Indices of relative weight and obesity

Body mass and acute myocardial infarction. GISSI-EFRIM Investigators

BACKGROUND

The relation between body mass index and acute myocardial infarction was analyzed using data from a multicentric case-control study conducted in Italy between September 1988 and June 1989 within the framework of the GISSI-2 trial.

METHODS

Subjects were 916 patients with acute myocardial infarction and no history of cardiovascular disease and 1,106 controls hospitalized for acute conditions not related to known or suspected risk factors for ischaemic heart disease.

RESULTS

Relative to the lowest quintile of the Quetelet Index (weight/height2) the estimated risks for subsequent quintiles were 1.2 (95% confidence intervals, (CI): 0.9 to 1.6), 1.7 (95% CI: 1.2 to 2.2), 1.8 (95% CI: 1.4 to 2.4), and 2.2 (95% CI: 1.7 to 3.0) when adjustment was made for age, sex, education, and smoking habits by means of logistic regression. The association was consistent across strata of sex, education, and smoking status, but not age. The estimated risk for subjects in the fifth quintile of the Quetelet Index relative to those in the first was 4.1 under 55 years of age, but only 1.7 between 55 and 64 years and 1.5 above age 65.

CONCLUSION

The relation between body mass and myocardial infarction was explained, at least in part, by higher serum cholesterol levels and the prevalence of diabetes and hypertension among fatter subjects. This does not, however, totally eclipse a possible causal relation between body mass and risk of myocardial infarction, since these conditions are a consequence, rather than a confounder, of overweight.

Gender, marital status and the social control of health behavior

Mortality rates are lower for married individuals than they are for unmarried individuals, and marriage seems to be even more beneficial to men than women in this regard. A theoretical model of social integration and social control is developed to explain why this may occur. Drawing from this model, I hypothesize that marriage may be beneficial to health because many spouses monitor and attempt to control their spouse's health behaviors. Furthermore, the provision, receipt, and consequences of these social control efforts may vary for men and women. These hypotheses are considered with analysis of a national panel survey conducted in 1986 (N = 3617) and 1989 (N = 2867). Results show that: (1) marriage is associated with receipt of substantially more efforts to control health for men than women, (2) those who attempt to control the health of others are more likely to be female than male, (3) there is some support for the social control and health behavior hypothesis among the married, and (4) the transition from married to unmarried status is associated with an increase in negative health behavior while the transition from unmarried to married status seems to have little effect on health behavior. A theoretical explanation is developed to explain these marital status differences.

Binge eating and weight concerns among young adults. Results from the Zurich cohort study

In the longitudinal cohort study of young adults from the Canton of Zurich in Switzerland, two groups of eating problems were defined: binge eating and weight concerns. Subjects with these conditions were interviewed at the ages of 27-28 and 29-30 years. The binge eaters, mostly women, differed both from subjects with weight concerns and from controls. They had more severe eating problems and more anxiety and depression. Follow-up as well as retrospective data suggest that eating problems are persistent for the binge eaters, and, to a lesser extent, also for subjects with weight concerns. Even so, professional treatment is rarely sought by subjects with eating problems. These findings encourage long-term studies on eating problems in community samples.

Fat distribution in overweight patients with Ullrich-Turner syndrome

Overweight patients with Ullrich-Turner syndrome (UTS) and control children with similar weight/height and indices of overweight were studied to clarify the unique fat distribution in the syndrome. Triceps and ulnar skin-fold thickness (SFT) in UTS patients was significantly less than that of obese children without the syndrome. The means of SFT at the subscapular and paraumbilical regions were also less in the patients than control girls, though significance was not documented. Thus, increased body weight in UTS children seems mainly to be due to excess of adipose tissue, not in the limbs but on the trunk, and/or due to the increment of lean body mass.

Adolescent smoking, weight changes, and binge-purge behavior: associations with secondary amenorrhea

BACKGROUND

The association of secondary amenorrhea with extreme forms of substance use, weight control, and exercise in nonrepresentative samples raises questions as to whether adolescents in the general population who engage in these behaviors are at increased risk for secondary amenorrhea. We examined the prevalence and behavioral correlates of secondary amenorrhea in a county-wide high school population of 2544 girls aged 13 to 18.

METHODS

A survey questionnaire, which elicited menstrual history as well as weight history, weight control practices, level of exercise, and use of cigarettes, wine, and beer, was administered during school hours; absentees were also surveyed. The completion rate was 91%.

RESULTS

The 1-year prevalence of secondary amenorrhea was 8.5%. Secondary amenorrhea was associated with smoking one or more packs of cigarettes per day (adjusted relative risk [RRa] = 1.96, 1.21-3.10), with multiple binge-eating behaviors in combination with laxative use or self-induced vomiting (RRa = 4.17, 2.54-6.32), and with weight fluctuation due to weight control (RRa = 2.59, 1.33-4.79). There was no association between amenorrhea and alcohol consumption or exercise level.

CONCLUSIONS

Estimates of attributable risk are provided and indicate that bulimic behaviors and cigarette smoking may result in a considerable excess of cases of secondary amenorrhea in an adolescent population.

