Three-year follow-up of serum 25-hydroxyvitamin D, parathyroid hormone, and bone mineral density in nursing home residents who had received 12 months of daily bread fortification with 125 μg of vitamin D 3

Table 2 Biochemical values and BMD changes before vitamin D bread consumption, at baseline of follow-up study (after 12 mo of vitamin D bread consumption) and after 12 and 36 months the supplementation with vitamin D was discontinued

Parameter	Vitamin D bread consumption (-12 mo)	Baseline of follow-up study (0 month)	12 month follow-up	36-month follow-up	P-value¹	P-value²	P-value³
Serum calcium (Normal: 2.15-2.55 mmol/L)	2.30 ± 0.14	2.31 ± 0.13	2.26 ± 0.13	2.29 ± 0.15	0.18	0.49	0.07
Serum 25(OH)D (Sufficiency: 50-125 nmol/l)	29.8 ± 9.3	127.3 ± 37.8	64.9 ± 24.8	28.0 ± 15.0	<0.001	<0.001	<0.001
Serum PTH (Normal: 16-62 pg/ml)	60.2 ± 42.6	18.8 ± 15.6	46.7 ± 21.2	48.4 ± 18.4	<0.001	<0.001	<0.001
Lumbar spine BMD (g/cm2)	0.825 ± 0.113	0.858 ± 0.134	0.855 ± 0.146	0.867 ± 0.142	0.81	0.32	0.65
Total hip BMD (g/cm2)	0.736 ± 0.128	0.927 ± 0.130	0.913 ± 0.130	0.907 ± 0.121	0.02	0.02	0.14

N = 23, Data expressed in mean ± SD.
¹Student’s t test for paired data (baseline vs. 12 month follow-up).
²Student’s t test for paired data (baseline vs. 36 month follow-up).
³Repeated-measures ANOVA. The interaction effect between sex and age was not statistically significant for any variable. There was a statistically significant main effect for age on 25(OH)D (F = 4.69, p = 0.007, partial eta squared = 0.92) and for gender on total hip BMD (F = 7.08, p = 0.05, partial eta squared = 0.59).

ISSN: 1475-2891