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1.
Maximal power in sustained work in originally randomly selected men and women, born in 1914, was studied five times between the ages of 50 and 80 years in a longitudinal design. Of the originally 514 men and 461 women in 1964 living in the Western suburbs of Copenhagen, 23 men and 18 women performed a bicycle test at age 50, 60, 70, 75 and 80. The mean annual decline in body mass adjusted maximal power in sustained work (W/kg) was 1.43% in the 18 men and 1.64% in the 23 women. Based on "cross-sectional" comparisons of all subjects tested at any age, the mean annual decline in men was 1.56%; in women the corresponding figure was 1.80%. When the results of the "longitudinal" and "cross-sectional" analyses were compared with each other, a rather similar picture of the age-related decline in maximal power was obtained, especially in women. In the longitudinal data only moderate (women) or zero (men) correlations were observed between the submaximal test results at the ages of 50 and 60 years and the maximal test results at higher ages. The physical work load at the age of 50 years had no significant correlation with maximal power at that age or thereafter. There were only minor changes in mean body height, body mass and BMI during the follow-up.  相似文献   

2.
OBJECTIVE: Osteoarthritis (OA) is associated with an increase in bone density both locally and at distant sites. Prospective data are limited on the relationship between OA and fracture. We studied the possible relationship between self-reported OA, bone density, postural stability measures, and atraumatic fractures as part of a study of men and women over 60 years of age. METHODS: Subjects were part of the Dubbo Osteoporosis Epidemiology Study (a longitudinal population based study of fracture risk factors). Bone density was measured by dual energy x-ray absorptiometry. Postural stability was assessed by the validated measures of quadriceps strength and sway. Medication use and self-reported arthritis were assessed by a structured personal interview. Fractures were ascertained retrospectively by interview and prospectively by viewing radiographic reports for fracture. RESULTS: Among a study population of 1101 women and 720 men (mean age 69) there were 462 subjects (25%) who reported a diagnosis of OA. In both sexes, subjects with OA had higher bone density (adjusted for age and body mass index) at both the femoral neck (men, p = 0.026; women, p = 0.048) and lumbar spine (men, p = 0.0007; women, p = 0.0007). However, in both sexes, those with self-reported OA also had higher body sway and lower quadriceps strength. The combination of these observed differences in fracture risk factors led to no predicted change in fracture risk overall when using established nomograms for this population [men, OR = 1.11 (95% CI 0.83-1.45); women, OR = 1.08 (95% CI 0.83-1.39)]. This paralleled our observational finding that self-reported OA was not associated with a decrease in fracture incidence compared to those not reporting OA in both men (RR 0.64, 95% CI 0.29-1.39) and women (RR 1.00, 95% CI 0.66-1.51). CONCLUSION: Individuals with self-reported OA, despite higher bone density, are not protected against nonvertebral osteoporotic fracture, apparently due to worsened postural stability and thus an increased tendency to fall.  相似文献   

3.
Status of risk factors for dementia associated with stroke   总被引:1,自引:0,他引:1  
This study presents a brief investigation into sex differences of speakers in the voice onset time of English plosives that are stressed in both word-initial and prevocalic position. 72 short phrases were presented to 5 men (range 25 to 37 years, mean age 34.2 yr.) and five women speakers (range 28 to 38 years, mean 32.6 yr.). Analysis showed that the women as speakers had on average, longer voice onset time values than their male peers.  相似文献   

4.
AIMS: Heart rate variability has been proposed as an indicator of cardiovascular health. Since women have a lower cardiovascular risk, we hypothesized that there are gender differences in autonomic modulation. METHODS AND RESULTS: In 276 healthy subjects (135 women, 141 men) between 18 and 71 years of age, 24 h heart rate and heart rate variability were determined. All heart rate variability parameters, except for pNN50 and high frequency power, were higher in men. After adjustment for heart rate, we obtained gender differences for: the standard deviation (P=0.049), the standard deviation of the 5 min average (P=0.047), low frequency power (absolute values, P=0.002; normalized units, P<0.001) and ratio low frequency/high frequency (P<0.001). There were no significant gender differences in heart rate variability parameters denoting vagal modulation. Gender differences were confined to age categories of less than 40 years of age. The majority of heart rate variability parameters decreased with age. Only in men, was a higher body mass index associated with a higher heart rate and with lower heart rate variability parameters (P<0.001). CONCLUSION: Cardiac autonomic modulation as determined by heart rate variability, is significantly lower in healthy women compared to healthy men. We hypothesize that this apparently paradoxical finding may be explained by lower sympathetic activity (low frequency power) in women. This may provide protection against arrhythmias and against the development of coronary heart disease.  相似文献   

