Bone density and strength from thoracic and lumbar CT scans both predict incident vertebral fractures independently of fracture location

In a population-based study, we found that computed tomography (CT)-based bone density and strength measures from the thoracic spine predicted new vertebral fracture as well as measures from the lumbar spine, suggesting that CT scans at either the thorax or abdominal regions are useful to assess vertebral fracture risk.

INTRODUCTION

Prior studies have shown that computed tomography (CT)-based lumbar bone density and strength measurements predict incident vertebral fracture. This study investigated whether CT-based bone density and strength measurements from the thoracic spine predict incident vertebral fracture and compared the performance of thoracic and lumbar bone measurements to predict incident vertebral fracture.

METHODS

This case-control study of community-based men and women (age 74.6 ± 6.6) included 135 cases with incident vertebral fracture at any level and 266 age- and sex-matched controls. We used baseline CT scans to measure integral and trabecular volumetric bone mineral density (vBMD) and vertebral strength (via finite element analysis, FEA) at the T8 and L2 levels. Association between these measurements and vertebral fracture was determined by using conditional logistic regression. Sensitivity and specificity for predicting incident vertebral fracture were determined for lumbar spine and thoracic bone measurements.

RESULTS

Bone measurements from T8 and L2 predicted incident vertebral fracture equally well, regardless of fracture location. Specifically, for predicting vertebral fracture at any level, the odds ratio (per 1-SD decrease) for the vBMD and strength measurements at L2 and T8 ranged from 2.0 to 2.7 (p < 0.0001) and 1.8 to 2.8 (p < 0.0001), respectively. Results were similar when predicting fracture only in the thoracic versus the thoracolumbar spine. Lumbar and thoracic spine bone measurements had similar sensitivity and specificity for predicting incident vertebral fracture.

CONCLUSION

These findings indicated that like those from the lumbar spine, CT-based bone density and strength measurements from the thoracic spine may be useful for identifying individuals at high risk for vertebral fracture.

Prediction of incident vertebral fracture using CT-based finite element analysis

Prior studies show vertebral strength from computed tomography-based finite element analysis may be associated with vertebral fracture risk. We found vertebral strength had a strong association with new vertebral fractures, suggesting that vertebral strength measures identify those at risk for vertebral fracture and may be a useful clinical tool.

INTRODUCTION

We aimed to determine the association between vertebral strength by quantitative computed tomography (CT)-based finite element analysis (FEA) and incident vertebral fracture (VF). In addition, we examined sensitivity and specificity of previously proposed diagnostic thresholds for fragile bone strength and low BMD in predicting VF.

METHODS

In a case-control study, 26 incident VF cases (13 men, 13 women) and 62 age- and sex-matched controls aged 50 to 85 years were selected from the Framingham multi-detector computed tomography cohort. Vertebral compressive strength, integral vBMD, trabecular vBMD, CT-based BMC, and CT-based aBMD were measured from CT scans of the lumbar spine.

RESULTS

Lower vertebral strength at baseline was associated with an increased risk of new or worsening VF after adjusting for age, BMI, and prevalent VF status (odds ratio (OR) = 5.2 per 1 SD decrease, 95% CI 1.3-19.8). Area under receiver operating characteristic (ROC) curve comparisons revealed that vertebral strength better predicted incident VF than CT-based aBMD (AUC = 0.804 vs. 0.715, p = 0.05) but was not better than integral vBMD (AUC = 0.815) or CT-based BMC (AUC = 0.794). Additionally, proposed fragile bone strength thresholds trended toward better sensitivity for identifying VF than that of aBMD-classified osteoporosis (0.46 vs. 0.23, p = 0.09).

CONCLUSION

This study shows an association between vertebral strength measures and incident vertebral fracture in men and women. Though limited by a small sample size, our findings also suggest that bone strength estimates by CT-based FEA provide equivalent or better ability to predict incident vertebral fracture compared to CT-based aBMD. Our study confirms that CT-based estimates of vertebral strength from FEA are useful for identifying patients who are at high risk for vertebral fracture.

Changes in bone mineral density (BMD): a longitudinal study of osteoporosis patients in the real-world setting

In clinical practice, the frequency of patients achieving improved T-scores and the expected change in bone mineral density (BMD) according to osteoporosis drugs is unknown. We found that osteoporosis medications infrequently achieve improved femoral neck T-scores over 1.2 years. BMD increases were more often seen with IV bisphosphonates and denosumab.

PURPOSE

To determine the frequency of osteoporosis patients achieving improvement in T-scores and quantify the change in bone mineral density (BMD) over time according to osteoporosis medication use.

