Sarcopenia and Osteoporosis

Daily Walking Accompanied with Intermittent Resistance Exercise Prevents Osteosarcopenia: A Large Cohort Study

BACKGROUND

This study aimed to analyze the effects of walking and resistance exercises on bone structure, bone mineral density (BMD), and skeletal muscle mass. We used data from the fourth Korean National Health and Nutrition Examination Survey (KNHANES).

METHODS

A total of 3,477 participants aged ≥19 years underwent hip structural analysis (HSA), BMD, and skeletal muscle index (SMI). All radiologic evaluations were performed using dual energy X-ray absorptiometry (DXA). The Korean short version of the International Physical Activity Questionnaire was used to measure physical activity status. The physical activity recommendations of the American College of Rheumatology Work Group Panel were used to evaluate the extent of activity.

RESULTS

The BMD and SMI in the group in which walking activity was performed 5 days or more per week for at least 30 min per day were significantly higher than those in the group in which walking activity was not performed. HSA and SMI in the group in which resistance exercise was performed 2 days or more per week for at least 30 min per day were found to be significantly higher than those in the group in which strengthening exercises were not performed.

CONCLUSIONS

If resistance exercise and walking are combined, bone loss and muscle loss are prevented maintaining cortical thickness in the elderly. Walking for more than 5 days a week and resistance exercise for more than 2 days a week will help to maintain the skeletal muscle as well as the cortex around the femur neck, thus helping to prevent fragility fractures in older individuals.

Early-senescent bone marrow mesenchymal stem cells promote C2C12 cell myogenic differentiation by preventing the nuclear translocation of FOXO3

AIMS

Mouse bone marrow mesenchymal stem cells (BMSCs) are pluripotent cells with self-renewal and differentiation abilities. Since the effects of senescent BMSCs on C2C12 cells are not fully clear, the present study aimed to elucidate these effects.

MAIN METHODS

Senescence-associated β-galactosidase staining and western blotting were performed to confirm the senescence of BMSCs. Immunofluorescence and western blotting were used to assess myoblast differentiation in each group. The role of the AKT/P70 signaling pathway and forkhead box O3 (FOXO3) nuclear translocation was explored by western blotting. BMSC-derived exosomes were injected into the tibialis anterior of mice, and RT-qPCR was used to assess the role of exosomes in promoting muscle differentiation.

KEY FINDINGS

Conditioned medium (CM) from early-senescent BMSCs promoted myogenic differentiation in vitro, which was detected as enhanced expression of myosin heavy chain (MHC), myogenin (MYOG), and myogenic differentiation 1 (MyoD). The AKT signaling pathway was found to be regulated by CM, which inhibited FOXO3 nuclear translocation. RT-qPCR analysis results showed that MHC, MyoD, and MYOG mRNA expression increased in the tibialis anterior of mice after exosome injection.

SIGNIFICANCE

The present study demonstrated that early-senescent BMSCs accelerated C2C12 cell myogenic differentiation, and the transcription factor, FOXO3, was the target of senescent cells. Collectively, our results suggest that the AKT/P70 signaling pathway mediates the effect of BMSCs on neighboring cells.

Association of Low Bone Mass with Decreased Skeletal Muscle Mass: A Cross-Sectional Study of Community-Dwelling Older Women

This study aimed to investigate the characteristics of skeletal muscle mass, muscle strength, and physical performance among community-dwelling older women. Data were collected from 306 older adults, and the data of 214 older women were included in the final analysis. Participants' calcaneus bone mass was measured using ultrasonography. Based on their T-scores, participants were divided into the following three groups: normal (T-score > -1), low (-2.5 < T-score ≤ -1), and very low (T-score ≤ -2.5) bone mass. Further, participants' skeletal muscle mass, muscle strength (grip and knee extension strength), and physical performance [gait speed and timed up and go (TUG)] were measured. Arm skeletal muscle index (SMI, skeletal muscle mass/height2), leg SMI, and appendicular SMI in the very low bone mass group were low compared to those of the low bone mass group (p = 0.034, p = 0.011, and p = 0.009, respectively). Grip and knee extension strength, gait speed, and TUG were not significantly different between the groups. These findings suggest that older women with low bone density had decreased skeletal muscle mass. Therefore, maintaining or improving skeletal muscle mass may prevent low bone mass.

