Relation of body fatness and its distribution to cardiovascular risk factors in young blacks and whites. The role of insulin

Persons whose body fat is distributed predominantly in the abdomen compared with the hips are at increased risk of several chronic diseases. This study examined the cross-sectional relation of percent body fat, computed from skinfold thickness, and fat distribution, measured by the waist-to-hip girth ratio, to physiologic cardiovascular risk factors in a biracial sample (blacks and whites) of young adults aged 18-30 years. The subjects were persons who were examined at baseline (1984-1986) in the Coronary Artery Risk Development in Young Adults Study in four US metropolitan areas. The two hypotheses tested were that 1) after adjusting for percent body fat, waist-to-hip girth ratio is associated with several physiologic risk factors, and 2) fasting concentrations of serum insulin partly explain such association. Percent body fat was significantly associated with all measured blood lipids, lipoproteins, apolipoproteins, uric acid, and blood pressure. Waist-to-hip girth ratio was significantly, although more weakly, associated in multivariate models with blood concentrations of triglycerides, high density lipoprotein (HDL) cholesterol, HDL2 cholesterol, apolipoproteins A-I and B, low density lipoprotein cholesterol (in women only), uric acid, and systolic blood pressure, but was not associated in either sex with total cholesterol, HDL3 cholesterol, or diastolic blood pressure. Fasting serum insulin concentrations were significantly associated with percent body fat (Pearson r = 0.45-0.53), waist-to-hip girth ratio (Pearson r = 0.18-0.27), and most of the physiologic risk factors. Inclusion of fasting insulin in multivariate models reduced, but rarely eliminated, associations between waist-to-hip girth ratio and the physiologic risk factors. These findings suggest that obese young adults, especially those with abdominal fat preponderance, carry a physiologic profile that places them at higher risk of cardiovascular disease, and that fasting insulin concentrations are only partly explanatory.     

Increased incidence of diabetes mellitus in relation to abdominal adiposity in older women

The relationship between body fat distribution, measured by the ratio of waist-to-hip circumferences (WHR), and the 2 year incidence of diabetes mellitus was examined in a cohort of 41,837 women aged 55-69 years. The 399 women who reported the new onset of diabetes had a significantly greater mean body mass index (kg/m2) and WHR than non-cases. After adjustment for body mass index (BMI), age and education level using multivariate logistic regression, WHR was a significant independent predictor of diabetes in a dose-response fashion. Cases were 4.6 times (95% CI = 3.8, 5.6) more likely than non-cases to be in the upper tertile of WHR and 2.2 times (95% CI = 1.8, 2.7) more likely to be in the middle tertile. Women in the highest tertiles of both WHR and BMI had a 14.4-fold (95% CI = 9.5, 21.9) higher risk of diabetes than women in the lowest tertiles. These results demonstrate that increased abdominal adiposity is a significant independent risk factor for the development of diabetes mellitus in older women.     

Peptic ulcer and gastric carcinoma: diagnosis with biphasic radiography compared with fiberoptic endoscopy

The diagnostic value of biphasic radiographic examination of the stomach and duodenum was compared with that of fiberoptic endoscopy in a prospective, blinded study of 385 patients with dyspepsia. This investigation was directed at gastric malignancies and peptic ulcers. Methodologically there is no absolute standard for a study of this kind because histologic examination is useful for detection of cancer but inadequate for ulcers. As an alternative, kappa indexes and the sensitivity and specificity, as derived by Hui and Walter, were calculated and compared. For the detection of gastric carcinoma, radiographic and endoscopic findings had almost perfect agreement beyond chance. For gastric ulcers, radiography and endoscopy had substantial agreement, which became perfect if small ulcers (less than 5 mm) were excluded. For duodenal ulcers, radiography had a lower sensitivity than endoscopy; this disagreement disappeared if small ulcers were excluded. Both methods have equal merit; choice of the initial diagnostic procedure will therefore depend on cost, discomfort to the patient, and risk of complications.     

Induction of synaptic extracellular matrix molecules at ectopic neuromuscular junctions

The induction of synapse-specific molecules recognized by peanut agglutinin (PNA) was examined at ectopic neuromuscular junctions in adult frog muscles using light and electron microscopy. In normal frog muscles, PNA specifically recognizes the extracellular matrix at neuromuscular junctions but not at extrajunctional regions. This report shows binding of PNA at ectopic neuromuscular junctions which were initially extrasynaptic and hence unrecognized by PNA. Results suggest that synapse-specific extracellular matrix molecules can be induced de novo at new junctional sites.     

Prevalence and accuracy of home sphygmomanometers in an urban population.

The prevalence of ownership (7.5 per cent) and the accuracy of home sphygmomanometers were determined in a population-based survey in the Minneapolis-St. Paul metropolitan area. Sixty-four per cent of home sphygmomanometers were accurate within +/- 2 mm Hg of a calibrating sphygmomanometer; another 26 per cent were within +/- 3-6 mm Hg. These results suggest that although many home sphygmomanometers are accurate, some are very inaccurate. Health care providers should advise regular calibration when home sphygmomanometers are used for therapeutic self-management of hypertension.     

Arterial distensibility and physical activity in the ARIC study.

