TY - JOUR
T1 - Variation in oral calcitriol response in patients with stages 3-4 CKD
AU - Shoben, Abigail B.
AU - Levin, Gregory
AU - De Boer, Ian H.
AU - Yeung, Catherine
AU - Watnick, Suzanne
AU - Ayers, Ernie
AU - Kestenbaum, Bryan
N1 - Funding Information:
Support: This study was supported by National Institutes of Health grants R01 HL084443 and R01 AG 027002 . This article is the result of work supported by resources from the VA Puget Sound Health Care System, Seattle, WA.
PY - 2012/5
Y1 - 2012/5
N2 - Background: Oral calcitriol decreases parathyroid hormone (PTH) concentrations in patients who have chronic kidney disease (CKD); however, treatment response is highly variable. We evaluated whether patient characteristics affect the PTH response to oral calcitriol in nondialysis patients with CKD in a clinic-based setting. Study Design: Cohort study. Setting & Participants: This study included 379 new oral calcitriol users in the Veterans' Affairs Northwest Health Network. All had stages 3-4 CKD, hyperparathyroidism, and a serum PTH measurement before and 1-6 months after initiating oral calcitriol therapy. Predictors: Patient-level characteristics hypothesized to affect calcitriol response: race, body size, concurrent medications, and kidney function. Outcomes: Relative decrease in serum PTH concentration after starting oral calcitriol therapy. Measurements: Data were abstracted from the Veterans' Affairs Northwest Health Network (VISN 20) Data Warehouse, which includes electronic pharmacy and laboratory records. Results: Mean estimated glomerular filtration rate was 30 mL/min/1.73 m 2 and mean initial PTH concentration was 199 pg/mL. Regular- (0.25 μg/d) and low-dose (<0.25 μg/d) oral calcitriol were associated with on average 23% and 13% relative decreases in serum PTH concentrations, respectively. After adjustment for calcitriol dosage, initial PTH concentration, and time to follow-up measurement, African American race was associated with a blunted calcitriol response (geometric mean final PTH value, 26% higher; 95% CI, 8%-47%). Serum albumin concentration <3.5 g/dL also was associated with a diminished calcitriol response (geometric mean final PTH, 19% higher; 95% CI, 6%-35%). Although numbers were small, concurrent use of benzodiazepines and nonactivated vitamin D supplements was associated with a significantly greater PTH response. Limitations: Clinic-based study is limited by the availability of PTH measurements after starting calcitriol therapy. Study of a predominantly older male population. Conclusions: In patients with stages 3-4 CKD, African American race and low serum albumin level are associated with a diminished PTH response to oral calcitriol.
AB - Background: Oral calcitriol decreases parathyroid hormone (PTH) concentrations in patients who have chronic kidney disease (CKD); however, treatment response is highly variable. We evaluated whether patient characteristics affect the PTH response to oral calcitriol in nondialysis patients with CKD in a clinic-based setting. Study Design: Cohort study. Setting & Participants: This study included 379 new oral calcitriol users in the Veterans' Affairs Northwest Health Network. All had stages 3-4 CKD, hyperparathyroidism, and a serum PTH measurement before and 1-6 months after initiating oral calcitriol therapy. Predictors: Patient-level characteristics hypothesized to affect calcitriol response: race, body size, concurrent medications, and kidney function. Outcomes: Relative decrease in serum PTH concentration after starting oral calcitriol therapy. Measurements: Data were abstracted from the Veterans' Affairs Northwest Health Network (VISN 20) Data Warehouse, which includes electronic pharmacy and laboratory records. Results: Mean estimated glomerular filtration rate was 30 mL/min/1.73 m 2 and mean initial PTH concentration was 199 pg/mL. Regular- (0.25 μg/d) and low-dose (<0.25 μg/d) oral calcitriol were associated with on average 23% and 13% relative decreases in serum PTH concentrations, respectively. After adjustment for calcitriol dosage, initial PTH concentration, and time to follow-up measurement, African American race was associated with a blunted calcitriol response (geometric mean final PTH value, 26% higher; 95% CI, 8%-47%). Serum albumin concentration <3.5 g/dL also was associated with a diminished calcitriol response (geometric mean final PTH, 19% higher; 95% CI, 6%-35%). Although numbers were small, concurrent use of benzodiazepines and nonactivated vitamin D supplements was associated with a significantly greater PTH response. Limitations: Clinic-based study is limited by the availability of PTH measurements after starting calcitriol therapy. Study of a predominantly older male population. Conclusions: In patients with stages 3-4 CKD, African American race and low serum albumin level are associated with a diminished PTH response to oral calcitriol.
KW - Activated vitamin D
KW - calcitriol
KW - drug metabolism
KW - hyperparathyroidism
KW - parathyroid hormone
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U2 - 10.1053/j.ajkd.2011.11.041
DO - 10.1053/j.ajkd.2011.11.041
M3 - Article
C2 - 22285224
AN - SCOPUS:84859801372
SN - 0272-6386
VL - 59
SP - 645
EP - 652
JO - American Journal of Kidney Diseases
JF - American Journal of Kidney Diseases
IS - 5
ER -