Andy N Hoofnagle

Introduction: The validity of a timed urine collection is typically judged by measurement of urine creatinine excretion, but prevailing limits may be unreliable. We sought to empirically derive population-based limits...

Purpose: Maternal thyroid function during pregnancy may influence offspring thyroid function, though relations between maternal and child thyroid function are incompletely understood. We sought to characterize relations between maternal, cord...

Background: The arteriovenous fistula (AVF) is central to haemodialysis treatment, but up to half of surgically created AVF fail to mature. Chronic kidney disease often leads to mineral metabolism disturbances...

Background: Quantifying the variability of biomarkers is important, as high within-person variability can lead to misclassification of individuals. Short-term variability of important markers of vitamin D metabolism is relatively unknown....

Background: Heart failure (HF) is common and is associated with high mortality. We aimed to determine associations of serum parathyroid hormone (PTH) and 25-hydroxyvitamin D (25[OH]D) with incident HF and...

Background: Fibroblast growth factor-23 (FGF-23) is a phosphate regulatory hormone that directly stimulates left ventricular hypertrophy in experimental models. The role of FGF-23 in cardiovascular disease development in the general...

Background: Circulating concentrations of 25-hydroxyvitamin D [25-(OH)D] are used to define vitamin D deficiency. Current clinical 25-(OH)D targets based on associations with intermediate markers of bone metabolism may not reflect...