Development and utility of a multi-dimensional grid to assess individual mineral metabolism control in hemodialysis patients: A potential aid for therapeutic decision making?

A grid was developed to evaluate control of serum calcium, phosphate, and parathyroid hormone levels in hemodialysis patients, based on guideline recommendations (National Kidney Foundation Kidney Disease Outcomes Quality Initiative and Canadian Society of Nephrology), and its face validity was examined in a representative sample of Canadian patients. A retrospective chart review was undertaken in hemodialysis patients from 7 Canadian units. Patients >18 years, on hemodialysis for > or =12 months, and > or =3 parathyroid hormone levels measured > or =1 month apart were included. The grid classified mineral metabolism control as optimal, suboptimal, or poor (mean of 3 measurements). Medication use, hospitalization, and Emergency Department visits were evaluated in relation to grid occupancy. A second comparative analysis of grid occupancy was undertaken on prevalent hemodialysis cases in British Columbia in 2008. Data from 268 patients (mean age 62.3 years) were analyzed. Using National Kidney Foundation Kidney Disease Outcomes Quality Initiative guidelines, 17.5%, 28.8%, and 53.7% of patients had optimal, suboptimal, and poor control, respectively, of all 3 parameters (calcium, phosphate, and parathyroid hormone). Using Canadian Society of Nephrology criteria, optimal, suboptimal, and poor control rates were 6.3%, 4.2%, and 89.5%, respectively. Poor control was a possible or a probable cause of hospitalization or Emergency Department attendance in 8 patients. Data from British Columbia in 2008 (n=1858) show optimal, suboptimal, and poor control rates of 15.8%, 24.5%, and 59.7%, respectively. Poor mineral metabolism control among Canadian hemodialysis patients is not showing improvement. The therapeutic grid is a valid tool and may help guide therapeutic decisions, quality control initiatives, and patient counseling. http://www.ukidney.com/bone-and-mineral-metabolism-resource.