METHODS

The study included all patients receiving clinical care at United Osteoporosis Centers, Gainesville, GA, 1995-2015, who had at least two measures of femoral neck BMD (N = 1232). We evaluated successive pairs of BMD tests to describe the distribution of transitions between T-score categories. Generalized estimating equations were used to estimate %BMD change between successive pairs of BMD tests according to osteoporosis medication, adjusted for age, sex, height, weight, baseline BMD, previous fracture, and follow-up time.

RESULTS

Mean (±SD) age was 68 (±10) years, and 90% of patients were women. Mean baseline T-score was - 2.04 (± 0.85). In total, 1232 patients had 4918 pairs of successive BMD tests, with a mean 1.2 years (± 0.9) between assessments. Frequency of transition to an improved T-score category was 41% when prior T-score ≤ - 3.5, and 15% when prior T-score - 1.99 to - 1.50. Most individuals (69%) remained in the same T-score category. BMD increased 0.54% (95% CI 0.23-0.85%) with IV bisphosphonates and 1.23% (95% CI 0.56-1.90%) with denosumab, whereas no significant change was seen with oral bisphosphonates, teriparatide, or raloxifene.

CONCLUSIONS

Osteoporosis patients are unlikely to improve femoral neck T-scores over 1.2 years. Additional studies are needed to determine the optimal time to repeat BMD testing while receiving osteoporosis treatment and to determine whether fracture risk is reduced in patients who achieve target T-scores.

Population-based study of age- and sex-related differences in muscle density and size in thoracic and lumbar spine: the Framingham study

Relative age-related deficit in trunk muscle density was greater in women than men whereas the relative decrease in muscle mass with age was similar in both sexes. The greater muscle fat content and greater age-related fat accumulation among women may contribute to women suffering more functional disabilities than men.

INTRODUCTION

A better understanding of the effect of aging on trunk musculature will have implications for physical function, disability, pain, and risk of injury in older adults. Thus, we determined the age- and sex-related differences in muscle density and size of both thoracic and lumbar trunk muscles.

METHODS

In this cross-sectional study, muscle density and size were measured from quantitative computed tomography (QCT) scans for 10 trunk muscle groups at different vertebral levels in 250 community-based men and women aged 40 to 90 years from the Framingham Offspring and Third Generation cohorts.

RESULTS

Trunk muscles in men were 20-67% larger and had 5-68% higher density than in women. The relative age-related deficits in muscle size were similar in both sexes, and decreased on average by ~ 8% per decade in both sexes. In contrast, women had greater age-related decreases in muscle density than men (- 17% in women, and - 11% in men, p < 0.01). Age-related declines varied by specific muscle, tending to be greater for outer trunk muscles than for paraspinal muscles, but within a given muscle the age-related changes in muscle density and size were similar among spinal levels.

CONCLUSION

This comprehensive study of trunk muscle deficits with increasing age may have important implications for physical function, disability, pain, and risk of injury in older adults. The greater levels of mobility impairments with aging in women may in part be explained by greater proportion of intramuscular fat tissue and greater age-related fat accumulation in trunk muscles in women than in men.

Severity of aortic calcification is positively associated with vertebral fracture in older men--a densitometry study in the STRAMBO cohort

In older men, severe abdominal aortic calcification and vertebral fracture (both assessed using dual-energy X-ray absorptiometry) were positively associated after adjustment for confounders including bone mineral density.

INTRODUCTION

Abdominal aortic calcification (AAC) is associated with higher fracture risk, independently of low bone mineral density (BMD). Dual-energy X-ray absorptiometry (DXA) can be used to assess both vertebral fracture and AAC and requires less time, cost, and radiation exposure.

METHODS

We conducted a cross-sectional study of the association between AAC and prevalent vertebral fractures in 901 men≥50 years old. We used DXA (vertebral fracture assessment) to evaluate BMD, vertebral fracture, and AAC.

RESULTS

Prevalence of vertebral fracture was 11%. Median AAC score was 1 and 12% of men had AAC score>6. After adjustment for age, weight, femoral neck BMD, smoking, ischemic heart disease, diabetes, and hypertension, AAC score>6 (vs ≤6) was associated with 2.5 (95% CI, 1.4-4.5) higher odds of vertebral fracture. Odds of vertebral fracture for AAC score>6 increased with vertebral fracture severity (grade 1, OR=1.8; grade 2, OR=2.4; grade 3, OR=4.4; trend p<0.01) and with the number of vertebral fractures (1 fracture, OR=2.0, >1 fracture, OR=3.5). Prevalence of vertebral fracture was twice as high in men having both a T-score<-2.0 and an AAC score>6 compared with men having only one of these characteristics.

