Differences in the trajectory of bone mineral density change measured at the total hip and femoral neck between men and women following hip fracture

Sex differences and predictors of anti-osteoporosis medication use in the 12 months after hip fracture surgery in adults 65 or older

PURPOSE

This study evaluates sex differences and predictors of anti-osteoporosis medication (AOM) use following a hip fracture, with a focus on older men who exhibit higher mortality rates post-fracture compared to women over the age of 65.

METHODS

Participants included 151 men and 161 women aged 65 and older with hip fractures. The outcome, AOM use, was assessed at baseline (≤ 22 days of hospitalization) and at 2, 6, and 12 months post-hip fracture. Generalized estimating equations (GEE) modeled sex differences and predictors of AOM use during the year post-fracture in 255 participants with complete baseline data and ≥ 1 follow-up observation.

RESULTS

Of the 312 participants, only 53 used AOM at baseline, and 35 initiated use during follow-up. In the unadjusted GEE model, AOM use was significantly less likely in men (OR = 0.42; 95% CI, 0.22-0.78) compared to women. For both men and women, baseline use of AOM was a significant predictor (OR = 28.3; 95% CI, 5.4-148.0 vs. 41.6; 95% CI, 14.0-123.0). The other significant predictors by sex were osteoporosis diagnosis (OR = 3.19; 95% CI, 1.16-8.77) and minimal alcohol use (OR = 3.26; 95% CI, 1.34-7.94) for women versus age (OR = 1.09; 95% CI, 1.01-1.18) for men.

CONCLUSION

In older adults with hip fractures, AOM use is low over the year post-fracture and men are less likely to report AOM use compared to women which has implications for important sex differences in predictors of use. Further research is needed to address overall disparities and sex differences in AOM use.

Effects of Multicomponent Home-Based Intervention on Muscle Composition, Fitness, and Bone Density After Hip Fracture

BACKGROUND

Mechanistic factors on the pathway to improving independent ambulatory ability among hip fracture patients by a multicomponent home-based physical therapy intervention that emphasized aerobic, strength, balance, and functional training are unknown. The aim of this study was to determine the effects of 2 different home-based physical therapy programs on muscle area and attenuation (reflects muscle density) of the lower extremities, bone mineral density (BMD), and aerobic capacity.

METHODS

Randomized controlled trial of home-based 16 weeks of strength, endurance, balance, and function exercises (PUSH, n = 19) compared to seated active range-of-motion exercises and transcutaneous electrical neurostimulation (PULSE, n = 18) in community-dwelling adults >60 years of age within 26 weeks of hip fracture.

RESULTS

In PUSH and PULSE groups combined, the fractured leg had lower muscle area and muscle attenuation and higher subcutaneous fat than the nonfractured leg (p < .001) at baseline. At 16 weeks, mean muscle area of the fractured leg was higher in the PUSH than PULSE group (p = .04). Changes in muscle area were not significantly different when compared to the comparative PULSE group. There was a clinically relevant difference in change in femoral neck BMD between groups (p = .05) that showed an increase after PULSE and decrease after PUSH. There were generally no between-group differences in mean VO2peak tests at 16-week follow-up, except the PUSH group reached a higher max incline (p = .04).

CONCLUSIONS

The treatment effects of a multicomponent home-based physical therapy intervention on muscle composition, BMD, and aerobic capacity were not significantly different than an active control intervention in older adults recovering from hip fracture.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01783704.

East Asians' T-scores for the diagnosis of osteoporosis should be calculated using ethnicity- and gender-specific BMD reference ranges: justifications

The 2013 ISCD consensus recommended a Caucasian female reference database for T-score calculation in men, which says "A uniform Caucasian (non-race adjusted) female reference database should be used to calculate T-scores for men of all ethnic groups." However, this statement was recommended for the US population, and no position was taken with respect to BMD reference data or ethnicity matching outside of the USA. In East Asia, currently, a Japanese BMD reference database is universally adopted in Japan for clinical DXA diagnosis, while both local BMD and Caucasian BMD reference databases are in use in Mainland China, South Korea, Taiwan, and Singapore. In this article, we argue that an ethnicity- and gender-specific BMD database should be used for T-score calculations for East Asians, and we list the justifications why we advocate so. Use of a Caucasian BMD reference database leads to systematically lower T-scores for East Asians and an overestimation of the prevalence of osteoporosis. Using a female BMD reference database to calculate T-scores for male patients leads to higher T-score values and an underestimation of the prevalence of osteoporosis. Epidemiological evidence does not support using a female BMD reference database to calculate T-scores for men. We also note that BMD reference databases collected in Asia should be critically evaluated for their quality.

