Longitudinal studies on adipose tissue and its distribution in human subjects.

On 27 men and 6 women, total body density and 10 skinfolds were measured 12 yr apart, with the mean age increasing from 31 to 43 yr. The increase in skinfold thickness was found to be related to the increase in total body adiposity, calculated from hydrostatic weighing. The external adipose tissue was calculated from the mean skinfold thickness and body surface area. Variations in total adiposity among the population studied as well as changes in total adiposity with age showed a characteristic distribution with approximately two-thirds on the surface and one-third in the interior. The essential body mass or total adipose mass determined by hydrostatic weighing was compared with the values obtained by water-immersion volumetry, total body potassium counting, and skinfold measurements. Teh volumetric and skinfold determinations gave better estimates of these parameters than total body potassium counting.     

湖南土家族成人的皮褶厚度和体成分分析

本项目采用人体测量法,测量了976名(男性528人,女性448人)湖南土家族成人的身高、体质量以及肱三头肌、肩胛下、髂前上和小腿内侧皮褶的厚度,并根据公式计算体密度、体脂率、脂肪质量、脂肪质量指数、瘦体质量和瘦体质量指数。结果显示随年龄增长,小腿内侧皮褶厚度值逐渐减小,肱三头肌、肩胛下和髂前上棘皮褶以及体脂率、脂肪质量、瘦体质量、体质量指数、脂肪质量指数和瘦体质量指数值先增大后减小,体密度值先减小后增大;各年龄组中体密度、瘦体质量及其指数值女性明显低于男性,4项皮褶厚度值以及体脂率、脂肪质量及其指数值女性高于男性;与布朗族等24个族群比较,湖南土家族成人皮褶厚度处于中等水平,与门巴族、珞巴族、僜人、彝族等族群的亲缘关系较近。     

Cohort study of effect of being overweight and change in weight on risk of coronary heart disease in old age.

OBJECTIVE: To evaluate risk of late life coronary heart disease associated with being overweight in late middle or old age and to assess whether weight change modifies this risk. DESIGN: Longitudinal study of subjects in the epidemiological follow up study of the national health and nutrition examination survey I. SETTING: United States. SUBJECTS: 621 men and 960 women free of coronary heart disease in 1982-84 (mean age 77 years). MAIN OUTCOME MEASURE: Incidence of coronary heart disease. RESULTS: Body mass index of 27 or more in late middle age was associated with increased risk of coronary heart disease in late life (relative risk = 1.7 (95% confidence interval 1.3 to 2.1)) while body mass index of 27 or more in old age was not (1.1 (0.8 to 1.5)). This difference in risk was due largely to weight loss between middle and old age. Exclusion of those with weight loss of 10% or more increased risk associated with heavier weight in old age (1.4 (1.0 to 1.9)). Thinner older people who lost weight and heavier people who had gained weight showed increased risk of coronary heart disease compared with thinner people with stable weight. CONCLUSIONS: Heavier weight in late middle age was a risk factor for coronary heart disease in late life. Heavier weight in old age was associated with an increased risk once those with substantial weight loss were excluded. The contribution of weight to risk of coronary heart disease in older people may be underestimated if weight history is neglected.     

Impaired lung function and mortality risk in men and women: findings from the Renfrew and Paisley prospective population study.