Longitudinal study of gall stone prevalence at necropsy

A prospective study of the prevalence of gall stone disease at necropsy in a stable population has been undertaken over a 10 year period up to June 1988. In women, the prevalence of gall stone disease remained static but in men aged 50-59 years it rose from 7% (n = 148) in the first three years to 18% (n = 138) in the last three years (p less than 0.01) and in men aged 60-69 it rose from 12% (n = 370) to 20% (n = 366, p less than 0.01). In the latter age group the female: male ratio fell from 2:1 to 0.8:1. The proportion of deaths from coronary heart disease in men fell slightly in those over 70 during the study period. There was a fall in deaths from coronary heart disease in all age groups in women. Men with gall stones were less likely to have had a cholecystectomy than women, and overall 88% of gall stones remained in situ. In a parallel clinical study, the number of cholecystectomies carried out in the same district fell by 18% over the 10 years without any apparent change in the provision of resources. Cholecystectomy remained almost three times more frequent in women. National data indicate that there have been major changes in the average diet before and during the period of study in favour of reducing coronary heart disease. There has been no change in mortality from coronary heart disease in young men but if the observed increase in the prevalence of gall stones in men and the decrease in deaths from coronary heart disease in women are real phenomena, it seems likely that they are diet related.

The influence of obesity and underweightness on respiratory function of geriatric patients undergoing surgery

We investigated the influence of obesity and underweightness on the respiratory function of 228 patients over 65 ys. old undergoing elective surgery. The parameters we studied were preoperative Pa(O)(2) (Pa(O)(2)-pre), Pa(O)(2) under general anesthesia (Pa(O)(2)-op) and preoperative spirometric values including data from flow-volume curves and closing volumes. Triceps skinfold thickness (TSF), body mass index (BMI), Broca's index (BI) and Onodera's prognostic nutritional index (PNI) were measured or calculated. Respiratory parameters were compared between 3 groups; overweight (BMI >23), normal weight (BMI 20-22), underweight (BMI <19). Single and multiple correlations were analyzed between 3 nutritional parameters (BMI, TSF, PNI) and respiratory values. As a result, Pa(O)(2)-pre and Pa(O)(2)-op in overweight group were lower than those in the other groups. None of other parameters showed significant differences between the 3 groups. In multiple regression analysis, BMI correlated with Pa(O)(2)-pre (r = -0.24), Pa(O)(2)-op (r = -0.43), %VC (r = 0.18), peak flow rate (PFR, r = 0.17) and V(50)/HT (r = 0.18). TSF correlated with Pa(O)(2)-pre (r = -0.22), %MVV (r = -0.28) and RV/TLC (r = 0.28). PNI correlated with PFR (r = 0.23). We concluded that overweightness has greater influence on respiratory function of elderly patients than underweightness and that arterial blood gas analysis is essential in preoperative assessment of obese geriatric patients.

Molecular mapping of the mouse ob mutation

The mouse ob mutation has been mapped relative to a series of RFLPs among the progeny of three separate mouse crosses: an intraspecific backcross, an intraspecific intercross, and an interspecific intercross. Genotypic assignment at the ob locus was made by making use of measurements of body mass index and the plasma concentrations of glucose and insulin. These data have suggested that the development of diabetes in these animals is a consequence of unlinked polygenes. There was also evidence that unlinked Mus spretus alleles can diminish the obesity of ob/ob mice. From these data we have mapped several markers on chromosome 6 with the following order: cen-Cola-2-Met-ob-Cpa-Tcrb. The homologs of markers that flank ob map to human chromosome 7q, suggesting that if there is a human homologue of ob, it maps to 7q31.

Body composition and longevity: is there a longevous morphotype?

Life expectancies are increasing in populations throughout the world. As infectious diseases decline as causes of mortality, certain degenerative diseases including cardiovascular disease and cancer account for an increasing percentage of deaths. As more people survive into old age, the intrinsic limits on the human life span will be reached. It is clear that genetic factors have a strong influence on the life span. It is not clear, however, that there are identifiable longevous body types (morphotypes). For the first time in human history, large numbers of people 80 years old and older are available for study. If there is an association between body form and composition and superior longevity, it should be possible to identify its major aspects. Monitoring changes in body composition throughout the life cycle and the retention of reserves to be drawn upon when disease or trauma threaten life may provide the basis for prediction of the course of life threatening diseases. The unusually high survival of morphotypes classifiable as "moderately obese" casts doubt on standards recommending "ideal weights for height" if the criterion in question is survival.

Excess weight and precocious pubarche in children: alterations of the adrenocortical hormones

In this paper we assess the qualitative and quantitative differences in adrenal function before and after adrenocorticotropic hormone (ACTH) stimulation between normal weight and overweight precocious pubarche (PP) patients. Twelve of the 22 PP patients had a normal body weight for height with linear growth and bone ages (BAs) that were appropriate for chronological age. The remaining 10 PP patients had body weights which were greater than 120% of ideal weight for height and body mass indices (BMIs), which were more than 125% of the ideal for age and sex. In six overweight patients, linear growth was accelerated and BAs were advanced beyond chronological age. All patients underwent an ACTH stimulation test where they received an intravenous bolus of 250 micrograms Cortrosyn. Blood samples were obtained at 0' and 60' for 17-OHProgesterone (17-OHP), 17-OHPregnenolone (17-OHPG), dehydroepiandrosterone (DHEA), androstenedione (A-dione), and cortisol levels. Results of the baseline and stimulated adrenal hormones in the normal weight children were found to be within reference range for normal Tanner I children. In contrast, two of the 10 overweight children were suspected of having congenital adrenal hyperplasia [one with 21-hydroxylase (21-OHase) deficiency, another with 3-betahydroxysteroid (3 beta ol) deficiency]. These two children were indistinguishable in their linear growth rate and degree of skeletal maturation from the other overweight children. In both patients the BA/chronological age and BA/height age (HA) ratios were within two standard deviations of the mean for the overweight patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Eating disorder patient referrals from a population region 1977-1986

Three hundred and forty-three eating disorder patients (50% anorexia nervosa, 37% bulimia and 13% atypical eating disorder) were seen by the eating disorder service in the Wellington (New Zealand) region between 1977 and 1986. Ninety-six per cent were female. Annual rate of referral for anorexia nervosa remained stable at 5 per 100,000 population (34 per 100,000 females aged 15-29 years). Annual referral rate for bulimia increased from 6 to 44 per 100,000 females aged 15-29 years.