Site-Specific Differences in Bone Mineral Density of Proximal Femur Correlate with the Type of Hip Fracture

The aim of this study was to investigate whether site-specific differences in bone mineral density (BMD) of proximal femur correlate with the type of hip fracture using quantitative computed tomography. Femoral neck (FN) fractures were classified as nondisplaced or displaced subtypes. Intertrochanteric (IT) fractures were classified as A1, A2, or A3. The severe hip fractures were identified as displaced FN fractures or unstable IT fractures (A2 and A3). In total, 404 FN fractures (89 nondisplaced and 317 displaced) and 189 IT fractures (76 A1, 90 A2, and 23 A3) were enrolled. Areal BMD (aBMD) and volumetric BMD (vBMD) were measured in the regions of total hip (TH), trochanter (TR), FN, and IT of the contralateral unfractured femur. IT fractures exhibited lower BMD than FN fractures (all p ≤ 0.01). However, unstable IT fractures had higher BMD compared with stable ones (p < 0.01). After adjusting for covariates, higher BMD in TH and IT were associated with IT A2 (A1 vs. A2: odds ratios (ORs) from 1.47 to 1.69, all p < 0.01). Low bone measurements were risk factors for stable IT fractures (IT A1 vs. FN fracture subtypes: ORs from 0.40 to 0.65, all p < 0.01). There are substantial site-specific differences in BMD between IT fractures A1 and displaced FN fractures. Higher bone density was associated with unstable IT fracture when compared with stable ones. The understanding of biomechanics of various fracture types could help to improve the clinical management of these patients.

Own the Fall: AOA Critical Issues

Falls are the most common cause of injury to older patients, resulting in >3 million emergency room visits per year and 290,000 hip fractures annually in the United States. Orthopaedic surgeons care for the majority of these patients; however, they are rarely involved in the assessment of fall risk and providing prevention strategies. Falls also occur perioperatively (e.g., in patients with arthritis and those undergoing arthroplasty). Preoperatively, up to 40% of patients awaiting joint arthroplasty sustain a fall, and 20% to 40% have a fall postoperatively. Risk factors for falls include intrinsic factors such as age and comorbidities that are not modifiable as well as extrinsic factors, including medication reconciliation, improvement in the environment, and the management of modifiable comorbidities that can be optimized. Simple in-office fall assessment tools are available that can be adapted for the orthopaedic practice and be used to identify patients who would benefit from rehabilitation. Orthopaedic surgeons should incorporate these strategies to improve care and to reduce fall risk and associated adverse events.

Sex Differences in Recovery Across Multiple Domains Among Older Adults With Hip Fracture

BACKGROUND

Hip fractures are a public health problem among older adults, but most research on recovery after hip fracture has been limited to females. With growing numbers of hip fractures among males, it is important to determine how recovery outcomes may differ between the sexes.

METHODS

168 males and 171 females were enrolled within 15 days of hospitalization with follow-up visits at 2, 6, and 12 months postadmission to assess changes in disability, physical performance, cognition, depressive symptoms, body composition, and strength, and all-cause mortality. Generalized estimating equations examined whether males and females followed identical outcome recovery assessed by the change in each outcome.

RESULTS

The mean age at fracture was similar for males (80.4) and females (81.4), and males had more comorbidities (2.5 vs 1.6) than females. Males were significantly more likely to die over 12 months (hazard ratio 2.89, 95% confidence interval: 1.56-5.34). Changes in outcomes were significantly different between males and females for disability, gait speed, and depressive symptoms (p < .05). Both sexes improved from baseline to 6 months for these measures, but only males continued to improve between 6 and 12 months. There were baseline differences for most body composition measures and strength; however, there were no significant differences in change by sex.

CONCLUSIONS

Findings confirm that males have higher mortality but suggest that male survivors have continued functional recovery over the 12 months compared to females. Research is needed to determine the underlying causes of these sex differences for developing future prognostic information and rehabilitative interventions.

