Changing trends in the referral patterns of pediatric nephrology patients.

This study investigates the changing referral patterns of young patients to a tertiary pediatric nephrology center with a well-defined catchment area over two consecutive 8.5-year periods. We paid special attention to the known increase of obesity and diabetes mellitus in childhood. Demographic data (site of residence, height, weight, gender and renal diagnosis) were collected on 6,154 children aged 0-19 years, referred as in- and outpatients to the Children's Hospital of Eastern Ontario for nephrological work-up. Body mass index (BMI) Z-scores were calculated on the basis of data from the National (USA) Center for Health Statistics (2000). In 6,124 (99.5%) patients a final renal diagnosis could be made, allowing calculation of the incidence of a variety of renal diseases in pediatric patients, data that are not readily available. BMI increased significantly over the years, with a Z-score that rose from a median of +0.20 to +0.32 in the two 8.5-year study periods (p<0.0001). The increase in obesity coincided with a significant increase in the incidence of chronic renal insufficiency (CRI). The combined incidence of CRI and end stage renal disease rose from 0.994 to 2.334 per 100,000 children per year (p=0.0014). This study provides new information on the (changing) pattern of pediatric renal disease over almost two decades. Pediatric renal patients became progressively overweight and showed an increase in the incidence of CRI. This is the first time that this phenomenon, well known in adults, has been observed in the pediatric age group.