Central obesity is associated with lower prevalence of sarcopenia in older women, but not in men: a cross-sectional study.

BACKGROUND: Obesity is a chronic disease that causes various medical health problems, increases morbidity, and reduces the quality of life. Obesity (especially central obesity) in older adults is expected to act with the development of sarcopenia. However, the relationship between obesity, central obesity, and sarcopenia remains controversial. This study aimed to investigate the impact of obesity on sarcopenia. METHODS: In this cross-sectional study, we used data from the Korean Frailty and Aging Cohort Study; 1,827 community-dwelling older adults (883 men and 944 women) aged 70-84 years were recruited. The Asian Working Group for Sarcopenia (AWGS) criteria were used to evaluate sarcopenia. Subjects with a low appendicular skeletal muscle mass index (ASMI; men: < 7.0 kg/m2, women: < 5.4 kg/m2) and either low handgrip strength (HGS; men: < 28 kg, women: < 18 kg) or low Short Physical Performance Battery (SPPB; ≤ 9) were diagnosed with sarcopenia. Obesity was defined as a body mass index (BMI) of ≥ 25 kg/m2, while central obesity was defined as WC measurements of ≥ 90 cm in men and ≥ 85 cm in women. Logistic regression analyses were performed to evaluate the impact of obesity and central obesity on sarcopenia and the parameters of sacropenia. RESULTS: In both sexes, the obese group, defined based on the BMI, had a significantly low prevalence of low ASMI (odds ratio [OR] = 0.14, 95% confidence interval CI = 0.10-0.20 in men, OR = 0.17, 95% CI = 0.12-0.25 in women) and sarcopenia (OR = 0.28, 95% CI = 0.16-0.50 in men, OR = 0.17, 95% CI = 0.08-0.35 in women) in the multivariable logistic regression analysis. In women, the central obese group had a low prevalence of sarcopenia (OR = 0.46, 95% CI = 0.27-0.77) in the multivariable logistic regression analysis. Meanwhile, the obese group had a significantly higher prevalence of low SPPB in women (OR = 1.75, 95% CI = 1.18-2.59). CONCLUSIONS: Obesity may have a protective effect on low ASMI and sarcopenia, as defined by the AWGS criteria. Central obesity was associated with a low prevalence of sarcopenia in women only. However, obesity did not have a positive impact on functional parameters of sarcopenia including muscle strength and physical performance.

Measuring the cumulative effect of G force on aviator neck pain.

INTRODUCTION: In many studies, high G force is thought to be the most important causal factor of aviator neck pain. However, most of the studies performed to date have compared neck pain of aviators exposed to high G force with that of aviators not so exposed or with that of the general population. As a result, neck pain for aviators exposed to high G force as it relates to G level is not yet well-known. METHODS: The subjects were 1003 male aviators who were sent an anonymous questionnaire. Subject variables were information on physical characteristics, lifestyle, and flight characteristics, including information about exposed maximum G (Gmax). There were three dependent variables: whether the aviator had experienced neck pain, frequency of neck pain, and subjective severity of neck pain. RESULT: With the multivariate analysis, amount of Gmax exposure (frequency or monthly duration of Gmax exposure) had a statistically significant positive relationship with all three dependent variable. BMI, flight hours in current aircraft, and posterior seat type had a meaningful positive relationship with experience of neck pain and subjective severity of neck pain. Other characteristics, including Gmax level, were not significantly related with any dependent variables. DISCUSSION: These results suggest that G level could have a ceiling effect; in other words, above a certain G level, aviator neck pain risk does not increase. This means that amount of Gmax exposure becomes more influential on aviator neck pain than the level of Gmax.

Association of Lumbar Paraspinal Muscle Morphometry with Degenerative Spondylolisthesis.

The objective of this study was to assess the cross-sectional areas (CSA) of lumbar paraspinal muscles and their fatty degeneration in adults with degenerative lumbar spondylolisthesis (DLS) diagnosed with chronic radiculopathy, compare them with those of the same age- and sex-related groups with radiculopathy, and evaluate their correlations and the changes observed on magnetic resonance imaging (MRI). This retrospective study included 62 female patients aged 65-85 years, who were diagnosed with lumbar polyradiculopathy. The patients were divided into two groups: 30 patients with spondylolisthesis and 32 patients without spondylolisthesis. We calculated the CSA and fatty degeneration of the erector spinae (ES) and multifidus (MF) on axial T2-weighted magnetic resonance (MR) images from the inferior end plate of the L4 vertebral body levels. The functional CSA (FCSA): CSA ratio, skeletal muscle index (SMI), and MF CSA: ES CSA ratio were calculated and compared between the two groups using an independent t-test. We performed logistic regression analysis using spondylolisthesis as the dependent variable and SMI, FCSA, rFCSA, fat infiltration rate as independent variables. The result showed more fat infiltration of MF in patients with DLS (56.33 vs. 44.66%; p = 0.001). The mean FCSA (783.33 vs. 666.22 mm2; p = 0.028) of ES muscle was a statistically larger in the patients with DLS. The ES FCSA / total CSA was an independent predictor of lumbar spondylolisthesis (odd ratio =1.092, p = 0.016), while the MF FCSA / total CSA was an independent protective factor (odd ratio =0.898, p = 0.002).