As suggested by its American brand name (Sensipar), the calcimimetic cinacalcet sensitizes the parathyroid cells to the extracellular calcium signal, suppressing parathyroid hormone (PTH) release and synthesis and preventing parathyroid cell proliferation. This primary PTH suppression decreases the release of calcium and phosphate from bone without increasing intestinal absorption of calcium and phosphate. Therefore cinacalcet decreases the risk of hypercalcemia and hyperphosphatemia in contrast to 1alpha-OH vitamin D derivatives. Compared with calcium-containing oral phosphate binder (OPB), it increases the risk of hypocalcemia and may decrease the PTH-mediated phosphaturia in predialysis patients. This justifies its combined use with calcium-containing OPB in order to prevent hypocalcemia and enhance the hypophosphatemic effect of the latter, while improving PTH suppression. The National Kidney Foundation (NKF) Kidney Disease Outcomes Quality Initiative (K/DOQI) has recommended restriction of supplemental elemental calcium to 1.5 g/day, a recommendation that we believe should be revised. No pathophysiologic or randomized trial data have yet evidenced the absolute necessity for systematically using 1alpha-OH vitamin D derivatives and noncalcium-containing OPB rather than higher doses of calcium-containing OPB alone in uremic patients without vitamin D insufficiency. In patients with hyperparathyroidism as severe as in the "Treat to Goal Study," the Durham study showed that a calcium carbonate dose more than three times the K/DOQI limit could decrease PTH into the recommended range, with the advantage of a lower calcium-phosphate product compared with the combination of calcitriol and noncalcium OPB. Besides the efficient PTH suppression associated with lower calcium-phosphate product and a good gastrointestinal tolerance, long-term data suggest that cinacalcet may decrease the risk of parathyroidectomy and fracture, while high bone turnover lesions are improved. However, no long-term data on bone mineral density and cardiovascular calcification and complications are yet available. Such studies, along with those comparing cinacalcet and 1alpha-OH vitamin D-based approaches to hyperparathyroidism, are needed.

In the CHOICE dialysis cohort, Melamed et al. 1 found in their lagged analysis that intact PTH levels o76 pg/ml were associated with a 35% lower mortality compared to levels of 160-308 pg/ml. In order to appropriately discuss this observation in relation with National Kidney Foundation-Kidney Disease Outcomes Quality Initiative optimal intact parathyroid hormone (PTH) of 150-300 pg/ml, we think that these figures have to be first corrected by the 50% lower median bias induced by the Diasorin intact PTH assay when compared with the Nicholls Allegro assay to which Kidney Disease Outcomes Quality Initiative is referring. 2 This means that Allegro PTH o150 pg/ml would be associated with a better survival than PTH of 300-620 pg/ml. This certainly challenges the National Kidney Foundation-Kidney Disease Outcomes Quality Initiative recommendation 3 of preventing a PTH o150 pg/ml. This is not too surprising as this recommendation was just based on claims of a few authors (cited by Melamed) who pointed out a link between low bone turnover and mortality. Furthermore, this recommendation disregarded the results of the bone histomorphometric study meta-analysis suggesting that Allegro PTH o60 pg/ml best predicted low bone turnover. It should be, however, noted that the observation by Melamed et al. is in agreement with the most recent prognostic evaluation of PTH by Block et al., 4 which, owing to better adjustment with other comorbidities (specially malnutrition), did not find anymore a higher mortality with Allegro PTH o150 pg/ml, but found a higher mortality when PTH was 4600 pg/ml.

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declared that, 'The evidence is here,' in reference to a Wyeth product. These bands convey the impression of a connection between scientific evidence for the products, the pharmaceutical company, and the independent academic journal.The November editions of the Journal of the American Society of Nephrology, American Journal of Kidney Diseases, and Kidney International contained 30, 19, and 13 advertisements, respectively. Of these three journals, the November issue of Kidney International actually had the lowest number of large page advertisements. However, unlike these other journals, advertisements in Kidney International were not limited to the pages preceding and following the contents of the journal but were interspersed. These observations raise the question of whether journals face a trade-off between running a larger number of appropriate advertisements or a lesser number of (presumably more lucrative) inappropriate advertisements in order to cover costs.To avoid risking the loss of respect of its readers, we urge Kidney International to eliminate practices that blur the boundary between academic pursuits and advertising. If we are incapable of self-regulation, it will only be a matter of time before the government steps in to control advertising practices in medical journals.

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