CONCLUSIONS

Men with greater severity AAC had greater severity and greater number of vertebral fractures, independently of BMD and co-morbidities. DXA can be used to assess vertebral fracture and AAC. It can provide a rapid, safe, and less expensive alternative to radiography. DXA may be an important clinical tool to identify men at high risk of adverse outcomes from osteoporosis and cardiovascular disease.

Identification of prevalent vertebral fractures using CT lateral scout views: a comparison of semi-automated quantitative vertebral morphometry and radiologist semi-quantitative grading

We compared vertebral fracture assessment by semi-automated quantitative vertebral morphometry measurements with the conventional semi-quantitative (SQ) grading using lateral CT scout views. The semi-automated morphometry method showed good to excellent agreement with the visual SQ grading by radiologists for identification of vertebral fractures.

INTRODUCTION

Semi-automated quantitative vertebral morphometry (QM) measurements may enhance management of osteoporosis patients by providing an efficient means to identify vertebral fractures (VFx). We compared identification of prevalent VFx by semi-automated QM to SQ grading.

METHODS

A non-radiologist performed semi-automated QM from CT lateral scout views in 200 subjects (102 men, 98 women, 65.8 ± 8.9 years) selected from the Framingham Heart Study Multidetector CT Study. VFx were classified in the QM approach based on using Genant's criteria for deformities, and compared with conventional SQ grading performed by experienced radiologists as the gold standard. The kappa (k) statistics, percent agreement (% Agree), sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV) were computed.

RESULTS

Among 200 subjects, 57 had mild and 41 had moderate or severe VFx by visual SQ grading. Per-person analyses showed excellent agreement between the two methods, with k = 0.780. The % Agree ranged from 86.7% to 91.2%, the SE was 81.3%-96%, and the SP was 86.5%-92%. Among 2,588 vertebrae analyzed, 107 had mild and 49 had moderate or severe VFx by visual SQ grading. Per-vertebra analyses revealed good agreement, with k = 0.580. Agreement between the methods tended to be highest in L1-L4 region. Agreement and validity measures were higher when only moderate and severe fractures were included.

CONCLUSION

The semi-automated quantitative vertebral morphometry measurements from CT lateral scout views provided good to excellent agreement with the standard SQ grading for assessment of prevalent vertebral fractures.

Intra-and inter-reader reliability of semi-automated quantitative morphometry measurements and vertebral fracture assessment using lateral scout views from computed tomography

Intra-and inter-reader reliability of semi-automated quantitative vertebral morphometry measurements was determined using lateral computed tomography (CT) scout views. The method requires less time than conventional morphometry. Reliability was excellent for vertebral height measurements, good for height ratios, and comparable to semi-quantitative grading by radiologists for identification of vertebral fractures.

INTRODUCTION

Underdiagnosis and undertreatment of vertebral fracture (VFx) is a well-known problem worldwide. Thus, new methods are needed to facilitate identification of VFx. This study aimed to determine intra- and inter-reader reliability of semi-automated quantitative vertebral morphometry based on shape-based statistical modeling (SpineAnalyzer, Optasia Medical, Cheadle, UK).

METHODS

Two non-radiologists independently assessed vertebral morphometry from CT lateral scout views at two time points in 96 subjects (50 men, 46 women, 70.3 ± 8.9 years) selected from the Framingham Heart Study Offspring and Third Generation Multi-Detector CT Study. VFxs were classified based solely on morphometry measurements using Genant's criteria. Intraclass correlation coefficients (ICCs), root mean squared coefficient of variation (RMS CV) and kappa (k) statistics were used to assess reliability.

RESULTS

We analyzed 1,246 vertebrae in 96 subjects. The analysis time averaged 5.4 ± 1.7 min per subject (range, 3.2-9.1 min). Intra-and inter-reader ICCs for vertebral heights were excellent (>0.95) for all vertebral levels combined. Intra-and inter-reader RMS CV for height measurements ranged from 2.5% to 3.9% and 3.3% to 4.4%, respectively. Reliability of vertebral height ratios was good to fair. Based on morphometry measurements alone, readers A and B identified 51-52 and 46-59 subjects with at least one prevalent VFx, respectively, and there was a good intra-and inter-reader agreement (k = 0.59-0.69) for VFx identification.

CONCLUSIONS

Semi-automated quantitative vertebral morphometry measurements from CT lateral scout views are convenient and reproducible, and may facilitate assessment of VFx.