5.
The impact of weight change in adulthood on cardiovascular disease is controversial. This study examined the association of change in body weight, from young adulthood to middle age, with average carotid artery intimal-medial wall thickness by B-mode ultrasound measured in middle age. Participants were 13,282 men and women aged 45-64 years from the baseline examination of the Atherosclerosis Risk in Communities (ARIC) Study (1987-1989). Weight change was calculated as the difference between weight at the baseline examination and self-reported weight at age 25. White men gained a mean of 9.7 kg; black men, 10.1 kg; white women, 12.0 kg; and black women, 20.8 kg. Weight change was positively, albeit modestly, associated with intimal-medial thickness in black men and white men and in white women, but not in black women. Adjusted for age, examination center, smoking, education, sports activity level, height, and body mass index at age 25, the differences in intimal-medial thickness associated with a 10-kg increment in weight change were 0.016 (95% confidence interval 0.010 to 0.022) mm in white men, 0.008 (95% confidence interval 0.001 to 0.015) mm in black men, 0.013 (95% confidence interval 0.009 to 0.017) mm in white women, and 0.002 (95% confidence interval -0.002 to 0.006) mm in black women. These findings support the hypothesis that weight gain in adulthood promotes atherosclerotic changes in white men and women and in black men.  相似文献   

6.
L. M. Giambra (1977–1978, 1979–1980) found that 2 scales of the Imaginal Processes Inventory measuring curiosity (i.e., information seeking) did not change across the adult life span, but 2 measuring stimulation seeking (i.e., boredom) for external stimulation need significantly decreased with age. In this study, these outcomes were replicated (1,356 men and 1,080 women [aged 17–92 yrs]). In addition, a 6- to 8-yr longitudinal repeat was obtained on 222 men and 124 women. Significant longitudinal declines were obtained for the stimulation-seeking measures. Furthermore, women showed an increase in impersonal–mechanical curiosity and a decline in interpersonal curiosity, though the amount of change was modest. Men were unchanged on both curiosity measures. Gender differences in longitudinal changes apparently reflected effects of socialization as well as tendencies toward displaying increased androgyny with advancing age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
To determine the effects of strength training (ST) on muscle quality (MQ, strength/muscle volume of the trained muscle group), 12 healthy older men (69 +/- 3 yr, range 65-75 yr) and 11 healthy older women (68 +/- 3 yr, range 65-73 yr) were studied before and after a unilateral leg ST program. After a warm-up set, four sets of heavy-resistance knee extensor ST exercise were performed 3 days/wk for 9 wk on the Keiser K-300 leg extension machine. The men exhibited greater absolute increases in the knee extension one-repetition maximum (1-RM) strength test (75 +/- 2 and 94 +/- 3 kg before and after training, respectively) and in quadriceps muscle volume measured by magnetic resonance imaging (1,753 +/- 44 and 1, 955 +/- 43 cm3) than the women (42 +/- 2 and 55 +/- 3 kg for the 1-RM test and 1,125 +/- 53 vs. 1,261 +/- 65 cm3 for quadriceps muscle volume before and after training, respectively, in women; both P < 0.05). However, percent increases were similar for men and women in the 1-RM test (27 and 29% for men and women, respectively), muscle volume (12% for both), and MQ (14 and 16% for men and women, respectively). Significant increases in MQ were observed in both groups in the trained leg (both P < 0.05) and in the 1-RM test for the untrained leg (both P < 0.05), but no significant differences were observed between groups, suggesting neuromuscular adaptations in both gender groups. Thus, although older men appear to have a greater capacity for absolute strength and muscle mass gains than older women in response to ST, the relative contribution of neuromuscular and hypertrophic factors to the increase in strength appears to be similar between genders.  相似文献   