Change in vertebral strength and bone mineral density in men and women over the year post-hip fracture: a subgroup analysis

This study examines changes in bone density and strength in the spine over the year after hip fracture to see if there are differences in the changes between men and women. Results show losses in the spine that may increase the risk of subsequent vertebral fractures, particularly for women.

PURPOSE

Compare changes over the first year post-hip fracture in vertebral bone mineral density (BMD) and compressive strength, measured from quantitative computed tomography (QCT) scans of the spine (T12-L1), between women and men.

METHODS

QCT scans were performed on 37 participants (21 men and 16 women) at 2 and 12 months post-hip fracture as part of an ancillary observational study of hip fracture recovery in older community-dwelling men and women. Vertebral BMD and compressive strength were calculated using VirtuOst® (O.N. Diagnostics, Berkeley, CA). Unpaired t-tests were used to compare men and women with respect to baseline demographics, measurements of BMD and bone strength for the whole vertebra and the cortical and trabecular compartments, and any changes in these parameters between months 2 and 12.

RESULTS

At 2 months post-fracture, there were no significant sex differences in any measurements of vertebral strength or BMD. Between months 2 and 12, vertebral strength decreased significantly in women (- 3.8%, p < 0.05) but not in men (- 2.3%, p < 0.20), vertebral trabecular BMD decreased similarly in both sexes (- 5.7% women; - 6.0% men), but cortical BMD did not change for either sex.

CONCLUSION

Despite the small sample size, these findings suggest that appreciable loss of vertebral trabecular bone can occur for both sexes in the year following hip fracture, which may increase the risk of subsequent vertebral fracture, particularly for women.

Physical function and lean body mass as predictors of bone loss after hip fracture: a prospective follow-up study

Background

Predictors of bone deterioration after hip fracture have not been well characterized. The aim of this study was to examine the associations of physical function and lean body mass (LBM) with loss of bone density and strength in older people recovering from a hip fracture.

Methods

A total of 81 over 60-year-old, community-dwelling men and women operated for a hip fracture participated in this 1-year prospective follow-up study. Distal tibia total volumetric bone mineral density (vBMD_TOT, mg/cm³) and compressive strength index (BSI, g²/cm⁴) and mid-tibia cortical vBMD (vBMD_CO, mg/cm³) and bending strength index (SSI, mm³) were assessed in both legs by peripheral quantitative computed tomography (pQCT) at baseline (on average 10 weeks after fracture) and at 12 months. At baseline, LBM was measured with a bioimpedance device and physical function with the Short Physical Performance Battery (SPPB) and perceived difficulty in walking outdoors. Robust multivariable linear regression models were used to estimate the associations of physical function and LBM with the change in bone parameters at 12-months.

Results

The mean change in distal tibia vBMD_TOT and BSI in both legs ranged from − 0.9 to − 2.5%. The change in mid-tibia vBMD_CO and SSI ranged from − 0.5 to − 2.1%. A lower SPPB score, difficulty in walking outdoors and lower LBM predicted greater decline in distal tibia vBMD_TOT in both legs. A lower SPPB score and difficulty in walking outdoors were also associated with a greater decline in distal tibia BSI in both legs. At the midshaft site, a lower SPPB score and lower LBM were associated with greater decline in SSI on the fractured side.

Conclusions

Older hip fracture patients with low physical function and lower LBM may be at risk for greater decline in tibia bone properties during the first post-fracture year. Acknowledgement of the risk factors could assist in developing interventions and care to promote bone health and overall recovery.

Trial registration

ISRCTN, ISRCTN53680197. The trial was registered retrospectively but before the recruitment was completed. Registered March 3, 2010.

Comparing Longitudinal Sarcopenia Trends by Definitions Across Men and Women After Hip Fracture

OBJECTIVES

While sarcopenia is prevalent after hip fracture in the acute postfracture period, little is known about the prevalence after discharge. This study assessed longitudinal trends in sarcopenia prevalence over 12 months after hip fracture using three different operational definitions.

DESIGN

Prospective observational study.

SETTING

Baltimore Hip Studies seventh cohort.

PARTICIPANTS

A total of 82 men and 78 women, aged 65 years and older, with surgical repair of a nonpathological hip fracture.

MEASUREMENTS

Baseline assessment included a dual-energy X-ray absorptiometry scan and interview. Follow-up assessments, which additionally included performance measures, occurred 2, 6, and 12 months after admission. Using these measures, three sarcopenia definitions were assessed over the year following hip fracture: European Working Group on Sarcopenia in Older Persons (EWGSOP), International Working Group on Sarcopenia (IWGS), and Foundation for the National Institutes of Health (FNIH).

