Background/aims

The objective of this study was to examine health care costs and utilization and the risks of dialysis or mortality among diabetic predialysis chronic kidney disease (CKD) patients with and without secondary hyperparathyroidism (SHPT).

Methods

This retrospective, matched cohort study examined insurance claims from 703 adult diabetic predialysis CKD patients with and without SHPT during a 72-month follow-up period. Annualized estimates of health care service utilization, costs and disease progression to dialysis or death following index CKD diagnosis were compared.

Results

Preindex (baseline) characteristics were similar between the cohorts. Postindex numbers of prescription utilization, outpatient service utilization and hospitalizations were all higher (p < 0.0001) in diabetic CKD patients with SHPT compared to those without SPHT in both unadjusted and adjusted analyses even after multivariate adjustment for known confounders. The rate of progression to dialysis or death was higher for diabetic CKD patients with SHPT compared to those without SPHT. Those with SHPT were at higher risk of requiring dialysis treatment [hazard ratio (HR) = 6.7; 95% confidence interval (CI) = 4.3-10.6] and death (HR = 2.3; 95% CI = 1.1-4.9) compared to those without SHPT.

Conclusion

In diabetic predialysis CKD patients, the presence of SHPT is associated with significantly greater health care resource utilization and costs, and a faster rate of disease progression.

Background

The efficacy of 25-hydroxyvitamin D (25[OH]D) supplementation versus vitamin D receptor activators for the treatment of secondary hyperparathyroidism (SHPT) in patients with chronic kidney disease (CKD) stages 3 or 4 and vitamin D deficiency is unclear.

Study design

Randomized controlled trial.

Setting & participants

80 patients with CKD stages 3 or 4, 25(OH)D level <30 ng/mL, and SHPT in a single medical center.

Intervention

Ergocalciferol, 50,000 units, titrated to achieve serum levels ≥30 ng/mL versus paricalcitol, 1 or 2 μg/d, for 16 weeks.

Outcomes

The occurrence of 2 consecutive parathyroid hormone (PTH) levels decreased by at least 30% from baseline. All analyses were intention to treat.

Results

Baseline characteristics in the 2 groups were similar. 21 patients (53%) on paricalcitol and 7 patients (18%) on ergocalciferol treatment achieved the primary outcome measure (P = 0.002). After 16 weeks, PTH levels did not decrease significantly in patients receiving ergocalciferol, but were decreased significantly in those treated with paricalcitol (mean estimate of between-group difference over 16 weeks of therapy, 43.9 pg/mL; 95% CI, 11.2-76.6; P = 0.009). Serum 25(OH)D levels increased significantly after 16 weeks in only the ergocalciferol group, but not the paricalcitol group (mean estimate of between-group difference over 16 weeks of therapy, 7.08 ng/mL; 95% CI, 4.32-9.85; P < 0.001). Episodes of hyperphosphatemia and hypercalcemia were not significantly different between the 2 groups.

Limitations

Lack of blinding and use of surrogate end points.

Conclusions

Paricalcitol is more effective than ergocalciferol at decreasing PTH levels in patients with CKD stages 3 or 4 with vitamin D deficiency and SHPT.