Longitudinal changes in body composition and diet after acute spinal cord injury

OBJECTIVE

Spinal cord injury (SCI) is associated with low muscle mass and adiposity, however, to our knowledge, few studies have monitored the trajectory of changes over time. This study aimed to evaluate the timing, rate, magnitude, and site-specific changes in body composition and related changes in diet after SCI.

METHODS

We assessed 39 patients with SCI. The analysis included five women. Of the participants, 51% had American Spinal Injury Association Impairment Scale (AIS) criteria A/B (motor complete) injuries, 18% had AIS C (sensory/motor incomplete) injuries, and 31% had AIS D (motor incomplete) injuries. The mean age of the patients was 43.2 y. They were 48.1 d post-injury and had their weight, diet, and body composition (bioimpedance spectroscopy) assessed every 2 wk.

RESULTS

No significant linear changes were observed for any body composition measure. Total body fat mass (FM) changed 0.01 kg/2 wk when fitted to a quadratic model (P = 0.004), decreasing to week 15 and returning to baseline at week 28. Subgroup analysis revealed that arm lean tissue mass (LTM) increased in paraplegic versus tetraplegic participants (0.05 versus -0.01 kg/2 wk, P = 0.007). Participants with AIS A/B injuries lost FM (-0.17 kg; P = 0.010), whereas those with AIS C injuries gained appendicular LTM (ALTM; 0.15 kg; P = 0.017) and leg LTM (0.12 kg; P = 0.008) every 2 wk. Body composition remained stable in the AIS D group. Mean fortnightly changes were greater in the AIS A/B group than the C group for weight (mean difference -0.30 kg; P = 0.021), FM (-0.25 kg; P = 0.002), and leg LTM (-0.11 kg; P = 0.021) and AIS A/B versus D for FM (-0.42 kg; P = 0.013). Baseline energy and protein intakes were 2150 kcal (±741) and 102 g (±40) and decreased by 21.5 kcal (P = 0.016) and 1.3 g (P = 0.004) every 2 wk but were not associated with body composition changes.

CONCLUSIONS

Neurologic level and severity of SCI, but not changes in diet, were the main determinants of heterogeneous body composition changes.

Associations of Lean Mass, Muscular Strength, and Physical Function with Trabecular Bone Score in Older Adults

INTRODUCTION/BACKGROUND

Trabecular bone score (TBS) is an indirect measurement of bone quality and microarchitecture determined from dual-energy X-ray absorptiometry (DXA) imaging of the lumbar spine. TBS predicts fracture risk independent of bone mass/density, suggesting this assessment of bone quality adds value to the understanding of patients' bone health. While lean mass and muscular strength have been associated with higher bone density and lower fracture risk among older adults, the literature is limited regarding the relationship of lean mass and strength with TBS. The purpose of this study was to determine associations of DXA-determined total body and trunk lean mass, maximal muscular strength, and gait speed as a measure of physical function, with TBS in 141 older adults (65-84 yr, 72.5 +/- 5.1 yr, 74% women).

METHODOLOGY

Assessments included lumbar spine (L1-L4) bone density and total body and trunk lean mass by DXA, lower body (leg press) and upper body (seated row) strength by one repetition maximum tests, hand grip strength, and usual gait speed. TBS was derived from the lumbar spine DXA scan. Multivariable linear regression determined the contribution of proposed predictors to TBS.

RESULTS

After adjusting for age, sex, and lumbar spine bone density, upper body strength significantly predicted TBS (unadjusted/adjusted R2= 0.16/ 0.11, β coefficient =0.378, p=0.005), while total body lean mass index showed a trend in the expected direction (β coefficient =0.243, p=0.053). Gait speed and grip strength were not associated with TBS (p>0.05).

CONCLUSION

Maximum strength of primarily back muscles measured as the seated row appears important to bone quality as measured by TBS, independent of bone density. Additional research on exercise training targeting back strength is needed to determine its clinical utility in preventing vertebral fractures among older adults.

Altered bone and body composition in children and adolescents with confirmed prenatal alcohol exposure

Prenatal alcohol exposure can contribute to long term adverse health outcomes. Development of the skeletal system begins at the early embryonic stage and continues into early adulthood but the effect of prenatal alcohol exposure on skeletal growth is relatively unexplored in a clinical population. Here, we performed dual X-ray absorptiometry to examine bone, fat, and muscle accrual in children and adolescents diagnosed with, or at risk of, fetal alcohol spectrum disorders (FASDs). Children (aged 4-9 years) with FASD or at risk of FASD (n = 10) had similar growth to age matched controls (n = 27). By adolescence (aged ≥10 years), those with FASDs (n = 13) were shorter and had lower areal bone mineral density and lean tissue mass than typically developing peers (n = 29). Overall, adolescents diagnosed with FASDs had greater odds of impairments to bone and body composition. These findings highlight the importance of early FASD diagnosis and appropriate post-diagnostic medical follow-up to enable timely, effective interventions to optimize bone and body composition during paediatric growth.

