Indices of relative weight and obesity

Cigarette smoking and risk of breast cancer: a prospective study of 24,329 Norwegian women

The association between cigarette smoking and incidence of breast cancer has been analyzed in 242 cases of breast cancer that developed among 24,329 Norwegian women over 11-14 years of follow-up. At baseline they were aged 35-51. There was no overall association between cigarette smoking and the risk of breast cancer. The age-adjusted incidence rate ratio (IRR) was unity (IRR = 1.04, 95% CI 0.76-1.42) for regular smokers (10 or more cigarettes daily) compared with non-smoking women. In women who reported smoking between 1 and 9 cigarettes per day there was an age-adjusted IRR of 1.28 (95% CI 0.95-1.73). The lack of association with cigarette smoking was replicated in subgroup analyses of women diagnosed before age 51 ("premenopausal") and among women diagnosed after this age ("postmenopausal"). However, there was a significant interaction between cigarette smoking, body mass index and age at diagnosis (P = 0.01), which might indicate that an interaction between cigarette smoking and body mass exerts differential effects on breast cancer risk in premenopausal and postmenopausal women.

Management strategies for weight control. Eating, exercise and behaviour

Obesity is a major health and social problem worldwide for which no single satisfactory treatment exists. Because of the prevalence of the disease, numerous therapeutic strategies have been attempted--often unsuccessfully. Weight loss programmes based on dietary restriction of caloric intake and nutritional education, exercise, surgical (gastroplasty, gastric bypass) and procedural (gastric balloon, waist cord, jaw wiring, liposuction) intervention and pharmacotherapy (appetite suppressants, thermogenic agents, bulking agents) used alone or in combination, have produced weight loss in the short to medium term; however, weight is generally regained on discontinuation of treatment. Behaviour modification programmes appear to offer the highest success rate in the long term. Weight loss is not rapid, although losses of 10 to 15 kg have been achieved after 6 months, and this may be increased when behaviour modification therapy is combined with more aggressive treatments such as severe caloric restriction or jaw wiring. Behaviour modification is particularly beneficial in special patient groups such as the obese elderly, children or adolescents, and disabled patients. Thus, although it appears that each of the treatments developed for the management of obese patients has its place, the cornerstone of therapy for most patients remains a programme of dietary restriction, combined with exercise and behaviour modification.

Endometrial stromal sarcoma: review of Mayo Clinic experience, 1945-1980

Uterine sarcomas are uncommon malignancies. We retrospectively examined 24 cases of "high grade" endometrial stromal sarcomas (ESS). The histologic diagnosis was made if there was a high grade sarcoma with a high mitotic index and nuclear anaplasia. Heterologous elements could be present, if focal only. Leiomyosarcomas, mixed mesodermal sarcomas, and carcinosarcomas were excluded. Mitotic index was expressed as the number of mitoses per 10 high-power fields in active areas. Tumor grade was based on nuclear anaplasia. ESS were 5.7% of all uterine sarcomas. Median age was 58.2 years; median duration of symptoms was 67.5 days. Abnormal bleeding was the presenting complaint in 91.7%. Uterine enlargement was seen in 33%; protrusion through the cervical os was seen in 9 cases. Total abdominal hysterectomy and bilateral salpingo-oophorectomy was performed in 95.8%. Twenty patients had myometrial involvement; 5 patients had serosal spread and extrauterine disease; residual disease was seen in 3 patients. Adjuvant radiation was not beneficial. Ten patients had recurrences: 60% in the pelvis, 50% each with subcomponent of abdominal or distant disease. Overall survival was 3.4 years and was significantly associated with extent of disease, size of the primary tumor, and grade.

Importance of overweight in studies of left ventricular hypertrophy and diastolic function in mild systemic hypertension

The relations of Metropolitan Life Insurance Co. Relative Weight values and blood pressure (BP) to minimal forearm vascular resistance, ventricular septal and posterior wall thickness, left ventricular (LV) mass index and cardiac diastolic function were assessed in 31 men, 37 +/- 2 (mean +/- standard error of the mean) years of age. Eighteen patients with untreated mild hypertension were compared with 13 normotensive control subjects of similar age and weight. The hypertensives had higher clinic (137 +/- 3/96 +/- 2 vs 121 +/- 4/81 +/- 3 mm Hg, p less than 0.001/less than 0.001) and home (p less than 0.001) BP. Despite higher BP, the hypertensives did not have significantly greater values than normotensives, respectively, for minimal forearm vascular resistance (2.20 +/- 0.12 vs 2.04 +/- 0.11 U), ventricular septal (9.9 +/- 0.5 vs 10.2 +/- 0.3 mm) and posterior wall thickness (10.2 +/- 0.4 vs 10.0 +/- 0.3 mm) or LV mass index (106 +/- 6 vs 107 +/- 6 g/m2). Furthermore, diastolic peak filling rate, an index of LV diastolic function, was virtually identical in the 2 groups (2.71 +/- 0.14 vs 2.69 +/- 0.07 liters/s, difference not significant). Correlates of peak filling rate included relative weight (r = -0.62, p less than 0.001), posterior wall thickness (r = -0.51, p less than 0.01) and age (r = -0.45, p less than 0.05). Relative weight also correlated significantly with posterior wall (r = 0.59, p less than 0.005), ventricular septal (r = 0.47, p less than 0.005) and LV mass index (r = 0.38, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Mitral leaflet motion: age and implications for the diagnosis of mitral valve prolapse