OBJECTIVE: To assess the relation between forced expiratory volume in one second (FEV1) and subsequent mortality. DESIGN: Prospective general population study. SETTING: Renfrew and Paisley, Scotland. SUBJECTS: 7058 men and 8353 women aged 45-64 years at baseline screening in 1972-6. MAIN OUTCOME MEASURE: Mortality from all causes, ischaemic heart disease, cancer, hung and other cancers, stroke, respiratory disease, and other causes of death after 15 years of follow up. RESULTS: 2545 men and 1894 women died during the follow up period. Significant trends of increasing risk with diminishing FEV1 are apparent for both sexes for all the causes of death examined after adjustment for age, cigarette smoking, diastolic blood pressure, cholesterol concentration, body mass index, and social class. The relative hazard ratios for all cause mortality for subjects in the lowest fifth of the FEV1 distribution were 1.92 (95% confidence interval 1.68 to 2.20) for men and 1.89 (1.63 to 2.20) for women. Corresponding relative hazard ratios were 1.56 (1.26 to 1.92) and 1.88 (1.44 to 2.47) for ischaemic heart disease, 2.53 (1.69 to 3.79) and 4.37 (1.84 to 10.42) for lung cancer, and 1.66 (1.07 to 2.59) and 1.65 (1.09 to 2.49) for stroke. Reduced FEV1 was also associated with an increased risk for each cause of death examined except cancer for lifelong nonsmokers. CONCLUSIONS: Impaired lung function is a major clinical indicator of mortality risk in men and women for a wide range of diseases. The use of FEV1 as part of any health assessment of middle aged patients should be considered. Smokers with reduced FEV1 should form a priority group for targeted advice to stop smoking.     

Abdominal adipose tissue distribution,obesity, and risk of cardiovascular disease and death: 13 year follow up of participants in the study of men born in 1913.

In a prospective study of risk factors for ischaemic heart disease 792 54 year old men selected by year of birth (1913) and residence in Gothenburg agreed to attend for questioning and a battery of anthropometric and other measurements in 1967. Thirteen years later these baseline findings were reviewed in relation to the numbers of men who had subsequently suffered a stroke, ischaemic heart disease, or death from all causes. Neither quintiles nor deciles of initial indices of obesity (body mass index, sum of three skinfold thickness measurements, waist or hip circumference) showed a significant correlation with any of the three end points studied. Statistically significant associations were, however, found between the waist to hip circumference ratio and the occurrence of stroke (p = 0.002) and ischaemic heart disease (p = 0.04). When the confounding effect of body mass index or the sum of three skinfold thicknesses was accounted for the waist to hip circumference ratio was significantly associated with all three end points. This ratio, however, was not an independent long term predictor of these end points when smoking, systolic blood pressure, and serum cholesterol concentration were taken into account. These results indicate that in middle aged men the distribution of fat deposits may be a better predictor of cardiovascular disease and death than the degree of adiposity.     

Prospective study of risk factors for development of non-insulin dependent diabetes in middle aged British men.

OBJECTIVE--To determine the risk factors for noninsulin dependent diabetes in a cohort representative of middle aged British men. DESIGN--Prospective study. SUBJECTS AND SETTINGS--7735 men aged 40-59, drawn from one group practice in each of 24 towns in Britain. Known and probable cases of diabetes at screening (n = 158) were excluded. MAIN OUTCOME MEASURES--Non-insulin dependent diabetes (doctor diagnosed) over a mean follow up period of 12.8 years. RESULTS--There were 194 new cases of non-insulin dependent diabetes. Body mass index was the dominant risk factor for diabetes, with an age adjusted relative risk (upper fifth to lower fifth) of 11.6; 95% confidence interval 5.4 to 16.8. Men engaged in moderate levels of physical activity had a substantially reduced risk of diabetes, relative to the physically inactive men, after adjustment for age and body mass index (0.4; 0.2 to 0.7), an association which persisted in full multivariate analysis. A nonlinear relation between alcohol intake and diabetes was observed, with the lowest risk among moderate drinkers (16-42 units/week) relative to the baseline group of occasional drinkers (0.6; 0.4 to 1.0). Additional significant predictors of diabetes in multivariate analysis included serum triglyceride concentration, high density lipoprotein cholesterol concentration (inverse association), heart rate, uric acid concentration, and prevalent coronary heart disease. CONCLUSION--These findings emphasise the interrelations between risk factors for non-insulin dependent diabetes and coronary heart disease and the potential value of an integrated approach to the prevention of these conditions based on the prevention of obesity and the promotion of physical activity.     