RESULTS

EWGSOP and IWGS provided the highest prevalence of sarcopenia (62%-69% in men, 42%-62% in women), while prevalence by FNIH was much lower for men (15%-19%) and women (5%-12%). For both men and women, the agreement between EWGSOP and IWGS definitions was excellent, and FNIH showed poor agreement with them, supported by various statistical measures across first-year follow-up. Prevalence was stable over time in men by all definitions, while the prevalence in women by FNIH was lowest at 2 months, significantly increased at 6 months (P = .03), and remained higher at 12 months. Whether sarcopenia prevalence differed significantly by sex varied by time point and definition; however, when different, men had a higher prevalence than women (P < .05). While some participants recovered from sarcopenia over time, some also became newly sarcopenic.

CONCLUSION

The prevalence of sarcopenia after fracture differed greatly for EWGSOP and IWGS compared to FNIH. Overall, there appeared to be no reduction in sarcopenia over the year after hip fracture, regardless of definition. Future research should examine the relationship between sarcopenia prevalence and functional recovery. J Am Geriatr Soc 68:1537-1544, 2020.

Differences in geometric strength at the contralateral hip between men with hip fracture and non-fractured comparators

Older men sustain excess bone mineral density (BMD) declines after hip fracture; however, BMD provides no information on mechanical structure and strength. The aim was to assess whether changes in hip bone geometry in older men after hip fracture differ than that expected with aging. Two cohorts were used: Baltimore Hip Studies 7th cohort (BHS-7) and Baltimore Men's Osteoporosis Study (MOST). The sample (N = 170) included older Caucasian men with hip fracture that were propensity score matched (1:1) to community-dwelling non-fractured comparators. Hip Structural Analysis (HSA) calculated aerial BMD and metrics of bone structural strength: cross-sectional bone area (CSA), cortical outer diameter (OD), section modulus (SM), and centroid position (CP). Mixed-effect models estimated changes in HSA parameters and adjusted robust regression models evaluated between-cohort differences in annual percent change at the narrow neck (NN), intertrochanteric (IT), and femoral shaft (FS). Hip fracture was associated with statistically greater declines in NN CSA (β = -2.818; 95% CI: -3.300%, -2.336%), SM (β = -1.896%; 95% CI: -2.711%, -1.080%) and CP (β = -0.884%; 95% CI: -0.889%, -0.880%) and significantly larger increases in NN OD (β = 0.187%; 95% CI: 0.185%, 0.190%). Differences in IT HSA parameters were like the NN but larger in magnitude, while there were favorable changes in FS geometry where fragility fractures are rare. Findings indicate there are declines in bone structure and strength at the NN and IT regions of the proximal femur in older men during hip fracture recovery that far exceed what occurs during normal aging.

Effects of a Home-Based Physical Rehabilitation Program on Tibial Bone Structure, Density, and Strength After Hip Fracture: A Secondary Analysis of a Randomized Controlled Trial

Weight‐bearing physical activity may decrease or prevent bone deterioration after hip fracture. This study investigated the effects of a home‐based physical rehabilitation program on tibial bone traits in older hip fracture patients. A population‐based clinical sample of men and women operated for hip fracture (mean age 80 years, 78% women) was randomly assigned into an intervention (n = 40) and a standard care control group (n = 41) on average 10 weeks postfracture. The intervention group participated in a 12‐month home‐based rehabilitation intervention, including evaluation and modification of environmental hazards, guidance for safe walking, nonpharmacological pain management, motivational physical activity counseling, and a progressive, weight‐bearing home exercise program comprising strengthening exercises for the lower legs, balance training, functional exercises, and stretching. All participants received standard care. Distal tibia (5% proximal to the distal end plate) compressive bone strength index (BSI; g²/cm⁴), total volumetric BMD (vBMD_TOT; mg/cm³), and total area (CSA_TOT; mm²), as well as midtibia (55%) strength–strain index (SSI; mm³), cortical vBMD (vBMD_CO; mg/cm³), and ratio of cortical to total area (CSA_CO/CSA_TOT) were assessed in both legs by pQCT at baseline and at 3, 6, and 12 months. The intervention had no effect (group × time) on either the distal or midtibial bone traits. At the distal site, BSI of both legs, vBMD_TOT of the fractured side, and CSA_TOT of the nonfractured side decreased significantly over time in both groups 0.7% to 3.1% (12 months, p < 0.05). At the midshaft site, CSA_CO/CSA_TOT and SSI of both legs, and vBMD_CO of the fractured leg, decreased significantly over time in both groups 1.1% to 1.9% (12 months, p < 0.05). Trabecular and cortical bone traits of the tibia on the fractured and the nonfractured side deteriorated throughout follow‐up. The home‐based physical rehabilitation intervention aimed at promoting mobility recovery was unable to prevent bone deterioration in older people after hip fracture. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