The extent of posterior mitral leaflet motion (PMLM) during systole in relation to age was studied in 300 asymptomatic men aged 18-42 years. PMLM of 4 mm or more on two-dimensional directed M-mode echocardiography was found in 8% (16/200) of subjects under age 35 years, but in only 2% (2/100) of those aged 35 years or more (p less than 0.05). On two-dimensional echocardiography, 16% (31/200) of men under 35 years old had PMLM greater than or equal to 0.40 mm2 compared with 1% (1/100) of those 35 years or more (p less than 0.001). The findings were not related to differences in left ventricular cavity dimensions or in the extent of systolic ventricular contraction. Body mass index (BMI) increased with age, but there was a significant and independent negative correlation of age with PMLM after controlling for BMI. The data are compatible with the hypothesis that the aging process is associated with decreased mobility of the mitral valve or annulus with lesser degrees of backward bowing or billowing of the leaflets during systole. Age should be taken into account in determining "normal" values for mitral leaflet motion.

Induction of ovulation with gonadotrophin-releasing hormone--life-table analysis of 50 courses of treatment

Ovulation induction by means of the pulsatile subcutaneous administration of gonadotrophin-releasing hormone by way of an infusion pump is described. The clinical outcome in 50 courses of treatment, which totalled 116 treatment cycles, was analysed and was compared with the pregnancy rates that were obtained with the administration of human pituitary gonadotrophins. We found that the pregnancy rates for these two treatments were similar. We also have shown that for those women who ovulated as a result of such treatment the conception rates were similar to those in ovulatory women who had discontinued contraception. We conclude that gonadotrophin-releasing hormone has an important place among the ovulation-induction agents.

Obesity: basic considerations and clinical approaches

Obesity, defined as an excess of body fat, can be measured with a variety of techniques, but in most epidemiologic studies it is estimated from height and weight or from skinfold thickness. The "gold standard" for body fat is the body density from which fat and fat-free body mass can be calculated. The new technique of bioelectric impedance analysis may substantially improve the estimation of total body fat. For estimating regional fat distribution, either waist to hip circumference ratio or subscapular skinfold have been most useful. Using the body mass index, defined as weight in kilograms divided by the square of the height in meters (kilogram per square meter), the National Health and Nutrition Examination Survey estimated that 26%, or 34 million, adult Americans aged 20 to 75 were overweight. The prevalence of severe overweight (a body mass index above 30 kg/m2) is higher in the United States and Canada than in Great Britain, the Netherlands, or Australia. Obesity results from an increase in energy intake relative to expenditure. Total daily energy expenditure includes energy used during resting metabolism, energy associated with the ingestion of food, and energy needed for physical activity. The obese are often observed to be less active, but since carrying a heavier load requires more energy, their total energy expenditure may not be low. A low resting metabolic rate has been suggested as a predictor of future risk of becoming obese. Adipose tissue is the major site for fat storage and may contain more than 90% of total energy stores. The increase in body mass index or degree of body weight is associated with an increased risk of heart disease, hypertension, gall bladder disease, and diabetes mellitus. When fat is centrally located in either males or females, the risk for these diseases is also increased, and may be a more important risk factor than total overweight itself. Genetic factors form the background from which obesity develops. The best estimates suggest that these genetic factors may be of less importance than environmental events in determination of total body fat and its distribution. Obesity can be classified on the basis of the total number of fat cells and regional fat distribution by using the etiological factors which caused the obesity or by determining the age at which the obesity began. Regardless of the cause, treatment for obesity should be based on an evaluation of the individual's risk from obesity as compared with the risk of the treatment under consideration. (ABSTRACT TRUNCATED AT 400 WORDS)

The Stanford Adolescent Heart Health Program

This study was designed to create, implement, and test a school-based multiple risk factor reduction program for high school students. All tenth graders in four senior high schools (N = 1447) from two school districts participated in the study. Within each district, one school was assigned at random to receive a special 20-session CVD risk reduction intervention and one school served as a control. The schools were matched for size and distribution of racial groups before randomization. At a two-month follow-up, knowledge gains were significantly greater for students in the treatment group on each of the risk factor domains tested: nutrition/diet (p less than 0.0001), physical activity (p less than 0.0001), and cigarette smoking (p less than 0.0001). Compared to controls, a higher proportion of those in the treatment group who were not exercising regularly at baseline, reported regular exercise at follow-up (p less than 0.0003). Almost twice as many baseline experimental smokers in the treatment group reported quitting at follow-up while only 5.6% of baseline experimental smokers in the treatment group graduated to regular smoking compared to 10.3% in the control group (p = 0.009). Students in the treatment group were more likely to report that they would choose heart healthy snack items (p less than 0.0001). Beneficial treatment effects were observed for resting heart rate (p less than 0.0001), BMI (p = 0.05), triceps skinfold thickness (p = 0.003), and subscapular skinfold thickness (p = 0.01). The results suggest that it is feasible to provide CVD risk reduction training to a large segment of the population through school-based primary prevention approaches.

