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Summary: We examined how spinal location affects the relationships between quantitative computed tomography (QCT)-based bone measurements and prevalent vertebral fractures. Upper spine (T4-T10) fractures appear to be more strongly related to bone measures than lower spine (T11-L4) fractures, while lower spine measurements are at least as strongly related to fractures as upper spine measurements. Introduction: Vertebral fracture (VF), a common injury in older adults, is most prevalent in the mid-thoracic (T7-T8) and thoracolumbar (T12-L1) areas of the spine. However, measurements of bone mineral density (BMD) are typically made in the lumbar spine. It is not clear how the associations between bone measurements and VFs are affected by the spinal locations of both bone measurements and VF. Methods: A community-based case-control study includes 40 cases with moderate or severe prevalent VF and 80 age- and sex-matched controls. Measures of vertebral BMD, strength (estimated by finite element analysis), and factor of risk (load:strength ratio) were determined based on QCT scans at the L3 and T10 vertebrae. Associations were determined between bone measures and prevalent VF occurring at any location, in the upper spine (T4-T10), or in the lower spine (T11-L4). Results: Prevalent VF at any location was significantly associated with bone measures, with odds ratios (ORs) generally higher for measurements made at L3 (ORs = 1.9-3.9) than at T10 (ORs = 1.5-2.4). Upper spine fracture was associated with these measures at both T10 and L3 (ORs = 1.9-8.2), while lower spine fracture was less strongly associated (ORs = 1.0-2.4) and only reached significance for volumetric BMD measures at L3. Conclusions: Closer proximity between the locations of bone measures and prevalent VF does not strengthen associations between bone measures and fracture. Furthermore, VF etiology may vary by region, with VFs in the upper spine more strongly related to skeletal fragility. [ABSTRACT FROM AUTHOR]

Summary: 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. [ABSTRACT FROM AUTHOR]

Summary: 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. [ABSTRACT FROM AUTHOR]

Abstract: Nitric oxide (NO), produced by endothelial cells, is a signaling molecule synthesized from l-arginine by nitric oxide synthases (NOS). NO is known to reduce the ratio of receptor activator of nuclear factor KappaB (RANKL)/osteoprotegerin (OPG), leading to decreased osteoclastogenesis and a reduction in bone resorption. Endothelial nitric oxide synthase (eNOS or NOS3) is the predominant constitutive isoform of nitric NOS within bone. Recently, a NOS3 polymorphism, Glu298Asp, previously implicated in osteoporosis, failed to demonstrate an association with bone mineral density (BMD), although there was some indication of an association with selected geometry indices. Since a single polymorphism does not capture all of the potential variants in a given gene, we investigated a broader coverage of the NOS3 gene with bone density/ultrasound and geometry indices in a sample of unrelated individuals from the Framingham Offspring Study. Our results indicated that the Glu298Asp polymorphism was not associated with BMD but suggested some haplotype-based associations in the linkage disequilibrium (LD) region that included the Glu298Asp polymorphism with several geometry indices. Although our findings exhibited several associations with selected bone density/ultrasound and geometry indices, the nominally significant associations are regarded as primarily hypothesis generating and suggest that replication in other samples is needed. Thus, NOS3 genetic variation does not appear to be a major contributor to adult bone density/ultrasound and geometry in our sample. [Copyright &y& Elsevier]

Abstract: Introduction : Femoral geometry contributes to bone strength and predicts hip fracture risk. The purpose of this study was to evaluate heritability (h 2) of geometric indices of the proximal hip and to perform whole-genome linkage analyses of these traits, adjusted for body size. Methods : DXA scans of the proximal femur from 1473 members of 323 pedigrees (age range 31–96 years) from the population-based Framingham Osteoporosis Study were obtained. Using the hip structural analysis program, we measured femoral neck length (FNL, cm) and neck-shaft angle (NSA); subperiosteal width (WID, cm), cross-sectional area (CSA, cm2); and section modulus (Z, cm3) at the narrowest section of the neck (NN), intertrochanteric (IT) and femoral shaft (S) regions. Linkage analyses were performed for the above indices with a set of 636 markers using variance components maximum likelihood method. Results : Substantial genetic influences were found for all geometric phenotypes, with h 2 values between 0.28 (NSA) and 0.70 (IT_WID). Adjustment for height and BMI did not alter h 2 of NSA and FNL but decreased h 2 of the cross-sectional indices. We obtained substantial linkage (multipoint LOD >3.0) for S_Z at 2p21 and 21q11 and S_WID at Xq25–q26. Inclusion of height and BMI as covariates resulted in much lower LOD scores for S_Z, whereas linkage signals for S_Z at 4q25, S_CSA at 4q32 and S_CSA and S_Z at 15q21 increased after the adjustment. Linkage of FNL at 1q and 13q, NSA at 2q and NN_WID at 16q did not change after the adjustment. Conclusion : Suggestive linkages of bone geometric indices were found at 1q, 2p, 4q, 13q, 15q and Xq. The identification of significant linkage regions after adjustment for BMI and height may point to QTLs influencing femoral bone geometry independent of body size. [Copyright &y& Elsevier]

