| Vitamin D Dose, IU/d |  |  | |||
---|---|---|---|---|---|---|
Parameter, mean (SE) | Placebo | 1000 | 2000 | 4000 | 3 months Changeb | P-Value |
 n (at baseline) | 62 | 65 | 64 | 63 |  |  |
Total PTH, pg/mL |  |  |  |  | −2.98 [-4.41,-1.53] | <0.0001 |
 Baseline PTH, mean (SE) | 39.40 (14.20) | 41.15 (18.02) | 42.21 (20.94) | 42.96 (16.79) |  |  |
 3 months PTH, mean (SE) | 43.27 (18.21) | 39.83 (15.56) | 36.42 (15.69) | 34.18 (12.75) |  |  |
 Difference PTHc, mean (SE) | 3.93 (18.93) | −3.37 (17.84) | −6.76 (14.71) | −8.99 (12.36) |  |  |
25(OH)D, ng/mL | Â | Â | Â | Â | Â | Â |
 Baseline 25(OH)D, mean(SE) | 17.07 (1.03) | 17.33 (1.00) | 16.12 (0.98) | 17.79 (0.98) | 7.57 [6.69,8.46] | <0.0001 |
 3 months 25(OH)D, mean (SE) | 14.23 (0.96) | 28.12 (1.11) | 35.48 (1.21) | 47.30 (1.22) |  |  |
 Difference 25(OH)Dd, mean (SE) | −2.58 (0.66) | 11.01 (1.22) | 19.21 (1.21) | 29.79 (1.29) |  |  |
Calcium, mg/dL | Â | Â | Â | Â | Â | Â |
 1 month Calcium, mean (SE) | 9.54 (0.08) | 9.77 (0.13) | 9.77 (0.13) | 9.81 (0.12) |  |  |
 3 months Calcium, mean (SE) | 9.57 (0.09) | 9.59 (0.10) | 9.59 (0.10) | 9.77 (0.07) |  |  |