Anthropometric, hormonal and biochemical differences in lean and obese women before and after menopause.

The menopausal status is associated with an increased risk of metabolic and cardiovascular diseases. Since the post-menopausal modifications have not been clearly investigated in obese women, we evaluated the influences of menopausal status on anthropometric, hormonal and biochemical characteristics in selected groups of normal-weight and obese women. We studied 92 female outpatients: 24 normal-weight pre-menopausal (Pre-NW) [body mass index (BMI) 23.6 +/- 0.48, age 44.8 +/- 0.68], 24 normal-weight post-menopausal (Post-NW) (BMI 23.7 +/- 0.44, age 55.5 +/- 0.69), 24 obese pre-menopausal (pre-OB) (BMI 32.3 +/- 0.45, age 44.6 +/- 0.75), 20 obese post-menopausal women (Post-OB) (BMI 32.9 +/- 0.57, age 55.2 +/- 0.82). All the subjects were non smokers and free from hypertension, diabetes or impaired glucose tolerance (IGT). Anthropometric parameters, body composition, 17 beta-estradiol, LH, FSH, androstenedione, SHBG, testosterone and leptin were determined. Free androgen index (FAI) and insulin resistance index (HOMA) were calculated. In comparison with Pre-OB, Post-OB had higher values of waist circumferences (p < 0.02), while Post-NW showed no difference. Total and LDL-cholesterol were high in Post-NW women, whereas in the obese subjects they were already elevated in the premenopausal period. SHBG levels declined and FAI increased in Post-OB in comparison with Pre-OB. SHBG levels showed an inverse correlation with BMI, waist and waist-to-hip ratio (WHR), while FAI positively correlated with waist values. Serum leptin levels were higher in Post-OB than in Pre-OB, whereas they were similar in normal-weight women. The rise of leptin levels may be related to the greater abdominal fat deposition. In addition, menopausal status of uncomplicated obese women is associated with a greater abdominal fat deposition and with higher values of free androgen index, which may be considered as factors of cardiovascular risk.

QT dispersion in uncomplicated human obesity.

OBJECTIVE: Because obese patients generally may be prone to ventricular arrhythmias, this study was designed to measure the interval between Q- and T-waves of the electrocardiogram (QT) interval dispersion (QTD) in uncomplicated overweight and obese patients. QTD is an electrocardiographic parameter whose prolongation is thought to be predictive of the possibility of sudden death caused by ventricular arrhythmias. To better evaluate the association between obesity per se and QTD, the study population was intentionally selected because they were free of complications. RESEARCH METHODS AND PROCEDURES: QTD (defined as the difference between the maximum and the minimum QT corrected interval [QTc] across the 12-lead electrocardiogram) was measured manually in 54 obese patients (Group A: mean body mass index [BMI] of 38.1 +/- 0.9 kg/m2 [SEM], 15 males and 39 females), 35 overweight patients (Group B: mean BMI of 27.3 +/- 0.2 kg/m2, 10 males and 25 females), and 57 normal weight healthy control subjects (Group C: mean BMI of 21.9 +/- 0.2 kg/m2, 17 males and 40 females). The obese and overweight patients had no heart disease, hypertension, diabetes, or impaired glucose tolerance and did not have any hormonal, hepatic, renal or electrolyte disorders. The study subjects were matched in terms of age (mean age 38.4 +/- 1.2 years) and sex. RESULTS: The QTDs were comparable among the three groups: Group A, 56.4 +/- 2.6 ms; Group B, 56.7 +/- 2.1 ms; and Group C, 59.4 +/- 2.1 ms; not significant. The QTc intervals of Group A and Group B were similar to that of Group C (411.8 +/- 3.3, 407.2 +/- 3.9, and 410.3 +/- 3.9 ms, respectively [not significant]) and did not correlate with BMI. An association was found between QTD and QTc (r = 0.24, p < 0.005). Using multivariate stepwise regression analysis of the study population, QTD did not correlate with age, BMI, waist circumference, or abdominal sagittal diameter. DISCUSSION: These data suggest that QTD in uncomplicated obese or overweight subjects is comparable with that in age- and sex-matched normal weight healthy controls. In this study population, no association was found between QTD and anthropometric parameters reflecting body fat distribution.