Sarcopenia and Hip-Structure Analysis Variables in Korean Elderly Population

The purpose of this study is comparing the hip-structure analysis (HSA) variables with the skeletal muscle index (SMI) in elderly patients with sarcopenia using nationwide representative data on the Republic of Korea (ROK). The survey data were collected from household interviews and direct standardized physical examinations conducted in specially equipped mobile examination centers. The data were collected in 2008 from 9744 participants. Patients under 65 years of age who were without data on the skeletal-muscle-mass and HSA variables were excluded. After these exclusions, a total of 744 participants (293 men and 451 women) were ultimately analyzed. The HSA measurements of the hip-bone geometry were analyzed using dual-energy X-ray absorptiometry. The appendicular SMI is defined as the sum of the arm and leg SMIs. Sarcopenia is defined according to the criteria for the Asia Working Group for Sarcopenia as SMIs of less than 5.4 kg/m² and 7.0 kg/m² for women and men, respectively. In the entire population, SMI was found to be positively correlated to HSA variables. After adjusting for age, body mass index, and energy intake in both the women and men groups, a statistically significant difference became evident in all variables between the SMI and the HSA. The present study suggests that skeletal-muscle loss negatively affects hip-bone-strength indices in elderly sarcopenia patients. Implementing strategies to increase SMI in the elderly population may be useful for reducing the vulnerability to hip fracture.

An Objective and Reliable Method for Identifying Sarcopenia in Lumbar Spine Surgery Patients: Using Morphometric Measurements on Computed Tomography Imaging

Study Design

A retrospective observational study.

Purpose

Establish a quantifiable and reproducible measure of sarcopenia in patients undergoing lumbar spine surgery based on morphometric measurements from readily available preoperative computed tomography (CT) imaging.

Overview of Literature

Sarcopenia—the loss of skeletal muscle mass—has been linked with poor outcomes in several surgical disciplines; however, a reliable and quantifiable measure of sarcopenia for future assessment of outcomes in spinal surgery patients has not been established.

Methods

A cohort of 90 lumbar spine fusion patients were compared with 295 young, healthy patients obtained from a trauma da¬tabase. Cross-sectional vertebral body (VB) area, as well as the areas of the psoas and paravertebral muscles at mid-point of pedicles at L3 and L4 for both cohorts, was measured using axial CT imaging. Total muscle area-to-VB area ratio was calculated along with intraclass correlation coefficients for interobserver and intraobserver reliability. Finally, T-scores were calculated to help identify those patients with considerably diminished muscle-to-VB area ratios.

Results

Both muscle mass and VB areas were considerably larger in males compared with those in females, and the ratio of these two measures was not enough to account for large differences. Thus, a gender-based comparison was made between spine patients and healthy control patients to establish T-scores that would help identify those patients with sarcopenia. The ratio for paravertebral muscle area-to-VB area at the L4 level was the only measure with good interobserver reliability, whereas the other three of the four ratios were moderate. All measurements had excellent correlations for intraobserver reliability.

Conclusions

We postulate that a patient with a T-score <−1 for total paravertebral muscle area-to-VB area ratio at the L4 level is the most reliable method of all our measurements that can be used to diagnose a patient undergoing lumbar spine surgery with sarcopenia.

A view at sarcopenia by endocrinologist

Sarcopenia is one of the syndromes that significantly affects the health and life of the patient. Sarcopenia is a polyetiological syndrome with a complex, insufficiently studied pathogenesis, in which endocrine factors play a leading role. Comorbidity of elderly patients creates difficulties in differential diagnosis of existing pathology. The combination of sarcopenia with various endocrine pathologies, such as obesity, osteoporosis, hypothyroidism, hypoparathyroidism, vitamin D deficiency leads to a more severe course of disease and a worse prognosis for the quality and life expectancy of the patient. In this case, in some situations, the patient's condition can be improved by assessing pathogenetic causes and their elimination. Thus, the endocrinologist should pay more attention to the sarcopenia syndrome and its correction, as well as for its prevention at the earliest stages.

