Decrease of Muscle Mass in Young Patients With Neuromuscular Disease: Assessment of Sarcopenia

The association between eight complete blood count-derived inflammatory markers and muscle health

Background

Most studies have evaluated sarcopenia and muscle health solely based on muscle mass. This study comprehensively examined the associations between eight inflammatory indicators and muscle mass and strength, with the aim of identifying an indicator capable of evaluating muscle health across multiple dimensions.

Methods

This study included 10,440 participants from the National Health and Nutrition Examination Survey (NHANES, 2011-2018) and 5,384 participants from NHANES (2011-2014). Multivariate logistic regression, smooth curve fitting, restricted cubic spline (RCS) analysis, subgroup analysis, and Spearman's correlation were used to comprehensively assess the associations between the eight inflammatory indicators and muscle mass and strength. Receiver operating characteristic (ROC) curves were used to compare the predictive abilities of the different indices for low muscle mass and muscle strength. Additionally, NHANES data were cross-validated with data from 554 patients at our hospital to evaluate the ability of the systemic immune inflammatory index (SII) to distinguish between low muscle mass and strength.

Results

After controlling for all potential confounding factors, multiple logistic regression analysis revealed that apart from the platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), and derived NLR (dNLR), the neutrophil-to-monocyte-plus-lymphocyte ratio (NMLR), neutrophil-to-lymphocyte ratio (NLR), SII, systemic inflammation response index (SIRI), and pan-immune-inflammation value (PIV) were significantly negatively correlated with muscle mass and strength. However, NMLR and NLR were significantly associated with changes in muscle mass only in Q4 (P < 0.05). In the stratified analysis by body mass index (BMI), only the SII, NLR, and NMLR were unaffected by BMI. In the cross-validation, the predictive performance of the SII for low muscle mass [area under the curve (AUC) = 0.699, 0.677, and 0.685] and low muscle strength (AUC = 0.857, 0.849, and 0.840) demonstrated a good reference value. RCS and smooth curve fitting analyses indicated that most inflammatory markers were linearly correlated with muscle health (P < 0.05).

Conclusion

Compared with other inflammatory markers (e.g., PIV and dNLR), the SII demonstrated a more robust predictive ability, was less influence by covariates, and exhibited high generalization performance in internal and external validation. SII may be crucial in identifying "hidden sarcopenia" and the early stages of muscle functional decline.

Prevalence of and risk factors for sarcopenia in patients with epilepsy

BACKGROUND

Epilepsy is a chronic neurological disorder with a burden of comorbidities. Knowledge regarding sarcopenia prevalence and associated risk factors in patients with epilepsy remains limited, which prompted us to conduct the present study.

METHODS

This cross-sectional study enrolled patients with epilepsy from our epilepsy clinic and controls from the staff at National Cheng Kung University Hospital, Tainan, Taiwan. Sarcopenia was defined using the criteria outlined by the 2019 Asian Working Group for Sarcopenia and the 2010 European Working Group on Sarcopenia in Older People. Muscle mass (skeletal muscle mass index) was measured through bioelectrical impedance, muscle strength was assessed using hand grip tests, and physical performance was evaluated using the 6-m walk test. Hormone (testosterone, growth hormone, and insulin-like growth factor-1) and vitamin D levels were measured. Descriptive statistics and logistic regression models were used to estimate the prevalence of sarcopenia and identify sarcopenia risk factors in patients with epilepsy.

RESULTS

This study enrolled 300 adults (mean age: 42.9 ± 14.7 years; women: 53.7 %). The epilepsy and control groups comprised 200 and 100 participants, respectively. The overall prevalence of sarcopenia was 31.3 % and it was significantly higher (p = 0.004) in women (20.7 %) than in men (10.6 %). The prevalence was higher in the epilepsy group than in the control group (36.0 % vs. 22.0 %, p = 0.014). Logistic regression revealed female, age (≥ 65 year) and low body mass index (BMI) were influenced the risk of sarcopenia in all participants. Importantly, epilepsy is significantly associated sarcopenia. The BMI, protein level, calf circumference, and use of enzyme-inducing antiseizure medications (EIASM) influenced the risk of sarcopenia in the epilepsy group.

CONCLUSION

The prevalence of sarcopenia is significantly higher in patients with epilepsy than in the control participants. Low BMI, protein level, calf circumference, and the use of EIASM may increase the risk of sarcopenia in this population. Our findings underscore the need for mitigating sarcopenia risk in patients with epilepsy.

Muscle Mass as a Biomarker for Health Status and Function in Pediatric Individuals with Neuromuscular Disabilities: A Systematic Review

This systematic review aims to investigate the relationship between muscle mass and specific health outcomes in pediatric populations with neuromuscular disorders. A search was performed for any relevant studies published in English from 1996 to 2023 in five databases. To be included in this analysis, articles must have had participants with an average age ≤21, focus on children with neuromuscular disabilities, and primarily examine relationships between muscle mass and any functional or health outcomes measure. Studies including typically developing children were used to contrast and enhance findings. Thirty-two studies were included, with 10,129 unique individuals represented: seventeen studies focused on healthy/typically developing children; seven on children with cerebral palsy; three on children with Duchenne muscular dystrophy; two on children with sarcopenia; and one study each on children with osteoporosis, congenital muscular dystrophy, and other various neurologic disorders. Thirteen studies assessed functional outcomes, ten assessed bone outcomes, and nine assessed other cardiovascular/metabolic outcomes. All of the included studies demonstrated relationships between muscle mass and respective outcomes in varying measures. The results of this review demonstrate that there is a consistently recognized relationship between muscle mass and important health outcomes in children, supporting clinically targeting muscle mass as a means to optimize desired outcomes.

Comparison of elasticity changes in the paraspinal muscles of adolescent patients with scoliosis treated with surgery and bracing

Scoliosis is a three-dimensional spinal deformity, and paraspinal muscles play an important role as stabilizers of the spinal curve. In this prospective study, we compared elasticity changes in the paraspinal muscles of adolescent patients with scoliosis after surgery or bracing. Elasticity was measured on the concave and convex sides of the paraspinal muscles at the apex of the curve at the beginning of treatment and 6 and 12 months after treatment. Twenty-six patients with correction surgery (n = 15) or bracing (n = 11) were included. At initial evaluation, the Cobb angle was larger in the surgery group (72.3 ± 20.2° in surgery vs. 30.6 ± 5.1° in brace, p < 0.001). The estimated mean elasticity value of the paraspinal muscles was lower in the surgery group at baseline on the convex side (15.8 vs. 22.8 kPa, p = 0.037) and 6 months on both the concave (12.1 vs. 22.7 kPa, p = 0.004) and convex (13.4 vs. 23.8 kPa, p = 0.005) sides. There was a significant stiffness decrease from baseline to 6 months on the concave side in the surgery group (5.9 kPa, p = 0.025). However, the elasticity change recovered at 12 months without significant differences between the two groups.