Appendicular skeletal muscle mass: A more sensitive biomarker of disease severity than BMI in adults with mitochondrial diseases

Abstract

The study aimed to evaluate the body composition of patients with mitochondrial diseases (MD) and correlate it with disease severity. Overall, 89 patients (age ≥ 18 years) with MD were recruited, includin g 49 with chronic progressive external ophthalmoplegia (CPEO) and 40 with mitochondrial encephalomyopathy with lactate acidosis and stroke-like episodes (MELAS). Body composition, including fat mass index (FMI), fat-free mass index (FFMI), skeletal muscle mass index (SMI), and appendicular skeletal muscle mass index (ASMI), were examined using multifrequency bioelectric impedance analysis. Clinical assessments, including muscle strength, usual gait speed, and disease severity determined by the Newcastle Mitochondrial Disease Adult Scale score (NMDAS), were performed. The comparisons between patients group and age- and gender-matched healthy controls, as well as the correlations between anthropometric measurements, body composition, and disease severity were analyzed. Height, weight, body mass index (BMI), FFMI, SMI, and ASMI were significantly lower in patients with MD than in healthy controls. Notably, low muscle mass was noted in 69.7% (62/89) of MD patients, with 22 patients also presenting with compromised physical performance as indicated by decreased gait speed, resulting in 24.7% satisfied the sarcopenia diagnostic criteria. Disease severity was more negatively correlated with ASMI than it was with height, weight, and BMI. Subgroup analysis showed that in the MELAS subgroup, disease severity was negatively correlated with height, weight, and ASMI; whereas in the CPEO subgroup, it was only negatively correlated with ASMI and SMI. Additionally, ASMI was positively associated with muscle strength. Altogether, compared with BMI, ASMI is a more sensitive biomarker predicting disease severity of MD, both in MELAS and CPEO patients.

Plasma CAF22 Levels as a Useful Predictor of Muscle Health in Patients with Chronic Obstructive Pulmonary Disease

“…Appendicular skeletal muscle mass (ASM) and fat mass were calculated with the bioelectrical impedance analysis scale (RENPHO, Dubai, UAE). ASM was divided by the square of height to get an appendicular skeletal muscle mass index (ASMI), as described elsewhere [ 21 ]. Five participants dropped out during the study due to exacerbation or death and were excluded from the final analysis.…”

Association of Body Composition, Physical Functioning, and Protein Intake in Adult Patients With Mitochondrial Diseases

“…An increased muscle mass and strength may also be related to lower diabetes risk 17 . Altered body composition in MD patients has been reported, 9,12 and higher skeletal muscle mass index in these patients was correlated with higher muscle strength 12 . However, whether physical functioning is related to fat mass has not been established yet.…”

“…Poor physical functioning is predicted by a body weight that is either too low or too high, 4‐7 conditions that are frequently observed in MD patients 8‐12 . Also, body composition is known to be an important factor in physical functioning in the general population as well as in neuromuscular disorders in particular 6,7,13,14 .…”

Cognitive Profile of Patients With Mitochondrial Chronic Progressive External Ophthalmoplegia

“…All patients showed ragged red or blue fibers, and cytochrome oxidase deficiency fibers on muscle biopsies (18). The genetic test was performed following a standard protocol as previously reported (19)(20)(21). Twenty-four sporadic patients had single large-scale mitochondrial DNA deletions and four autosomal inherited patients had nuclear gene mutations, including ribonucleotide reductase M2B (two patients), DNA polymerase gamma (one patient), and thymidine kinase 2 (one patient).…”