Height-independent estimation of glomerular filtration rate in children: an alternative to the Schwartz equation.

OBJECTIVE: To compare the diagnostic performance of 2 height-independent equations used to calculate estimated glomerular filtration rate (eGFR), those of Pottel (eGFR-Pottel) and the British Columbia Children's Hospital (BCCH) (eGFR-BCCH), with the commonly used Schwartz equation (eGFR-Schwartz). STUDY DESIGN: We externally validated eGFR-Pottel and eGFR-BCCH in a well-characterized pediatric patient population (n = 152) and compared their diagnostic performance with that of eGFR-Schwartz using Bland-Altman analysis. All patients underwent glomerular filtration rate measurement using the gold standard single-injection inulin clearance method (GFR-inulin). RESULTS: Median GFR-inulin was 92.0 mL/min/1.73 m² (IQR, 76.1-107.4 mL/min/1.73 m²). Compared with GFR-inulin, the mean bias for eGFR-Schwartz was -10.1 mL/min/1.73 m(2) (95% limits of agreement [LOA], -77.5 to 57.2 mL/min/1.73 m(2)), compared with -12.3 mL/min/1.73 m² (95% LOA, -72.6 to 47.9 mL/min/1.73 m(2)) for eGFR-Pottel and -22.1 mL/min/1.73 m² (95% LOA, -105.0 to 60.8 mL/min/1.73 m(2)) for eGFR-BCCH. eGFR-Pottel showed comparable accuracy to eGFR-Schwartz, with 77% and 76% of estimates within 30% of GFR-inulin, respectively. eGFR-BCCH was less accurate than eGFR-Schwartz (66% of estimates within 30% of GFR-inulin; P < .01). CONCLUSION: The performance of eGFR-Pottel is superior to that of eGFR-BCCH and comparable with that of eGFR-Schwartz. eGFR-Pottel is a valid alternative to eGFR-Schwartz in children and could be reported by the laboratory if height data are not available.

Adherence to clinical practice guidelines in the management of children, youth, and young adults with type 1 diabetes--a prospective population cohort study.

OBJECTIVE: To describe adherence to clinical practice guidelines for the treatment of childhood type 1 diabetes and identify associated patient and system level factors. STUDY DESIGN: This prospective cohort study used population-based administrative data to describe individuals aged 1-24 years who had been diagnosed with type 1 diabetes at <20 years of age (1472 unique individuals and 5883 person-years over a 7-year period) living in British Columbia, Canada. The outcome measure was proportion 'at goal,' which was defined as having optimal adherence (3 diabetes-related physician visits/year, 3 hemoglobin A1c (HbA1c) tests/year, 1 glucagon prescription dispensed/year, and appropriate screening for diabetes-related comorbidity [ie, hypothyroidism] and complications [ie, retinopathy and nephropathy]), or good adherence to guidelines (2 diabetes-related physician visits/year, 2 HbA1c tests/year, and appropriate screening for diabetes-related comorbidity and complications). Statistical methods included descriptive statistics and logistic regression modeling. RESULTS: Fifty-four percent person-years had poor adherence to guidelines (<2 diabetes-related physician visits and HbA1c tests/year) and 7.4% had optimal adherence. The proportion of person-years at goal was higher in females vs males (41.0% vs 37.6%; P = .007). Individuals 4-years post-diagnosis of diabetes were 78% less likely to be at goal compared with the year of diagnosis (P < .0001). CONCLUSIONS: The treatment of pediatric type 1 diabetes likely does not meet national and international standards. Future studies should explore facilitators and barriers to adherence to guidelines among health care providers, patients, and families, and whether adherence to guidelines is associated with glycemic control.