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Body composition and weight gain are breast cancer risk factors that may influence prognosis. The Health, Eating, Activity, and Lifestyle Study was designed to evaluate the relations of body composition, weight history, hormones, and lifestyle factors to prognosis for women with breast cancer. In the cross-sectional analysis of this cohort study specific to 150 Hispanic and 466 non-Hispanic White women in New Mexico diagnosed between 1996 and 1999, the authors hypothesized that obesity measures are associated with baseline prognostic markers and that these associations are modified by ethnicity. Ethnic-stratified multiple logistic regression analyses showed divergent results for a tumor size of 1.0 cm or more and, to a lesser extent, positive lymph node status. Among Hispanics, the highest quartile for body mass index (29.5 vs. <22.5 kg/m2: odds ratio (OR) = 0.16, 95% confidence interval (CI): 0.03, 0.84) and for waist circumference (> or =95.0 vs. <78.5 cm: OR = 0.09, 95% CI: 0.01, 0.78) was significantly associated with a reduced tumor size. In contrast, for overweight and obese non-Hispanic White women, there was an increased association with obesity-related measures, particularly striking for the highest quartile of waist circumference (OR = 2.76, 95% CI: 1.45, 5.26). These findings suggest that Hispanics may have a different breast cancer phenotype than non-Hispanic Whites, which associates differently with body composition and weight history.

The purpose of this study was to determine skeletal muscle cutpoints for identifying elevated physical disability risk in older adults. Subjects included 4,449 older (> or = 60 years) participants from the Third National Health and Nutrition Examination Survey during 1988-1994. Physical disability was assessed by questionnaire, and bioimpedance was used to estimate skeletal muscle, which was normalized for height. Receiver operating characteristics were used to develop the skeletal muscle cutpoints associated with a high likelihood of physical disability. Odds for physical disability were compared in subjects whose measures fell above and below these cutpoints. Skeletal muscle cutpoints of 5.76-6.75 and < or =5.75 kg/m2 were selected to denote moderate and high physical disability risk in women. The corresponding values in men were 8.51-10.75 and < or =8.50 kg/m2. Compared with women with low-risk skeletal muscle values, women with moderate- and high-risk skeletal muscle values had odds for physical disability of 1.41 (95% confidence interval (CI): 0.97, 2.04) and 3.31 (95% CI: 1.91, 5.73), respectively. The corresponding odds in men were 3.65 (95% CI: 1.92, 6.94) and 4.71 (95% CI: 2.28, 9.74). This study presents skeletal muscle cutpoints for physical disability risk in older adults. Future applications of these cutpoints include the comparison of morbidity risk in older persons with normal muscle mass and those with sarcopenia, the determination and comparison of sarcopenia prevalences, and the estimation of health-care costs attributable to sarcopenia.

Aging is often accompanied by learning and memory problems, many of which resemble deficits associated with hippocampal damage. Studies of aging in nonhuman animals have demonstrated hippocampus-related memory decline, and point to a possible locus for impairments associated with normal and pathological aging in humans. Two well-characterized hippocampus-dependent tasks in nonhuman animal literature are the Morris water task (MWT) and the transverse patterning discrimination task (TPDT). We employed the virtual MWT and the TPDT to assess hippocampus-dependent cognition in humans. Magnetic resonance imaging and proton magnetic resonance spectroscopy were employed to measure hippocampal volume and neurochemistry respectively. Age-related deficits were observed in performance on both hippocampus-dependent tasks. This pattern of impairment was accompanied by decreased hippocampal NAA/Cre ratios and volume, both of which imply neuronal loss and/or decrease in neuronal density. Collectively, our results suggest that hippocampus undergoes structural and biochemical changes with normal aging and that these changes may represent an important component of age-related deterioration in hippocampus-dependent cognition.

Amenorrheic athletes exhibit a spectrum of neuroendocrine disturbances, including alterations in the GH-insulin-like growth factor I (IGF-I) axis. Whether these changes are due to exercise or amenorrhea is incompletely characterized. The present study investigates spontaneous (overnight) and exercise-stimulated GH secretion and associated IGF-binding proteins (IGFBPs) in amenorrheic (AA; n = 5), and eumenorrheic athletes ( n = 5) matched for age, percent body fat (dual energy x-ray absorptiometry), training history, and maximal oxygen consumption. Each volunteer participated in two hospital admissions consisting of a 50-min submaximal exercise bout (70% maximal oxygen consumption) and an 8-h nocturnal sampling period. Deconvolution analysis of serum GH concentration time series revealed increases in the half-life of GH (60%) and the number of secretory bursts (85%) as well as a decrease in their half-duration (50%) and the mass of GH secreted per pulse (300%) in the AA cohort. Time occupancy at elevated trough GH concentrations was significantly increased, and GH pulsatility (approximate entropy) was more irregular in the AA group. During exercise, AA exhibited a reversal of the normal relationship between IGF-I and GH, and a 4- to 5-fold blunting of stimulated peak and integrated GH secretion. Fasting levels of plasma IGF-I, IGFBP-3, and IGFBP-1 appeared to be unaffected by menstrual status. In ensemble, this phenotype of GH release in amenorrheic athletes suggests disrupted neuroregulation of episodic GH secretion, possibly reflecting decreased somatostinergic inhibition basally, and reduced GHRH output in response to exercise compared with eumenorrheic athletes. Accordingly, we postulate that the amenorrheic state, beyond the exercise experience per se, alters the neuroendocrine control of GH output in amenorrheic athletes.

