Android obesity is associated with enhanced lipid peroxidation and persistent platelet activation. These abnormalities are driven by inflammatory triggers related to the degree of abdominal adiposity and are, at least in part, reversible with a successful weight-loss program.

Abstract-In this study, the effect of different levels of thyroid hormone and metabolic activity on low density lipoprotein (LDL) oxidation was investigated. Thus, in 16 patients with hyperthyroidism, 16 with hypothyroidism, and 16 age-and sex-matched healthy normolipidemic control subjects, the native LDL content in lipid peroxides, vitamin E, ␤-carotene, and lycopene, as well as the susceptibility of these particles to undergo lipid peroxidation, was assessed. Hyperthyroidism was associated with significantly higher lipid peroxidation, as characterized by a higher native LDL content in lipid peroxides, a lower lag phase, and a higher oxidation rate than in the other two groups. This elevated lipid peroxidation was associated with a lower LDL antioxidant concentration. Interestingly, hypothyroid patients showed an intermediate behavior. In fact, in hypothyroidism, LDL oxidation was significantly lower than in hyperthyroidism but higher than in the control group. Hypothyroidism was also characterized by the highest ␤-carotene LDL content, whereas vitamin E was significantly lower than in control subjects. In hyperthyroidism but not in the other two groups, LDL oxidation was strongly influenced by free thyroxine blood content. In fact in this group, the native LDL lipid peroxide content and the lag phase were directly and indirectly, respectively, related to free thyroxine blood levels. On the contrary, in hypothyroidism LDL oxidation was strongly and significantly related to serum lipids. In conclusion, both hypothyroidism and hyperthyroidism are characterized by higher levels of LDL oxidation when compared with normolipidemic control subjects. In hyperthyroid patients, the increased lipid peroxidation was strictly related to free thyroxine levels, whereas in hypothyroidism it was strongly influenced by serum lipids. 1 Overt hyperthyroidism and hypothyroidism represent opposite clinical conditions characterized respectively by enhanced oxidative metabolism and reduced lipid and lipoprotein plasma levels and by reduced oxidative metabolism and markedly increased lipid and lipoprotein plasma levels. The hypermetabolic state that characterizes hyperthyroidism should accelerate free radical production in the mitochondria and induce changes in the antioxidant defense system. 2,3 In contrast, the metabolic suppression brought about by hypothyroidism is associated with a decrease in free radical production, and it has also been suggested that hypothyroidism protects tissues against acceleration of lipid peroxidation. [3][4][5] Increasing experimental and epidemiological evidence shows that high oxidative stress status favors oxidative modifications of LDL and plays an important role in the development of atherosclerosis.6-8 Nevertheless, hypothyroidism but not hyperthyroidism represents an important risk factor for atherosclerosis and coronary heart disease. 9 In view of well-documented strong relationships between blood cholesterol, LDL oxidation, and atherosclerosis, we used two opposite metabolic conditions, overt...

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!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!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!0.96 and females with WHR!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 !55 y and females aged !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.

Objective: To study signi®cant 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 pro®les 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 ®ve 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% con®dence 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 ®ndings 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 ®nancially supported by a grant

GUAGNANO, MARIA T., MARIA R. MANIGRASSO, ENZO BALLONE, ROSANNA DELLA VECCHIA, GRAZIANO RICCIONI, MARINA MARINOPICCOLI, MICHELE NUTINI, SERGIO SENSI, AND GIOVANNI DAVÌ. Association between serum leptin levels and 24-hour blood pressure in obese women. Obes Res. 2003; 11:549 -555. Objective: To assess the relationship between serum leptin and 24-hour blood pressure (BP) in obese women, according to body fat distribution. Research Methods and Procedures:A cross-sectional study was carried out in a population of 70 nondiabetic, normotensive, obese women (40 with android and 30 with gynoid type of obesity) and 20 nonobese healthy women as a control group. All subjects underwent 24-hour ambulatory BP monitoring. Blood samples were collected for serum leptin and plasma insulin measurements. Total cholesterol and high-density lipoprotein cholesterol were also measured. Results: Serum leptin levels were significantly higher in obese subjects than in controls, and they were more elevated in android obese women than in gynoid ones. Leptin levels were positively related to body mass index (BMI), insulin, and waist and hip circumferences in the android group. Among gynoid subjects, leptin levels showed positive associations with BMI and insulin. In women with android obesity, strong positive correlations (p Ͻ 0.001) were found between leptin levels and 24-hour systolic BP (SBP), daytime SBP, nighttime SBP, 24-hour diastolic BP (DBP), and daytime DBP. Multiple regression analyses, including age, insulin and leptin concentrations, BMI, and waist and hip circumferences on 24-hour and daytime SBP and DBP, showed that only leptin levels contributed to the variability of BP. Conclusions: Our study shows that serum leptin levels are directly related to 24-hour BP levels in normotensive women with android fat distribution, independently of BMI.