Waist circumference action levels in the identification of cardiovascular risk factors: prevalence study in a random sample.

OBJECTIVE--To determine the frequency of cardiovascular risk factors in people categorised by previously defined "action levels" of waist circumference. DESIGN--Prevalence study in a random population sample. SETTING--Netherlands. SUBJECTS--2183 men and 2698 women aged 20-59 years selected at random from the civil registry of Amsterdam and Maastricht. MAIN OUTCOME MEASURES--Waist circumference, waist to hip ratio, body mass index (weight (kg)/height (m2)), total plasma cholesterol concentration, high density lipoprotein cholesterol concentration, blood pressure, age, and lifestyle. RESULTS--A waist circumference exceeding 94 cm in men and 80 cm in women correctly identified subjects with body mass index of > or = 25 and waist to hip ratios > or = 0.95 in men and > or = 0.80 in women with a sensitivity and specificity of > or = 96%. Men and women with at least one cardiovascular risk factor (total cholesterol > or = 6.5 mmol/l, high density lipoprotein cholesterol < or = 0.9 mmol/l, systolic blood pressure > or = 160 mm Hg, diastolic blood pressure > or = 95 mm Hg) were identified with sensitivities of 57% and 67% and specificities of 72% and 62% respectively. Compared with those with waist measurements below action levels, age and lifestyle adjusted odds ratios for having at least one risk factor were 2.2 (95% confidence interval 1.8 to 2.8) in men with a waist measurement of 94-102 cm and 1.6 (1.3 to 2.1) in women with a waist measurement of 80-88 cm. In men and women with larger waist measurements these age and lifestyle adjusted odds ratios were 4.6 (3.5 to 6.0) and 2.6 (2.0 to 3.2) respectively. CONCLUSIONS--Larger waist circumference identifies people at increased cardiovascular risks.     

Relationship between adiposity and body size reveals limitations of BMI

The aims of this study were to assess 1) whether the stature-adjusted body mass index (BMI) is a valid proxy for adiposity across both athletic and nonathletic populations, and 2) whether skinfold measurements increase in proportion to body size, thus obeying the principle of geometric similarity. The research design was cross-sectional, allowing the relationship between skinfold calliper readings (at eight sites and between specific athletic and nonathletic groups, n = 478) and body size (either mass, stature, or both) to be explored both collectively, using proportional allometric MANCOVA, and individually (for each site) with follow-up ANCOVAs. Skinfolds increase at a much greater rate relative to body mass than that assumed by geometric similarity, but taller subjects had less rather than more adiposity, calling into question the use of the traditional skinfold-stature adjustment, 170.18/stature. The best body-size index reflective of skinfold measurements was a stature-adjusted body mass index similar to the BMI. However, sporting differences in skinfold thickness persisted, having controlled for differences in body size (approximate BMI) and age, with male strength- and speed-trained athletes having significantly lower skinfolds (32% and 23%, respectively) compared with controls. Similarly, female strength athletes had 29% lower skinfold measurements compared to controls, having controlled for body size and age. These results cast serious doubts on the validity of BMI to represent adiposity accurately and its ability to differentiate between populations. These findings suggest a more valid (less biased) assessment of fatness will be obtained using surface anthropometry such as skinfolds taken by experienced practitioners following established procedures.     

Contribution of male sex, age, and obesity to mechanical instability of the upper airway during sleep.