The relation of body fat distribution, as assessed by six girth measurements, to diabetes mellitus in women

Independently of the amount of adipose tissue, certain patterns of fat distribution increase the risk of non-insulin-dependent diabetes. Although the ratio of waist to hip (WHR) circumferences has been consistently related to diabetes mellitus, it is possible that only two measures do not completely characterize fat topography. The current study, therefore, examines the cross-sectional relation of six girths (waist, hip, neck, bust, wrist, and ankle) to diabetes mellitus in 43,595 women. As compared with non-diabetics, Quetelet index (kg/m2) and all circumferences were elevated among diabetics. Stratified analyses showed that WHR, and waist, neck, and bust girths were consistently related to diabetes independently of the degree of overweight. As estimated from a logistic regression model that simultaneously controlled for age and all anthropometric variables, the prevalence of diabetes mellitus was positively related to Quetelet index, and to the waist, bust, and neck girths, with odds ratios (ORs) ranging from 1.4 to 2.6. However, diabetes was inversely related to hip (OR = 0.61) and ankle (OR = 0.73) girths; p less than 0.005 for each association. Although cross-sectional in nature, these results suggest that an adverse body fat distribution is not limited to the abdominal region, but that a relative preponderance of adipose tissue in various regions of the upper body is associated with diabetes mellitus in women.

Longevity of man: relative weight and fatness in middle age

By February, 1948, examinations in the Twin Cities Prospective Study were completed on 284 executive men, then aged 45-55 and "healthy". In 35 years 183 died, 110 were alive, one was lost. Entry body fatness, indicated by body mass index, skinfold thickness at three sites, relative girth, and body density, did not significantly discriminate the 35-year dead from survivors. Age at death was not related to any fatness measure. The multiple logistic equation in five solutions using age, blood pressure and smoking plus each fatness item separately, found no discrimination of dead from survivors by any fatness measure. In other long time prospective studies, two suggested excess mortality at far extremes of over- and under-weight, several found survivors significantly fatter than the dead, others found no relation between fatness and longevity. Framingham reported fatness a risk factor for death when allowance is made for smoking but that singular claim has been criticized.

Investigation of osteopaenia in anorexia nervosa

Sixty-nine female patients, mean age 27.5 years (range 20-40), with a past or current history of anorexia nervosa (DSM III-R) had spinal trabecular bone density assessed by single energy quantitative CT scan. Current exercise and dietary calcium levels were assessed by detailed questionnaires and categorized. A semi-structured interview was used to record weight, menstruation, exercise and dietary calcium intake histories from early adolescence. Serum sex hormones and total calcium assays were measured. Bone density was significantly lower in the patients compared to 31 controls. Bone density was significantly positively correlated with body mass index, and negatively correlated with illness duration and duration of amenorrhoea. Exercise levels, dietary calcium intake and taking an oestrogen pill did not correlate significantly with bone density. Recovered patients did not have osteopaenia but they had shorter illness histories than non-recovered patients. Management to minimise bone loss should focus on weight gain and resumption of normal menstruation.

Increased 22Na+-influx in lymphocytes from offspring of essential hypertensive patients

Lymphocytes were used as a cellular model for the in vitro measurements of 22Na+-influx during sodium pump inhibition by ouabain. The measurements were made using lymphocytes from young men at increased risk of developing essential hypertension in order to assess any changes and to analyse whether any such changes were associated to borderline hypertension and/or heredity. Four groups were evaluated: 28 normotensive and 20 borderline hypertensive offspring of hypertensives, 12 borderline hypertensives and 28 normotensives with normotensive parents. 22Na+-influx was significantly increased in offspring of hypertensive parents especially in the normotensive offspring of hypertensive parents. The association between heredity and increased 22Na+-influx found by us in vitro may be caused by either an increased passive sodium-influx and/or an increased sodium-sodium exchange mechanism.

Randomized trial to evaluate the addition of tamoxifen to cyclophosphamide, 5-fluorouracil, prednisone adjuvant therapy in premenopausal women with node-positive breast cancer

A randomized clinical trial was performed to determine if the addition of hormonal therapy with tamoxifen to a combination chemotherapy regimen was superior to the chemotherapy alone for adjuvant treatment of premenopausal women after mastectomy for node-positive breast cancer. The chemotherapy regimen utilized consisted of cyclophosphamide (C), 5-fluorouracil (F), and prednisone (P), and the doses employed were: C, 150 mg/m2 IV days 1 to 5; F, 300 mg/m2 IV days 1 to 5; and P, 10 mg orally three times daily on days 1 to 7. A total of ten courses of therapy, given every 6 weeks, was planned. Tamoxifen (T) was given at a dose of 10 mg twice daily and was stopped 6 weeks after the last course of CFP. Four hundred patients are fully eligible and evaluable. With a median observation time of 5.3 years, the proportion of recurrences on each arm were: CFP, 95 of 202 (47%); CFPT, 77 of 198 (39%). The relapse-free survival distribution for CFPT was superior to that for CFP, at a borderline level of significance (two-sided P = 0.06). When significant prognostic factors were considered in covariate analysis, CFPT was not significantly better than CFP (P = 0.43). This marked change in level was due to imbalance in several factors not considered in stratification. Currently, 31% of CFP and 25% of CFPT patients have died, and although there is a slight separation of the survival curves in favor of CFPT, the difference is not significant (P = 0.21). Analysis within receptor subsets also showed no significant advantage for the addition of tamoxifen. This study does not establish a significant advantage for the concurrent administration of tamoxifen with the CFP regimen. It does, however, clearly demonstrate the importance of examination of clinically important prognostic factors, even those not utilized in stratification, and consideration of these factors in covariate analysis if imbalances are present.

