Background Short-term changes in biochemical markers of bone turnover have been suggested as predictors of long-term response in bone mass density (BMD) during teriparatide treatment. However, few data are available, particularly regarding increases in hip BMD.
Objectives The aim of this study was to examine whether early changes in biochemical markers of bone turnover predict long-term changes of BMD in patients treated with teriparatide.
Methods BMD values at baseline and 18 months were obtained with a LUNAR Expert 1320 R. β-C-telopeptide of collagen 1 crosslinks (β-CTX1), osteocalcin (OC), alkaline phosphatase and 25 (OH) vitamin D3 were measured at baseline, 3 and at 18 months. The association between baseline and 3 months markers levels and BMD changes at the end of treatment was evaluated using Spearman correlation analysis (SPSS 21.0).
Results Sixty three patients were evaluated. 92,1% (58) were female and the mean age was 67,65±8,8 years. 60,3% (38) had glucocorticoid-induced osteoporosis and/or secondary to chronic inflammatory diseases. After treatment median DMD changes were: 0,088 g/cm2 in lumbar spine (gain of 10,65%), 0,024 g/cm2 in femoral neck (gain of 4,16%), 0,03g/cm2 in wards triangle (gain of 7,7%) and 0,011g/cm2 in total hip (gain of 1,1%).
At baseline, β-CTX1 and OC levels correlated positively with the variation of BMD in lumbar spine at 18 months (r =0,452; p=0,01 and r=0,305; p=0,04, respectively). Baseline OC levels also correlated significantly with BMD variation in femoral neck (r=0,524; p<0,01), wards triangle (r=0,442; p=0,02) and total hip (r=0,364; p=0,01).
Statistically significant correlation was found between β-CTX1 level at 3 months and BMD variation in femoral neck (r=0,389; p=0,01) and wards triangle (r=0,402; p=0,03). 3 months OC levels correlated significantly with femoral neck DMO variation (r=0,517; p<0,01) and wards triangle DMO variation (r=0,501; p<0,01).
No association was found between alkaline phosphatase and 25 (OH) vitamin D3 values at baseline and 3 months and BMD changes.
Conclusions In our study, we found an association between bone turnover markers levels at baseline and 3 months and final changes in BMD at the lumbar spine and total hip. The early measurement of bone turnover markers may be a useful tool to predict BMD response to this anabolic therapy.
Disclosure of Interest None declared