The spatial differences in bone mineral density and hip structure between low-energy femoral neck and trochanteric fractures in elderly Chinese using quantitative computed tomography

The purpose of this study was to investigate the differences in bone mineral density (BMD) and hip structure between femoral neck and trochanteric fractures in elderly Chinese individuals using quantitative computed tomography (QCT). A total of 625 Chinese patients (mean age 75.8 years) who sustained low-energy hip fractures (female: 293 femoral neck, 175 trochanteric; male: 82 femoral neck, 75 trochanteric) were recruited. Each patient underwent a hip QCT scan. The areal BMD (aBMD) of the contralateral normal hip was obtained using a computed tomography X-ray absorptiometry module. Using the bone investigation toolkit (BIT) module, the femoral neck was divided into four quadrants: supero-anterior (SA), infero-anterior (IA), infero-posterior (IP), and supero-posterior (SP). Estimated cortical thickness, cortical BMD, and trabecular BMD were measured in each quadrant. Using the hip structure analysis (HSA) function, several parameters were calculated. Stratified by sex, covariance analyses were applied to compare the femoral neck fractures group with trochanteric fractures group after adjustments for age, height, and weight. In women, trochanteric fractures exhibited lower trabecular BMD and estimated cortical thickness at three quadrants of the femoral neck (IA: P = 0.02, P < 0.01; IP: P < 0.01, P = 0.01; SP: P = 0.01, P < 0.01), and lower aBMD at the trochanter area (P < 0.01); femoral neck fractures exhibited lower cortical BMD and estimated cortical thickness at the SA quadrant (P = 0.04, P = 0.01). Differences in HSA parameters were not statistically significant. Among all parameters, the most valuable ones to discrimination of hip fracture type are estimated cortical thickness of the SA quadrant of femoral neck and the aBMD of the trochanter area. In men, only lower cortical BMD at the SP quadrant and aBMD at the trochanter were found in the trochanteric fractures (P = 0.02, P < 0.01). QCT outcomes indicate that spatial differences are helpful to explore the pathogenesis of different type of hip fractures. In women, trochanteric fractures are related to severer osteoporosis, whereas cortical fragility in the SA region of the femoral neck predominates in cases of femoral neck fractures. In men, trochanteric fractures are related to more bone loss of trochanter.

Incident fracture is associated with a period of accelerated loss of hip BMD: the Study of Osteoporotic Fractures

Bone loss following a fracture could increase the risk of future fractures. In this study, we found that elderly women who had an upper body fracture or multiple fractures lost more bone at the hip than those who did not fracture. This suggests a possible systemic bone loss response initiated by fracture.

INTRODUCTION

A prior fracture is one of the strongest predictors of subsequent fracture risk, but the etiology of this phenomenon remains unclear. Systemic bone loss post-fracture could contribute to increased risk of subsequent fractures. Therefore, in this study, we investigated whether incident fractures, including those distant to the hip, are associated with accelerated loss of hip bone mineral density (BMD) in elderly women.

METHODS

We analyzed data from 3956 Caucasian women aged ≥ 65 years who were enrolled in the Study of Osteoporotic Fractures and completed hip BMD measurements at study visit 4 (year 6) and visit 6 (year 10). Clinical fractures between visits 4 and 6 were ascertained from triannual questionnaires and centrally adjudicated by review of community radiographic reports. Subjects provided questionnaire information and clinical variables at examinations for known and potential covariates. Generalized linear models were used to calculate average annual percent change in total hip BMD between visits 4 and 6 for each incident fracture type and for upper body and lower body fractures combined. A subset of women (n = 3783) was analyzed for annual total hip BMD change between study visits 4 and 5 and between study visits 5 and 6 to evaluate change in total hip BMD during these 2-year intervals.