The struggle to be thin: a survey of anorexic and bulimic symptoms in a non-referred adolescent population

Ninety-one per cent of a county-wide high school population (N = 5596) completed the Eating Symptoms Inventory (ESI) and the Eating Attitudes Test (EAT). Being female, older and heavier are far more strongly associated with anorexic and bulimic symptoms than is social class. ESI approximations of the DSM-III criteria for anorexia nervosa or bulimia suggest that while both conditions are rare (less than 1%), bulimia is the more prevalent disorder.

Increased number of ouabain binding sites in lymphocytes from borderline hypertensives

Lymphocytes were used as a cellular model for the in vitro measurements of maximal ouabain binding sites in order to assess any changes in young men at increased risk of developing essential hypertension, and to analyse whether any such changes were associated to borderline hypertension and/or heredity. Four groups were evaluated; 28 normotensive (NTO) and 20 borderline hypertensive (BHO) offspring of hypertensives. Twelve borderline hypertensives (BH) and 28 normotensive subjects (NT) with normotensive parents. The number of ouabain binding sites were significantly increased in the borderline hypertensives irrespective of heredity. The borderline hypertensives were heavier than the normotensives. A stepwise multiple regression model was therefore used in order to control confoundings by body mass index (BMI) and other factors such as age, gamma glutamyl transferase, 24 h sodium excretion, serum triglyceride, and serum cholesterol, which may influence the number of ouabain binding sites. Only BMI entered the stepwise model. These results indicate the presence of an increased number of sodium-potassium pumps in lymphocytes from borderline hypertensives. This difference may be attributed to the blood pressure disease or increased body mass.

The other face of development: native population, health status and indicators of malnutrition--the case of the Cree and Inuit of northern Quebec

The cultural setting of the isolated Cree Indian and Inuit communities is described and measures of their health examined. Questionnaires were employed to consider both epidemiological and socio-cultural facets and physical examination evaluated serological indicators of nutritional status. Changes of lifestyle toward store purchased food and a lessened reliance on hunting and fishing along with the non-native nature of the health services available seem to be leading to heart conditions, hypertension and diabetes all of which give cause for concern.

Diagnosis and prevalence of obesity

Obesity is a condition of increased adipose tissue mass. Many techniques are available for measurement of body fat, but none is available widely for clinical purposes. The new technique of bioelectrical impedance may change this in the future. For now, relative weight and BMI are used as indices of obesity, which may be defined as a BMI greater than 30 kg per m2. This corresponds to a relative weight approximately 120 per cent above desirable. According to this definition, obesity exists in 10 to 12 per cent of adult men and women in the United States and Canada.

Serum potassium concentrations following succinylcholine in patients undergoing beta-adrenoceptor blocking therapy

Efflux of serum potassium following succinylcholine was compared in surgical patients undergoing low-dose, long-term beta 1-adrenoceptor or beta 1,2-adrenoceptor blocking therapy and in those receiving neither of these therapies. There were no significant differences in serum potassium concentration prior to, and over a study period of, 2 hours following succinylcholine administration among the three groups of patients.

Transcutaneous CO2 monitoring in adults with sleep-related breathing disorders

The accuracy of transcutaneous CO2 monitoring (PtcCO2) was studied in 22 subjects suspected of having sleep-related breathing disorders, by comparison with arterial CO2 measurements (PaCO2). At rest 40 simultaneous sets of PaCO2 and PtcCO2 were obtained. The mean PaCO2 (+/-SD) was 5.3 +/- 0.9 kPa and PtcCO2 was 5.7 +/- 1.0 kPa (r = 0.79). The ventilatory response to CO2 was evaluated by a CO2 rebreathing method, and simultaneous measurements of PaCO2, PtcCO2 and end-tidal PCO2 (PETCO2) were made every min. Both PaCO2 and PETCO2 increased more during the first min of CO2 rebreathing than PtcCO2 (p less than 0.001). Between 1 to 5 min after the start of rebreathing there were no significant differences between the three methods. During sleep there was an increase in PtcCO2 (by 0.1-0.3 kPa) with each apneic event, the magnitude of the increase depending on the length and distribution of these events. With repeated long apneas there was a cumulative increase in PtcCO2, especially during REM sleep. Continuous PtcCO2 monitoring proved useful in monitoring and diagnosing sleep-related breathing disorders.