Sarcopenia and Its Clinical Correlates in the General Population: The Rotterdam Study

Sarcopenia, a complex multifactorial condition, is characterized by loss of muscle mass and function, which increases progressively with age. The existence of different definitions has contributed to the large variation in the prevalence estimates of sarcopenia. We aimed to estimate the prevalence of sarcopenia in the general population using the European Working Group on Sarcopenia in Older People (EWGSOP) proposed definition and compared baseline demographic and clinical characteristics between the nonsarcopenia, presarcopenia, and sarcopenia individuals, with particular emphasis on the overlap with osteoporosis and fracture risk. We studied 5911 subjects at a mean age of 69.2 years (55.8% female) with data on sarcopenia participating in the Rotterdam Study, a prospective population-based cohort study in Rotterdam, the Netherlands. Presarcopenia was defined as having only low muscle mass, whereas sarcopenia was defined based on the presence of low muscle mass, plus either low muscle strength or low physical performance. The prevalence of presarcopenia and sarcopenia was 5.9% and 4.4%, respectively. Individuals with sarcopenia were older, more often males, smokers, with less optimal dietary intake, and more often disabled with lower physical activity. Although the prevalence of fractures was higher in individuals with low lean mass (presarcopenic [16.6%] and sarcopenic [23.5%]) compared with the no sarcopenic group (15.5%), the differences were not present after correcting for age and sex. There were no statistical differences in the prevalence of chronic diseases, with the exception of a higher prevalence of COPD in presarcopenic (29.1%) and sarcopenic (26.9%) individuals compared with nonsarcopenic (13.4%) individuals. Osteoporotic individuals with (odds ratio [OR] = 2.59, 95% confidence interval [CI] 1.41-4.45) and without sarcopenia (OR = 2.75, 95% CI 2.01-3.75) had similar elevated risk of nonvertebral fractures. The presence of sarcopenia appears to be independent of chronic diseases with the exception of COPD and more related to lifestyle factors and disabilities. Sarcopenic individuals in the general population are at no greater risk of fracture than what is determined by their low bone mineral density. © 2018 American Society for Bone and Mineral Research.

New Skeletal Muscle Mass Index in Diagnosis of Sarcopenia

Background

We sought to develop a novel index based on the skeletal muscle mass that reflects the change of quality of life (QOL), and is the most appropriate index for the body composition of the elderly in Korea. Whether lower extremity skeletal muscle mass index (LESMI) is an appropriate novel new index to diagnose patients with sarcopenia was also evaluated. A cut-off value for each index was reported to facilitate the diagnosis of patients with sarcopenia in a Korean population.

Methods

We used the 5th Korean National Health and Nutrition Examination Survey data from 2010. We analyzed 409 elderly patients, including 231 men and 178 women, aged ≥65 years. Patients were diagnosed by calculating their skeletal muscle index based on the skeletal muscle mass measured using dual energy X-ray absorptiometry. Obesity and osteoporosis were used to screen data and EuroQOL-5 dimension as a health questionnaire.

Results

The prevalence of sarcopenia in each index was obtained based on its cut-off value for diagnosing sarcopenia. There was a significant difference between the obesity rate of elderly patients diagnosed with sarcopenia and those who were not based on each index. There was no significant difference in the prevalence of osteoporosis between the groups. Sarcopenia diagnosis based on the LESMI was significantly correlated with QOL.

Conclusions

LESMI, a novel index based on skeletal muscle mass, reflects changes in QOL and is appropriate for the body composition of elderly people in Korea.

Combination of measures of handgrip strength and red cell distribution width can predict in-hospital complications better than the ASA grade after hip fracture surgery in the elderly

BACKGROUND

Early detection of a high-risk patient following hip fracture surgery is of paramount clinical importance. American Society of Anesthesiologists (ASA) grading is an easy and efficient index in predicting a worse outcome. The red cell distribution width (RDW) and handgrip strength, are gaining interest as a prediction tool as well. Accordingly, the objective of this study was to investigate the potential association between ASA, RDW and grip strength and detect the effects of combining RDW and grip strength for predicting early complication after hip fracture surgery in the elderly.

METHODS

Eighty-three consecutive patients operated with hip fracture surgeries were identified retrospectively. Age, gender, diagnosis, RDW, handgrip strength and ASA grade were recorded. Admission to the intensive care unit (ICU), length of ICU stay, transfer to other departments, in-hospital death, and readmission were investigated as early complications. Logistic regression analysis was applied to evaluate the estimates in predicting complications, and receiver operating characteristics curves were constructed to compare the estimates and decide which method is more accurate.