Background: Pharmacogenomics, the study of genetic loci that modulate drug responsiveness, may help to explain why estrogen replacement therapy (ERT) has differential effects on serum lipid and lipoprotein concentrations in postmenopausal women who inherit distinct alleles of the apolipoprotein E gene (APOE)., Methods: We compared total-cholesterol, triglyceride, and lipoprotein (LDL and HDL) concentrations in 66 postmenopausal women receiving ERT ([+]ERT) with 174 postmenopausal women not receiving ERT ([-]ERT), controlling for three APOE genotypes divided into three groups: E2 (epsilon2/epsilon3, n = 31), E3 (epsilon3/epsilon3, n = 160), and E4 (epsilon3/epsilon4 + epsilon4/epsilon4, n = 49)., Results: Mean total-cholesterol concentrations were lower in all three [+]ERT groups compared with their [-]ERT counterparts but were statistically significant only for women in group E4 (P = 0.014). The mean LDL-cholesterol concentrations were significantly lower in all three [+]ERT groups compared with their [-]ERT counterparts (P

Muscle mass decreases with age, leading to "sarcopenia," or low relative muscle mass, in elderly people. Sarcopenia is believed to be associated with metabolic, physiologic, and functional impairments and disability. Methods of estimating the prevalence of sarcopenia and its associated risks in elderly populations are lacking. Data from a population-based survey of 883 elderly Hispanic and non-Hispanic white men and women living in New Mexico (the New Mexico Elder Health Survey, 1993-1995) were analyzed to develop a method for estimating the prevalence of sarcopenia. An anthropometric equation for predicting appendicular skeletal muscle mass was developed from a random subsample (n = 199) of participants and was extended to the total sample. Sarcopenia was defined as appendicular skeletal muscle mass (kg)/height2 (m2) being less than two standard deviations below the mean of a young reference group. Prevalences increased from 13-24% in persons under 70 years of age to >50% in persons over 80 years of age, and were slightly greater in Hispanics than in non-Hispanic whites. Sarcopenia was significantly associated with self-reported physical disability in both men and women, independent of ethnicity, age, morbidity, obesity, income, and health behaviors. This study provides some of the first estimates of the extent of the public health problem posed by sarcopenia.

Objectives: To identify the characteristics of elderly persons who develop a fear of falling after experiencing a fall and to investigate the association of this fear with changes in health status over time., Design: A prospective study of falls over a 2-year period (1991-92). Falls were ascertained using bimonthly postcards plus telephone interview with a standardized (World Health Organisation) questionnaire for circumstances, fear of falling and consequences of each reported fall. Each participant underwent a physical exam and subjective health assessment each year form 1990 to 1993., Setting: New-Mexico Aging Process Study, USA., Subjects: 487 elderly subjects (> 60 years) living independently in the community., Main Outcome Measures: Fear of falling after experiencing a fall., Results: 70 (32%) of 219 subjects who experienced a fall during the 2 year study period reported a fear of falling. Women were more likely than men to report fear of falling (74% vs 26%). Fallers who were afraid of falling again had significantly ore balance (31.9% vs 12.8%) and gait disorders (31.9% vs 7.4%) at entry in the study in 1990. Among sex, age, mental status, balance and gait abnormalities, economic resource and physical health, logistic regression analysis show gait abnormalities and poor self-perception of physical health, cognitive status and economic resources to be significantly associated with fear of falling. Subjects who reported a fear of falling experienced a greater increase in balance (P = 0.08), gait (P < 0.01) and cognitive disorders (P = 0.09) over time, resulting in a decrease in mobility level., Conclusion: The study indicated that about one-third of elderly people develop a fear of falling after an incident fall and this issue should be specifically addressed in any rehabilitation programme.

As a part of the Fels Body Composition Study (an extension of the Fels Longitudinal Study in Yellow Springs, Ohio), the hypothesis was examined that a centripetal fat pattern, characterized by a greater proportion of trunkal than extremity adiposity, was associated independent of age and per cent body fat with levels of plasma lipids and lipoprotein cholesterols and blood pressures. A cross-sectional sample of 303 white men and women, 18 to 57 years of age, measured between September 1976 and August 1979, was selected without regard to diagnosis of hypertension, hyperlipidemia, or obesity. The degree of centripetal adipose tissue distribution was indexed by the logarithm of the ratio of the subscapular to lateral calf skinfold thicknesses. Per cent body fat was estimated by densitometry. In multiple regression equations controlling for age, age2, and per cent body fat, centripetal fat pattern had a small but significant positive association with systolic blood pressure in men (R2 = 0.02, p less than 0.05). In women, centripetal fat pattern had small but significant positive associations with plasma triglycerides (R2 = 0.05, p less than 0.005), and a significant negative association with plasma high density lipoprotein cholesterol (R2 = 0.08, p less than 0.0005) after effects due to age, age2, and per cent body fat had been removed. Centripetal fat patterns appear to be associated with an "atherogenic" lipid profile in women, but the association in men is confounded with effects due to age and total body adiposity.