8.
Considerable variation remains in the reported effects of disease, age and gender on high frequency electroencephalographic activity. We examined the topographic differences in relative and absolute beta power in the 14-54 Hz range in 49 subjects with dementia of the Alzheimer's type (DAT), 25 subjects with multi-infarct dementia (MID), and 62 normal control subjects (CON). Associations of these spectral parameters with age, gender and cognitive status were assessed. Normal control subjects showed modest positive correlations in frontal, central and parietal regions across the age range of 24-90 years but not across a narrower 60-90 year range. Women, particularly women over 60 years of age, showed increased relative and absolute beta power compared to men. Subjects with dementia showed global decreases particularly in relative power. Decreases were most prominent in central and parietal regions for DAT subjects, with MID subjects additionally showing prominent frontal decreases. DAT and MID subjects differed in their correlations of power with age, Folstein Mini Mental State Exam (MMSE) and gender across frontal, central, parietal and temporal regions. Differences in the regional attenuation of absolute and relative beta power within specific high frequency bands may reflect the disparate neuropathologic processes of DAT and MID, as well as the extent of brain dysfunction and the effects of gender.  相似文献   

9.
A sample of 558 women and 1,163 men 17 to 102 years old, screened for neurodegenerative and neuropsychiatric disease, was administered tests of immediate visual memory (Benton Visual Retention Test) and crystallized intelligence (Wechsler Adult Intelligence Scale Vocabulary subtest) from 1 to 5 times over 27.7 years. Cross-sectional and longitudinal evidence led to the conclusion that the 65-74-year decade was a watershed for decremental changes in immediate visual memory and verbal intelligence. Age accounted for considerably less variance in vocabulary than in immediate memory. The proportion of individuals whose longitudinal trajectories were contrary to group trends decreased substantially with increased age; observed age changes remained when analyses were restricted to individuals who had perfect or near-perfect mental status scores. Selected neuronal loss and slower reproduction times were considered as possible causes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

10.
PURPOSE: The aim of this study was to evaluate sonographically measured absolute and relative lengths of normal kidneys according to subject height, sex, and age. METHODS: Real-time sonography was performed on 202 subjects. Measurements of longitudinal renal diameter represented absolute renal length. Relative renal length was calculated using the kidney length: body height ratio (KBR). RESULTS: Statistical analyses were done on findings in 175 subjects without renal impairment (104 men and 71 women) whose ages ranged from 17 to 85 years (mean +/- SD, 46.3 +/- 17.1). The mean heights of the subjects were 176 +/- 7 cm for men and 167 +/- 6 cm for women. The left kidney was absolutely (mean +/-SD, 112 +/- 9 mm) and relatively (mean KBR +/- SD, 0.655 +/- 0.042) longer than the right kidney (absolute length, 110 +/- 8 mm; KBR, 0.641 +/- 0.038), regardless of sex (p < 0.01). The absolute renal length was significantly greater in men than in women for both kidneys (p < 0.01), but there was no significant difference between KBRs (p > 0.05). Renal length decreased with age, and the rate of decrease seemed to accelerate at 60 years and older. When height and age were included in the multivariate regression analysis, sex was not a significant predictor of kidney length. CONCLUSIONS: Relative renal length better represents kidney size than absolute renal length because it eliminates sex and height differences.  相似文献   