RESULTS

Women with incident upper body fracture or incident lower body fracture exhibited reductions in total hip BMD of 0.89 and 0.77% per year, respectively, while women who did not fracture exhibited reductions in total hip BMD of 0.66% per year during the 4-year period. Accelerated loss of hip BMD was isolated to the 2-year time interval that included the fracture. Loss of total hip BMD was not affected by the number of days from fracture to follow up DXA.

CONCLUSIONS

Systemic bone loss following fracture may increase the risk of future fractures at all skeletal sites. There is a need for improved understanding of mechanisms leading to apparent accelerated bone loss following a fracture in order to reduce subsequent fracture risk.

Soluble Tumor Necrosis Factor Alpha Receptor 1, Bone Resorption, and Bone Mineral Density in the Year Following Hip Fractures: The Baltimore Hip Studies

Although inflammation is known to influence bone turnover and bone mineral density (BMD), less is known about role of soluble tumor necrosis factor alpha receptor 1 (sTNFα-R1) in changes in bone turnover and BMD in the year after hip fracture. We studied 245 persons (117 men and 128 women) from the Baltimore Hip Studies. Bone turnover markers of resorption (carboxy-terminal type I collagen cross-links [CTX-I]) and formation (amino-terminal propeptide type I collagen [P1NP]), BMD of the contralateral hip, and sTNFα-R1 were measured within 15 days of hospitalization and 2, 6, and 12 months later. Latent class growth modeling was used to determine sTNFα-R1 trajectories. Weighted generalized estimating equations were used to examine the association of sTNFα-R1 trajectories with serum levels of CTX-I and P1NP and BMD; standardized beta coefficients (βˆ) are reported. Higher baseline sTNFα-R1 was significantly associated with a greater rate of CTX-I change (βˆ = 0.26, p = 0.004). Four distinct sTNFα-R1 trajectories were identified. The two groups with higher sTNFα-R1 levels during the year following fracture had faster increasing levels of CTX-I compared to the group with lowest sTNFα-R1 levels (men: group 3: βˆ = 0.76, p = 0.02; group 4: βˆ = 1.4, p < 0.001; women: group 3; βˆ = 0.67, p = 0.02; group 4: βˆ = 1.3, p = 0.004). Men in the highest sTNFα-R1 group had a greater decline in BMD compared to the lowest sTNFα-R1 group (2-month βˆ = -0.01, p = 0.01; 6-month: βˆ = -0.09, p = 0.001; 12-months: βˆ = -0.1, p < 0.001). An increasing rate of CTX-I was associated with a steeper decline in total hip BMD in those within higher sTNFα-R1 trajectory groups (p < 0.001). CTX-I was significantly increased with sTNFα-R1 in both sexes. CTX-I and the highest sTNFα-R1 trajectory were significantly associated with declines in total hip BMD in men. Interventions that reduce systemic inflammation should be explored to reduce bone resorption and prevent a decline in BMD after hip fracture. © 2018 American Society for Bone and Mineral Research.

Human osteoblasts exhibit sexual dimorphism in their response to estrogen on microstructured titanium surfaces

BACKGROUND

Osseointegration is dependent on the implant surface, surrounding bone quality, and the systemic host environment, which can differ in male and female patients. Titanium (Ti) implants with microstructured surfaces exhibit greater pullout strength when compared to smooth-surfaced implants and exhibit enhanced osteogenic cellular responses in vitro. Previous studies showed that 1α,25-dihydroxyvitamin D3 [1α,25(OH)₂D₃] has a greater effect on rat osteoblast differentiation on microstructured Ti compared to smooth Ti surfaces and tissue culture polystyrene (TCPS). The stimulatory effect of 17β-estradiol (E₂) on differentiation is observed in female osteoblasts on micro-rough Ti, but it is not known if male osteoblasts behave similarly in response to E₂ and microtopography. This study assessed whether human male and female osteoblasts exhibit sex-specific differences in response to E₂ and 1α,25(OH)₂D₃ when cultured on microstructured Ti surfaces.

METHODS

Osteoblasts from three male and three female human donors were cultured on Ti discs with varying surface profiles: a smooth pretreatment (PT), a coarse grit-blasted/acid-etched (SLA), and an SLA surface having undergone modification in a nitrogen environment and stored in saline to maintain hydrophilicity (modSLA). Cells cultured on these surfaces were treated with E₂ or 1α,25(OH)₂D₃.

