[What do we know about obesity?]. / Cosa sapere sul problema obesità?

The prevalence of obesity is increasing rapidly in most industrialized countries and it is known that obesity is associated with increased risk of cardiovascular morbidity and mortality. Commonly, obesity is defined by the Body Mass Index (BMI). However, BMI fails to consider body fat distribution. The relationship between the risk of metabolic-cardiovascular diseases and body fat distribution indices, rather than measures of the degree of body fatness as expressed by BMI, has long been recognized. Clinical and epidemiological research has found waist circumference to be the best anthropometric indicator of both total body fat and intra-abdominal fat mass. Android obesity is associated with metabolic syndrome and increased cardiovascular risk through molecular mechanisms possibly linking the metabolic syndrome to hemostatic and vascular abnormalities. Obesity guidelines suggest the need for weight reduction using behavioural change to reduce caloric intake and increasing physical activity. A realistic goal for weight reduction is to reduce body weight by 5% to 10% over a period of 6 to 12 months. Combined intervention of a low calories diet, increased physical activity, and behaviour therapy provides better outcomes for long-term weight reduction and weight maintenance than programs that use only one or two of these modalities. The anorexiant drugs affect neurotransmitters in the brain. The sibutramine has norepinephrine and serotonin effects. Orlistat has a different mechanism of action: the reduction of fat absorption. Recently, the blockade of the endocannabinoid system with rimonabant may be a promising new strategy.

Association between circulating adiponectin and interleukin-10 levels in android obesity: effects of weight loss.

OBJECTIVE: Adiponectin inhibits vascular inflammation and increases IL-10 mRNA expression in human macrophages. Thus, we investigated the possible relationship between plasma adiponectin and IL-10 levels and the effects of a diet-induced moderate weight loss on both cytokines. PATIENTS AND STUDY DESIGN: Plasma adiponectin and IL-10 levels were analyzed in 64 android [body mass index (BMI), > 28 kg/m2; waist to hip ratio (WHR), > or = 0.86] and 20 gynoid [BMI, > 28 kg/m2; WHR, < 0.86] obese healthy women. Android obese women (49 +/- 14 yr) had a mean BMI of 37.1 +/- 5.3 kg/m2, similar to that of gynoid obese women (49 +/- 11 yr; BMI, 33.4 +/- 2.6 kg/m2). Twenty nonobese control women (46 +/- 11 yr; BMI, 25.2 +/- 2.2 kg/m2) were also studied. In 15 android obese women, measurements were repeated after a 12-wk diet period (1200 kcal/d). RESULTS: Median adiponectin [5.2 (range, 3.3-7.8) vs. 12.1 (9.7-13.9) vs. 15.0 (12.6-18.2) microg/ml; P < 0.0001] and IL-10 [1.8 (1.2-3.3) vs. 3.5 (2.9-4.3) and vs. 4.1 (3.5-4.8) pg/ml; P < 0.0001] levels were lower in android vs. gynoid vs. nonobese women. Among android obese women, low adiponectin levels were independently related (P < 0.0001) to decreased IL-10 levels, independently of BMI, WHR, or insulin resistance. No significant change in either median adiponectin or IL-10 levels was observed after body weight reduction (8 +/- 4 kg; P < 0.01), although percent changes in adiponectin paralleled those in IL-10 (P < 0.05). CONCLUSIONS: Android obesity is associated with a concomitant reduction of IL-10 and adiponectin levels. However, the antiinflammatory status of obesity might require prolonged periods of energy-restricted diets to revert to normal.

Leptin increase is associated with markers of the hemostatic system in obese healthy women.

BACKGROUND: Leptin, a hormone secreted by the adipose tissue, might be a link between obesity and increased morbidity for cardiovascular disease. Leptin exerts proinflammatory, pro-angiogenic actions by activating a specific receptor (Ob-Rb) which is expressed in human endothelial cells. Thus, a link may exist between leptin expression and endothelial dysfunction. OBJECTIVES: We sought to determine whether in obese women there is a correlation between leptin levels, endothelial perturbation and coagulative activation. METHODS: Circulating levels of leptin, von Willebrand Factor (VWF), factor (F)VIIa, prothrombin fragment 1 + 2 (F1+2), were measured in 51 non-diabetic, obese women and in 51 normal-weight subjects, using immunoenzymatic assays. RESULTS: Obese women had significantly higher levels of leptin, VWF, FVIIa, F1+2 compared with healthy women. Simple correlation coefficients showed significant correlation between leptin and either VWF, FVIIa, or F1+2 concentrations. A multiple linear regression analysis, performed to quantify further the relationship between leptin levels and the above-mentioned variables as well as the inflammatory marker C-reactive protein (CRP) and including age, body mass index (BMI), waist-hip ratio (WHR) and lipid parameters as potential confounders, revealed that only FVIIa and VWF were independently related to leptin levels. Reduction in adipose tissue after weight loss resulted in a decrease in both circulating leptin and endothelial and coagulative activation markers. CONCLUSIONS: We suggest that leptin might have pro-atherogenic effects in vivo, with a mechanism involving endothelial cell activation.

Large waist circumference and risk of hypertension.