11.
In cognitive aging research, the study of a general cognitive factor has been shown to have a substantial explanatory power over the study of isolated tests. The authors aimed at differentiating the impact of gender and education on global cognitive change with age from their differential impact on 4 psychometric tests using a new latent process approach, which intermediates between a single-factor longitudinal model for sum scores and an item-response theory approach for longitudinal data. The analysis was conducted on a sample of 2,228 subjects from PAQUID, a population-based cohort of older adults followed for 13 years with repeated measures of cognition. Adjusted for vascular factors, the analysis confirmed that women performed better in tests involving verbal components, while men performed better in tests involving visuospatial skills. In addition, the model suggested that women had a slightly steeper global cognitive decline with oldest age than men, even after excluding incident dementia or death. Subjects with higher education exhibited a better mean score for the 4 tests, but this difference tended to attenuate with age for tests involving a speed component. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
A cross-sectional sample of men (n?=?177) tested in 1962–1964, and men (n?=?188) and women (n?=?113) tested in 1980–1984, and a longitudinal sample (n?=?53) of men tested in 1962–1964 and 1980–1984, were used to investigate age differences and 18-year age changes on a 62-min sensory vigilance task that made virtually no demand on memory, the Mackworth Clock-Test. Age differences and changes in the vigilance decrement were also examined. No age differences or changes were obtained for detection accuracy. Target response time showed significant age-related 18-year longitudinal changes and one significant cross-sectional age difference; the overall age effect was of a U-shaped function with a minimum at middle age. Age differences and changes were obtained in a measure of arousal: skin potential response latency; the overall age effect was also consistent with a U-shaped function. There was little consistent evidence of a differential effect of age on the vigilance decrement. Outcomes contradictory to Surwillo and Quilter (1964) and Quilter, Giambra, and Benson (1983) are reconciled through additional statistical analyses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
We studied physical fitness and physical activity in relation to all-cause and cancer mortality in a cohort of 7080 women and 25,341 men examined at the Cooper Clinic in Dallas, Texas, during 1970 to 1989. Physical fitness was assessed at baseline by a maximal treadmill exercise test, while physical activity was self-reported on the attendant health habits questionnaire. Both men and women averaged about 43 years of age at baseline (range, 20 to 88 years), and they were followed for approximately 8 years on average. Through the end of 1989, the women contributed 52,982 person-years of observation and incurred 89 deaths, including 44 deaths due to cancer. The men contributed 211,996 person-years and incurred 601 deaths, with 179 due to cancer. After adjustment for baseline differences in age, examination year, cigarette habit, chronic illnesses, and electrocardiogram abnormalities, we found a strong inverse association between risk of all-cause mortality and level of physical fitness in both men and women (P for trend < 0.001). Physically active men also were at lower risk of all-cause mortality than were sedentary ones (P for trend = 0.01). Among women, however, self-reported physical activity was not significantly related to risk of death from all causes. The risk of mortality from cancer declined sharply across increasing levels of fitness among men (P for trend < 0.001), whereas among women the gradient was suggestive but not significant (P for trend = 0.07). Physically active men also were at lower risk of death from cancer than were sedentary men (P for trend = 0.002), but among women physical activity was unrelated to cancer mortality.  相似文献   

14.
We used a life span sample of 18- to 91-year-old men (n?=?176) and women (n?=?108) to investigate sex differences and the effect of age on sex differences in performance and arousal during a 62-min no-memory-demand sensory vigilance task (Mackworth's Clock-Test). We observed sex differences in target response time and on measures of autonomic arousal; women were slower and less aroused than men. A review of the literature, in conjunction with the results of this study, led to our concluding that women are slower to respond to targets than men and that women may tend to detect fewer targets than men only when they are young (18–29 years old). Sex differences in arousal levels were consistent with an arousal explanation of sex differences in response time. However, detection accuracy and false alarm rates were not consistent with sex differences in arousal levels. Sex differences in the time course of vigilance performance were inconsistent. Age did not significantly moderate the sex differences in vigilance decrement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
We used bone ultrasound technology with its measurement of attenuation (broadband ultrasound attenuation [BUA] as dB/MHz) and sound velocity (speed of sound as m/s) for assessing the quantitative ultrasound index (QUI) summary measure in a triethnic population of 280 pregnant women. The study purpose was to describe the reproducibility of the ultrasound technology and determine if the correlations of age, weight, and ethnicity with the bone status measures in this population are consistent with the correlations of age, weight, and ethnicity that have been reported with other technologies that measure bone mass. We evaluated the first 280 women enrolled in our longitudinal study of lead turnover from maternal bone during pregnancy and lactation. Enrollees were pregnant, aged 12-29 years, and self-classified as black, white, or Hispanic. Bone ultrasound was measured twice at entry to prenatal care, which, on average, was at 14 weeks gestation. Reproducibility was described with intraclass correlations and the standard error of measurement. Age, weight, and ethnicity were associated with bone status measures using Spearman correlations and generalized linear models. The reproducibility of the summary bone measure, QUI, was high (96-97%). Variation in age and ethnicity did not alter reproducibility; however, the reproducibility of the attenuation measure (BUA as dB/MHz) lessened with increasing weight, declining from 95% to 89%. Since this attenuation is included in the summary QUI measure, there was a slight, and nonsignificant, decline in QUI reproducibility (from 97% to 96%) as women increased in size. There were no statistically significant differences in mean bone ultrasound measures according to age, where ages ranged from 12-29 years. Women who categorized themselves as black had, on average, an 8.5% greater QUI than did women who classified themselves as Hispanic or white. There were no significant pair-wise differences in mean ultrasound measures of bone between women classifying themselves as Hispanic or white. The use of ultrasound is a highly reproducible measure to assess bone characteristics in a population of pregnant adolescent and young adult women and its summary measure of bone mass is correlated with ethnic as well as body size characteristics.  相似文献   