Male sex, obesity, and age are risk factors for obstructive sleep apnea, although the mechanisms by which these factors increase sleep apnea susceptibility are not entirely understood. This study examined the interrelationships between sleep apnea risk factors, upper airway mechanics, and sleep apnea susceptibility. In 164 (86 men, 78 women) participants with and without sleep apnea, upper airway pressure-flow relationships were characterized to determine their mechanical properties [pharyngeal critical pressure under hypotonic conditions (passive Pcrit)] during non-rapid eye movement sleep. In multiple linear regression analyses, the effects of body mass index and age on passive Pcrit were determined in each sex. A subset of men and women matched by body mass index, age, and disease severity was used to determine the sex effect on passive Pcrit. The passive Pcrit was 1.9 cmH(2)O [95% confidence interval (CI): 0.1-3.6 cmH(2)O] lower in women than men after matching for body mass index, age, and disease severity. The relationship between passive Pcrit and sleep apnea status and severity was examined. Sleep apnea was largely absent in those individuals with a passive Pcrit less than -5 cmH(2)O and increased markedly in severity when passive Pcrit rose above -5 cmH(2)O. Passive Pcrit had a predictive power of 0.73 (95% CI: 0.65-0.82) in predicting sleep apnea status. Upper airway mechanics are differentially controlled by sex, obesity, and age, and partly mediate the relationship between these sleep apnea risk factors and obstructive sleep apnea.     

High prevalence of diabetes in an urban population in south India.

An urban population in a township in south India was screened for diabetes with an oral glucose tolerance test, every fifth person aged 20 and over registered at the local iron ore company''s hospital being screened. Of 678 people (346 men and 332 women) who were tested, 34 (5%; 20 men and 14 women) had diabetes and 14 (2%; 8 men and 7 women) had impaired glucose tolerance. Thirteen subjects were already known to be diabetic. Diabetes was present in 21% (37/179) of people aged over 40. The peak prevalence (41%; 7/17) was in the group aged 55-64. A family history of diabetes was present in 16 of the 34 subjects with diabetes and nine of the 15 with impaired glucose tolerance. Diabetes was significantly related to obesity in women but not in men (57% (8/14) v 5% (1/20)). The plasma glucose concentration two hours after glucose loading was correlated to body mass index, age, and income in both sexes. The prevalence of diabetes was significantly higher in subjects whose income was above the mean. When the overall prevalence of diabetes was adjusted to the age distribution of the Indians living in Southall, London, and in Fiji it increased to 10% and 9%, respectively. The prevalence of diabetes is high among urban Indians and is comparable with the high prevalence seen in migrant Indian populations.     

THE RELIABILITY OF SKINFOLD-CALIPERS FOR MEASURING BLUBBER THICKNESS OF STELLER SEA LION PUPS (EUMETOPIAS JUBATUS)

Twelve dead Steller sea lion pups ( Eumetopias jubatus ) aged 3-14 d were recovered from rookeries in Southeast Alaska. They had a wide range of body sizes and conditions (small to large and fat to no fat). The ability of calipers to estimate the thickness of their blubber layer was assessed with a set of skinfold calipers. Average error of measurement for skin and blubber thickness was an acceptable 5.4%, but the skin and blubber of the pups were highly compressible. Skinfold thickness increased with body mass but did not necessarily reflect the development of blubber, given that pups with no blubber also showed an increase in skinfold thickness with increases in body mass. Skinfold thickness of sea lion pups appears to predict body size better than it predicts blubber thickness, making it difficult if not impossible to develop a simple index of body condition or a calculation of percent body fat for Steller sea lion pups from skinfold caliper measurements.     

Stability of Adiposity Phenotypes from Childhood and Adolescence into Young Adulthood with Contribution of Parental Measures