Overall survival of breast cancer patients in relation to preclinically determined total serum cholesterol, body mass index, height and cigarette smoking: a population-based study

Mean overall 5-year survival related to preclinically determined total serum cholesterol, body mass index (BMI), height and cigarette smoking has been analysed among 242 incident cases of breast cancer aged 36-63 years that developed in a population of 24,329 Norwegian women during a mean follow-up of 12 years (range 11-14). The study factors were ascertained at least 1 year prior to diagnosis (mean = 8 years), and the cases have been followed up with respect to death for a mean time of approximately 5 years after diagnosis. Patients whose preclinical total serum cholesterol values were within the highest quartile (greater than or equal to 7.52 mmol/l, mean = 8.58 mmol/l) of the underlying population had a hazard ratio of dying of 2.0 (95% confidence limits, 1.1 and 3.7) compared to cases with cholesterol values in the lowest quartile (mean = 5.28 mmol/l), after adjustment for age at diagnosis, clinical stage, and body mass index. In relation to BMI (Quetelet's index: weight/height2) patients who were obese prior to diagnosis were at higher risk of dying than those who were lean. Compared to patients in the lowest quartile of BMI (mean Quetelet = 21), the hazard ratio was 2.1 (95% confidence limits, 1.2 and 3.8) for patients in the highest quartile (mean Quetelet = 30), after adjustment for age at diagnosis, clinical stage, and total serum cholesterol. For height and for cigarette smoking, no relation with survival was observed. A potential problem of this study might be insufficient information about other well known prognostic factors, but the results suggest that preclinical total serum cholesterol and BMI are positively associated with the risk of dying among women who develop breast cancer.

A truncated species of apolipoprotein B (B67) in a kindred with familial hypobetalipoproteinemia

We describe a kindred in which the proband and 6 of his 12 children have hypobetalipoproteinemia. The plasma lipoproteins of the affected subjects contained a unique species of apolipoprotein (apo) B, apo B67, in addition to the normal species, apo B100 and apo B48. The size of apo B67 and immunochemical studies with a panel of apo B-specific antibodies indicated that apo B67 was a truncated species of apo B that contained approximately the amino-terminal 3,000-3,100 amino acids of apo B100. Sequencing of genomic apo B clones revealed that affected family members were heterozygous for a mutant apo B allele containing a single nucleotide deletion in exon 26 (cDNA nucleotide 9327). This frameshift mutation is predicted to result in the synthesis of a truncated apo B containing 3,040 amino acids. Apo B67 is present in low levels in the plasma but is easily detectable within the very low density lipoprotein and low density lipoprotein fractions. Examination of the proband's immediate family revealed seven normolipidemic subjects and seven subjects with hypobetalipoproteinemia. In the affected subjects, the mean total and low density lipoprotein cholesterol levels were 120 and 42 mg/dl, respectively. A significantly higher mean high density lipoprotein cholesterol level was found in the affected subjects (75 vs. 55 mg/dl). We hypothesize that the elevated high density lipoprotein cholesterol levels in subjects heterozygous for the apo B67 mutation may be metabolically linked to the low levels of apo B-containing lipoproteins in their plasma.

The clinical utility of maternal body mass index in pregnancy

To describe maternal body mass index and to compare the use of maternal weight and body mass index for risk assessment at the initial prenatal visit, 6270 gravid women who were consecutively delivered of infants were studied. Body mass index increased with advancing maternal age, parity, and advancing gestational age and was significantly greater in black women than in nonblack women. Risks for the development of adverse outcome associated with maternal obesity, including development of gestational diabetes, preeclampsia, fetal macrosomia, and shoulder dystocia, were comparably predicted by either maternal weight or body mass index greater than 90th percentile. Maternal weight was as predictive of preeclampsia, macrosomia, and shoulder dystocia as was body mass index when these factors were analyzed as continuous variables, whereas increasing body mass index was more predictive of gestational diabetes. The prediction of factors associated with low maternal weights, small-for-gestational-age birth, prematurity, low birth weight, and perinatal death was equivalent for maternal weight and body mass index that was less than 10th percentile. This study indicates that in the initial risk assessment of outcomes related to maternal weight, the calculation of maternal body mass index offers no advantage over simply weighing the patient. This finding contrasts with results in nonpregnant women.

Effect of alpha-adrenergic blockade on blood pressure, glucose, and lipid metabolism in hypertensive patients with non-insulin-dependent diabetes mellitus

To clarify the long-term effects of alpha-adrenergic blockade on blood pressure, glucose, and lipid metabolism, a selective alpha 1-adrenergic inhibitor (prazosin, 1.0 to 2.0 mg/day in divided doses) was administered as a single antihypertensive agent to 10 (four men and six women, aged 52 to 76 years) hypertensive patients (systolic blood pressure [SBP] greater than or equal to 150 mm Hg or diastolic blood pressure [DBP] greater than or equal to 90 mm Hg) with non-insulin-dependent diabetes mellitus (NIDDM) for up to 20 weeks. Blood pressure, glucose tolerance and immunoreactive insulin (IRI) response to 75 gm oral glucose load, hemoglobin A1 (Hb A1), serum lipid profile, and serum apolipoprotein were examined before and after treatment. SBP and DBP were significantly reduced at 20 weeks after treatment with the selective alpha 1-adrenergic inhibitor (SBP 167 +/- 6 mm Hg versus 152 +/- 7 mm Hg; DBP 81 +/- 3 mm Hg versus 76 +/- 3 mm Hg, (p less than 0.05 and p less than 0.01, respectively). Glucose tolerance and IRI response to glucose load were not significantly changed at 4 and 12 to 20 weeks after selective alpha 1-inhibitor treatment compared with the baseline data before treatment; the level of Hb A1 was not significantly changed at 4 and 20 weeks after treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Body mass index as a measure of body fatness: age- and sex-specific prediction formulas