16.
OBJECTIVE: To evaluate whether glycohemoglobin levels increase with age in both sexes and to determine the effect of BMI on this increment. RESEARCH DESIGN AND METHODS: A cross-sectional survey of 4,580 healthy Chinese men and women, aged 20-85 years, was performed. All subjects who did not have identifiable diseases and who were not on medication known to influence glucose tolerance were recruited from participants at the preventive services of the National Cheng-Kung University Hospital. As an indicator of plasma glucose levels, glycohemoglobin was measured. The subjects were classified according to their age and BMI for both men and women, and any relationships with glycohemoglobin levels were evaluated. RESULTS: In all the BMI groups divided into quartiles, glycohemoglobin levels increased with age. The largest elevation of glycohemoglobin was observed in the 45- to 54-year-old age-group, except in men with a BMI between the lowest and highest quartiles. The group with a BMI above the highest quartile had a higher glycohemoglobin than the group with a BMI below the lowest quartile in men aged < 54 years and women aged 35-64 years. Men had higher average glycohemoglobin levels than women < 55 years of age. CONCLUSIONS: The age factor itself may cause an elevation in glycohemoglobin independent of other age-related factors in Chinese men and women, and there is a sex difference with a lower average glycohemoglobin level in women before menopause. Furthermore, BMI, but not a family predisposition to diabetes or leisure-time physical activity, affects this age-dependent increase in glycohemoglobin levels.  相似文献   

17.
BACKGROUND: Osteoporosis is a substantial problem in older men, with 25% of all hip fractures occurring in men. The mechanisms of bone loss in older men are unknown, but elevated parathyroid hormone (PTH) and diminished testosterone (T) levels are postulated as contributing factors. METHODS: We measured bone mineral density (BMD), sex hormones, bone turnover markers, and calcium regulating hormones in a group of community-living men over the age of 75. RESULTS: Thirty-five men (mean age 79; range 75-88 years) without disease or medication known to affect bone metabolism participated in the study. Whole body BMD was 1.21+/-.15 g/cm2; lumbar spine BMD (L1-L4) was 1.10+/-.15 g/cm2; femoral neck BMD was .77+/-.14 g/cm2; and trochanteric region was .71+/-.13 g/cm2. The femoral neck and trochanteric region values were more than 1 SD below the mean for adult men (age 25-33 years) in 28/35 and 15/35 men, respectively. Deoxypyridinoline levels were above the normal range for premenopausal women in 23% of the men; N-telopeptide and C-telopeptide demonstrated a wide scatter, but the values remained in the normal range. T levels were found to be below normal range for adult men in 12 of 32 (38%) subjects and the PTH levels above the normal range in 8 of 35 (23%) subjects. Bone resorption markers correlated inversely with BMD of the whole body, femur, and spine (r=-.22 to -.48). There was an inverse correlation between total T and spine BMD which became insignificant after correcting for body mass index (BMI). In addition, there was no correlation between free or bioavailable testosterone and BMD. 1,25-(OH)2D levels correlated inversely with BMD at the femur and whole body, but no association was found with PTH or 25 OH-D. CONCLUSIONS: Men over 75 years of age had a wide range of BMD but frequently had low values at femoral sites. T levels were below the normal range in 38% of men, and PTH levels were elevated in 23% of men. There was an inverse correlation between total T and spine BMD which may have been dependent on the common effect of BMI. Bone mineral density was inversely related to markers of bone resorption.  相似文献   