Objective: The stability of several indicators of body composition and adipose tissue distribution over 12 years was quantified. Research Methods and Procedures: The participants were 77 boys and 76 girls who were evaluated along with their parents at baseline as children and adolescents (8 to 18 years of age) and remeasured as young adults 12 years later. Indicators of body composition included the body mass index, fat mass, fat free mass, percentage of body fat, sum of six skinfolds (SF6), and the first principal component of six age‐adjusted skinfold residuals. Relative adipose tissue distribution was represented by the second principal component of skinfold residuals and a trunk‐to‐extremity skinfold ratio, adjusted for SF6. Results: Partial interage correlations, controlling for initial age and length of follow‐up, were 0.65 and 0.59 for the body mass index, 0.59 and 0.64 for fat mass, 0.65 and 0.57 for fat free mass, 0.50 and 0.57 for percentage of body fat, 0.66 and 0.44 for SF6, 0.64 and 0.42 for the first principal component of six age‐adjusted skinfold residuals, 0.19 and 0.31 for the second principal component of skinfold residuals, and 0.41 and 0.47 for trunk‐to‐extremity skinfold ratio, adjusted for SF6, in men and women, respectively. Multiple regression analyses indicated that the significant partial R² values of parental measurements on the prediction of their offspring in young adulthood ranged from 2% to 9%. Discussion: The results indicate moderately high stability of indicators of body composition and somewhat lower stability of measures of adipose tissue distribution. Overall, parental measures offer less predictive value than do measures of childhood and adolescent body composition and adipose tissue distribution.     

Prevalence of coronary heart disease risk factors in a Cambridge, UK study

This paper examines the distribution and prevalence of risk factors for coronary heart disease in a sample of 165 men and 202 women over 40 years of age who had earlier participated in a coronary prevention trial from a general practice in Cambridge, UK. No significant differences were observed in total cholesterol levels between men and women, and a quarter of the sample had concentrations above 6.5 mmol/l which is 250 mg/dl. There were significant sex differences in a number of risk factors with males having significantly higher prevalence of low high density lipoprotein, systolic and diastolic blood pressures, obesity, and smoking than women. About 8% of men and women were obese (as defined by a body mass index > 30), while 47% of men and 35% of women were mildly overweight (body mass index > 25). Two or more risk factors for coronary heart disease (high total cholesterol and/or hypertension and/or obesity) were present in 4% and 9% of older men and women respectively. Furthermore, about half the subjects had more than one risk factor for coronary heart disease.     

Influence of sex,age, body mass index,and smoking on alcohol intake and mortality.

OBJECTIVE--To examine the association between self reported alcohol intake and subsequent mortality from all causes and if the effect of alcohol intake on the risk of death is modified by sex, age, body mass index, and smoking. DESIGN--Prospective population study with baseline assessment of alcohol and tobacco consumption and body mass index, and 10-12 years'' follow up of mortality. SETTING--Copenhagen city heart study, Denmark. SUBJECTS--7234 women and 6051 men aged 30-79 years. MAIN OUTCOME MEASURE--Number and time of deaths from 1976 to 1988. RESULTS--A total of 2229 people died, 1398 being men. A U shaped curve described the relation between alcohol intake and mortality. The lowest risk was observed at one to six alcoholic beverages a week (relative risk set at 1). Abstainers had a relative risk of 1.37 (95% confidence interval 1.20 to 1.56) whereas those drinking more than 70 beverages a week had a relative risk of 2.29 (1.75 to 3.00). Among the drinkers, the risk was significantly increased only among those drinking more than 42 beverages a week. Sex, age, body mass index, and smoking did not significantly modify the risk function. The risk among heavy drinkers was slightly reduced when smoking was controlled for. The risk function was similar in the first and second period of six years of observation. CONCLUSION--Alcohol intake showed a U shaped relation to mortality with the nadir at one to six beverages a week. The risk function was not modified by sex, age, body mass index, or smoking and remained stable over 12 years.     

Physiological and anthropometric characteristics of elite women rugby league players