RESULTS

After the surgery, 52% of the patients were admitted to the ICU. From the analyses, RDW and grip strength had no significant relation with each other. However, the ICU stay was correlated with RDW and grip strength but not for the ASA grade. A higher ASA grade and grip strength could independently predict ICU admission. The combination of RDW with grip strength outweighed the ASA grade in predictive ability.

CONCLUSIONS

The current study indicated that combining RDW and grip strength measures can be efficient and clinically relevant in predicting early postoperative complications after fragility hip fracture in the elderly. Due to the objectivity and availability of those two approaches, patient care, and functional outcomes are expected to be improved by adopting these measures in the clinical setting.

Does femoral offset recover and affect the functional outcome of patients with displaced femoral neck fracture following hemiarthroplasty?

BACKGROUND

Restoring preoperative horizontal femoral offset (FO) promised good functional outcome in patients receiving total hip arthroplasty. However, relatively little was known regarding the clinical relevance of restoring the offset in patients with bipolar hemiarthroplasty to treat displaced femoral neck fracture. Therefore, the objective of this study was to evaluate postoperative FO accurately and verify its relation with functional outcome.

METHODS

One hundred elderly patients who received bipolar hemiarthroplasty to treat displaced femoral neck fracture were identified. Preoperative CT scanning of contralateral hip joint and reconstruction of images led to rotation-free FO. By referencing postoperative implant specification and comparing to measured values in Picture Archive and Communication System, rotation-free postoperative FO and the amount of change were acquired. Postoperative Harris Hip Score (HHS) and Modified Barthel Index (MBI) were evaluated to measure functional outcome at 12-month after the surgery. Patients with significant FO change were identified. Multiple regression analysis was conducted to determine if the FO change might independently affect the outcome regardless of confounding factors.

RESULTS

The mean preoperative offset was 37.4±2.5 increased by 12.7±9.6% after the surgery. Only 25.0% of postoperative offset after hemiarthroplasty was changed within ±5% of preoperative offset. A total of 45.0% of postoperative offset changed within ±10% while 77.0% of postoperative offset changed within ±20%. 23% of patients whose FO changed more than 20% showed significantly worse outcome score than the patients whose FO change remained within ±20% of initial value. Mean MBI and HHS were negatively correlated with FO change. After adjusting for confounding factors, significant correlation remained between modification of FO and MBI, but not between FO change and HHS (B=4.576; β=0.235; 95% confidence interval of B: 0.534 to 8.135).

CONCLUSIONS

FO was not properly restored in 23% of subjects receiving bipolar hemiarthroplasty due to femoral neck fracture. FO restoration independently predicted fair MBI after the surgery. Therefore, surgeons should pay attention to restoring FO with meticulous templating.

ACTN3 Gene and Susceptibility to Sarcopenia and Osteoporotic Status in Older Korean Adults

BACKGROUND

Little information is available about molecular markers for sarcopenia and osteoporosis in Asian populations.

OBJECTIVE

This study investigated the association of the ACTN3 polymorphism with sarcopenia and osteoporotic status in older Korean adults.

METHODS

Older Korean 62 men and 270 women (mean age 73.7 ± 6.6 years) participated in this study. Body mass index, percent body fatness, appendicular skeletal muscle mass, and bone mineral density of the lumbar spine, femur, and total body were analyzed with dual-energy X-ray absorptiometry. ACTN3 R/X genotyping was determined using TaqMan probes.

RESULTS

Determination of odds ratios (ORs) and 95% confidence intervals (CIs) using binary logistic regression analyses showed that XX homozygotes were at a significantly higher risk of sarcopenia (OR = 2.056, 95%  CI = 1.024-4.127, p = 0.043) and osteoporosis (OR = 2.794, 95%  CI = 1.208-5.461, p = 0.016) than RR homozygotes (reference group, OR = 1). The OR of XX homozygotes for having sarcopenia remained significant (OR = 2.237, 95%  CI = 1.044-4.836, p = 0.038) after adjustments for age, gender, body fatness, and serum vitamin D. The OR of XX homozygotes for having osteoporosis was no longer significant (OR = 2.682, 95%  CI = 0.960-7.942, p = 0.075) after adjustments for the covariates.

CONCLUSION

Our findings suggest that the ACTN3 R577X genotype may influence decline in muscle and bone health phenotypes in older Korean adults.