Food-related sensory stimuli are able to promote pancreatic polypeptide elevation without evident cephalic phase insulin secretion in human obesity.

The data concerning the cephalic phase of insulin secretion (CPIS) in human obesity are controversial. We investigated the effect of a variety of sensory challenges on CPIS in 17 non-diabetic obese patients (four males, 13 females, mean age 41.1 years, mean BMI 38.7). Water, saccharin, and lemon juice were used as oral stimuli, and a complete meal was simply presented as visual and olfactory stimulations. Twelve healthy normal-weight subjects (four men, eight women, mean age 39.9, mean BMI 22.5) also underwent oral stimulation as controls, and the patients who underwent the sight and smell stimulations were also tested for pancreatic polypeptide (PP) changes in order to verify the occurrence of truly cephalic reflex during the test. Insulin levels were measured before and after each stimulation (every min for the first 5 min, and then after 10, 20, and 30 min). None of the stimuli (saccharin, lemon juice or water retained in the mouth for 2 min and were then spat out; the combined and separate sight and smell of a meal for 2 min) led to a significant increase in insulin in the obese patients (except in the case of one woman after oral stimulation). The oral stimuli led to a variable CPIS in one female and three male controls. Despite the absence of CPIS, the five obese patients undergoing all three sensory stimulations related to the meal (combined sight and smell, sight alone and smell alone) showed an early and significant increase in plasma PP concentrations within the first 3 min; this was more pronounced after the combined than after the separate exposure. Although only preliminary, these results underline the variability but substantial lack of CPIS in obese patients, thus suggesting that it can be considered a relatively rare and unrelevant event even in the presence of a true brain-mediated reflex revealed by the rapid and consistent increase in PP found in our experiments.

The role of central fat distribution in coronary artery disease in obesity: comparison of nondiabetic obese, diabetic obese, and normal weight subjects.

OBJECTIVE: To investigate the degree of coronary artery disease (CAD) in relation to obesity and fat distribution in obese patients with normal glucose tolerance, in comparison with CAD of diabetic obese patients and of normal weight subjects with CAD. DESIGN: Patients listed for coronary angiography with different body mass index (BMI) with or without diabetes: study of the correlation between severity of coronary damage and fat distribution. SUBJECTS: 92 patients subdivided into: 30 normal glucose tolerant obese (BMI 31.7+/-0.5, aged 53+/-1.7 y), 28 type 2 diabetic obese (BMI 30.7+/-0. 3, aged 57+/-1.2 y), and 34 normal weight patients (BMI 23.1+/-0.3, aged 54+/-1.7 y). MEASUREMENTS: CAD assessed by angiography and evaluated according to the method of Gensini. Fat mass and fat distribution assessed by bioelectrical impedance and anthropometry. Clinical, biochemical and hormonal variables, as well as smoking habits and alcohol intake. RESULTS: The angiographic coronary scores were similar in nondiabetic obese and in diabetic obese patients, and were significantly higher than those of normal weight subjects. In the entire population coronary score correlated with indices of abdominal fat distribution. In the stepwise analysis of each group separately, waist hip ratio (WHR) correlated with coronary score only in normal weight nondiabetic patients. CAD was inversely associated with BMI only in nondiabetic obese patients. CONCLUSION: CAD of obese patients: 1) is similar to that of diabetic obese patients; 2) is more severe than that of normal weight individuals; and 3) is inversely correlated with BMI. CAD appears to be associated with WHR, not with BMI, only in nondiabetic patients with normal body weight. On the contrary, CAD of diabetic obese patients is unrelated to BMI and parameters of fat distribution, but is associated with smoking habits.

Diabetes and complications after cardiac surgery: comparison with a non-diabetic population.

