Loss of appendicular muscle mass and loss of muscle strength in young postmenopausal women.

BACKGROUND: Different factors may predict loss of appendicular muscle mass (LossAMM) and loss of muscle strength (LossMS). We investigated the relationship between LossAMM or LossMS and baseline anthropometric measures, lifestyle habits, hormones, lipid profiles, and inflammatory markers in 49 healthy postmenopausal women (54.1 +/- 4.3 years) in a 24-36-month prospective study. METHODS: We measured parameters of lifestyle habits, anthropometry, lipid profiles, and blood levels of testosterone, estrone, estradiol, cortisol, dihydroepiandrostenedione, luteinizing hormone, intact parathyroid hormone (iPTH), 25-hydroxyvitamin D, thyroxine, leptin, adiponectin, C-reactive protein (CRP), and interleukin-6 and interleukin-2 receptors. Percentage of loss per year of isometric knee extensor strength defined LossMS, and percentage of loss of AMM per year (dual x-ray absorptiometry) defined LossAMM. RESULTS: The means (standard deviation) for LossMS and LossAMM were 1.17%/y (2.03) and 0.60%/y (0.74) and did not correlate (r = -0.001; p =.99). LossMS correlated negatively with level of physical activity (r = -0.28), femoral BMD (r = -0.30), alcohol consumption (r = -0.30), and luteinizing hormone (r = -0.32) and positively with estrone (r = 0.29) and iPTH (r = 0.32) (each at p <.05). LossAMM correlated negatively with AMM (r = -0.41; p <.01). Stepwise regression analyses showed that LossMS was significantly predicted by baseline physical activity (beta = -0.39) with an explanation of variation of the model (R(2)) of 6%, body mass index (BMI) (-0.40; 3%), high-density lipoprotein cholesterol (-0.29; 3%), estrone (0.32; 6%), iPTH (0.27; 7%), and interleukin-2 receptor (0.32; 5%). LossAMM was predicted by baseline height (0.56; 47%), body mass index (1.04; 83%), AMM (-0.92; 76%), thyroxine (-0.33; 8%), estrone (-0.61; 30%), and dihydroepiandrostenedione (0.44; 28%). CONCLUSIONS: LossMS and LossAMM in young postmenopausal women were not correlated with one another, and were determined by different factors.

Leptin and adiponectin levels in middle-aged postmenopausal women: associations with lifestyle habits, hormones, and inflammatory markers--a cross-sectional study.

To investigate the relationships between blood levels of leptin or adiponectin and lifestyle habits, hormones, and inflammatory markers, we measured parameters of alcohol intake, smoking, physical activity, and blood levels of leptin, adiponectin, testosterone, estrone, estradiol, cortisol, dihydroepiandrostenedione, luteinizing hormone, thyroxin, C-reactive protein (CRP), and interleukin 6 and interleukin 2 receptor in 76 healthy middle-aged postmenopausal women. Anthropometric measures and body composition (evaluated by dual-energy x-ray absorptiometry) and lipid profiles were also assessed. By simple regression, leptin correlated positively with fat and lean masses, glucose, triglycerides, low-density lipoprotein cholesterol, and total cholesterol, and negatively with high-density lipoprotein cholesterol. Adioponectin correlated negatively with fat and lean masses and low-density lipoprotein cholesterol, and positively with high-density lipoprotein cholesterol. Leptin concentration was correlated inversely with adiponectin (r = -0.26, P < .05) and positively with CRP (r = 0.56, P < .01). Adiponectin concentration was negatively correlated with time since last alcoholic drink (r = -0.24, P < .05) and CRP (r = -0.27, P < .05) and positively with testosterone level (r = 0.23, P < .05). By multiple regression analysis, leptin concentration was predicted by age (P < .05), testosterone (P < .05), adiponectin (P < .05), CRP (P < .01), and interleukin 6 receptor (P < .01). Adiponectin concentration was predicted by the time since last alcoholic drink (P < .05), testosterone (P < .05), leptin (P < .05), and C-reactive protein (P = .05). Similar results were found when leptin or adiponectin concentration was adjusted for fat mass. These results suggested that levels of leptin and adiponectin in middle-aged postmenopausal women are partially determined by sexual hormones and inflammatory marker levels, and both predicted one another. Moreover, adiponectin level may be modulated by alcohol intake.

Reliability of the 400-m usual-pace walk test as an assessment of mobility limitation in older adults.

OBJECTIVES: To assess the test-retest reliability of the 400-m usual-pace walk test (400-MWT), and to determine whether the 4-m walk test predicts inability to walk 400 m. DESIGN: Observational. SETTING: Community, 20-m tract course. PARTICIPANTS: Sixty study participants (aged>or=65) were enrolled from the community and met the following eligibility criteria: self-reported difficulty in two or more of four functional domains (mobility and exercise tolerance, upper extremity function, basic self-care, higher functional tasks of independent living) and a score of 18 or higher on the Mini-Mental State Examination. METHODS: The 400-MWT and 4-m walk test were each repeated within 7 days. RESULTS: The mean age+/-standard deviation of the study population was 84.3+/-6.3; 88.3% were women. Nineteen participants (31.7%) failed both 400-MWTs, and 41 successfully completed both tests (kappa=1). Mean walking speed for the 4-m test was 0.87+/-0.18 m/s for those who completed the 400-MWT and 0.53+/-0.17 m/s for those who failed (P<.001). The Spearman correlation coefficient between 4-m and 400-m walking speeds was 0.93. The estimated area under the receiver operating characteristic curve between 4-m walking speed and the ability to perform the 400-MWT was 0.91. The 4-m gait speed averaged less than 0.6 m/s in 80% of subjects who failed the 400-MWT. CONCLUSION: The test-retest reliability for inability to complete the 400-MWT is high. Four-m walking speed is highly predictive of ability to perform the 400-MWT. These findings may prove useful to future clinical trials and observational studies that involve assessment of mobility limitations in older adults.

Adiponectin levels in obese and non-obese middle-aged African-American women.

CONTEXT: Adiponectin levels in African-Americans are poorly described. OBJECTIVE: To assess predictors of serum adiponectin levels in obese and non-obese middle-aged African-American women. METHODS: Serum adiponectin, testosterone (T), free androgen index (FAI), estradiol, dehydroepiandrosterone sulfate (DHEAS), leptin, sex hormone binding globulin (SHBG), triglycerides and C-reactive protein (CRP) were measured in 142 obese and 102 non-obese, community-dwelling, African-American women in St. Louis, Missouri. Medical history, physical activity, anthropometry, medications and body composition were assessed. RESULTS: Adiponectin and SHBG levels were lower and leptin and CRP were higher in obese compared to non-obese women (P's < 0.01). Overall, log adiponectin was positively associated with age (R = 0.13) and log SHBG (R = 0.29), and inversely associated with anthropometric measures (R's = -0.17 to -0.36), serum androgens (R's = -0.21 to -0.23), log estradiol (R = -0.21), log leptin (R = -0.15), log triglycerides (R = -0.33) and log CRP (R = -0.29). Overall, multivariate modelling significantly predicted 32% of variation in adiponectin level; the most significant factors were WHR (ß = -1.33), SHBG (ß = 0.23) and triglycerides (ß = -0.34). In non-obese women, the model predicted 27% of variation in adiponectin level; no individual factor was independently associated. In obese women, the model predicted 30% of variation in adiponectin level; the most significant factors were WHR (ß = -1.49), triglycerides (ß = -0.34) and history of stroke (ß = -0.71). CONCLUSIONS: Adiponectin level in African-American women is predicted by WHR, SHBG, and triglycerides; stroke history adds predictive value in obese women.