OBJECTIVE: To examine the relationship between 24 h ambulatory blood pressure monitoring and three commonest anthropometric measurements for obesity--body mass index (BMI), waist-to-hip ratio (WHR) and waist circumference (W). DESIGN: Cross-sectional survey among outpatients at the Obesity Research Center. SUBJECTS AND METHODS: Four-hundred and sixty-one overweight or obese subjects, non-diabetic, otherwise healthy, aged 20-70 y, of either sex, were consecutively recruited. All subjects underwent 24 h ambulatory blood pressure monitoring. The population study was separated in normotensive and hypertensive males and females and the possible risk factors for hypertension (W, WHR, BMI and age) were subdivided into different classes of values. RESULTS: Logistic regression shows that W is the most important anthropometric factor associated with the hypertensive risk. Among males with W> or =102 cm the odds ratio (OR) for hypertension is three times that of males with W<94 cm using casual BP measure (OR 3.04), nearly four times higher using 24 h BP mean (OR 3.97), and even five times higher using day-time BP mean (OR 5.19). Females with W> or =88 cm have a risk for hypertension twice that of females with W<80 cm, whatever BP measurement was take (casual, 24 h or day-time). Males with WHR> or =0.96 and females with WHR> or =0.86 show significant OR for hypertension only by 24 h BP measurement and by day-time BP measurement. BMI seems to have no significant relationship to hypertensive risk. Age shows a significant relationship to hypertensive risk only considering males aged > or =55 y and females aged > or =50 y. CONCLUSION: The waist circumference seems to have a strong association with the risk of hypertension, principally by the ambulatory BP monitoring, when compared with casual BP measurement.

Clinical nutrition: inadequate teaching in medical schools.

BACKGROUND AND AIM: The teaching of Clinical Nutrition (CN) is frequently neglected in Medical Schools, though many official institutions strongly recommend its incorporation in their curricula. This work aimed to assess CN knowledge among final-year medical students and final-year dietology diploma students. METHODS AND RESULTS: We compared the performances of final-year Medical School students who did and who did not take the CN course and final-year dietology students in a computer-based multiple choice question examination related to core CN competencies that primary-care physicians and dieticians should know and be able to put into practice. The medical students who did not take the CN course correctly answered significantly fewer questions compared with those who did and the dietology students (both p < 0.001). There was also a difference in the percentages of who passed the test: students who did not take the course: those 18%; those who did: 77%; dietology students: 76% (p < 0.001). CONCLUSIONS: There are numerous barriers to the incorporation of nutrition in Medical School curricula. The medical school students may have achieved poorer results because dietology students followed nutrition education programs later in their curriculum. Our Medical School has therefore included CN education as part of its internal medicine course since 1998.

Non insulin-dependent diabetes mellitus (type 2) secondary failure. Metformin-glibenclamide treatment.

The goal of sulphonylurea (S) treatment in Non-Insulin-Dependent Diabetes Mellitus (NIDDM - type 2 diabetes) subjects should be to obtain a satisfactory glycemic control (fasting glycemic levels < 140 mg%). The loss of an adequate blood glucose control after an initial variable period of S is known as secondary failure (SF). The number of SF are extremely variable among different trials for many reasons, some of which are patient-related: increased food intake, weight gain, non-compliance, poor physical activity, stress, diseases and÷or impaired pancreatic beta cell function, desensitization after S chronic therapy, reduced absorption, concomitant therapies. Many therapeutic strategies have been proposed to achieve an adequate metabolic control in type 2 diabetes patients: switch to intensive insulin therapy and subsequent return to S therapy; association with insulin; association with sulphonylureas plus biguanides. The association biguanides and S, in particular glibenclamide plus metformin, is now widely used by diabetologists in SF since glibenclamide improves insulin secretion while metformin exerts its antidiabetic.

Risk factors for hypertension in obese women. The role of weight cycling.

OBJECTIVE: To study significant factors associated with the risk of hypertension among obese women, with and without a history of weight cycling (WC). DESIGN: Case-control study. SETTING: Obesity Clinic of Chieti University, Italy. SUBJECTS: A group of 258 obese women aged 25-64 y (103 cases with hypertension and 155 controls) were recruited. All obese subjects had the same clinical characteristics, were without a family history for hypertension, were non-smokers, had normal lipidemic profiles and normal glucose tolerance, were not taking any medication and were otherwise healthy. INTERVENTION: In the weight cycling women, the history of WC was established on the basis of at least five weight losses in the previous 5 y due to dieting, with a weight loss of at least 4.5 kg per cycle. A logistic regression model adjusted for confounding variables such as waist-to-hip ratio (WHR) and weight cycling history parameters was used and the odds ratio (OR) with 95% confidence intervals was calculated. RESULTS: The risk of hypertension increases in subjects with larger WHR (OR 7.8; 95% CI 3.4-17.9) and with a positive history for WC (OR 4.1; 95% CI 2.4-6.9). Further, in obese patients with WC, the weight cycling index and the sum of the weight regained are also important risk factors for hypertension. CONCLUSIONS: These findings could support the hypothesis that it is the combined exposure of central-type obesity and WC that strongly raises the risk of hypertension. SPONSORSHIP: This work has been financially supported by a grant of Ministero dell'Università e della Ricerca Scientifica e Tecnologica.