Muscle strength performed better than muscle mass in identifying cognitive impairment risk in maintenance hemodialysis patients

OBJECTIVES

The association between muscle mass and cognitive impairment (CI) is conflicting. We aimed to evaluate and compare the associations of muscle strength, muscle mass and CI risk in maintenance hemodialysis (MHD) patients.

METHODS

We conducted a multicenter, cross-sectional study. Cognitive function was assessed with the Mini-Mental State Examination (MMSE) score. Muscle strength was assessed by hand grip strength (HGS), muscle mass was assessed by lean tissue mass (LTM). Education status was divided into two groups: lower education status (senior middle school and below) and higher education status (high school and above). Multivariable logistic regression models and subgroup analyses were performed. Receiver-operating characteristic (ROC) analyses were conducted to compare their predictive power in discriminating CI.

RESULTS

2827 adult MHD patients were included in our final analysis. Patients in the lowest quartile of HGS was 2.82-fold as likely to have CI as compared to those in the highest quartile, while participants in the lowest quartile of LTM group were 1.52-fold as likely to have CI, when compared with the highest quartile group of LTM after adjusting for age, gender and education level. The association persisted in all subgroups except for women and well-educated participants. There was a significant interaction between HGS and education status on CI and age played an interactive role in the association between LTM and incident CI (P for interaction < 0.05). The AUC value of the HGS was significantly higher than that of LTM (0.69 VS 0.63, P < 0.001).

CONCLUSIONS

Muscle strength performed better than muscle mass in identifying individuals at high risk of CI, particularly in male and less educated Chinese MHD patients.

LEVEL OF EVIDENCE

Level V, cross-sectional study.

Effects of Roux-en-Y Gastric Bypass Versus Sleeve Gastrectomy on Body Composition for Patients with a BMI > 35 kg/m2 at 1 Year After Surgery

PURPOSE

Effects of Roux-en-Y gastric bypass (RYGB) versus sleeve gastrectomy (SG) on body composition have not been well compared. This meta-analysis aimed to compare changes in fat mass (FM) and lean tissue mass (LTM) for patients with a BMI > 35 kg/m² at 1 year after RYGB and SG.

METHODS

PubMed, EMBASE, the Cochrane Library, and ClinicalTrials.gov were searched ending in December 2021 for eligible studies which reported baseline and postsurgical BMI, FM, and LTM.

RESULTS

Of 17 eligible studies, 831 patients were included, 484 following RYGB and 347 following SG. Weighted mean differences (WMD) and 95% confidence intervals (CI) were from a random-effects model. For patients with a BMI > 35 kg/m², RYGB resulted in a more substantial reduction of BMI (- 14.13 kg/m² [95%CI - 14.74, - 13.53] versus - 11.96 kg/m² [95%CI - 12.81, - 11.11], P < 0.001) and FM (- 26.22 kg [95%CI - 28.31, - 24.12] versus - 21.50 kg [95%CI - 25.52, - 17.48], P = 0.042) than SG, and a relatively weaker impact on LTM (- 8.28 kg [95%CI - 9.33, - 7.22] versus - 10.12 kg [95%CI - 11.55, - 8.68], P = 0.043).

CONCLUSION

This meta-analysis study indicates that RYGB is superior to SG in reducing excess FM for patients with a BMI > 35 kg/m² and seems to be more beneficial when LTM preservation is taken into consideration.

Acute and longer-term body composition changes after bariatric surgery

BACKGROUND

Bariatric surgery induces weight loss but its acute and longer-term effects on body composition (BC) are largely unknown.

OBJECTIVES

To determine the BC changes in obese French patients after sleeve gastrectomy (SG) at 1 and 12 months.

SETTING

Obesity Reference Center, University Hospital of Montpellier, France.

METHODS

Whole and localized BC (lean tissue mass [LTM] and fat mass [FM]) and abdominal adiposity, including total adipose tissue, visceral adipose tissue, and subcutaneous adipose tissue, were determined by dual-energy X-ray absorptiometry in 30 obese patients (25 women, 83.3%) just before SG and 1 and 12 months later.

