill volume on ultrafiltration with icodextrin in children on chronic peritoneal dialysis.

BACKGROUND: Icodextrin is a solution of glucose polymers developed to provide sustained ultrafiltration over an extended dwell. Our aim was to determine whether or not fill volume with icodextrin contributes to the ability to achieve ultrafiltration in children. METHODS: The charts of all children on chronic peritoneal dialysis between January 2000 and July 2014 were screened for the use of an icodextrin day dwell. Data were extracted from the electronic chart and the HomeChoice™ Pro card and corrected for body surface area (BSA). RESULTS: Fifty children had an icodextrin day dwell. A linear correlation was found between the daytime fill volume and net ultrafiltration (p < 0.001). More ultrafiltration was achieved with a fill volume above 550 ml/m(2) BSA (107 ± 75 ml/m(2) BSA) than with smaller fill volumes (-8 ± 99 ml; p = 0.004). Ultrafiltration was achieved in 88 % of children with a fill volume above 550 ml/m(2) BSA versus only 44 % of patients with a smaller fill volume (p = 0.001). Icodextrin was well tolerated. CONCLUSIONS: Our observations reveal that the larger the fill volume the higher the likelihood of achieving ultrafiltration with icodextrin and suggest that a minimum day dwell volume of 550 ml/m(2) BSA seems to facilitate ultrafiltration in children. To our knowledge this is the largest study addressing ultrafiltration with icodextrin in children.

The rationale and design of Insight into Nephrotic Syndrome: Investigating Genes, Health and Therapeutics (INSIGHT): a prospective cohort study of childhood nephrotic syndrome.

BACKGROUND: Nephrotic syndrome is one of the most commonly diagnosed kidney diseases in childhood and its progressive forms can lead to chronic kidney disease (CKD) and/or end-stage renal disease (ESRD). There have been few longitudinal studies among a multi-ethnic cohort to determine potential risk factors influencing disease susceptibility, treatment response, and progression of nephrotic syndrome. Temporal relationships cannot be studied through cross-sectional study design. Understanding the interaction between various factors is critical to developing new strategies for treating children with kidney disease. We present the rationale and the study design of a longitudinal cohort study of children with nephrotic syndrome, the Insight into Nephrotic Syndrome: Investigating Genes, Health and Therapeutics (INSIGHT) study. The specific aims are to determine: 1) socio-demographic, environmental, and genetic factors that influence disease susceptibility; 2) rates of steroid treatment resistance and steroid treatment dependence, and identify factors that may modify treatment response; 3) clinical and genetic factors that influence disease susceptibility and progression to CKD and ESRD; and 4) the interaction between the course of illness and socio-demographic, environmental, and clinical risk factors. METHODS/DESIGN: INSIGHT is a disease-based observational longitudinal cohort study of children with nephrotic syndrome. At baseline, participants complete questionnaires and provide biological specimen samples (blood, urine, and toenail clippings). Follow-up questionnaires and repeat biological specimen collections are performed annually for up to five years. DISCUSSION: The proposed cohort will provide the structure to test various risk factors predicting or influencing disease susceptibility, treatment response, and progression to CKD among children with nephrotic syndrome. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT01605266.