When to advise surgery for severe obesity

A typical severely obese patient will have about 50 kg excess weight to lose, which is equivalent to a store of 350,000 kcal. The optimum rate of weight loss in such a patient is about 1 kg/week, which involves an energy deficit of 1000 kcal/day for about a year. It is difficult to maintain this degree of dietary restriction over such a long period, and procedures such as jaw wiring or stomach stapling may help in some cases. Maintenance of weight loss is difficult to achieve and may be helped by fitting a nylon waist cord after weight loss. On theoretical grounds, patients who do not lose weight despite keeping to a properly-designed reducing diet would not benefit from surgery, but in practice this problem does not arise. It is dangerous to resort to surgery for the treatment of severely obese patients who cannot diet by reason of psychiatric disorder.

Timing of prophylactic antibiotics in abdominal surgery: trial of a pre-operative versus an intra-operative first dose

When prophylactic antibiotics are used in abdominal surgery it is customary to give the first dose before the operation. Whilst intra-operative antibiotics may be effective in elective surgery, there may be an advantage to starting pre-operatively when there is already an infective focus such as appendicitis. Antibiotics started pre-operatively (group P) have been compared with antibiotics started after initial abdominal exploration (group T). Three intravenous doses of 500 mg metronidazole plus 1 g cephazolin were given in a randomized, double-blind study of 700 emergency and elective high-risk abdominal operations. Antibiotic plasma concentrations at the end of the operation were significantly lower in group P but lay well within the therapeutic range. Wound infection rates, which included minor and delayed infections, were similar in both groups (group P, 57 of 342, 16.7 per cent; group T, 55 of 358, 15.4 per cent; 95 per cent confidence intervals for the difference being -4.1 to +6.7 per cent. In appendicitis, wound infection rates were 12.1 and 13.9 per cent for groups P and T respectively. However, non-fatal deep sepsis was more common in group P (nine cases) than in group T (two cases) (chi 2 = 4.9, P less than 0.05). Postoperative infection was twice as common in obese patients whose body mass index (BMI) was greater than or equal to 26 (39 of 132, 30 per cent) than in thin patients whose BMI was less than 24 (41 of 288, 14 per cent; chi 2 = 13.8, P less than 0.001). This study failed to show any advantage to starting antibiotics pre-operatively, even in appendicitis.

Insulin response to a short stress period

In 24 healthy volunteers (seven women, 17 men; mean age 23 +/- 5 years), we studied the insulin response to a short stress period of 30 min, induced by cognitive conflict under social pressure. Insulin, growth hormone (GH), blood glucose and blood pressure (BP) determinations were performed before and after the stress period. There was a significant increase in insulin levels following the stress period (p = 0.02, paired t-test). A multiple stepwise regression analysis, with insulin difference as the dependent variable and initial GH and blood sugar levels, their increments and body mass index as predictors, showed that insulin variation was independent of any of the predictors. We discuss the influence of autonomic innervation on insulin secretion and the possible change in insulin sensitivity during stress.

Health risks of obesity

Evidence implicating obesity as a risk-factor disease is critically reviewed. Possible reasons for the many conflicting findings are addressed. The classification of obesity, based upon the site of body fat distribution, and possible biologic mechanisms associating regional adiposity with morbidity, are discussed.

Relationship of the body mass index with skinfolds, girths, and bone breadths in Canadian men and women aged 20-70 years

The relationship of Quetelet index (w/h2), or body mass index (BMI), with the sum of skinfolds at five sites, two skinfold-corrected limb girths, and two bone breadths were studied in a cross-sectional sample of 12,282 men and 6,593 women aged 20-70 years. The correlations of the BMI with skinfolds (0.50), bone breadths (0.51), and girths (0.58) were too low for individual prediction. Contingency tables of the BMI and sum of skinfold categories further indict its use for the purpose of assessing adiposity status or monitoring change in individuals.

Glucose and insulin response in diabetic subjects: acute effect of carbohydrate level and the addition of soy polysaccharide in defined-formula diets

This single-meal pilot study compared the plasma glucose and serum insulin response to defined-formula diets with two levels of carbohydrate (CHO) (55% and 30% of the kilocalories) with and without added soy polysaccharide (10 g) in subjects with type 2 diabetes mellitus. Subjects received each of the four liquid-formula test meals in a randomly assigned order: 1) high CHO, low fiber (HC, LF), 2) high CHO, high fiber (HC, HF), 3) low CHO, low fiber (LC, LF), and 4) low CHO, high fiber (LC, HF). On the day of each test meal the formula was consumed, eight blood samples were drawn for plasma glucose and serum insulin measurements, and a 4-h urine collection was obtained for measuring glucose excretion. Our results showed that area increments under glucose and insulin curves were significantly lower with both low-CHO formulas (p less than 0.001). The addition of soy polysaccharide to the liquid formula did not result in statistically different area increments for glucose or insulin.

Changes of erythrocyte membrane fluidity associated with childhood obesity: a molecular study using fluorescence spectroscopy

Fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene has been used to investigate the physical state of erythrocyte membranes from 36 obese children in absence of endocrine and metabolic disorders involving alterations of blood lipid pattern. A decrease of membrane fluidity, as shown by an increase of fluorescence polarization, was evident in obese subjects in comparison with the controls. The study of membrane composition has revealed an increase of cholesterol content and of cholesterol to phospholipid molar ratio, both being positively correlated with the observed changes of membrane fluidity. Moreover a correlation of membrane fluidity is also observed with body-mass index and plasma cholesterol levels. The results are discussed in the light of the possible use of erythrocyte membrane as a model to detect early alterations in the exchanges between erythrocyte membrane and lipoproteins in obesity.

