Association between P1NP and bone strength in postmenopausal women treated with teriparatide.

OBJECTIVE: To evaluate the association between P1NP and bone strength in postmenopausal women treated with teriparatide. MATERIALS AND METHODS: This prospective study enrolled 248 postmenopausal women with severe osteoporosis treated with teriparatide. Procollagen type 1 N-terminal propeptide (P1NP) were assessed at baseline, 3, 6, and 12 months. Lumbar spine (LS), femoral neck (FN), and total hip (TH) bone mineral density (BMD) and LS trabecular bone score (TBS) were measured by Dual-energy x-ray absorptiometry at baseline and 12 months. RESULTS: With teriparatide use, P1NP levels increase and peaked at 6 months. Significant increase in LS and hip BMD and LS TBS were also noted. The percentage change or absolute change >10 µg/L in PINP at 3 months was only related to changes in LS BMD at 12 months. With a median baseline P1NP level was 65.5 ng/mL, we found no correlation between P1NP and LS and hip BMD nor LS TBS. There was no association between LS TBS and axial BMD. After treatment, there was also no significance between the changes in TBS and axial BMD. Over the study period, 83.9% of the 248 participants were persistent with teriparatide at 3 months, 77.8% at 6 months, and 67.3% women at 12 months. CONCLUSION: P1NP levels may provide a signal of osteoporosis risk but is not related to bone strength. Early changes in P1NP may offer information regarding subsequent BMD response so standardized monitoring of P1NP levels at baseline and at 3 months should be considered during osteoporosis therapy. As an additional benefit, serum level monitoring during treatment may also improve medication persistence.

Utilizing nomograms to predict prevalent vertebral fracture risk: An analysis of dysmobility syndrome in a community-dwelling population.

BACKGROUND: To determine a reliable method to predict prevalent vertebral fractures (VF) by assessing the association between dysmobility syndrome (DS) and VF in a community-dwelling population. METHODS: This cross-sectional study enrolled 518 participants from fracture-prevention educational activities held in multiple communities in Taiwan. Assessments included questionnaires, fracture risk assessment tool (FRAX), bone mineral density (BMD) and body composition using dual-energy x-ray absorptiometry (DXA), lateral thoracolumbar spine x-rays (specifically T8-S1), grip strength (GS), walking speed, and fall history. RESULTS: DS was noted in 257 participants (49.6%) and VF was identified in 196 participants (37.8%). A higher prevalence of VF was noted in those with DS. The prevalence of VF was significantly associated with age, gender, FRAX both with and without BMD, osteoporosis, low GS, and DS. In multivariate models accounting for age and sex, the c-index was greater in those with low GS plus osteoporosis as compared to DS alone. Low GS, osteoporosis, and pre-BMD FRAX all had similar c-indexes. Pre-BMD FRAX plus low GS and osteoporosis was superior in predicting VF compared to pre-BMD FRAX plus low GS or osteoporosis alone. Besides the inclusion of age and gender, the nomogram with pre-BMD FRAX major osteoporosis fracture probability (MOF) plus low GS had improved correlation between the estimated and actual VF probability than those with pre-BMD FRAX MOF plus osteoporosis. CONCLUSIONS: The constructed nomogram containing pre-BMD FRAX MOF plus low GS may be considered as a first-line prevalent VF screening method. Those with high-risk scores should subsequently undergo vertebral radiography and/or BMD.

Integrating Muscle Health in Predicting the Risk of Asymptomatic Vertebral Fracture in Older Adults.

BACKGROUND: The utility of muscle health for predicting asymptomatic vertebral fracture (VF) is uncertain. We aimed to determine the effects of muscle health on bone quantity and quality in the older adults and to integrate these factors into a predictive model for VF. METHODS: We prospectively recruited participants with a body mass index <37 kg/m2. The total lean mass (TLM), appendicular skeletal muscle index, presence of sarcopenia, and bone mineral density were determined by dual-energy X-ray absorptiometry, and bone quality by the trabecular bone score (TBS). VF was diagnosed based on spine radiography. RESULTS: A total of 414 females and 186 males were included; 257 participants had VF. Lower TLM was significantly associated with poorer bone quantity and quality in both males and females. A low TBS (OR: 11.302, p = 0.028) and sarcopenia (Odds ratio (OR): 2.820, p = 0.002) were significant predictors of VF in males, but not bone quantity. Moreover, integrating TBS and sarcopenia into the predictive model improved its performance. CONCLUSIONS: Although TLM was associated with bone quantity and quality in both sexes, sarcopenia and a low TBS were significant predictors of asymptomatic VF only in male participants.

Vertebral Fractures in Type 2 Diabetes Patients: Utility of Trabecular Bone Score and Relationship With Serum Bone Turnover Biomarkers.

