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Lead-time bias in studies of cinacalcet prescriptions

Marie Evans1, Carl Michael Fored

  • 1Division of Renal Medicine, Department of Clinical Science Intervention and Technology, Karolinska University Hospital, Huddinge, Stockholm, Sweden. Marie.Evans@ki.se

Kidney International
|September 1, 2010
PubMed

Insights

Higher serum phosphate, calcium, and parathyroid hormone levels are linked to cardiovascular death. Cinacalcet may improve mortality in hemodialysis patients, but observational study biases require cautious interpretation.

Area of Science:

  • Nephrology
  • Cardiology
  • Clinical Pharmacology

Background:

  • Elevated serum phosphate, calcium, and parathyroid hormone are associated with cardiovascular mortality.
  • Secondary hyperparathyroidism is common in hemodialysis patients.
  • Cinacalcet is a calcimimetic agent used to treat secondary hyperparathyroidism.

Purpose of the Study:

  • To discuss the potential biases in observational studies examining the effect of cinacalcet on mortality.
  • To highlight the need for cautious interpretation of findings from observational research.

Main Methods:

  • Review of observational studies on cinacalcet and mortality.
  • Discussion of potential confounding factors and biases in observational data.
  • Analysis of the association between cinacalcet, mineral metabolism, and cardiovascular outcomes.

Main Results:

  • Observational data suggest cinacalcet treatment is associated with improved all-cause and cardiovascular mortality in hemodialysis patients.
  • Potential biases, such as confounding by indication and unmeasured confounders, may influence these findings.
  • The observed mortality benefits require careful consideration due to the limitations of observational study designs.

Conclusions:

  • While cinacalcet shows promise in reducing mortality in hemodialysis patients with secondary hyperparathyroidism, observational data must be interpreted with caution.
  • Further investigation using robust study designs is needed to confirm these findings.
  • Understanding and mitigating bias are crucial for accurate assessment of therapeutic interventions.

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