Park CH, et al. Ann Rehabil Med. 2017 Oct;41(5):776-785. https://doi.org/10.5535/arm.2017.41.5.776

Background: Homocysteine has been drawing attention with a closed linkage with skeletal muscle. However, the association of hyperhomocysteinemia with decreased skeletal muscle mass remains unclear. We aimed to investigate the association of hyperhomocysteinemia with low skeletal muscle mass (LMM) in asymptomatic adults.Methods: This was a cross-sectional study of 114,583 community-dwelling adults without cancer, stroke, or cardiovascular diseases who underwent measurements of plasma homocysteine and body composition analysis from 2012 to 2018. Hyperhomocysteinemia was defined as >15 μmol/L. Skeletal muscle mass index (SMI) was calculated based on appendicular muscle mass (kg)/height (m)2. Participants were classified into three groups based on SMI: “normal,” “mildly low,” and “severely low.”Results: The prevalence of hyperhomocysteinemia was the highest in subjects with severely LMM (12.9%), followed by those with mildly LMM (9.8%), and those with normal muscle mass (8.5%) (P for trend <0.001). In a multivariable logistic regression model, hyperhomocysteinemia was significantly associated with having a mildly LMM (odds ratio [OR], 1.305; 95% confidence interval [CI], 1.224 to 1.392) and severely LMM (OR, 1.958; 95% CI, 1.667 to 2.286), respectively. One unit increment of log-transformed homocysteine was associated with 1.360 and 2.169 times higher risk of having mildly LMM and severely LMM, respectively.Conclusion: We demonstrated that elevated homocysteine has an independent association with LMM in asymptomatic adults, supporting that hyperhomocysteinemia itself can be a risk for decline in skeletal musculature.

We investigated the sex-specific association between ferritin and adverse body composition in adults aged over 50 years in a population-based cohort. A total of 25,546 participants (16,912 women; 8634 men) were stratified into three groups by the tertiles of ferritin. The number of adverse body compositions was categorized as 0 (without osteopenia/osteoporosis, low muscle mass, or obesity), 1 (having one of the components), 2 (two), and 3 (all three; osteosarcopenic obesity). As ferritin tertile increased, the prevalence of one, two, or three simultaneous adverse body compositions increased, significant only in women (p < 0.0001), not in men (p = 0.125). Among women, the prevalence of osteosarcopenic obesity gradually increased from 1.7% in the lowest, to 2.2% in the middle, and 2.5% in the highest tertile. Using multivariate-adjusted analysis, women in the higher tertile had an increased likelihood of having multiple adverse body compositions compared with those in the lowest tertile. Women in the highest tertile had a 1.52 times increased risk of osteosarcopenic obesity than those in the lowest tertile. A high ferritin level was associated with an increased risk of having multiple adverse body compositions, especially for osteosarcopenic obesity in women aged >50 years, suggesting its potential use for detecting osteosarcopenic obesity.

The relationship between hyperhomocysteinemia (HHcy) and obesity with low skeletal muscle mass (LMM) has not been established. We aim to assess the association between HHcy and the coexistence of obesity and LMM in asymptomatic adult population. We conducted a population-based cross-sectional study among asymptomatic individuals who underwent measurements of plasma homocysteine and body composition analysis. HHcy was defined as > 15 umol/L, obesity as body mass index ≥ 25 (kg/m²), and LMM as skeletal muscle index less than 2 SD below the sex-specific mean of young adults. The participants were classified into ‘control’, ‘obesity alone’, ‘LMM alone’, and ‘obesity with LMM’. Among 113,805 participants, the prevalence of HHcy was 8.3% in control, 8.7% in obesity alone, 10.0% in LMM alone, and 13.0% in obesity with LMM (p for trend < 0.001). In a multivariable logistic regression analysis, the associations showed a positive trend for HHcy along the groups from obesity alone, to LMM alone, and to obesity with LMM. HHcy was independently associated with the presence of LMM alone (adjusted odds ratio 1.186 [95% confidence interval 1.117–1.259]) and obesity with LMM (1.424 [1.134–1.788]), respectively. This study demonstrated that HHcys was more strongly associated with coexistence of obesity and LMM than either condition alone in the adult population.

Background and Objectives: The study aimed to establish the threshold values and prevalence of sarcopenia and to investigate the association of sarcopenia with metabolic syndrome in an urban Korean population. Materials and Methods: The study included 300,090 adults who underwent anthropometric analyses by bioelectrical impedance analyzer. Sarcopenia was defined as: (1) class I, skeletal muscle mass index (SMI) within −1 to −2 standard deviations (SDs); (2) or class II, <−2 SD of SMI in a young population. Results: Low SMI threshold levels for class I and class II sarcopenia were 39.8 and 36.7% in men, and 35.5 and 32.3% in women. Among all age groups, the prevalence rates of sarcopenia were highest in the age group 80–89 years. Following adjustment for possible confounders including age, sex, height, metabolic and health behavioral factors, adjusted odds ratios (95% confidence intervals) for the risk of metabolic syndrome were 2.43 (2.33–2.54) for class I and 2.69 (2.49–2.91) for class II sarcopenia, compared with the normal reference. Sarcopenia was more strongly associated with metabolic syndrome in women than men (p for interaction < 0.01). The threshold values and prevalence of sarcopenia were demonstrated in a large Korean urban population. Conclusions: This study identified that sarcopenia was associated with increased risk of metabolic syndrome, showing itself to be significantly higher in women than men.

Lee JY, et al. Ann Rehabil Med. 2017 Feb;41(1):42-50. https://doi.org/10.5535/arm.2017.41.1.42