BACKGROUND: Patients with type 2 diabetes (T2D) have an increased risk for vertebral fracture (VF). The aim of this study is to determine the utility of trabecular bone score (TBS) in T2D patients with VF and the relationship of TBS with serum bone turnover biomarkers (SBTBs). METHODOLOGY: Postmenopausal T2D female patients were prospectively enrolled. All patients received: (1) dual-energy X-ray absorptiometry exam for bone mineral density (BMD), T-score, and TBS values; (2) lateral lumbar spine radiographs for VF assessment; and (3) SBTBs: bone specific alkaline phosphatase and Beta-C-Terminal telopeptides. BMD, T-score, TBS, and SBTBs were tested for association with VF. RESULTS: The study included 285 T2D patients (mean age = 61.1 years) and 32 patients had VF (11.2%). TBS had the strongest association with VF in T2D patients (area under curve 0.775). The TBS cutoff values for VF are 1.279 in T-score ≥1 and 1.236 in T-score <-1. In patients without VF, all sites of BMD and TBS are significantly associated with SBTBs, but in patients with VF, no associations are found between SBTBs and all sites of BMD and TBS. CONCLUSIONS: TBS can assess bone quality in the spine. The low TBS cutoff values for T2D patients with VF imply T2D does impair bone quality. Thus, TBS should be incorporated in VF risk assessment in T2D patients. In addition, a dissociated relationship between BMD and TBS with SBTBs represents imbalanced bone turnover rate and results in bone fragility and VF.

Effect of Chemotherapy on Dual-Energy X-ray Absorptiometry (DXA) Body Composition Precision Error in Head and Neck Cancer Patients.

BACKGROUND: Precision error in dual-energy X-ray absorptiometry (DXA) is defined as difference in results due to instrumental and technical factors given no biologic change. The aim of this study is to compare precision error in DXA body composition scans in head and neck cancer patients before and 2 months after chemotherapy. METHODOLOGY: A total of 34 male head and neck cancer patients with normal body mass index (BMI) were prospectively enrolled and all patients received 2 consecutive DXA scans both before and after 2 months of chemotherapy for a total of 4 scans. The precision error of 3 DXA body composition values (lean mass, fat mass, and bone mineral content) was calculated for total body and 5 body regions (arms, legs, trunk, android, and gynoid). Precision errors before and after treatment were compared using generalized estimating equation model. RESULTS: There was no significant change in precision error for the DXA total body composition values following chemotherapy; lean mass (0.33%-0.40%, p = 0.179), total fat mass (1.39%-1.70%, p = 0.259) and total bone mineral content (0.42%-0.56%, p = 0.243). However, there were significant changes in regional precision error; trunk lean mass (1.19%-1.77%, p = 0.014) and android fat mass (2.17%-3.72%, p = 0.046). CONCLUSIONS: For head and neck cancer patients, precision error of DXA total body composition values did not change significantly following chemotherapy; however, there were significant changes in fat mass in the android and lean mass in the trunk. Caution should be exercised when interpreting longitudinal DXA body composition data in those body parts.

Risk factor for first-incident hip fracture in Taiwanese postmenopausal women.

OBJECTIVE: The variation in hip fracture risk between countries is greater than 10-fold. The present study aimed at identifying risk factors that resulted in the first occurrence of hip fracture in Taiwanese postmenopausal women. MATERIALS AND METHODS: A case-control study with a patient group of 50 postmenopausal women, who were admitted to Keelung Chang Gung Hospital, Keelung, Taiwan due to the first incident of accidental hip fracture, was used to examine potential risk factors, including bone mass. Fifty women without hip fracture, selected from those undergoing general health evaluation at the Gynecology Outpatient Clinic at Keelung Chang Gung Hospital, were used as the control group and were matched to the case patients according to age. Evaluation consisted of a questionnaire, interview to document risk factors, physical examination (to record body height and body weight), and examination [dual-energy X-ray absorptiometry used to measure bone mineral density (BMD) of the hip and spine]. RESULTS: The average age of participants of both groups was 79.6 years. Lower level of education, younger age at menopause, increased body height, weight-bearing exercise less than three times per week, and lower BMD were associated with first-incident hip fracture. Total hip BMD was a stronger predictor than the BMD of different sites. Participants in the control group had a significantly higher prevalence of chronic diseases and a history of cataracts or glaucoma compared with those in the patient group. CONCLUSION: While total hip BMD is the strongest predictor of hip fracture, increasing awareness of osteoporosis prevention by educating people about good lifestyle habits and how to maintain BMD is prioritized for preventing the first-incident hip fracture in Taiwanese women.