In 1229 subjects, 521 males and 708 females, with a wide range in body mass index (BMI; 13.9-40.9 kg/m2), and an age range of 7-83 years, body composition was determined by densitometry and anthropometry. The relationship between densitometrically-determined body fat percentage (BF%) and BMI, taking age and sex (males = 1, females = 0) into account, was analysed. For children aged 15 years and younger, the relationship differed from that in adults, due to the height-related increase in BMI in children. In children the BF% could be predicted by the formula BF% = 1.51 x BMI-0.70 x age - 3.6 x sex + 1.4 (R2 0.38, SE of estimate (SEE) 4.4% BF%). In adults the prediction formula was: BF% = 1.20 x BMI + 0.23 x age - 10.8 x sex - 5.4 (R2 0.79, SEE = 4.1% BF%). Internal and external cross-validation of the prediction formulas showed that they gave valid estimates of body fat in males and females at all ages. In obese subjects however, the prediction formulas slightly overestimated the BF%. The prediction error is comparable to the prediction error obtained with other methods of estimating BF%, such as skinfold thickness measurements or bioelectrical impedance.

A prospective study of body mass, height, and smoking on the risk of colorectal cancer in women

Female registered nurses in the United States who responded to a questionnaire in 1976 that inquired about height, weight, and smoking history were followed for the development of colon or rectal cancers through May of 1984. Among the 118,404 respondents free of cancer in 1976, 191 colon cancers and 49 rectal cancers were observed during 916,170 person-years of follow-up. After omitting cases diagnosed within two years of weight report, we found little overall relation of body mass (Quetelet's) index to colon cancer risk; however there was a suggestion of elevated risk for the heaviest category of body mass index (greater than or equal to 29 kg/m2, relative risk (RR) = 1.5; 95 percent confidence interval = 0.8 - 2.7) relative to the lowest category (less than 21 kg/m2). Self-reported body mass index from adolescence had a slightly more pronounced, although not significant, association with risk of colon cancer. Increasing height was significantly associated with colon cancer (RR = 1.6, 95 percent confidence interval = 1.1 - 2.5 for the tallest category [greater than or equal to 168 cm] versus the shortest (less than 160 cm], trend, P = 0.04). Measures of current or past smoking failed to demonstrate any consistent relationship with colon cancer.

Target weight in children and adolescents with anorexia nervosa

Establishing realistic weight goals and their effective use in treatment is an integral part of management in anorexia nervosa. However, the processes involved are discussed rarely in the clinical and research literature. Various methods for setting target weights are reviewed, with consideration of the relative merits of their application in the treatment of pre-pubertal children and adolescents with anorexia nervosa.

Comparative effects of overweight on cardiovascular risk in younger versus older men

The relation of age and body mass index (BMI) to atherosclerosis risk factors was examined in 357 men. Older (greater than or equal to 45 years) men had higher (p less than 0.01) systolic and diastolic blood pressures, fasting cholesterol and glucose, and 1-hour glucose and insulin levels. Fasting insulin and triglyceride levels were not significantly different between the 2 age groups. Although older men (n = 170) had greater values for several risk factors, overweight (BMI greater than 25.5 kg/m2) increased risk factors more in men younger than 45 years (n = 187). In younger men, those with higher BMIs had a greater prevalence, respectively, of blood pressure greater than 140/90 mm Hg (35.2 vs 11.2%, p less than 0.0001), cholesterol greater than 200 mg/dl (53.5 vs 29.3%, p less than 0.001), fasting triglycerides greater than 150 mg/dl (38.0 vs 10.3%, p less than 0.0001), 1-hour glucose greater than 160 mg/dl (15.5 vs 5.2%, p less than 0.05), fasting insulin greater than 11 microU/ml (28.2 vs 5.2%, p less than 0.0001), and 1-hour insulin greater than 110 microU/ml (28.2 vs 9.5%, p less than 0.001). In contrast, among older men, the prevalence of elevated blood pressure, cholesterol, triglycerides and glucose values was not significantly greater in the subgroup with high BMI. However, elevations of fasting (19.6 vs 6.4%, p less than 0.05) and 1-hour insulin (29.3 vs 11.5%, p less than 0.01) values were more common among older men with higher BMIs.(ABSTRACT TRUNCATED AT 250 WORDS)

Obesity in children, adolescents and young adults

The prevalence of obesity in Finnish children, adolescents and young adults aged three to 24 years was estimated in three surveys performed within the multicentre project, "Cardiovascular Risk in Young Finns" (1980, 1983, 1986). Obesity was defined as either body mass index (weight/height) or skinfold thickness (triceps or subscapular) or both greater than 90th percentiles of age and sex-specific reference data for white children. Its mean prevalences among 9- to 18-year old boys and girls in three surveys (95% confidence limits) were 3.6% (3.1-4.2) and 2.1% (1.7-2.6) as estimated in terms of body mass index and triceps skinfold thickness or 4.3% (3.9-4.9) and 2.6% (2.2-3.1) according to body mass index and subscapular skinfold thickness. Thus the 9- to 18-year old boys were on average more often obese than the girls, but no statistically significant changes in the prevalence of obesity were observed over the period 1980-1986. Body mass index and triceps or subscapular skinfold thicknesses vary in sensitivity as indicators of obesity.