This study investigated the physiological and anthropometric characteristics of elite women rugby league players and developed physical performance standards for these athletes. Thirty-two elite women rugby league players underwent measurements of standard anthropometry (body mass, height, sum of 7 skinfolds), muscular power (vertical jump), speed (10-, 20-, and 40-m sprint), agility (505 test), glycolytic capacity (glycolytic agility test), and estimated maximal aerobic power (multistage fitness test). The skinfold thickness, speed, agility, vertical jump height, glycolytic capacity, and estimated maximal aerobic power results were 6.0-38.1% poorer than previously reported for elite women team sport athletes (e.g., rugby union, soccer, and hockey). Although no significant differences (p > 0.05) were detected between selected and nonselected players for any of the physiological or anthropometric characteristics, significant differences (p < 0.05) were detected between forwards and backs for body mass, skinfold thickness, 10-, 20-, and 40-m speed, and estimated maximal aerobic power. When data were analyzed according to positional similarities, it was found that the hit-up forwards positional group were heavier, had greater skinfold thickness, and had lower 10-, 20-, and 40-m speed, muscular power, glycolytic capacity, and estimated maximal aerobic power than the adjustables and outside backs positional groups. The results of this study show that elite women rugby league players have slower speed and agility, lower muscular power, glycolytic capacity, and estimated maximal aerobic power, and greater body mass and skinfold thickness than previously reported for other elite women team sport athletes. These findings show the need to develop all physiological parameters to allow elite women rugby league players to more effectively tolerate the physiological demands of competition, reduce fatigue-related errors in skill execution, and decrease the risk of injury.     

Skinfolds and coronary heart disease risk factors are more strongly associated with BMI than with the body adiposity index

Objective:

A recent, cross‐sectional analysis of adults found that the hip circumference divided by height^1.5 minus 18 (the body adiposity index, BAI) was strongly correlated (r = 0.79) with percent body fat determined by dual energy X‐ray absorptiometry. The BAI was proposed as a more accurate index of body fatness than BMI. We examined whether BAI was more strongly related, than was BMI and waist circumference, to skinfold thicknesses and levels of various risk factors for coronary heart disease.

Design and Methods:

Cross‐sectional analyses of adults (n = 14,263 for skinfold thickness; n=6291 for fasting lipid levels) in the National Health and Nutrition Examination Survey (NHANES) III, 1988‐1994.

Results:

As compared with BMI and waist circumference, we found that BAI was less strongly associated with the skinfold sum and with risk factor levels. For example, correlations with the skinfold sum were r = 0.79 (BMI) vs. r = 0.70 (BAI) among men, and r = 0.86 (BMI) vs. r = 0.79 (BAI) among women; p < 0.001 for the difference between each pair of correlations. An overall index of the 7 risk factors was also more strongly associated with BMI and waist circumference than BAI in analyses stratified by sex, race‐ethnicity and age. Multivariable analyses indicated that if BMI was known, BAI provided little additional information on risk factor levels.

Conclusions:

Based on the observed associations with risk factor levels and skinfold thicknesses, we conclude that BAI is unlikely to be a better index of adiposity than BMI.     

Body build related body composition and nutrition in adulthood--a comparison of skinfold thickness measurement and bioelectric impedance analysis

The objective of the present study was to conduct a comprehensive analysis of body build, body composition and nutritional status. The study sample consists of 498 men and women aged from 35 to 65 years. Subjects underwent a detailed anthropometric examination incompassing thirty-one body measurements, eleven skinfold thickness measurements, and bioelectrical impedance analysis for determination of body composition. Dietary intake was assessed by a semiquantitative food frequency questionnaire. Body composition was clearly associated with age and body build. Somatometric differentiation by use of the metric index showed that percentage of body fat was significantly higher in pycnomorphic compared to leptomorphic subjects, whereas reported dietary energy intake was lower. Comparison of estimates of body fat showed considerably deviating results for skinfold thickness measurements and bioelectrical impedance analysis depending on the equations used. This was especially pronounced in obese subjects, where, on an average, bioelectrical impedance analysis resulted in higher values for percentage of body fat compared to skinfold thickness measurements. We conclude that for assessment of nutritional status body composition should be investigated taking into account body build in addition to age and sex.     

Obesity and weight gain are associated with increased incidence of hyperinsulinemia in non-diabetic men.

