Jaar, Bernard G.

Key Points Serum glycerol-3-phosphate (G3P) levels were significantly associated with higher fibroblast growth factor 23 levels in ESKD. Pathway and mediation analyses identified the pentose phosphate pathway as the top mediator of the relationship between serum G3P and fibroblast growth factor 23. The role of G3P in ESKD provides new insights into potential therapeutic targets for CKD-mineral and bone disorder. Background Fibroblast growth factor 23 (FGF23) is a key regulator of mineral metabolism that is independently associated with mortality in patients with ESKD. Glycerol-3-phosphate (G3P), a byproduct of glycolysis that can be derived from injured kidneys, stimulates FGF23 production. We aimed to determine if serum G3P is associated with FGF23 levels in patients with ESKD and identify potential molecular pathways that mediate their relationship. Methods We conducted a cross-sectional study of 99 nondiabetic patients with ESKD on hemodialysis. We used linear regression to examine the association between G3P terciles and log-transformed C-terminal FGF23 levels, adjusting for demographics, coronary artery disease, serum calcium, phosphorus, and parathyroid hormone. Mann–Whitney U tests compared 247 serum metabolite levels between the first and third FGF23 terciles; significant metabolites ( P < 0.01) were selected for pathway enrichment analyses. Top pathway scores were used in mediation analyses. Results The median age of participants was 54 years (interquartile range [IQR], 44–63), 38% were women, 71% self-identified as Black, and 27% had coronary artery disease. The median FGF23 level was 777 (interquartile range, 222–1310) RU/ml. In adjusted analyses, compared with participants with the lowest G3P tercile, those with the highest G3P tercile had a 95% higher FGF23 level (95% Confidence Interval, 6% to 260%; P = 0.04). Of the 27 metabolites significantly associated with FGF23 levels, pathway enrichment analysis identified the pentose phosphate pathway as the top hit (impact score=0.33, false discovery rate-adjusted P value = 0.01). The pentose phosphate pathway mediated the relationship between G3P and FGF23, resulting in a 62% change in the β coefficient. Conclusions In nondiabetic patients with ESKD on hemodialysis, serum G3P positively correlated with serum C-terminal FGF23, and this relationship was mediated by the pentose phosphate pathway. Exploring the pentose phosphate pathway could yield critical mechanistic insights into the regulation of FGF23, enhancing our understanding of its broader biologic functions.

AbstractAs medical advances are made in the care of persons with chronic illnesses including those with end‐stage renal disease (ESRD), patients are not only experiencing increasing life expectancy but also bearing the burden of illness and treatment for a longer duration of time. With this in mind, it is increasingly important for health care providers to pay close attention to their individual patient's perceptions of their health, fitness, life satisfaction, and well‐being. This assessment of Health‐Related Quality of Life (HRQOL) also includes an evaluation of the patient's level of satisfaction with treatment, outcome, and health status, also taking into account their perspective on future prospects. In addition to improving patient–provider communication by helping in the identification and prioritization of problems, it is important to note that high HRQOL has been shown to be associated with better medical outcomes, including reduction in hospitalizations and death. In this review, we outline several validated tools that are used to quantitatively measure HRQOL in the ESRD population and incorporate these instruments in a review of specific, evidence‐based measures by which we can measurably improve health‐related quality of life in dialysis patients.