Insulin resistance and oxidative stress are associated with accelerated telomere attrition in leukocytes. Both are also implicated in the biology of aging and in aging-related disorders, including hypertension. We explored the relations of leukocyte telomere length, expressed by terminal restriction fragment (TRF) length, with insulin resistance, oxidative stress and hypertension. We measured leukocyte TRF length in 327 Caucasian men with a mean age of 62.2 years (range 40–89 years) from the Offspring cohort of the Framingham Heart Study. TRF length was inversely correlated with age ( r = –0.41, P < 0.0001) and age-adjusted TRF length was inversely correlated with the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) ( r =–0.16, P = 0.007) and urinary 8-epi-PGF2α ( r = –0.16, P = 0.005) – an index of systemic oxidative stress. Compared with their normotensive peers, hypertensive subjects exhibited shorter age-adjusted TRF length (hypertensives = 5.93 ± 0.042 kb, normotensives = 6.07 ± 0.040 kb, P = 0.025). Collectively, these observations suggest that hypertension, increased insulin resistance and oxidative stress are associated with shorter leukocyte telomere length and that shorter leukocyte telomere length in hypertensives is largely due to insulin resistance. [ABSTRACT FROM AUTHOR]

The choice of a phenotype is critical for the study of a complex genetically regulated process, such as aging. To date, most of the twin and family studies have focused on broad survival measures, primarily age at death or exceptional longevity. However, on the basis of recent studies of twins and families, biological age has also been shown to have a strong genetic component, with heritability estimates ranging from 27% to 57%. The aim of this review is twofold: first, to summarize growing consensus on reliable methods of biological age assessment, and second, to demonstrate validity of this phenotype for research in the genetics of aging in humans. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Studies investigating hand osteoarthritis (OA) as a single entity have not shown strong linkage of the disease with any chromosomal sites. We undertook this study to test our hypothesis that phenotypes of hand OA may show stronger linkage than has been shown for overall hand OA. METHODS: We performed a factor analysis on measures of hand OA to determine patterns of disease. Using the joint regions identified by this analysis, we performed a genome-wide linkage analysis for OA susceptibility loci using 426 original cohort members and 790 offspring cohort members in 267 pedigrees. Radiographic OA features evaluated included the Kellgren/Lawrence score, osteophytes, and joint space narrowing. Prior to linkage analysis, standardized residuals were computed from regression analysis of each phenotype on age. This was performed separately for each sex and cohort. The variance component model (GeneHunter) was then applied to the normalized scores of the residuals of both sexes and cohorts. RESULTS: There was evidence suggestive of linkage (logarithm of odds [LOD] score >1.5) at 16 sites. Four of these sites had LOD scores >3.0. Two of these sites (identified in the full sample) included a linkage region for OA of the distal interphalangeal (DIP) joint on chromosome 7 (155 cM; LOD score 3.06) and a linkage region for OA of the first carpometacarpal (CMC) joint on chromosome 15 (81 cM; LOD score 6.25). The other 2 sites (identified in women) included a linkage region for OA of the DIP joint on chromosome 1 (202 cM; LOD score 3.03) and a linkage region for OA of the first CMC joint on chromosome 20 (4 cM; LOD score 3.74). CONCLUSION: These data suggest that several chromosomes contain hand OA susceptibility genes and that a joint-specific approach may be more rewarding than a global approach to the genetics of hand OA. Further investigation of these regions is warranted using finer maps and other populations. [ABSTRACT FROM AUTHOR]

Fc γRIIB are low-affinity immunoglobulin (Ig)G receptors that we previously demonstrated to negatively regulate IgE-induced mast cell activation when coaggregated with Fc ℇRI. Here, we engineered and characterized a bispecific reagent capable of coaggregating Fc γRIIB with Fc ℇRI on human mast cells and basophils. A bispecific antibody was constructed by chemically crosslinking one Fab’ fragment against human IgE and one Fab’ fragment against human Fc γRII. This molecule was used to coaggregate Fc ℇRI with Fc γRII on human mast cells and basophils sensitized with human IgE antibodies, and the effect of coaggregation was examined on mediator release upon challenge with specific antigen. When used under these conditions, this bispecific antibody not only failed to trigger the release of histamine by IgE-sensitized cells, but it also prevented specific antigen from triggering histamine release. Comparable inhibitions were observed with mast cells and basophils derived in vitro from cord blood cells and with peripheral blood basophils. The bispecific antibody described here is the prototype of similar molecules that could be used in new therapeutic approaches of allergic diseases based on the coaggregation of activating receptors, such as Fc ℇRI, with inhibitory receptors, such as Fc γRIIB, that are constitutively expressed by mast cells and basophils. [ABSTRACT FROM AUTHOR]