Acute effect of glipizide on glucose tolerance in obesity and diabetes mellitus (NIDDM)

The attempt has been made to identity the lowest dose of glipizide, a second generation sulphonylurea, capable of improving glucose tolerance in overweight and obese subjects with various degrees of glucose tolerance. Thirty one obese subjects, 12 with non insulin dependent diabetes mellitus (NIDDM), 9 with impaired glucose tolerance (IGT) and 10 with normal glucose tolerance (NGT) each underwent four OGTTS (75 g), at 1 week intervals, after administration in random order of placebo or glipizide 0.5, 1.0 or 2.5 mg 30 min before glucose. Glucose tolerance in all groups was progressively improved by the increasing doses of glipizide and was normalized by 1.0 mg glipizide in impaired glucose tolerance (IGT) and by 2.5 mg glipizide in NIDDM. Insulin release was not significantly affected by glipizide in the three groups of subjects. The data indicate that it is possible, at least in acute experiments, to improve glucose tolerance in overweight and obese subjects with IGT, with NGT and with NIDDM, with doses of glipizide that do not affect insulin release.

Treatment of anovulation due to polycystic ovarian syndrome by laparoscopic ovarian electrocautery

Our experience of ovarian electrocautery for the treatment of polycystic ovarian syndrome (PCOS) in ten women is described. We found that nine responded favourably, either ovulating spontaneously or becoming more responsive to ovulation induction. There was a significant and persistent fall in serum testosterone levels, and a transient fall with subsequent rise in inhibin. We recommend that laparoscopic ovarian electrocautery is considered as an alternative to ovulation induction with gonadotrophins, in women with PCOS who fail to respond to clomiphene citrate.

Use of relative weight and Body Mass Index for the determination of adiposity

Relative weight and Body Mass Index (BMI) are commonly used as measures of body fatness in epidemiologic and clinical studies. In order to determine their accuracy, they were compared to body fat measured by underwater weighting and total body water determination in 29 males and 75 females who varied widely in body composition. Relative weights calculated from the Metropolitan Life Insurance Tables correlated so highly with BMI that these measures can be considered to be identical (R2 = 0.992 to 0.999). Linear regression analysis showed a significant correlation between BMI and percentage body fat in men (R2 = 0.68, %fat = 0.99 X BMI -1.32, p less than 0.001) and women (R2 = 0.74, %fat = 0.94 X BMI + 10.77, p less than 0.001). We conclude that relative weight and BMI are nearly identical, and that they are reasonable estimates of body fatness.

Correlates of fasting insulin levels in young adults: the CARDIA study

Elevated fasting insulin is an independent risk factor for hyperlipidemia, hypertension, and cardiovascular disease, but determinants of insulin other than age and body mass remain poorly described. Potentially modifiable factors associated with insulin were identified by correlating anthropometric, dietary and physical activity data in the CARDIA cohort of 2643 black and 2472 white men and women aged 18-30 years. Insulin was positively correlated with serum glucose, body mass index (BMI), skinfold thickness, waist/hip ratio and sucrose intake, and negatively correlated with heavy physical activity score, treadmill exercise duration, and magnesium intake (each p less than 0.01). After adjustment for other covariates, the positive association of insulin with waist/hip ratio, skinfold thickness, and sucrose intake remained in the group as a whole, as did the negative associations with magnesium and treadmill duration. These relationships provide insight into potentially modifiable factors affecting insulin levels, and should be considered in interpreting associations between insulin levels and cardiovascular disease.

Extracellular space, blood volume, and the early dumping syndrome after total gastrectomy

Extracellular space and blood volume were measured using 82Br dilution and 51Cr-tagged erythrocytes in 24 tumor-free patients after total gastrectomy. Eleven of the patients suffered from early dumping. Age, blood volume, and extracellular space were significantly smaller in dumpers (P less than 0.05). The dumping score could be predicted by a multiple regression model considering blood volume per lean body mass and extracellular space (r = 0.637; P = 0.0039). Rapid (t1/2 less than 360 seconds) emptying of the gastric substitute, assessed using a 99Tc-labeled solid test meal, was significantly associated with dumping in addition to extracellular space and blood volume (r = 0.876; P = 0.0018). Both rapid emptying and a narrow extracellular space seem to contribute to the early dumping syndrome.

Population characteristics and cigarette yield as determinants of smoke exposure

Relationships of population characteristics, smoking history, and cigarette yield with smoke exposure as measured by peripheral blood concentrations of thiocyanate, carboxyhemoglobin, nicotine and cotinine were sought in 170 male smokers. This population of smokers had significant elevations of serum thiocyanate, blood carboxyhemoglobin and plasma nicotine and cotinine concentrations as compared with an equal number of age- and sex-matched nonsmokers and these concentrations correlated significantly with past 24-hour cigarette consumption. Although the nicotine yield of the cigarette correlated significantly with plasma cotinine and marginally with plasma nicotine, the reduction in plasma nicotine and cotinine was not proportionate to the reduced yield of the cigarettes, suggesting that smokers partially compensate for the lower yields of their cigarettes. Blood levels of carboxyhemoglobin, nicotine and cotinine were also significantly associated with the weight of the subjects, presumably due to the relationship between weight and the volume of distribution. Univariate and multiple regression analyses provided evidence that coffee and alcohol consumption and years smoked also may be important determinants of smoke exposure.

