Bridging the Gaps in Management of Chronic Kidney Disease – Mineral Bone Disorder: Insights from the China Dialysis Outcomes and Practice Patterns Study Phase 5

0
0
0

Bridging the Gaps in Management of Chronic Kidney Disease-Mineral Bone Disorder: Insights from the China Dialysis Outcomes and Practice Patterns Study Phase 5

The China Dialysis Outcomes and Practice Patterns Study (DOPPS) Phase 5, conducted between 2012 and 2015, offers critical insights into disparities in the management of chronic kidney disease-mineral bone disorder (CKD-MBD) among hemodialysis (HD) patients in China compared to 20 other countries. Despite significant progress in establishing national dialysis registries, such as the Chinese National Renal Data System (CNRDS), challenges persist in the standardization of laboratory monitoring and therapeutic interventions. The China DOPPS study, while not fully representative of China’s entire HD population due to its focus on metropolitan areas (Beijing, Guangzhou, Shanghai), provides a snapshot of practice patterns that highlight urgent areas for improvement.

Study Design and Population Characteristics

The study enrolled 1,186 randomly selected HD patients from 45 facilities across three major Chinese cities. Notably, the cohort differed demographically from international counterparts: Chinese HD patients were younger and less frequently affected by diabetic kidney disease. Dialysis vintage (time on dialysis) was shorter in China compared to Japan but aligned with global averages. These differences emphasize the need for tailored management strategies that account for China’s unique patient demographics.

Disparities in Parathyroid Hormone (PTH) Management

Secondary hyperparathyroidism (PTH >600 pg/mL) was significantly more prevalent in China (19%) than in other DOPPS countries (0–15%), despite genetic predispositions to lower PTH levels in Asian populations. Paradoxically, Chinese facilities reported stricter PTH upper limits (300–399 pg/mL) compared to North America and Europe, though similar to Japan. However, PTH monitoring frequency in China lagged behind global practices, with only 3.2% of patients tested monthly versus 15.1%–23.2% elsewhere. This discrepancy highlights a critical gap between clinical targets and real-world monitoring.

Therapeutic interventions for PTH control were suboptimal. Active vitamin D prescriptions showed no correlation with PTH levels, and cinacalcet use was rare (2% in China vs. 16%–24% globally). Low cinacalcet availability, potentially due to cost or regulatory barriers, likely contributed to poor PTH control. The study underscores the necessity for enhanced medication accessibility and protocol-driven adjustments based on biochemical markers.

Hyperphosphatemia: Dietary and Dialysis Factors

Severe hyperphosphatemia (phosphorus >7 mg/dL) affected 27% of Chinese patients, starkly higher than the 7%–10% prevalence in other countries. Despite lower dietary phosphorus intake in traditional Chinese diets, processed foods and medications likely exacerbated hyperphosphatemia. Facility directors in China endorsed stricter phosphorus targets (≤5.5 mg/dL), similar to Europe but lower than Japan. However, monthly phosphorus testing occurred in only 14.9% of Chinese patients versus >70% internationally.

Dialysis adequacy metrics further contextualized these findings. Chinese patients exhibited lower standardized Kt/V (a measure of dialysis efficacy) compared to global averages, potentially due to shorter session durations and variable dialyzer use. Although blood flow rates in China (averaging 250–300 mL/min) exceeded Japanese standards, they remained below North American and European practices. Optimizing dialyzer technology—including high-flux filters or hemodiafiltration—and individualizing session lengths could improve phosphorus clearance and reduce interdialytic accumulation.

Hypocalcemia and Calcium Management

Hypocalcemia (albumin-adjusted calcium <8.4 mg/dL) was prevalent in China, with 15.1% of patients tested monthly versus 72.2%–93.3% globally. Despite higher dialysate calcium concentrations (≥3.0 mEq/L in 73% of facilities), average serum calcium levels (9.12 mg/dL) remained lower than those in North America and Europe. This paradox suggests inefficiencies in calcium balance management, possibly linked to underuse of calcium-based phosphate binders or vitamin D analogs.

Phosphate Binder Utilization and Therapeutic Gaps

Phosphate binder prescriptions in China (59% of patients) lagged behind global standards, particularly for non-calcium-based binders. For example, sevelamer and lanthanum use was minimal compared to international rates. Cost constraints and limited availability likely restricted access to newer agents, perpetuating reliance on calcium-based binders and elevating risks of vascular calcification. The study advocates for expanded insurance coverage and formulary inclusions to align Chinese practices with global trends.

Parathyroidectomy: An Underutilized Intervention

Parathyroidectomy rates were exceptionally low in China, despite their proven efficacy in reducing PTH, phosphorus, and calcium levels in refractory cases. Cultural perceptions, surgical accessibility, and lack of standardized referral pathways may contribute to underutilization. Increasing awareness and developing clinical guidelines for surgical intervention could mitigate complications of severe CKD-MBD.

Temporal Context and Progress Since 2012–2015

The study’s reliance on data from 2012–2015 necessitates caution in extrapolating findings to current practice. Recent improvements, such as wider availability of non-calcium-based binders, cinacalcet, and vitamin D analogs, may have narrowed gaps in CKD-MBD management. However, persistent regional disparities—particularly in rural versus urban care—underscore the need for nationwide quality initiatives.

Toward Standardized Care and China-Specific Guidelines

The China DOPPS Phase 5 study calls for urgent action to harmonize CKD-MBD management with global standards. Key recommendations include:

  1. Enhanced Monitoring Protocols: Mandate monthly testing for PTH, phosphorus, and calcium to enable data-driven treatment adjustments.
  2. Medication Access: Improve affordability and availability of non-calcium-based phosphate binders, cinacalcet, and vitamin D analogs through policy reforms and insurance expansions.
  3. Dialysis Optimization: Invest in high-efficiency dialyzers, hemodiafiltration, and individualized session protocols to enhance solute clearance.
  4. Surgical Referral Pathways: Establish guidelines for parathyroidectomy in refractory hyperparathyroidism.
  5. National Guidelines: Develop China-specific CKD-MBD guidelines incorporating DOPPS data, addressing genetic and dietary factors unique to Chinese patients.

Conclusion

The China DOPPS Phase 5 study reveals systemic gaps in CKD-MBD management, from inadequate biochemical monitoring to therapeutic inertia. Bridging these disparities requires multisectoral collaboration among policymakers, clinicians, and researchers. By prioritizing standardized care pathways, expanding treatment access, and leveraging real-world data, China can achieve parity in HD outcomes and set a benchmark for resource-limited settings globally.

doi.org/10.1097/CM9.0000000000000497

Was this helpful?

0 / 0