PURPOSE: Arterial distensibility decreases with age. This decrease may be associated with the initiation and/or progression of hypertension and atherosclerosis and may be attenuated by positive lifestyle habits, including habitual physical activity. We tested the hypothesis that self-reported sport, leisure, and work physical activity is associated with greater arterial distensibility (i.e., carotid artery pulsatile diameter changes). METHODS: The Atherosclerosis Risk in Communities (ARIC) study assessed left common carotid arterial diameters and intimal-medial wall thickness (IMT) using B-mode ultrasound techniques, in 10,644 African-American and white men and women aged 45-64 yr and free of cardiovascular disease. RESULTS: Work activity, but not sports or leisure activity, was weakly associated with greater arterial distensibility in an ANCOVA model adjusted for blood pressure and other covariates (diastolic arterial diameter, pulse pressure, pulse pressure squared, age, race, sex, smoking, dietary fat intake, height, education, and clinical center) (P for linear trend = 0.03). Vigorous sports activity was weakly positively associated with arterial distensibility (arterial diameter change (mean +/- SE in mm) 0.42 +/- 0.004 vs 0.41 +/- 0.002 for the 12.7% of participants reporting any vs no vigorous activity, P = 0.02), and this association was not attenuated by adjustment for IMT, body mass index, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, or diabetes. Repeated analyses with traditional arterial stiffness indices showed similar findings for vigorous but not work activity. CONCLUSION: In contrast to several smaller studies, these findings do not support the hypothesis that habitual physical activity has a strong, consistent positive effect on arterial distensibility.     

Ectopic ureter and ureterocele: their varied sonographic manifestations

The sonographic examinations of four patients with simple ectopic ureters and 11 with ectopic ureteroceles were reviewed to determine distinguishing characteristics. Ectopic ureters, in cases of extreme dilatation and tortuosity, sometimes mimic multiseptated, cystic abdominal masses. However, the proximal portions of some severely dilated ureters are surprisingly small. Ectopic ureters sometimes indent the lower vesical wall, simulating a ureterocele. Ectopic ureteroceles are dynamic structures, changing in shape and size according to intravesical pressure. The lower pole of a duplex kidney may be difficult to detect because of displacement by the dilated upper renal pelvis and ureter. The renal parenchyma associated with an ectopic ureter may be equally difficult or impossible to find because of diminutive dysplasia or, less commonly, acquired atrophy. Dysplasia is characterized sonographically by highly echogenic parenchyma, lack of corticomedullary differentiation, and occasionally massive enlargement by cysts. Ectopic ureters and ureteroceles can be identified by fetal sonography.     

Fibrinolytic factors and atherothrombotic events: epidemiological evidence

The fibrinolytic system is important in thrombus resolution at the site of atherosclerotic plaque rupture. The usual levels of plasma fibrinolytic factors have been hypothesized to be important in predicting atherothrombotic events. In this report, prospective clinical, prospective epidemiological, and genetic epidemiological studies of fibrinolytic factors and incident cardiovascular disease are reviewed. Many prospective studies have reported an unadjusted positive association between plasma fibrinolytic markers (eg, tissue plasminogen activator antigen or plasminogen activator inhibitor antigen) and risk of cardiovascular disease. The association tends to be strong and demonstrate a dose-response, but often becomes statistically nonsignificant after adjustment for other risk factors. About half of the genetic epidemiological studies suggest that a polymorphism of a gene coding for fibrinolysis may be associated with cardiovascular disease, but that the relative risk is modest, at best. Thus, epidemiological evidence to date is inconclusive about whether impaired fibrinolysis may be a 'cause' of atherothrombotic events. In fact, alterations of plasma fibrinolytic factors might be a 'consequence' of atherosclerosis. At present, it seems premature to recommend routine measurement of fibrinolytic factors to identify patients at risk of cardiovascular disease events. Some directions for future research on this topic are offered.     

Treatment of compulsive behaviour in eating disorders with intermittent ketamine infusions

We have previously shown that eating disorders are a compulsive behaviour disease, characterized by frequent recall of anorexic thoughts. Evidence suggests that memory is a neocortical neuronal network, excitation of which involves the hippocampus, with recall occurring by re-excitement of the same specific network. Excitement of the hippocampus by glutamate-NMDA receptors, leading to long-term potentiation (LTP), can be blocked by ketamine. Continuous block of LTP prevents new memory formation but does not affect previous memories. Opioid antagonists prevent loss of consciousness with ketamine but do not prevent the block of LTP. We used infusions of 20 mg per hour ketamine for 10 h with 20 mg twice daily nalmefene as opioid antagonist to treat 15 patients with a long history of eating disorder, all of whom were chronic and resistant to several other forms of treatment. Nine (responders) showed prolonged remission when treated with two to nine ketamine infusions at intervals of 5 days to 3 weeks. Clinical response was associated with a significant decrease in Compulsion score: before ketamine, mean +/- SE was 44.0 +/- 2.5; after ketamine, 27.0 +/- 3.5 (t test, p = 0.0016). In six patients (non-responders) the score was: before ketamine, 42.8 +/- 3.7; after ketamine, 44.8 +/- 3.1. There was no significant response to at least five ketamine treatments, perhaps because the compulsive drive was re-established too soon after the infusion, or because the dose of opioid antagonist, nalmefene, was too low.