Weight, height and body mass index in the prognosis of breast cancer: early results of a prospective study

The hypothesis that obesity plays a role in the prognosis of breast cancer is examined in this preliminary analysis of a follow-up study of 472 early-stage breast cancer patients. The 75th percentile values of weight (= 73 kg) and body mass index (BMI = 28) in the total patient population were taken as the cut points for estimating overweight or "obesity". Stratified, survival, and logistic regression analyses showed that increased weight or BMI, but not height, were associated with increased risk recurrence. In the logistic regression analysis, after accounting for other risk factors, stage III was a negative prognostic indicator of recurrence (with stage I as the referent group, OR = 3.46, 95% CI: 1.36-8.81). Women whose weights were above the 75th percentile value had a significantly increased risk of recurrence in relation to the other women (OR = 3.55, 95% CI: 1.65-7.65). Results from a model substituting BMI for weight showed a similar significant result. The adequacy of using anthropometric indices as proxies for obesity and various biological mechanisms, which may explain the relationship, are discussed.

Sex steroid-binding protein in nonendocrine diseases

In humans, sex steroid-binding protein (SBP) is a protein from the liver which binds with high affinity sex steroid hormones. The plasma concentration of SBP is regulated in part by hormonal factors. It has been shown that estrogens and/or thyroid hormones increase the production of SBP by hepatoma cell lines. It is therefore assumed that the increase in SBP levels in patients given oral estrogens or thyroid hormones is the consequence of a direct stimulation of the liver production of SBP by these hormones. The effects of androgen, progestagen and glucocorticoid hormones are unclear or still a matter of controversy. Moreover, the regulation of the metabolic clearance rate of SBP and the influence of nonhormonal factors on the production of SBP are still speculative. Changes in SBP have been described in a few nonendocrine diseases. A slight hormonal dysfunction may be either the primary or the sole cause of the changes in SBP occurring in these diseases. As an example, elevated SBP levels have been reported in men with liver cirrhosis together with testicular hypofunction and increased estrogen levels. It is therefore difficult to demonstrate that the increase in SBP is due to the liver dysfunction rather than to the endocrinological side effects of cirrhosis. The aim of this review is to present some aspects of the nonhormonal regulation of SBP. There is accumulating evidence in the literature for a relation between SBP levels and body weight and fat distribution, energy balance, diet and physical activity, and lipid metabolism. Therefore, it is tempting to propose that SBP is an index which reflects the status of endocrine, metabolic and nutritional functions. Measurement of SBP may be considered of interest in the light of previous epidemiological studies and the preventive approach to diseases such as hormone dependent tumors, cardiovascular diseases and osteoporosis.

Obesity and insulin resistance: lessons learned from the Pima Indians

Diabetes and obesity are epidemic in the Pima Indians of the Southwestern United States, and the prevalence of diabetes is increasing. The most likely link between obesity and diabetes is tissue insulin resistance. If obesity is defined as an excess of body fat, then it can only be accurately assessed by measurements of body composition and not by approximations such as body mass index or percent of ideal weight. To compare the metabolic data of individuals of varying size, an accurate measure of metabolic size is needed. Total body weight is not an appropriate means of comparing individuals since obese subjects have a greater proportion of nonmetabolizing mass (triglyceride). Body surface area shows a sex difference, and this may distort data if both sexes are present. From studies of metabolic rate we have determined that metabolic rate is directly proportional to the fat-free mass plus 18 kg, and we suggest that this weight can be equated with metabolic size. Glucose storage in skeletal muscle appears to be important in the disposal of an intravenous glucose load. Consistent with its role in glycogen storage, glycogen synthase enzyme is activated in proportion to the ability to dispose of glucose during a hyperinsulinemic, euglycemic clamp. The role of glycogen synthase is most notable at supraphysiological plasma insulin concentrations; and since glucose uptake at these insulin concentrations is highly familial independent of the degree of obesity, we suggest that there may be a specific genetic defect expressed in skeletal muscle that reduces insulin responsiveness in some subjects. The lack of correlation between 24 hour respiratory quotient measured in a metabolic chamber (a measure of the proportion of fat derived calories) and degree of obesity indicates that in obese Pima Indians insulin resistance is not due to an inhibition of glucose metabolism by free fatty acids (glucose-fatty acid-ketone cycle). Obesity is associated with an increase in fat-free mass almost kilogram- for kilogram with fat mass when compared to the lean state. A role for this increase in fat-free tissue in producing insulin resistance has been given insufficient attention in the past. With an increase in fat-free mass, muscle cells are hypertrophied and capillaries in muscle are more widely spaced. We propose that these biophysical changes in muscle mediate, at least in part, the effects of obesity to produce a reduction in insulin sensitivity and the abnormal kinetics of insulin action found in the obese.(ABSTRACT TRUNCATED AT 400 WORDS)

A biopsychosocial model of medical student distress

Medical student distress was examined in two consecutive first-year classes (N = 312) in September, before they interacted with the school regimen, and again in May before exams. Anxiety means were one SD above the normative mean for nonpatients at both times. The number of students reporting a significant level of depression doubled from September (N = 36) to May (N = 78). The correlation of distress in September and May was .40, indicating that for many students distress was enduring. A biopsychosocial model of initial distress explained more variance (36%) in the cross-validation sample than did any one variable alone. Distressed students had higher Type A scores. Also, anger held in was a risk factor for distress in students with a family history of cardiovascular disease (CVD). Students who hold anger in may experience prolonged stress which, coupled with a family history of CVD, could make them psychobiologically vulnerable to distress.