Summary: 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. [ABSTRACT FROM AUTHOR]

Context: Estrogen and related hormone therapies activate estrogen receptors, which in turn regulate genes for several cardiovascular disease (CVD) risk factors. Relatively little is known, however, about the impact of genetic variation in estrogen receptor alpha (ESR1) on CVD risk.Objective: To investigate whether the ESR1 c.454-397T>C polymorphism is associated with CVD risk.Design, Setting, and Participants: Prospective study of 1739 unrelated men and women from the population-based offspring cohort of the Framingham Heart Study, who were followed up from 1971 to 1998.Main Outcome Measures: Total atherosclerotic CVD events, defined as recognized or unrecognized myocardial infarction (MI), angina pectoris, coronary insufficiency, intermittent claudication, coronary heart disease death, or atherothrombotic stroke (n = 178); major atherosclerotic CVD, defined as recognized acute MI, coronary insufficiency, coronary heart disease death, or atherothrombotic stroke (n = 83); and recognized acute MI (n = 59).Results: Twenty percent of participants (n = 352) were homozygous for the ESR1 c.454-397C allele. After adjustment for covariates (age, sex, body mass index, hypertension, diabetes mellitus, total cholesterol, high-density lipoprotein cholesterol, and cigarette smoking), the CC genotype was significantly associated with major atherosclerotic CVD, with an odds ratio of 2.0 (95% confidence interval [CI], 1.3-3.2; P =.004) compared with individuals with the CT or TT genotypes. Participants with the CC genotype had 3.0-fold greater odds of MI (95% CI, 1.7-5.2; P<.001) compared with those with the CT or TT genotype. The results remained significant when analyses were restricted to men; too few women had events to study them separately.Conclusions: Individuals with the common ESR1 c.454-397CC genotype have a substantial increase in risk of MI. Whether ESR1 c.454-397T>C is causally related to MI risk or in linkage disequilibrium with 1 or more causal variants remains to be determined. These findings support the importance of estrogen receptors in CVD susceptibility, especially in men. Estrogen receptor variation also has potential to explain recent conflicting data regarding the effects of hormone therapy on CVD susceptibility in women. [ABSTRACT FROM AUTHOR]

The article offers a study that aims to vertebral fracture risk. Topics discussed include the association between vertebral strength measures and incident vertebral fracture in men and women, mentions the bone strength estimates by computed tomography (CT), based finite element analysis (FEA) that provide equivalent ability to predict incident vertebral fracture, and information on the fragile bone strength for the proximal femur and lumbar spine.

Background: Older persons with type 2 diabetes are at higher risk for functional impairment than are their age-matched counterparts without-diabetes. We therefore sought to identify factors associated with impaired physical function in older persons with type 2 diabetes by using a cross-sectional study design.Methods: We studied 1238 persons with type 2 diabetes who were 55 years of age or older and enrolled in the Type II Diabetes Patient Outcomes Research Team (PORT) project. Subjects were primary care patients at a large staff model health maintenance organization who had completed a mailed survey that collected information about demographics (age, race, marital status, income, education, gender, and body mass index [BMI]), health behaviors (exercise, smoking, and alcohol), care and control of diabetes (therapy, self-reported glucose control, home glucose monitoring, and disease duration), mood (Center for Epidemiologic Studies--Depression Scale [CES-D]), comorbidity, and the Short-Form-36 health survey (SF-36). We evaluated the bivariate relationships between the PFI- 10, a 10-item measure of physical function from the SF-36, and candidate independent variables from the domains described previously. Variables that were significant at an a level of .10 were entered into a multiple linear regression model.Results: There were eight independent predictors of impaired physical function (all p < .05, R2 = .40). Factors associated with impaired function in order of their relative importance were as follows: a higher comorbidity score, older age, obesity, lack of regular exercise, CES-D score higher than 20, taking insulin, lower formal education, and abstinence from alcohol.Conclusions: Increased comorbidity and older age are associated with poorer function, as is the severity of diabetes and less formal education. Exercise, lower BMI, and better mood are associated with better function. Therefore, promoting regular exercise and weight loss, in addition to treating depression, are likely to preserve or even improve the functional status of older persons with type 2 diabetes. Moderate alcohol use may be beneficial as well. The extent to which these relationships persist in prospective studies or clinical trials remains to be evaluated. [ABSTRACT FROM AUTHOR]

