Pediatric patients on dialysis and their caregivers may need a reality check on what it takes to achieve phosphorus control. Researchers have identified a disconnect between perceived and actual adherence to a low phosphorus diet and phosphate binder therapy.
A team led by Jacob M. Taylor, PhD, RD, of Children’s Mercy Hospital in Kansas City, Missouri, evaluated serum phosphorus levels from 48 children on peritoneal dialysis or hemodialysis who visited the hospital from 2009 to 2013. Using 8 to 12 months of data, they calculated average phosphorus levels for each individual. Children whose levels fell above or below the median by more than 2 standard deviations for their age were noted as having hyperphosphatemia or hypophosphatemia, respectively.
The investigators found a significant relationship between age and phosphorus levels, in accordance with previous research. Teens aged 13 years and older had the highest rate of hyperphosphatemia at 88%, according to results published in the Journal of Renal Nutrition (2016;26:270-275).
Patients and caregivers who reported that phosphorus levels were “controlled” during care planning discussions displayed lower phosphorus than others. Yet, 46% of those patients actually were hyperphosphatemic.
Although 73% of patients reported that following dietary restrictions and taking phosphate binders was “very easy” or “somewhat easy,” 40% of them had hyperphosphatemia. Likewise, 87% of caregivers reported ease with instructions, yet 49% of their children were hyperphosphatemic.
“Our findings, like those of others, suggest that age is the most significant predictor of hyperphosphatemia, with children 13 years of age and older being more likely to have an elevated serum phosphorus level than children under 13,” the researchers commented. “These findings are not surprising given that phosphate binder medications are often particularly unpleasant and require children to not only take medications, but to do so punctually.”
Reducing the phosphorus content of foods may be an area for increased education, the researchers suggested. “Additional attention directed at limiting the intake of phosphorus additives, both from food with limited nutritional benefits and protein-rich foods (while still ensuring adequate protein intake), may help achieve better phosphorus management and patient outcomes,” Dr Taylor and colleagues wrote.
Young children, who probably received low-phosphorus infant formula and toddler meals, were less likely to be hyperphosphatemic. Clinicians may need to be wary of hypophosphatemia in this age group.
Unlike previous research in adult patients, the researchers found no associations between phosphorus levels and the number of daily meals, household income, or family structure. Due to the small number of patients and other study limitations, more research is warranted.
1. Taylor JM, Oladitan L, Degnan A, Henderson S, Dai H, and Warady BA. Psychosocial Factors That Create Barriers to Managing Serum Phosphorus Levels in Pediatric Dialysis Patients: A Retrospective Analysis. J Ren Nutr. 2016 Jul;26(4):270-5. doi:10.1053/j.jrn.2016.02.003.