Table 2.

Multivariable Cox regression of the effect of cinacalcet on the occurrence of first clinical fracture, by intention-to-treat analysis

VariableaRelative Hazard (95% CI)P Value
Treatment (cinacalcet/placebo)0.84 (0.69 to 1.01)0.07
Age (yr)b1.38 (1.22 to 1.55)<0.001
Sex (ref=women)0.78 (0.64 to 0.96)0.02
Race (ref=white)
 Black0.48 (0.35 to 0.66)<0.001
 Other0.75 (0.57 to 1.00)0.05
Geographical region (ref=United States)
 Russia0.49 (0.30 to 0.82)0.01
 Latin America1.03 (0.72 to 1.47)0.87
 Europe0.76 (0.57 to 1.02)0.06
 Canada0.97 (0.62 to 1.50)0.89
 Australia0.59 (0.34 to 1.04)0.07
Tobacco use (ref=never)
 Current1.54 (1.18 to 1.99)0.001
 Former0.91 (0.72 to 1.15)0.43
Dialysis vintage (yr)1.05 (0.95 to 1.15)0.35
Type of vascular access (ref=natural fistula)
 Permanent catheter1.46 (1.09 to 1.94)0.01
 Graft1.51 (1.15 to 1.96)0.003
 Other1.35 (0.74 to 2.49)0.33
Alcohol use1.39 (1.10 to 1.76)0.01
Calcium-containing phosphate binder use1.16 (0.95 to 1.42)0.14
Hormone replacement therapy1.26 (0.94 to 1.70)0.13
Proton pump inhibitor use1.19 (0.97 to 1.47)0.09
History of cardiovascular diseasec0.95 (0.61 to 1.48)0.83
History of peripheral vascular disease0.84 (0.64 to 1.11)0.23
Other cardiac disease history (valvular heart disease and angina)1.27 (1.02 to 1.58)0.03
Amputation history0.87 (0.56 to 1.36)0.54
History of diabetes1.46 (1.15 to 1.83)0.002
History of bone fracture1.67 (1.36 to 2.06)<0.001
History of stroke1.67 (1.29 to 2.17)<0.001
Hemoglobin0.99 (0.89 to 1.09)0.78
Serum phosphorus (mg/dl)1.07 (0.96 to 1.18)0.23
Serum calcium (corrected) (mg/dl)1.11 (1.01 to 1.23)0.03
Serum BALP (ng/ml)1.09 (1.00 to 1.20)0.05
Serum 25-hydroxy cholecalciferol (µg/L)1.00 (0.90 to 1.12)0.99
Plasma intact PTH (pg/ml)d
 Log transformed0.04 (0.00 to 0.76)0.03
 Squared log transformed1.28 (1.02 to 1.60)0.04
  • ref, reference value.

  • a Both treatment and BALP have time-dependent effect; the effects shown in the table are time-averaged effects. Unless otherwise specified, all continuous variables were standardized; one unit is equivalent to 1 SD.

  • b Age by treatment interaction was not statistically significant (P=0.06).

  • c History of cardiovascular disease includes history of coronary artery disease, cardiac arrhythmia, coronary artery bypass graft, hypertension, heart failure, and myocardial infarction.

  • d The hazard ratios of the linear and squared PTH terms should be interpreted together and indicate that PTH had a nonlinear association with fractures; fracture rate is increased at the lower and higher ends of baseline PTH in this group of patients with secondary hyperparathyroidism.