Ocular manifestations and impression cytology of anorexia nervosa

A prospective age- and sex-controlled study of seven anorexia nervosa patients and seven normal control patients was conducted to determine the ocular manifestations of anorexia nervosa. Slit-lamp examination of the anorexic patients demonstrated a high incidence (4/7) of multiple episcleral capillary aneurysms and subconjunctival hemorrhages. Two of seven anorexia nervosa patients had bilateral superficial punctate keratopathy. Anesthetized Schirmer tear testing demonstrated a significantly (P less than 0.005) reduced mean tear production in the anorexia nervosa group (11.3 mm) compared with the control group (22.4 mm). Masked interpretation of conjunctival impression cytology demonstrated moderate to severe conjunctival squamous metaplasia in the majority of the anorexia nervosa group (5/7) compared to normal conjunctival epithelium in the majority of the control group (5/7). Absence of nyctalopia, Bitot's spots, and xerosis, and lack of conjunctival goblet cell loss indicate that the anorexia nervosa group did not have vitamin A deficiency.

The overnight dexamethasone test is a worthwhile screening procedure

The overnight low-dose dexamethasone test is a convenient screening procedure for Cushing's syndrome. Claims that the test is associated with a high incidence of 'false positives', rendering it of little value particularly in obese and hospital in-patients, have been investigated in the present study. The data from 100 consecutive subjects undergoing overnight low-dose dexamethasone tests to examine for the possibility of Cushing's syndrome, were reviewed. Cushing's syndrome was identified in four patients, normal suppression of cortisol values occurred in 84 patients and 12 patients exhibited false positive results. Differences in body weights, body mass indices or in-patient status did not distinguish between those subjects with normal suppression of plasma cortisol and those subjects who yielded false positive results. These data indicate that the simple overnight dexamethasone test substituted for the more cumbersome traditional 48-h dexamethasone test in 84 of 96 patients who did not have Cushing's syndrome. Thus the overnight test provides a useful screening procedure but a small percentage of patients, approximately 12.5%, will require additional procedures to exclude Cushing's syndrome.

Properties and clinical implications of body mass indices

The properties of body mass indices were evaluated in a cross sectional study of the weights and heights of 5016 Chinese boys and girls aged between 3 and 18 years. Of the indices examined (weight/height (W/H), weight/height2 (W/H2), weight/height3 (W/H3) and weight/heightp (W/Hp], W/Hp was the only one that consistently showed least correlation with height, and so could be regarded as the optimal body mass index by the criterion of independence of the index from height. The exponent 'p' of W/Hp is, however, highly dependent on age; the value increases steadily between the age of 3 and 7-9 years, and then varies considerably around puberty. Only the age specific exponent ensures a lack of correlation between body mass index (W/Hp) and height. Age specific W/Hp should therefore be used in intrapopulation studies of weight or problems associated with obesity in children. Interpopulation comparison of weight and adiposity by W/H, W/H2, or W/H3 may give misleading results because of their dependence on height. Our results also suggest that the conventional weight for height charts may not be accurate enough for clinical use.

Body fat distribution and male/female differences in lipids and lipoproteins

The role of body fat distribution, as assessed by the ratio of waist-to-hip circumferences (WHR), in statistically explaining differences in levels of lipoproteins between men and women was studied using data collected in 1985-1986 from employed adults (mean age, 40 years). As compared with the 415 women, the 709 men had higher mean levels of triglycerides (+38 mg/dl) and apolipoprotein B (+11 mg/dl) as well as lower mean levels of high density lipoprotein (HDL) cholesterol (-15 mg/dl) and apolipoprotein A-I (-19 mg/dl). Additionally, men were more overweight, consumed more alcohol, and exercised more frequently than women but were less likely to smoke cigarettes. Controlling for these characteristics, however, did not alter the differences in lipoprotein levels between men and women. In contrast, adjustment for WHR (which was greater among men) reduced the sex differences in levels of apolipoprotein B (by 98%), triglycerides (by 94%), HDL cholesterol (by 33%), and apolipoprotein A-I (by 21%). Similar results were obtained using analysis of covariance, stratification, or matching; at comparable levels of WHR, differences in lipid and lipoprotein levels between men and women were greatly reduced. Although these results are based on cross-sectional analyses of employed adults and need to be replicated in other populations, the findings emphasize the relative importance of body fat distribution. Whereas generalized obesity and body fat distribution are associated with lipid levels, fat distribution (or a characteristic influencing fat patterning) can be an important determinant of sex differences in levels of triglycerides, HDL cholesterol, and apolipoproteins B and A-I.

Association of fasting insulin with blood pressure and lipids in young adults. The CARDIA study

The association of insulin with cardiovascular disease (CVD) may be mediated in part by the associations of insulin with CVD risk factors, particularly blood pressure and serum lipids. These associations were examined in 4576 black and white young adults in the CARDIA Study. Fasting insulin level was correlated in univariate analysis with systolic blood pressure (r = 0.16), diastolic blood pressure (r = 0.13), triglycerides (r = 0.27), total cholesterol (r = 0.10), high density lipoprotein (HDL) cholesterol (r = -0.25), and low density lipoprotein (LDL) cholesterol (r = 0.14), and with age, sex, race, glucose, body mass index, alcohol intake, cigarette use, physical activity, and treadmill duration (all p less than 0.0001). After adjustment for these covariates, insulin remained positively associated with blood pressure, triglycerides, total and LDL cholesterol, and apolipoprotein B and was negatively associated with HDL, HDL2 and HDL3 cholesterol, and apolipoprotein A-I in all four race-sex groups. Higher levels of fasting insulin are associated with unfavorable levels of CVD risk factors in young adults; these associations, though relatively small, can be expected to increase the risk of atherosclerosis. Demonstration of these relationships in a large, racially diverse, healthy population suggests that insulin may be an important intermediate risk factor for CVD in a broad segment of the U.S. population.

