The Relationship of BMD Increases Between the First 12 Months and the Latter 12 Months by Daily Teriparatide Treatment

The degree of correlation between the first 12 months and the latter 12 months of increased bone mineral density (BMD) with teriparatide treatment is unknown. We retrospectively investigated the correlation between the first 12 months and the latter 12 months of increased BMD owing to teriparatide treatment. We retrospectively analyzed 357 patients (mean age, 78 years) with osteoporosis treated with teriparatide 20 μg/day for 24 months. The primary efficacy measure was the correlation between lumbar spine (LS) and femoral neck (FN) BMD increases from baseline to 12 months and from 12 to 24 months. The correlation between the first 12 months and the latter 12 months of increased BMD was evaluated. We investigated the correlation between the increases in BMD and the baseline procollagen type I N-terminal propeptide (PINP) concentration. LS BMD significantly increased by 9.7 ± 8.3 % in the first 12 months and 3.5 ± 4.8 % in the latter 12 months. FN BMD increased by 2.2 ± 8.4 % in the first 12 months and 1.3 ± 4.9 % in the latter 12 months. Increased LS and FN BMD were not significantly correlated between the first 12 months and the latter 12 months. The serum baseline PINP concentration was correlated with the LS BMD in the first 12 months, and similarly, the PINP concentration at 12 months was correlated with the latter 12 months of increased LS BMD. Increased BMD by teriparatide treatment in the first 12 months and the latter 12 months was not significantly correlated.