RESULTS

Male and female human osteoblasts responded similarly to microstructure although there were donor-specific differences; cell number decreased, and osteocalcin (OCN), osteoprotegerin (OPG), and latent and active transforming growth factor 1 increased on SLA and modSLA compared to TCPS. Female osteoblasts had higher alkaline phosphatase activity and OCN production than male counterparts but produced less OPG. Both sexes responded similarly to 1α,25(OH)₂D₃. E₂ treatment reduced cell number and increased osteoblast differentiation and factor production only in female cells.

CONCLUSIONS

Male and female human osteoblasts respond similarly to microstructure and 1α,25(OH)₂D₃ but exhibit sexual dimorphism in substrate-dependent responses to E₂. E₂ affected female osteoblasts, suggesting that signaling is sex-specific and surface-dependent. Donor osteoblasts varied in response, demonstrating the need to test multiple donors when examining human samples. Understanding how male and female cells respond to orthopedic biomaterials will enable greater predictability post-implantation as well as therapies that are more patient-specific.

Persistence of depressive symptoms and gait speed recovery in older adults after hip fracture

OBJECTIVE

Depression after hip fracture in older adults is associated with worse physical performance; however, depressive symptoms are dynamic, fluctuating during the recovery period. The study aim was to determine how the persistence of depressive symptoms over time cumulatively affects the recovery of physical performance.

METHODS

Marginal structural models estimated the cumulative effect of persistence of depressive symptoms on gait speed during hip fracture recovery among older adults (n = 284) enrolled in the Baltimore Hip Studies 7th cohort. Depressive symptoms at baseline and at 2-month and 6-month postadmission for hip fracture were evaluated by using the Center for Epidemiological Studies Depression Scale, and persistence of symptoms was assessed as a time-averaged severity lagged to standardized 3 m gait speed at 2, 6, and 12 months.

RESULTS

A 1-unit increase in time-averaged Center for Epidemiological Studies Depression score was associated with a mean difference in gait speed of -0.0076 standard deviations (95% confidence interval [CI]: -0.0184, 0.0032; P = .166). The association was largest in magnitude from baseline to 6 months: -0.0144 standard deviations (95% CI: -0.0303, 0.0015; P = 0.076). Associations for the other time intervals were smaller: -0.0028 standard deviations (95% CI: -0.0138, 0.0083; P = .621) at 2 months and -0.0121 standard deviations (95% CI: -0.0324, 0.0082; P = .238) at 12 months.

CONCLUSION

Although not statistically significant, the magnitude of the numerical estimates suggests that expressing more depressive symptoms during the first 6 months after hip fracture has a meaningful impact on functional recovery.

Prediction of changes in bone mineral density in the elderly: contribution of "osteogenomic profile"

The contribution of genetic variants to longitudinal bone loss has not been well documented. We constructed an "osteogenomic profile" based on 62 BMD-associated genetic variants and showed that the profile was significantly associated with bone loss, independently from baseline BMD and age. The osteogenomic profile can help predict bone loss in an individual.

INTRODUCTION

The rate of longitudinal bone loss (ΔBMD) is a risk factor for fracture. The variation in ΔBMD is partly determined by genetic factors. This study sought to define the association between an osteogenomic profile and ΔBMD.

METHODS

The osteogenomic profile was created from 62 BMD-associated SNPs from genome-wide association studies (GWAS) that were genotyped in 1384 elderly men and women aged 60+ years. Weighted genetic risk scores (GRS) were constructed for each individual by summing the products of the number of risk alleles and the sex-specific regression coefficients [associated with BMD from GWAS]. ΔBMD, expressed as annual percent change-in-BMD, was determined by linear regression analysis for each individual who had had at least two femoral neck BMD measurements.

RESULTS

The mean ΔBMD was - 0.65% (SD 1.64%) for women and - 0.57% (SD 1.40%) for men, and this difference was not statistically significant (P = 0.32). In women, each unit increase in GRS was associated with 0.21% (SE 0.10) higher ΔBMD at the femoral neck (P = 0.036), and this association was independent of baseline BMD and age. In logistic regression analysis, each unit increase of GRS was associated with 41% odds (95%CI: 1.07-1.87) of rapid bone loss (ΔBMD ≤ - 1.2%/year; mean of rapid loss group = - 2.2%/year). There was no statistically significant association between ΔBMD and GRS in men.