Increased volume and decreased emptying of the gallbladder in large (morbidly obese, tall normal, and muscular normal) people

Impaired gallbladder emptying has been suggested as a possible factor in the pathogenesis of gallstones. Obese people have an increased incidence of gallstones, but there is no evidence of this in nonobese large people. This study was undertaken to determine if abnormal gallbladder motility is present in obese people. Fasting gallbladder volumes were determined using real-time ultrasound in 18 morbidly obese subjects whose weights were in a steady state [45 kg (100 lb) over ideal weight or twice expected weight for age and height; 9 males, 9 females], 18 age- and sex-matched volunteers of average size, and 18 nonobese large normal males (9 tall, 9 muscular). Gallbladder emptying studies with 99mtechnetium-diisopropyliminodiacetic acid were performed using 200 ml of 10% cream as a stimulus. The small-volume liquid fatty meal contained 113indium-diethylenetriaminepentaacetic acid to control for differences in gastric emptying in obesity. The gallbladder emptying rate in large people, both obese and nonobese, was less than that in normals of average size (p = 0.05). Fasting gallbladder volumes in large people were: obese, 41 ml (37-66 ml) (median; 95% confidence limits); nonobese large normal, 40 ml (27-43 ml). These values were greater than in normals of average size [17 ml (14-21 ml) (p = 0.03)]. Postprandial gallbladder volumes were also greater in large people: obese, 15 ml (8-23 ml); nonobese large normal, 20 ml (13-23 ml) compared with 2 ml (1-5 ml) in normals of average size (p less than 0.05). There were no differences between obese and nonobese large people. There were no differences in gastric emptying rates or in cholecystokinin, gastrin, motilin, and secretin release between obese and normal subjects. Gallbladder volume is crudely proportional to body size. Although fasting and postprandial volumes are greater in obesity, this is also present in nonobese, relatively size-matched controls. These data do not support a role for impaired gallbladder emptying in gallstone formation in obese patients whose weights are in a steady state.

A prospective study of obesity and risk of coronary heart disease in women

We examined the incidence of nonfatal and fatal coronary heart disease in relation to obesity in a prospective cohort study of 115,886 U.S. women who were 30 to 55 years of age in 1976 and free of diagnosed coronary disease, stroke, and cancer. During eight years of follow-up (775,430 person-years), we identified 605 first coronary events, including 306 nonfatal myocardial infarctions, 83 deaths due to coronary heart disease, and 216 cases of confirmed angina pectoris. A higher Quetelet index (weight in kilograms divided by the square of the height in meters) was positively associated with the occurrence of each category of coronary heart disease. For increasing levels of current Quetelet index (less than 21, 21 to less than 23, 23 to less than 25, 25 to less than 29, and greater than or equal to 29), the relative risks of nonfatal myocardial infarction and fatal coronary heart disease combined, as adjusted for age and cigarette smoking, were 1.0, 1.3, 1.3, 1.8, and 3.3 (Mantel-extension chi for trend = 7.29; P less than 0.00001). As expected, control for a history of hypertension, diabetes mellitus, and hypercholesterolemia--conditions known to be biologic effects of obesity--attenuated the strength of the association. The current Quetelet index was a more important determinant of coronary risk than that at the age of 18; an intervening weight gain increased risk substantially. These prospective data emphasize the importance of obesity as a determinant of coronary heart disease in women. After control for cigarette smoking, which is essential to assess the true effects of obesity, even mild-to-moderate overweight increased the risk of coronary disease in middle-aged women.

Anthropometric variables and risk of breast cancer

The role of anthropometric variables in the risk of breast cancer has been investigated using pooled data from 2 hospital-based case-control studies conducted in Italy for a total data-set of 3,247 cases and 3,263 controls. No association was observed in pre-menopausal women between breast cancer risk and height, weight, indices of body mass (W/H2; W/H1.5) and surface area. In post-menopausal women, the risk of breast cancer was inversely related to height, being 0.8 in taller women (greater than 165 cm) compared with women 155 cm tall or less; the trend in risk, although not constantly decreasing, was statistically significant (p trend = 0.03). A direct, statistically significant association emerged with weight and indices of body mass and post-menopausal breast cancer risk. Considering 2 indices of body weight (W/H2 and W/H1.5) and relative to thinner women, the respective estimated risks of post-menopausal breast cancer increased to 1.4 and 1.3 for grossly obese women, and the corresponding p values for trend were respectively 0.002 and 0.02. The role of overweight was more evident in women with early age at menopause, thus suggesting a duration-risk effect.