RESULTS

The mean weight loss was -9.7 ± 2.6 kg at 1 month and -32.1 ± 10.3 kg at 12 months. This weight loss was due to an equivalent decrease in LTM and FM in the acute phase, while FM loss appeared to be the main cause in the chronic phase. For each component (LTM and FM), the loss was relatively homogeneous across sites. Compared with the presurgical values, android and gynoid tissue and total adipose tissue, visceral adipose tissue, and subcutaneous adipose tissue changed significantly over the 12-month period. No basal clinical parameter was predictive of the variation in LTM, whereas age and the whole-body LTM/FM ratio were associated with the decrease in FM.

CONCLUSION

This study demonstrates that SG induces a clear modification in BC, characterized by a decrease in LTM in the acute phase and sustained FM loss in the first year. These results suggest that the early phase should be targeted for strategies to reduce LTM loss, which is a longer-term weight-regain criterion. Further studies to investigate the potential advantages of visceral adipose tissue compared with whole-body FM for improving post-SG co-morbidities should be performed.

High baseline fat mass, but not lean tissue mass, is associated with high intensity low back pain and disability in community-based adults

Objectives

Low back pain is the largest contributor to disability worldwide. The role of body composition as a risk factor for back pain remains unclear. Our aim was to examine the relationship between fat mass and fat distribution on back pain intensity and disability using validated tools over 3 years.

Methods

Participants (aged 25–60 years) were assessed at baseline using dual-energy X-ray absorptiometry (DXA) to measure body composition. All participants completed the Chronic Pain Grade Scale at baseline and 3-year follow-up. Of the 150 participants, 123 (82%) completed the follow-up.

Results

Higher baseline body mass index (BMI) and fat mass (total, trunk, upper limb, lower limb, android, and gynoid) were all associated with high intensity back pain at either baseline and/or follow-up (total fat mass: multivariable OR 1.05, 95% CI 1.01–1.09, p < 0.001). There were similar findings for all fat mass measures and high levels of back disability. A higher android to gynoid ratio was associated with high intensity back pain (multivariable OR 1.04, 95% CI 1.01–1.08, p = 0.009). There were no associations between lean mass and back pain.

Conclusions

This cohort study provides evidence for the important role of fat mass, specifically android fat relative to gynoid fat, on back pain and disability.

How much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution

Controversy exists about the maximum amount of protein that can be utilized for lean tissue-building purposes in a single meal for those involved in regimented resistance training. It has been proposed that muscle protein synthesis is maximized in young adults with an intake of ~ 20-25 g of a high-quality protein; anything above this amount is believed to be oxidized for energy or transaminated to form urea and other organic acids. However, these findings are specific to the provision of fast-digesting proteins without the addition of other macronutrients. Consumption of slower-acting protein sources, particularly when consumed in combination with other macronutrients, would delay absorption and thus conceivably enhance the utilization of the constituent amino acids. The purpose of this paper was twofold: 1) to objectively review the literature in an effort to determine an upper anabolic threshold for per-meal protein intake; 2) draw relevant conclusions based on the current data so as to elucidate guidelines for per-meal daily protein distribution to optimize lean tissue accretion. Both acute and long-term studies on the topic were evaluated and their findings placed into context with respect to per-meal utilization of protein and the associated implications to distribution of protein feedings across the course of a day. The preponderance of data indicate that while consumption of higher protein doses (> 20 g) results in greater AA oxidation, this is not the fate for all the additional ingested AAs as some are utilized for tissue-building purposes. Based on the current evidence, we conclude that to maximize anabolism one should consume protein at a target intake of 0.4 g/kg/meal across a minimum of four meals in order to reach a minimum of 1.6 g/kg/day. Using the upper daily intake of 2.2 g/kg/day reported in the literature spread out over the same four meals would necessitate a maximum of 0.55 g/kg/meal.

The effect of hydration status on the measurement of lean tissue mass by dual-energy X-ray absorptiometry

PURPOSE

Athletes cycle between exercise and recovery. Exercise invokes changes in total body water from thermal sweating, muscle and hepatic glycogen depletion and metabolic water loss. Recovery from exercise results in rehydration, substrate repletion, and possible glycogen supercompensation. Such changes may corrupt the measurement of hydrated tissues, such as lean tissue mass (LTM), by dual-energy X-ray absorptiometry (DXA). The purpose of this study was to determine the effect of exercise and thermal dehydration and subsequent glycogen supercompensation on DXA-based measurement of body composition.