CONCLUSIONS

We conclude that the osteogenomic profile constructed from BMD-associated genetic variants is modestly associated with long-term changes in femoral neck BMD in women, but not in men.

Older men who sustain a hip fracture experience greater declines in bone mineral density at the contralateral hip than non-fractured comparators

Men experience declining bone mineral density (BMD) after hip fracture; however, changes attributable to fracture are unknown. This study evaluated the excess BMD decline attributable to hip fracture among older men. Older men with hip fracture experienced accelerated BMD declines and are at an increased risk of secondary fractures.

INTRODUCTION

The objective was to determine whether bone mineral density (BMD) changes in men after hip fracture exceed that expected with aging.

METHODS

Two cohorts were used: Baltimore Hip Studies 7th cohort (BHS-7) and Baltimore Men's Osteoporosis Study (MOST). BHS-7 recruited older adults (N = 339) hospitalized for hip fracture; assessments occurred within 22 days of admission and at 2, 6, and 12 months follow-up. MOST enrolled age-eligible men (N = 694) from population-based listings; data were collected at a baseline visit and a second visit that occurred between 10 and 31 months later. The combined sample (n = 452) consisted of Caucasian men from BHS-7 (n = 89) and MOST (n = 363) with ≥ 2 dual-energy X-ray absorptiometry scans and overlapping ranges of age, height, and weight. Mixed-effect models estimated rates of BMD change, and generalized linear models evaluated differences in annual bone loss at the total hip and femoral neck between cohorts.

RESULTS

Adjusted changes in total hip and femoral neck BMD were - 4.16% (95% CI, - 4.87 to - 3.46%) and - 4.90% (95% CI, - 5.88 to - 3.92%) in BHS-7 participants; - 1.57% (95% CI, - 2.19 to - 0.96%) and - 0.99% (95% CI, - 1.88 to - 0.10%) in MOST participants; and statistically significant (P < 0.001) between-group differences in change were - 2.59% (95% CI, - 3.26 to - 1.91%) and - 3.91% (95% CI, - 4.83 to - 2.98%), respectively.

CONCLUSION

Hip fracture in older men is associated with accelerated BMD declines at the non-fractured hip that are greater than those expected during aging, and pharmacological interventions in this population to prevent secondary fractures may be warranted.

Difference in the trajectory of change in bone geometry as measured by hip structural analysis in the narrow neck, intertrochanteric region, and femoral shaft between men and women following hip fracture

Prior studies have shown that women have declines in bone structure and strength after hip fracture, but it is unclear whether men sustain similar changes. Therefore, the objective was to examine sex differences in proximal femur geometry following hip fracture. Hip structural analysis was used to derive metrics of bone structure and strength: aerial bone mineral density, cross-sectional bone area (CSA), cortical outer diameter, section modulus (SM), and buckling ratio (BR) from dual-energy x-ray absorptiometry scans performed at baseline (within 22days of hospital admission), two, six, or twelve months after hip fracture in men and women (n=282) enrolled in the Baltimore Hip Studies 7th cohort. Weighted estimating equations were used to evaluate sex differences at the narrow neck (NN), intertrochanteric (IT), and femoral shaft (FS). Men had significantly different one year NN changes compared to women in CSA: -6.33% (-12.47, -0.20) vs. 1.37% (-3.31, 6.43), P=0.049; SM: -4.98% (-11.08, 1.10) vs. 3.94% (-2.51, 10.42), P=0.042; and BR: 7.50% (0.65, 14.36) vs. -1.20% (-6.41, 4.00), P=0.044. One year IT changes displayed similar patterns, but the sex differences were not statistically significant for CSA: -4.07% (-10.83, 2.67) vs. 0.41% (-3.41, 4.24), P=0.252; SM: -4.78% (-12.10, 5.53) vs. -0.31 (-4.74, 4.11), P=0.287; and BR: 4.59% (-0.65, 9.84) vs. 1.52% (-4.23, 7.28), P=0.425. Differences in FS geometric parameters were even smaller in magnitude and not significantly different by sex. Women generally experienced non-significant increases in bone tissue and strength following hip fracture, while men had structural declines that were statistically greater at the NN region. Reductions in the mechanical strength of the proximal femur after hip fracture could put men at higher risk for subsequent fractures of the contralateral hip.