Body mass index and risk of breast cancer. A prospective study of 23,826 Norwegian women

The association between body mass index (BMI) and the incidence rate of breast cancer has been examined in 236 cases of breast cancer that developed among 23,826 Norwegian women during 11 to 14 years of follow-up. At the time of height and weight measurement they were 35 to 51 years of age, and at the end of follow-up their age was between 46 and 63 years. There was an overall age-adjusted incidence rate ratio (IRR) of 0.52 (95% confidence limits, 0.34 and 0.77) for women in the highest quartile of BMI compared to women in the lowest quartile, which was confined to an effect observed among women who were diagnosed at age 50 or earlier (IRR = 0.36). The association with BMI displayed an inverse dose-related trend (chi 2 for trend = 14.22, p less than 0.001). The negative trend was particularly pronounced among non-smoking women (chi 2 = 14.63), and no clear trend associate with BMI was observed among women who smoked 10 or more cigarettes per day (chi 2 = 0.41), indicating an interaction between BMI and cigarette smoking (chi 2 interaction = 3.86, p = 0.05). We thus suggest that there is a negative association between body mass index and risk of breast cancer among premenopausal women.

Adjuvant chemohormonal therapy with cyclophosphamide, methotrexate, 5-fluorouracil, and prednisone (CMFP) or CMFP plus tamoxifen compared with CMF for premenopausal breast cancer patients. An Eastern Cooperative Oncology Group trial

The current trial was designed to assess whether the addition of prednisone or prednisone + tamoxifen would enhance the therapeutic effectiveness of 1 year of adjuvant CMF therapy. Premenopausal women with ipsilateral axillary node-positive breast carcinoma and known estrogen receptor (ER) status were randomized to receive 1 year of postoperative treatment with 12 28-day cycles of cyclophosphamide, methotrexate, 5-fluorouracil (CMF), CMF plus prednisone (CMFP), or CMFP plus tamoxifen (CMFPT). There were 553 analyzed cases with 188 receiving CMF, 183 CMFP, and 182 CMFPT. The overall time to relapse (TTR) and survival comparisons between the regimens are not statistically different at a median follow-up time of 7.7 years. The major subgroups currently with a suggestive TTR difference are greater than 3N+ (CMFPT greater than CMF, P = 0.07) and estrogen receptor-negative (ER-) greater than 3N+ (CMFPT greater than CMF, P = 0.03). Patients receiving CMFPT appeared to have a superior survival to CMF in the ER- greater than 3N+ cohort (P = 0.02). The following patient characteristics were associated with a significantly longer TTR: decreasing nodal involvement or tumor size, positive ER status, age greater than or equal to 40 years, and decreasing obesity. The favorable effects of decreasing nodal involvement, positive ER status, age 40 years or greater, and decreasing obesity carried over to survival. Development of amenorrhea was also significantly associated with improved survival (P = 0.001). Toxicity was increased by the addition of prednisone to CMF and by the addition of tamoxifen to CMFP. Overall relapse patterns were similar among the three regimens. The results of the current trial do not currently suggest an overall therapeutic benefit for adding prednisone or only 1 year of tamoxifen to CMF adjuvant treatment.

Simple estimation of ideal body weight from body mass index with the lowest morbidity

Body mass index (BMI) is expressed by the body weight (kg) divided by height (m) squared. Therefore, if we know ideal BMI, ideal body weight (kg) of each individual can be calculated by a formula: Ideal BMI x height (m)2. In order to estimate ideal BMI, we investigated average BMI with the lowest morbidity using 4565 Japanese men and women aged 30 to 59 years. Their BMI distributed widely with the highest frequency at 23 in men and 21 in women. The morbidity was evaluated by the number of medical problems that the subjects with each BMI have. The BMI associated with the lowest morbidity was calculated to be 22.2 kg/m2 in men and 21.9 kg/m2 in women according to the quadratic regression curves derived from the relation between BMI and morbidity. From these data, we propose that an ideal body weight in Japanese is 22 x height (m)2.

Identification of high risk groups for breast cancer by means of logistic models

In order to identify high risk groups for breast cancer, unconditional multiple logistic regression models based on 5 widely recognized and easily identifiable risk factors (age at menarche, at menopause and at first birth, family history of breast cancer and body mass index) were applied to a large dataset including 2085 cases and 1936 controls aged 50 or over derived from two unmatched hospital-based case-control studies conducted in Italy. Although various models provided an excellent fitting, both on the whole dataset and using a training-testing approach to a priori identified separate subset, the observed extent of variation in breast cancer risk between highest and lowest decile of the distribution was limited to a factor 2. This indicates that the 5 variables considered did not allow identification of subgroups with substantially elevated risk of breast cancer to have practical implications for screening/prophylactic treatment purposes.

The significance of the ratio of body weight/height as a practical obesity index and the changes in the values in Japanese adults

1. It was observed that the W/H ratio highly correlated with body weight, while it had low correlation with age and height. From this fact, the W/H ratio was considered to have a practical value as an index from which adult obesity can be more easily judged than from BMI. 2. The W/H ratios of Japanese adults continue to increase in men of all age groups and women in the 50 or older age groups. That is, people tend towards obesity with age. Thus this fact may be associated with the increase in incidence of adult diseases in Japan.

Self-perceived health among sports participants and non-sports participants

This paper examines and compares the self-perceived health (SPH) of a sample of sports participants (n = 1385) and a matched sample of non-participants (n = 292). Ratings of health were generally found to be favourable among both samples, but a non-parametric analysis of their distributions revealed that the SPH of sports participants was significantly (P less than 0.0001) better than that of the non-participants. SPH improved with age among both samples, but above the age of 34, the non-participants' perceived health ceased to be inferior to that of participants. Controlling for age and gender revealed no difference in SPH above 24 years among males and 34 years among females. SPH was related to a variety of additional health-related factors. Multiple regression analysis was used to identify the predictors of SPH for both samples, and highlighted marked differences between them in the type and number of contributory factors. It is suggested that participation in active sports may enhance health awareness, especially among the young, and that future studies of this kind among sports populations should take account of the levels of commitment (frequency, duration and intensity) to sport.