18.
To understand better the role of endothelin-1 (ET-1) in the pathogenesis of primary Raynaud's phenomenon (PRP), we investigated the basal ET-1 plasma levels and changes after whole-body cooling in healthy women and those with PRP. The study was performed as an open parallel-group comparison during the month of February. The Raynaud group included 21 female patients (mean age 45.3 years, range 21-57 years) who had had disabling Raynaud's phenomenon for a mean period of 17 years (range 2-26 years). The control group consisted of 25 healthy women (mean age 43.6 years, range 27-56 years). Plasma levels of ET-1 were measured on two separate occasions: once after 30 min of rest at room temperature and after 40 min of whole-body cooling. There were no significant differences in baseline plasma ET-1 levels between the two groups of women. The plasma ET-1 levels increased significantly in the PRP group after cold exposure (mean difference 0.11 pmol l-1, 95% CI 0.005-0.214, P = 0.012). In contrast, the levels of plasma ET-1 in the control group did not change significantly after cold provocation. In conclusion, no differences in plasma basal levels of ET-1 were observed between the two groups. However, women suffering from Raynaud's phenomenon responded with a slight but significant elevation in plasma levels of ET-1 after whole-body cooling, whereas the healthy control subjects did not. The results from the present study confirm previous observations that endothelial dysfunction may be of aetiological importance in PRP.  相似文献   

19.
OBJECTIVES: To study carotid and femoral intima-media thicknesses and diameters in relation to age, sex, morphologic status and blood pressure. PARTICIPANTS: The subjects were 369 men and women (aged 10-54 years) from the Stanislas cohort, with no known cardiovascular disease. METHODS: Intima-media thicknesses and diameters were measured by B-mode ultrasonography. The effects of sex, age, smoking, anthropometric variables, cholesterol and blood pressure were studied using bivariate and regression analysis. RESULTS: Carotid and femoral intima-media thicknesses were not affected by age nor by sex up to 18 years of age. Thereafter, they increased sharply in men and remained higher than in women. Values were correlated with systolic blood pressure only in men, and with fat-free mass in children and young adults only at the femoral site. Smoking, body mass index and fat mass were associated with intima-media thicknesses only in adults. Carotid diameter was little affected by age during childhood and in adults. Femoral diameter increased up to the age of 18 in both sexes and remained unaffected by age thereafter. This increase was more pronounced in boys, and so values became consistently greater in males aged over 14 years. Carotid diameter was correlated with body mass index or fat mass whereas femoral diameter was correlated with weight or fat-free-mass in children and men. The opposite was observed in women. CONCLUSION: Sex differences occur before adolescence for arterial diameter, but only at an adult age for intima-media thickness. In young subjects, carotid geometry seems to be influenced by blood pressure and excess body weight, while femoral artery geometry seems to be related to blood pressure and body growth.  相似文献   

20.
Men (n = 31), women estrogen-users (n = 14), and women estrogen non-users (n = 41), whose average age was 72.1 +/- 5.6 years, were tested with a battery of psychological tests measuring verbal memory, visual memory, concentration and attention, language fluency and semantic memory, and mood. Plasma levels of testosterone (T), estradiol (E2), cortisol (CRT) and dehydroepiandrosterone-sulfate (DHEAS) were assessed by radioimmunoassay. The ratio of DHEAS to CRT was calculated to determine it's relationship to memory functioning. The men had higher T and DHEAS levels than both groups of women. Women estrogen-users had higher E2 levels than both men and estrogen non-users and the men had higher E2 levels and a higher DHEAS/CRT ratio than the estrogen non-users. There were no group differences in CRT levels. Men and estrogen-users had higher total (p < .01) and forward (p < .001) digit span scores compared with non-users. Women estrogen-users also had higher backward digit span scores than non-users (p < .05), while both groups of women performed better than men on category retrieval (p < .01). The implications of these findings with respect to hormonal influences on memory in elderly men and women are discussed.  相似文献   

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