METHODS

Twelve active adult (18-29 years) males exercised at 70% VO_2max on a cycle ergometer in a thermal environment (30 °C) to induce a 2.5% reduction in body mass. Participants subsequently underwent a glycogen supercompensation phase, whereby a high carbohydrate diet (8-12 g/kg body mass/day) was consumed for a 48-h period. Whole-body DXA measurement was performed at baseline, following exercise and supercompensation.

RESULTS

Following exercise, mean body mass decreased by -1.93 kg (95% CI -2.3, -1.5), while total LTM decreased by -1.69 kg (-2.4, -1.0). Supercompensation induced a mean body mass increase of 2.53 kg (2.0, 3.1) and a total LTM increase of 2.36 kg (1.8, 2.9). No change in total fat mass or bone mineral content was observed at any timepoint.

CONCLUSIONS

Training regimens that typically induce dehydration and nutrition regimens that involve carbohydrate loading can result in apparent changes to LTM measurement by DXA. Accurate measurement of LTM in athletes requires strict observation of hydration and glycogen status to prevent manipulation of results.

Body composition changes in the first month after sleeve gastrectomy based on gender and anatomic site

BACKGROUND

Sleeve gastrectomy (SG) induces acute weight loss, but its impact on the very early postoperative changes in body composition (BC) is less clear.

OBJECTIVES

This longitudinal study examined the BC changes in the first month after SG according to gender and anatomic site.

METHODS

BC (lean tissue mass [LTM] and fat mass [FM]) were determined by dual-energy x-ray absorptiometry in 41 obese patients (33 women, 80.5%) just before SG and 1 month later.

SETTING

University hospital of Montpellier, France.

RESULTS

One month after SG, mean weight loss was -9.8±2.6 kg, with a significant decrease in LTM and FM (kg) ranging from -7.3% to 9.5%, depending on site. FM (kg) loss in men exceeded that in women at whole body, upper limbs, and trunk. FM (%) and the LTM/FM ratio decreased only in the trunk in men and the lower limbs in women, but the gender difference was only observed for the trunk. In women, age was positively correlated with relative FM variation (% and kg) in the lower limbs and negatively correlated with LTM and LTM/FM. In men, weight was negatively correlated with the relative LTM and FM (kg) variations in the upper limbs.

CONCLUSION

SG induces acute weight loss, but this loss comprises losses in both FM and LTM. Because excessive LTM loss can have deleterious consequences, preventive strategies should be implemented soon after bariatric surgery. The specific changes in BC are highlighted according to gender and anatomic site.

A study investigating short- and medium-term effects on function, bone mineral density and lean tissue mass post-total knee replacement in a Caucasian female post-menopausal population: implications for hip fracture risk

Significant increased hip fracture incidence has been reported in the year following total knee replacement. This study demonstrates that bone and muscle loss is a post-surgical consequence of total knee replacement, alongside poor outcomes in function and activity potentially contributing to reduced quality of life and increased hip fracture risk.

INTRODUCTION

A significant increase in hip fracture incidence in the year following total knee replacement (TKR) surgery has been reported. This study investigated function and activity following TKR and the effects of limited mobility on bone and muscle loss and their potential contribution to hip fracture risk.

METHODS

Changes in dual-energy X-ray absorptiometry (DXA) (GE Lunar Prodigy, Bedford MA), bone mineral density (BMD) at the neck of femur (NOF), total hip region (TH) and lumbar spine were measured alongside leg lean tissue mass (LLTM) in post-menopausal Caucasian females following TKR (N = 19) compared to controls (N = 43). Lumbar spine trabecular bone scores (TBSs) were calculated. Ipsilateral/contralateral weight bearing, lower limb function, 3-day pedometer readings, pain levels and falls were also recorded. Measurements were obtained at pre-surgery baseline and at 6 weeks, 6 months and 12 months post-surgery.

RESULTS

No statistically significant differences were demonstrated between groups at baseline bilaterally in LLTM or BMD at the NOF and TH. Losses in ipsilateral NOF and TH BMD and contralateral LLTM were significantly higher in the TKR group at 6 months. Impairment in function and weight bearing persisted in the TKR group 12 months post-operatively alongside deficits in bilateral muscle mass and ipsilateral NOF and TH BMD. Falls incidence was not significantly higher in the TKR group.

CONCLUSIONS

Bone loss at the hip with associated muscle loss is a consequence of TKR that, in addition to poor patient outcomes in function and activity, potentially contributes to increased hip fracture risk in the year following surgery.