Diabetes is a well-recognized independent risk factor for mortality due to coronary artery disease. When diabetic patients need cardiac surgery, either coronary-aortic by-pass (CABP) or valve operations (VO), the presence of diabetes represents an additional risk factor for these major surgical procedures. Because of controversial data on mortality rates and post-operative complications in diabetic patients, probably due to not exactly comparable groups of patients, this retrospective study aimed to compare two homogeneous populations, which were different only for the presence or absence of diabetes. We studied 700 patients undergoing cardiac surgery: 350 with and 350 without diabetes, mean age 62 +/- 9 years (67% males); 441 underwent CABP and 259 VO. Apart from the diabetes, the two groups were strictly matched for age, body mass index, concomitant pathologies and smoking habits, except for previous neurological injuries (more frequent in diabetic patients), and for a slightly lower ejection fraction in the diabetic group. Intra- and post-operative complications or events were evaluated carefully: death, number staying in post-operative intensive care unit (ICU), renal, hepatic and respiratory complications, necessity for reoperation and hemotransfusions. Anesthesia and surgical procedures (including extra-corporeal circulation techniques) remained substantially unchanged over the period of recruitment of patients (1996-1998) and applied equally to both groups of patients. All diabetic patients were treated with insulin by using standard procedures in order to optimize metabolic control. Diabetic patients in our study, did not show higher rates of mortality in comparison with non-diabetic patients, but had more total neurological complications, more renal complications, a higher re-opening rate, more prolonged ICU stay, and they needed more blood transfusions. Diabetes remains an independent risk factor for these events even in a multivariate logistic regression model analysis. In the subgroup of diabetic patients who underwent CABP a higher rate of renal dysfunction, re-opening, need for hemotransfusions and prolonged ICU stay were confirmed. In the subgroup of diabetic patients undergoing VO we found a higher rate of renal dysfunction, reopening, prolonged ICU stay and major lung complications. In conclusion, diabetes does not seem to increase the mortality rates of cardiac surgery, but diabetic patients undergoing CABP have, on the basis of the relative risk evaluation, a 5-fold risk for renal complications, a 3.5-fold risk for neurological dysfunction, a double risk of being hemotransfused, reoperated or being kept 3 or more days in the ICU in comparison with non-diabetic patients. Moreover, diabetic patients undergoing VO have a 5-fold risk of being affected by major lung complications.

Obesity and coronary artery surgery.

OBJECTIVE: To assess whether obesity is a risk factor for morbidity and mortality in patients undergoing elective coronary artery revascularization. DESIGN: Prospective, clinical study. SETTING: University hospital. PARTICIPANTS: Three hundred forty-five consecutive patients who underwent elective coronary revascularization with cardiopulmonary bypass and without associated procedures. INTERVENTIONS: Patients were assigned to the obese group if their body mass index was greater than 30 for men and 28.6 for women, according to the World Health Organization indications. MEASUREMENTS AND MAIN RESULTS: Preoperative and intraoperative variables were collected and checked for homogeneity of the groups. Postoperative outcome was assessed on the basis of intubation time, intensive care unit (ICU) and postoperative hospital stay, mortality rate, and incidence of transfusions, reoperations, low-output syndrome, minor and major neurologic dysfunction, minor and major lung dysfunctions, renal dysfunction, and superficial and deep infections. The effect of obesity on postoperative outcome was tested with a multivariate logistic regression analysis. Obese and control patients had the same intubation time and ICU and postoperative hospital stay. Mortality and all major complications occurred with the same incidence in the two groups. Obese patients had a significantly (p < 0.05) greater rate of superficial infections and more (24.1% v 7.4%; p < 0.001) minor lung complications. Conversely, they had a significantly lower transfusion rate (27.5% v42.7%; p < 0.01). CONCLUSION: Obese patients had only minor complications after coronary artery surgery. The large body surface area because of obesity protects them against the hemodilution-related transfusion risk.