We investigated the temporal relationships between obesity, weight change and hyperinsulinemia in a population-based 4-year follow-up study of 695 middle-aged, non-diabetic, and normoinsulinemic men. Thirty-eight men developed hyperinsulinemia during the follow-up (fasting serum insulin > or = 12.0 mU/l). In logistic regression analysis adjusting for other risk factors, men with body mass index of > or = 26.7 kg/m2 (highest third) had a 6.6-fold (p = 0.001) risk of developing hyperinsulinemia, compared with men with body mass index of < 24.4 kg/m2 (lowest third). Correspondingly, men with waist-to-hip ratio of > or = 0.95 (highest third) had a 3.5-fold (p = 0.028) incidence of hyperinsulinemia compared with men with waist-to-hip ratio of < 0.90 (lowest third). Weight gain in middle age and weight gain from the age of 20 years to middle age were also associated with increased risk of hyperinsulinemia. Hyperinsulinemia at baseline was not associated with weight gain during the follow-up. This prospective population-based study emphasizes the importance of avoiding obesity and weight gain during adulthood in preventing hyperinsulinemia.     

Educational status,coronary heart disease,and coronary risk factor prevalence in a rural population of India.

OBJECTIVE--To define the association between educational level and prevalence of coronary heart disease and coronary risk factors in India. DESIGN--Total community cross sectional survey with a doctor administered questionnaire, physical examination, and electrocardiography. SETTING--A cluster of three villages in rural Rajasthan, western India. SUBJECTS--3148 residents aged over 20 (1982 men, 1166 women) divided into various groups according to years of formal schooling. RESULTS--Illiteracy and low educational levels were associated with less prestigious occupations (agricultural and farm labouring) and inferior housing. There was an inverse correlation of educational level with age (rank correlation: mean -0.45, women -0.49). The prevalence of coronary heart disease (diagnosed by electrocardiography) was significantly higher among uneducated and less educated people and showed an inverse relation with education in both sexes. Among uneducated and less educated people there was a higher prevalence of the coronary risk factors smoking and hypertension. Educational level showed a significant inverse correlation with systolic and diastolic blood pressure. Logistic regression analysis with adjustment for age showed that educational level had an inverse relation with prevalence of electrocardiographically diagnosed coronary heart disease (odds ratio: men 0.82, women 0.53), hypertension (men 0.88, women 0.56), and smoking (men 0.73, women 0.65) but not with hypercholesterolaemia and obesity. The inverse relation of coronary heart disease with educational level abated after adjustment for smoking, physical activity, body mass index, and blood pressure (odds ratio: men 0.98, women 0.78). CONCLUSION--Uneducated and less educated people in rural India have a higher prevalence of coronary heart disease and of the coronary risk factors smoking and hypertension.     

Are optimal levels of testosterone associated with better cognitive function in healthy older women and men?

Background

Sex steroids can positively affect the brain and from this it would follow that high levels of sex steroids could be associated with better cognitive function in older men and women.

Methods

This Healthy Ageing Study sample comprised of 521 older participants (51% women) without dementia at baseline, with an age range from 64 to 94 years. Testosterone and sex hormone binding globulin were measured using the automated Immulite 2000 and analyzed in association with baseline memory, global cognitive function and decline (assessed using the Mini-Mental Status Examination or MMSE) and controlling for potential confounds such as age, education, vascular disease, smoking, diabetes, thyroid function, and body mass index.

Results

In healthy older men and women, optimal levels of testosterone were associated with better MMSE scores at baseline. Follow-up analyses indicated that in men, low testosterone levels (OR = .94, 95% CI = .88 to 1.00) were a risk factor for a sharp cognitive decline after 2 years, perhaps indicative of dementia. Associations were independent of covariates and baseline MMSE. Conversely, women at risk for a sharp drop in cognitive function showed some evidence for higher calculated free testosterone levels at baseline.

Conclusions

Results replicate earlier cross-sectional findings that high levels of sex steroids are not associated with better cognitive function in older people. In men, age accelerated endocrinological change could be associated with dementia pathology.

General significance

These data do not support increasing testosterone levels to prevent cognitive decline in men and women over 65 years of age.