Lack of metabolic effects of a triphasic formulation containing norethindrone in normal women studied prospectively

The glucose and insulin responses to oral glucose tolerance tests and lipid values in normal women taking a triphasic pill containing norethindrone (Ortho 7/7/7) were performed. After three months, no significant changes in these metabolic indices were found. These results confirm and expand the knowledge regarding the metabolic safety of norethindrone-containing triphasic formulations.

Factors Associated With Shin Soreness in Athletes

In brief: Twenty-five exercisers suffering from shin soreness were interviewed, examined, and monitored to identify factors associated with this injury. Twenty-five uninjured persons who matched the injured subjects in age, sex, and activities served as controls. Injured subjects had a greater range of subtalar joint motion and increased ankle dorsiflexion, reported a significantly lower calcium intake, had raised their training intensity before injury, and were using worn or poorly made shoes when injured. Factors not associated with injury included number of months subjects had participated in weight-bearing exercise, exercise surface, amount of stretching, height-weight ratio, and menstrual status. This study is the first to indicate a possible relationship between nutrition and shin soreness.

Chronic calcific pancreatitis: clinical profile in northern India

Twenty three patients with chronic calcific pancreatitis of the tropics in Northern India were prospectively studied. All had pancreatic calcification and ERCP changes typical of chronic pancreatitis, the most predominant being ductal dilatation which was detected in all patients by both ERCP and by ultrasonography. Pain was present in 19 (83%) patients and diabetes in 11 (48%) patients. Exocrine pancreatic dysfunction was uncommon, steatorrhoea being present in only 9% of patients. Ten of the 11 patients with diabetes required insulin for control and one case was able to be controlled by an oral antidiabetic agent. Two patients developed ketoacidosis during acute episodes of pancreatitis, 3 patients had peripheral neuropathy and one patient had visual changes. Recurrent severe pain was the reason for operation in 7 patients. All had a lateral pancreaticojejunostomy. In order to obtain an objective assessment of pain, a scoring system was developed to grade its severity according to its intensity, frequency and consequences. Six patients who preoperatively had a pain score of 15 or more (out of a maximum score of 24) attained significant relief after the surgery. We feel this scoring system may provide an easy objective assessment of pain in the subsequent follow-up of these patients.

Black-white differences in aortic fatty streaks in adolescence and early adulthood: the Bogalusa Heart Study

Although white adults have more extensive aortic surface involvement with fibrous plaques than do blacks, adolescent blacks have more aortic fatty streaks (FS) than do whites of similar ages. Possible determinants of these racial differences in aortic surface involvement with FS were therefore examined in 44 decedents who had previously been examined as part of the Bogalusa Heart Study. Ages at death ranged from 6 to 27 years (mean, 18 years); the median interval between the last risk factor examination and death was 3.5 years. More extensive aortic surface involvement with FS was observed in blacks (n = 11) as compared with whites (n = 33; 37% vs 16%, p = .0003). This racial difference was independent of age at death, and was seen in both male and female subjects. Black-white differences in several of the previously measured risk factors (serum lipids and lipoproteins, blood pressure, and obesity) were also observed, and in both races, aortic FS were related to several of these characteristics. (For example, the correlation between levels of low-density lipoprotein cholesterol and aortic FS was 0.49 in whites and 0.73 in blacks.) However, even after controlling for antemortem levels of risk factors, blacks had an additional 16% surface involvement with aortic FS as compared with whites (p less than .001). These findings suggest that the more extensive surface involvement of the aorta with FS in young blacks is not due to differences in clinical risk factors. Because more extensive raised lesions are found in white adults, the transition of FS to advanced atherosclerotic lesions may differ in whites and blacks.

The theoretical bases of indirect calorimetry: a review

Indirect calorimetry is the method by which the type and rate of substrate utilization, and energy metabolism are estimated in vivo starting from gas exchange measurements. This technique provides unique information, is noninvasive, and can be advantageously combined with other experimental methods to investigate numerous aspects of nutrient assimilation, thermogenesis, the energetics of physical exercise, and the pathogenesis of metabolic diseases. Since its use as a research tool in metabolism is growing, the theoretical bases of indirect calorimetry are here reviewed in a detailed and orderly fashion. Special cases, such as the occurrence of net lipid synthesis or gluconeogenesis, are formally considered with derivation of explicit stoichiometric equations. The limitations of indirect calorimetry, both theoretical and technical, are discussed in the context of circumstances of clinical interest in metabolism.