Reliability of vertebral fracture assessment using multidetector CT lateral scout views: the Framingham Osteoporosis Study

Two radiologists evaluated images of the spine from computed tomography (CT) scans on two occasions to diagnose vertebral fracture in 100 individuals. Agreement was fair to good for mild fractures, and agreement was good to excellent for more severe fractures. CT scout views are useful to assess vertebral fracture.

INTRODUCTION

We investigated inter-reader agreement between two radiologists and intra-reader agreement between duplicate readings for each radiologist, in assessment of vertebral fracture using a semi-quantitative method from lateral scout views obtained by CT.

METHODS

Participants included 50 women and 50 men (age 50-87 years, mean 70 years) in the Framingham Study. T4-L4 vertebrae were assessed independently by two radiologists on two occasions using a semi-quantitative scale as normal, mild, moderate, or severe fracture.

RESULTS

Vertebra-specific prevalence of grade ≥ 1 (mild) fracture ranged from 3% to 5%. We found fair (κ = 56-59%) inter-reader agreement for grade ≥ 1 vertebral fractures and good (κ = 68-72%) inter-reader agreement for grade ≥ 2 fractures. Intra-reader agreement for grade ≥ 1 vertebral fracture was fair (κ = 55%) for one reader and excellent for another reader (κ = 77%), whereas intra-reader agreement for grade ≥ 2 vertebral fracture was excellent for both readers (κ = 76% and 98%). Thoracic vertebrae were more difficult to evaluate than the lumbar region, and agreement was lowest (inter-reader κ = 43%) for fracture at the upper (T4-T9) thoracic levels and highest (inter-reader κ = 76-78%) for the lumbar spine (L1-L4).

CONCLUSIONS

Based on a semi-quantitative method to classify vertebral fractures using CT scout views, agreement within and between readers was fair to good, with the greatest source of variation occurring for fractures of mild severity and for the upper thoracic region. Agreement was good to excellent for fractures of at least moderate severity. Lateral CT scout views can be useful in clinical research settings to assess vertebral fracture.

Application of the National Osteoporosis Foundation Guidelines to postmenopausal women and men: the Framingham Osteoporosis Study

We applied the 2008 National Osteoporosis Foundation (NOF) Guidelines to Framingham Osteoporosis Study participants and found nearly one half of Caucasian postmenopausal women and one sixth of men aged 50 years and older would be recommended for osteoporosis treatment. Given the high proportion of persons recommended for treatment, NOF Guidelines may need to be re-evaluated with respect to budget impact.

INTRODUCTION

Little is known about the public health impact of the NOF Guidelines. Therefore, we determined the proportion of US Caucasians recommended for treatment of osteoporosis according to NOF Guidelines (2003 and 2008).

METHODS

One thousand nine hundred and forty-six postmenopausal women and 1,681 men aged > or =50 years from the Framingham Study with information on bone mineral density (1987-2001) were included. Information on clinical predictors was used to estimate the 10-year probability of hip and major osteoporotic fracture by FRAX (version 3.0).

RESULTS

Overall proportion of women meeting treatment criterion was less when the 2008 NOF Guidelines were applied (41.1%) compared with 2003 Guidelines (47.8%). The proportion of women aged <65 years meeting treatment criterion was much less when applying 2008 Guidelines (23.1% in 2003, 8.3% in 2008), whereas the proportion of women aged >75 years increased slightly (78.3% in 2003, 86.0% in 2008). Seventeen percent of men aged > or =50 years met treatment criterion (2.5% aged 50-64 years, 49.8% aged >75 years).

CONCLUSIONS

Nearly one half of Caucasian postmenopausal women and one sixth of men aged 50 years and older would be recommended for osteoporosis treatment according to 2008 NOF Guidelines. Given the high proportion of persons recommended for treatment, NOF Guidelines may need to be re-evaluated with respect to budget impact.

Racial differences in cervical cancer mortality in Chicago

Racial differences in cervical cancer mortality in Chicago were examined. Age-adjusted mortality in Blacks (10.0/100,000) was over twice the rate found in Whites (4.6/100,000). Age-specific rates also showed significant excess mortality among Blacks. After stratification by a group-level defined poverty indicator, the race differential in age-adjusted rates remained significant. The race differential in age-specific rates diminished in the group with more than 30% living below the national poverty level, in contrast to the group with 30% or fewer living below the national poverty level, in whom race differences were more marked. Methodological issues concerning hysterectomy prevalence, Hispanic ethnicity, and social class must be considered with respect to interpretation of these findings.