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Flavia Tosi

Publications and source records attributed to Flavia Tosi.

4 recordsLinked to original sources
PubMed2006

Clustering of cardiovascular risk factors associated with the insulin resistance syndrome: assessment by principal component analysis in young hyperandrogenic women.

OBJECTIVE: Hyperinsulinemia is often associated with several metabolic abnormalities and increased blood pressure, which are risk factors for cardiovascular disease. It has been hypothesized that insulin resistance may underlie all these features. However, recent data suggest that some links between insulin resistance and these alterations may be indirect. The aim of our study was to further investigate this issue in a sample of young hyperandrogenic women, who often show insulin resistance and other metabolic abnormalities typical of the insulin resistance syndrome. RESEARCH DESIGN AND METHODS: We tested the hypothesis of a single factor underlying these features by principal component analysis, which should recognize one component if a single mechanism explains this association. The analysis was carried out in a sample of 255 young nondiabetic hyperandrogenic women. Variables selected for this analysis included the basic features of the insulin resistance syndrome and some endocrine parameters related to hyperandrogenism. RESULTS: Principal component analysis identified four separate factors, explaining 64.5% of the total variance in the data: the first included fasting and postchallenge insulin levels, BMI, triglycerides, HDL cholesterol, and uric acid; the second, BMI, blood pressure, and serum free testosterone; the third, fasting plasma glucose, postchallenge glucose and insulin levels, serum triglycerides, and free testosterone; and the fourth, postchallenge plasma insulin, serum free testosterone, and gonadotropin-releasing hormone agonist-stimulated 17-hydroxyprogesterone. CONCLUSIONS: These results support the hypothesis of multiple determinants in the clustering of abnormalities in the so-called insulin resistance syndrome.

Adult↗
PubMed2003

Combination treatment with metformin and glibenclamide versus single-drug therapies in type 2 diabetes mellitus: a randomized, double-blind, comparative study.

To compare efficacy and tolerability of combination treatment with metformin and sulfonylurea with each of these drugs alone in the treatment of type 2 diabetes, 88 type 2 diabetic subjects (hemoglobin A1c [HbA1c] levels, 8.0%+/-1.0%; age, 57.3+/-7.1 years; body mass index [BMI]. 27.0+/-2.6 kg/m2; diabetes duration, 9.8+/-8.2 years; means +/- SD) were randomly assigned to double-blind treatment with metformin (500 to 3,000 mg/d), glibenclamide (5 to 15 mg/d), or their combination (metformin 400 to 2,400 mg/d + glibenclamide 2.5 to 15 mg/d) for 6 months. Thereafter, groups were crossed over for the following 6 months. Thus, each patient received metformin or glibenclamide alone, and the combination treatment. Doses were titrated to obtain HbA1c levels < or = 6.0% and fasting plasma glucose levels less than 140 mg/dL. Eighty patients concluded both treatment periods and were included in the analysis of treatment efficacy. In patients receiving metformin or glibenclamide alone, the maximal dose was reached in 21 and 25 patients, respectively; 8 and 15 of these subjects, respectively, required the maximal dose when they were on the combination treatment. During the study, 4 (10.0%) subjects receiving metformin, 7 (17.1%) receiving glibenclamide, and 31 (39.2%) receiving the combination treatment reached HbA1c levels < or = 6.0%. Moreover, when efficacy of the combination treatment on glycemic control was compared with that of single-drug therapies in each individual patient, the combination was significantly more effective than either metformin or glibenclamide (HbA1c after treatment, 6.1%+/-1.1% v 7.3%+/-1.4%, and 6.5%+/-0.7% v 7.6%+/-1.5%, respectively, both P<.0001). In conclusion, combination treatment with metformin and sulfonylurea is more effective than these drugs alone in improving glycemic control in type 2 diabetes, while also allowing a reduction of the dosage of each drug.

Blood Glucose↗
PubMed2003

Selective venous sampling in diagnosing ACTH-dependent hypercortisolism.

PURPOSE: To evaluate the sensitivity of selective sampling from the inferior petrosal sinuses in the differential diagnosis of ACTH-dependent hypercortisolism with non-diagnostic pituitary imaging. MATERIALS AND METHODS: Between 1987 and 2001, 17 patients (14 women and 3 men, aged 18-63 years) with ACTH-dependent hypercortisolism and negative X-ray of the sellar region, underwent simultaneous bilateral sampling from the inferior petrosal sinuses with ACTH measurement, at baseline and after stimulation with CRH (100 micro i.v.). Baseline samplings were also carried out at the level of the infrarenal and suprarenal inferior vena cava, of the adrenal and suprahepatic veins, of the superior vena cava, of the jugular veins, and of a peripheral vein. A central/peripheral gradient >2 at baseline and/or one >3 after stimulation with CRH was considered indicative of the pituitary origin of ACTH. Bilateral femoral venous catheterization was performed in an angiographic room using 5-French introducers after local anaesthesia. Selective catheterization of the inferior petrosal sinuses was achieved with 100 cm-long, steam-bent (45 degrees) 5-French catheters, without lateral holes. RESULTS: Twelve patients exhibited ACTH central/ peripheral gradients indicating the pituitary origin of the hormonal hyperincretion; this was confirmed by surgical exploration of the hypophysis in 10 patients, whereas 2 refused surgery and were therefore "lost". Of the five patients without ACTH central/peripheral gradients, one had an adrenal metastasis from ACTH-secreting lung neoplasia (with ACTH gradient in the blood flowing back from the adrenal gland), one had a hepatic CRHoma (with high levels of CRH in the suprahepatic veins), whereas the origin of the hyperincretion remained indeterminate in three. CONCLUSIONS: Bilateral simultaneous selective sampling from the inferior petrosal sinuses for ACTH measurements proved to be highly sensitive and free of complications in the differential diagnosis of ACTH-dependent forms of hypercortisolism.

Adolescent↗