Body fat distribution, plasma lipids, and lipoproteins

The relation of body fat distribution as measured by the ratio of waist to hip circumferences (WHR) to plasma levels of lipids and lipoproteins was studied in 713 men and 520 women who were employed by two Milwaukee companies. Quetelet index (kg/m2), waist girth, hip girth, and WHR were each positively related to levels of total cholesterol, triglycerides, apolipoprotein B, and the ratio of total to high density lipoprotein (HDL) cholesterol. In addition, the anthropometric measures were inversely associated with levels of HDL cholesterol. (Controlling for age, alcohol intake, exercise level, current smoking status, and oral contraceptive use only slightly reduced the strength of the correlations.) In addition, WHR and Quetelet Index were independently related to lipid and lipoprotein levels, and the magnitudes of the associations were roughly equivalent. For example, the mean (covariate-adjusted) triglyceride level among men in the upper tertile of the Quetelet Index was 37 mg/dl higher than for men in the lower tertile of the Quetelet Index; the corresponding difference according to WHR tertiles (upper to lower) was 39 mg/dl (p less than 0.01 for both effects). These findings indicate that in healthy men and women a less favorable lipid and lipoprotein profile is associated with elevated levels of both Quetelet Index and WHR.

Adiposity indices and clinical opinion

The comparison of various adiposity indices in children and adolescents shows that there is a great similarity between the indices, and also between their ability to distinguish extreme groups. The adiposity indices used are highly correlated with weight and subscapular skinfold thickness, and are not generally independent of height. Differences in these correlations appear during the period of puberty. Discrimination of obese and non-obese subjects by the indices and by clinical opinion agrees in 65%-75% of instances, with no one index agreeing better than the others.

Ear oximetry during progressive hypoxia

The BIOX III Pulse oximeter for measuring arterial oxygen saturation (SaO2) was compared during rest and under progressively hypoxic conditions, with SaO2 values based on arterial blood samples. The measurements were performed in 16 subjects undergoing tests of ventilatory response to hypoxia, by a rebreathing method. For each individual subject, there was a linear response relationship (r = 0.99), while for all 126 comparative values the regression equation was: y = 0.83 X + 14.7 (r = 0.98). The observed ventilatory response was lower when the calculations were based on oximeter readings. We conclude that the oximeter has acceptable correlation between the BIOX III and SaO2 measurements for clinical use, especially when SaO2 is above 70%.

Mother-daughter differences in menarcheal age in adolescent girls attending national dance company schools and non-dancers

A combination of genetic and environmental factors is thought to contribute to age of menarche. Adolescent athletes and dancers are much more likely to have a delayed menarche than are non-athletes. To examine the possible differential influence of heredity and environmental factors on menarcheal age, 350 adolescent dancers and non-dancers and their mothers were surveyed. The dancers had a later age of menarche than did the comparison group; their mothers did not differ with respect to menarcheal age, suggesting that delayed menarche in athletes is not solely due to genetic selection as inferred by maternal menarcheal age. Maternal menarcheal age was the best predictor of menarcheal age in the comparison sample, while leanness was in the dance sample.

Sports participation and health status: a preliminary analysis

This paper presents fresh evidence which examines health in relation to age, sex, socio-economic status, sport type and frequency amongst indoor sports participants. The evidence is from 4441 self-completed questionnaires by representative samples of adult participants in seven indoor sports at 46 separate sports facilities, in six U.K. cities. Six indicators of the respondents' health were inter-related and, for purposes of this analysis, are combined into a six-point scale, Males and females in all age groups who were taking part in the more physically demanding sports recorded the highest health scores. In addition, individuals who were playing these demanding sports more than once per week scored higher than those participating in the same activities less often. Health score was also found to be associated with other health-promoting lifestyle practices, such as never smoking and moderate alcohol consumption. Longitudinal corroboration will be necessary to confirm sport as a causal factor in the health-sport relationship, though the cross-sectional evidence from this enquiry is encouraging. It suggests that all types of physically demanding sport, competitive or not, offer measurable health gains to men and women of all ages and whatever their broader ways of living.

Influence of obesity on morbidity and mortality after acute myocardial infarction

The influence of being overweight or obese on hospital and late (1 year) mortality and reinfarction was studied in 1760 patients with acute myocardial infarction. Body mass index (BMI) was used to categorize patients as normal weight (BMI less than 25), overweight (BMI 25 to 30), and obese (BMI greater than 30). Clinical features and prognosis were compared in 658 normal weight patients, 884 overweight patients, and 218 obese patients. Complications during hospitalization and 1-year reinfarction rates following discharge were similar among the weight subsets. Hospital mortality was 13% in obese patients, similar to the 14% hospital mortality in normal weight patients, but significantly more than that in overweight patients (9%, p less than 0.05). When stratified according to age, 30% of obese patients greater than or equal to 65 years died in the hospital, compared to 13% of overweight patients (p less than 0.001), and 17% of normal weight patients (p less than 0.01). In patients less than 65 years, the obese group had a 6% mortality compared to a hospital mortality of 5% in overweight and 8% in normal weight groups (NS). In a multivariate analysis, obesity was an independent predictor of hospital death in the older, but not in the younger patient subset. One-year mortality for patients discharged from the hospital was significantly less in obese than in normal weight patients (7% vs 13%, p less than 0.05), but not different from the 11% mortality rate in overweight patients. Differences in mortality disappeared when patients were age stratified.(ABSTRACT TRUNCATED AT 250 WORDS)