Femoral geometry and body size are both characterized by substantial heritability. The purpose of this study was to discern whether hip geometry and body size (height and body mass index, BMI) share quantitative trait loci (QTL). Dual-energy X-ray absorptiometric scans of the proximal femur from 1,473 members in 323 pedigrees (ages 31-96 years) from the Framingham Osteoporosis Study were studied. We measured femoral neck length, neck-shaft angle, subperiosteal width (outer diameter), cross-sectional bone area, and section modulus, at the narrowest section of the femoral neck (NN), intertrochanteric (IT), and femoral shaft (S) regions. In variance component analyses, genetic correlations (rho ( G )) between hip geometry traits and height ranged 0.30-0.59 and between hip geometry and BMI ranged 0.11-0.47. In a genomewide linkage scan with 636 markers, we obtained nominally suggestive linkages (bivariate LOD scores > or =1.9) for geometric traits and either height or BMI at several chromosomes (4, 6, 9, 15, and 21). Two loci, on chr. 2 (80 cM, BMI/shaft section modulus) and chr. X (height/shaft outer diameter), yielded bivariate LOD scores > or =3.0; although these loci were linked in univariate analyses with a geometric trait, neither was linked with either height or BMI. In conclusion, substantial genetic correlations were found between the femoral geometric traits, height and BMI. Linkage signals from bivariate linkage analyses of bone geometric indices and body size were similar to those obtained in univariate linkage analyses of femoral geometric traits, suggesting that most of the detected QTL primarily influence geometry of the hip. [ABSTRACT FROM AUTHOR]

Data from 1668 men (316 cardiovascular disease events) from the Framingham Offspring Study was reanalysed, specifically examining APOE:smoking interactions. Overall hazard ratio (HR) for smoking was 1.95 (1.52, 2.50) compared to non-smokers. Using ℇ3/3 as a referent group, in non-smokers HRs for ℇ2 carriers (ℇ2+; 1.04 (0.61, 1.76) and ℇ4 carriers (ℇ4+; 1.04 (0.70, 1.54) showed no major risk increase. In smokers, HRs were 1.96 (1.26, 2.78) in ℇ3ℇ3 men, 3.46 (2.14, 5.60; p = 0.09 for interaction) in ℇ2+ and 3.81 (2.49, 5.84; p = 0.01 for interaction), with a significant interaction between daily cigarette consumption and APOE genotype on risk (p = 0.03). The potential mechanism for this APOEℇ 4:smoking interaction was examined in a second study of 728 Caucasian patients with diabetes, where markers of reactive oxygen species were available. APOE genotype was not associated with plasma OX-LDL or total antioxidant status (TAOS) in non-smokers. However, in smokers ℇ4+ had 26.7% higher plasma OX-LDL than other genotypes ( APOE:smoking interaction p = 0.04), while ℇ2+ had 28.4% higher plasma TAOS than ℇ3ℇ3 and ℇ4+ combined ( APOE:smoking interaction p = 0.026). Although direct extrapolation needs to be considered with caution, these results identify that the cardiovascular disease risk-raising effect of ℇ4+ is confined to smokers, and a feasible mechanism is presented by the reduced antioxidant capacity/increased OX-LDL of apoE4. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This article describes the development and randomized evaluation of a tailored nutrition education CD-ROM program for participants in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) in North Carolina. DESIGN: After randomization to intervention or control groups, participants completed a baseline survey and were resurveyed immediately after program use and 1 to 2 months postintervention. SETTING: Two WIC clinics in central North Carolina. PARTICIPANTS: A total of 307 respondents to the follow-up survey (response rate 74.8%) comprised the study sample. Participants were female (96%), 20% were pregnant, and 50% were minorities (African American and other). Intervention: The interactive CD-ROM consisted of a targeted video soap opera, dietary assessment, and individually tailored dietary feedback and strategies for change. MAIN OUTCOME MEASURES: Measures included total fat and fruit and vegetable intake, knowledge of low-fat and infant feeding choices, self-efficacy, and stages of change. ANALYSIS: Descriptive statistics assessed baseline comparability of study groups; analysis of covariance and F tests were used to assess program effects at follow-up. RESULTS: Intervention group members increased self-efficacy (P <.01) and scored significantly higher (P <.05) on both low-fat and infant feeding knowledge compared with controls. No differential effect was observed for dietary intake variables. CONCLUSIONS AND IMPLICATIONS: The findings suggest that one dose of an interactive CD-ROM program can impact mediators of dietary change but may be insufficient to change behavior. [ABSTRACT FROM AUTHOR]