Predicting sarcopenia from functional measures among community-dwelling older adults

Sarcopenia is defined as age-related lean tissue mass (LTM) loss resulting in reduced muscular strength, physical function, and mobility. Up to 33 % of older adults currently are sarcopenic, with likely many more undiagnosed. The purpose of this investigation was to predict sarcopenia status from easily accessible functional measures of community-dwelling older adults. Forty-three community-dwelling older adults (n = 32 females and n = 11 males) participated in the present investigation. Inclusion criteria included ≥65 years of age, mini-mental state examination score ≥24, and no falls within previous 12 months. All subjects completed their appendicular skeletal mass (ASM) assessment via dual-energy X-ray absorptiometry (DXA) and were categorized as either sarcopenic or non-sarcopenic. Physical assessments included 10-m usual walk, hand-grip (HG) strength, 6-min walk, 8-ft up-and-go, 30-s chair stand, 30-s arm curl, and sit-to-stand muscular power. A forward, stepwise multiple regression analysis revealed that age, sex, weight, height, 10-m walk, HG, and sit-to-stand muscular power account for 96.1 % of the variance in ASM. The area under the curve was 0.92 for correctly identifying sarcopenic participants compared to their actual classification. This is the first prediction model used to identify sarcopenia based on parameters of demographic and functional fitness measures in community-dwelling older adults. The ability to accurately identify sarcopenia in older adults is imperative to their quality of life and ability to perform activities of daily living.

Lean tissue mass and energy expenditure are retained in hypogonadal men with spinal cord injury after discontinuation of testosterone replacement therapy

OBJECTIVE

To determine whether favorable changes to lean tissue mass (LTM), resting energy expenditure (REE), and testosterone (T) that occurred with 12 months of physiological testosterone replacement therapy (TRT) were retained 6 months after discontinuing treatment.

DESIGN

Prospective, open-label, controlled drug intervention trial.

SETTING

Metropolitan area hospitals.

SUBJECTS

Eugonadal (n = 11) and hypogonadal (n = 13) men with chronic spinal cord injury (SCI).

INTERVENTIONS

Hypogonadal subjects received a 5 or 10 mg transdermal T patch daily for 12 months, with adjustment of the dose to normalize the serum T concentration; TRT was discontinued after 12 months (TRT-12M) and subjects were followed for an additional 6 months and re-evaluated (Post-TRT). Total body dual energy X-ray absorptiometry and blood draws were performed at baseline (BL) prior to TRT, TRT-12M, and Post-TRT. Eugonadal subjects did not receive treatment and were evaluated at comparable time points.

RESULTS

There were no significant differences between groups prior to TRT at BL for any of the study endpoints. In the hypogonadal group, a significant increase in LTM was observed from BL to TRT-12M (50.2 ± 7.4 vs. 52.9 ± 6.8 kg, P < 0.01), which persisted Post-TRT compared to BL (52.2 ± 7.8 kg, P < 0.05). The increase in REE from BL to TRT-12M (1283 ± 246 vs. 1410 ± 250 kcal/day) was also retained at Post-TRT (1393 ± 220 kcal/day). These sustained improvements in LTM and REE after termination of anabolic hormonal therapy may be associated with persistent beneficial effects on health and physical function of hypogonadal men with chronic SCI.

Body composition of women and men with complete motor paraplegia

OBJECTIVES

To examine body composition, including the relationship between body mass index (BMI) and total body fat, in women and men with complete motor paraplegia and to make comparisons with able-bodied controls.

METHODS

In 13 subjects with traumatic, complete motor paraplegia (six women, seven men) and 39 sex-, age-, and BMI-matched controls from the community (18 women, 21 men), we measured total and regional (upper extremities, trunk, and lower extremities) lean and fat mass using total body dual-energy X-ray absorptiometry.

RESULTS

Both women and men with paraplegia had significantly lower lean mass in their lower extremities, as would be expected, and in their total body when compared with controls. However, they had significantly greater lean mass in their upper extremities than controls (4.4 kg vs. 3.6 kg, P = 0.004 and 8.6 kg vs. 6.7 kg, P < 0.001 in women and men, respectively); all subjects with paraplegia studied used manual wheelchairs. Although total body fat mass was significantly greater in women (P = 0.010) and men (P = <0.001) with paraplegia compared with controls, for the equivalent total body fat mass, BMI was actually lower in women and men with paraplegia than controls (e.g. 20.2 kg/m² vs. 25.0 kg/m², respectively).

CONCLUSION

We report on body composition in persons with complete motor paraplegia, including women on whom limited information is currently available. Our results support the need to define better assessments of obesity in both women and men following spinal cord injury, particularly of central body fat distribution, as BMI underestimates adiposity in this population.