Measured outcomes with hypnosis as an experimental tool in a cardiovascular physiology laboratory.

The authors detail their multidisciplinary collaboration of cardiologists, physiologists, neurologists, psychologists, engineers, and statisticians in researching the effects of hypnosis on the cardiovascular system and their additions to that incomplete literature. The article details their results and provides guidelines for researchers interested in replicating their research on hypnosis' effect on the cardiovascular system.

Oral disposition index in obese youth from normal to prediabetes to diabetes: relationship to clamp disposition index.

OBJECTIVE: We sought to assess the glucose disposition index using an oral glucose tolerance test (OGTT; oDI) compared with the glucose disposition index measured from the combination of the euglycemic-hyperinsulinemic and hyperglycemic clamps (cDI) in obese pediatric subjects spanning the range of glucose tolerance. STUDY DESIGN: Overweight/obese adolescents (n = 185) with varying glucose tolerance (87 normal, 54 impaired, 31 with type 2 diabetes, and 13 with type 1 diabetes) completed an OGTT and both a hyperinsulinemic-euglycemic and a hyperglycemic clamp study. Indices of insulin sensitivity and ß-cell function were calculated, and 4 different oDI estimates were calculated as the products of insulin and C-peptide-based sensitivity and secretion indices. RESULTS: Mirroring the differences across groups by cDI, the oDI estimates were greatest in normal glucose tolerance adolescents and lowest in type 2 diabetes mellitus and obese with type 1 diabetes mellitus adolescents. The insulin-based oDI estimates correlated with cDI overall (r ≥ 0.74, P < .001) and within each glucose tolerance group (r ≥ 0.40, P < .001). Also, oDI and cDI predicted 2-hour OGTT glucose similarly. CONCLUSIONS: The oDI is a simple surrogate estimate of ß-cell function relative to insulin sensitivity that can be applied to obese adolescents with varying glucose tolerance in large-scale epidemiological studies where the applicability of clamp studies is limited due to feasibility, cost, and labor intensiveness.

Dietary iron intake and cardiovascular outcome in Italian women: 10-year follow-up.

BACKGROUND: Both low and high iron levels have been associated with cardiovascular outcome. The aim of this study was to determine if dietary iron intake is a cardiovascular predictor in women at a population level. METHODS: A 138-item food frequency questionnaire (FFQ) was administered to 906 women aged 61.1±17.1 years from an unselected general population followed for 10 years. The mass of dietary items was calculated, and each food was resolved into its chemical components according to food composition tables conceived for Italian food. RESULTS: An inverse association between iron intake and cardiovascular morbidity was found. Incident nonfatal cerebrovascular events were 10 of 302 (3.3%), 4 of 302 (1.3%), and 2 of 302 (0.7%) in the first, second, and third tertiles of nonheme iron intake (p for trend <0.01), respectively; fatal cerebrovascular events were 20 of 302 (6.6%), 13 of 302 (4.3%), and 5 of 302 (1.7%), respectively (p<0.01); nonfatal coronary events were 24 of 302 (7.9%), 13 of 302 (4.3%), and 10 of 302 (3.3%), respectively, and fatal coronary events were 20 of 302 (6.6%), 15 of 302 (5.0%), and 10 of 302 (3.3%), respectively (p<0.01). Independenly of confounders, hazard ratios (HR) and 95% confidence intervals (CI) of being the first rather than third tertile of nonheme iron intake were 5.00 (1.08-23.26), 3.18 (1.41-10.12), and 3.25 (1.39-7.59), respectively, for cerebrovascular and 2.48 (1.17-5.25), 2.25 (1.03-4.80), and 2.51 (1.39-4.53), respectively, for coronary events. Heme iron intake was not a predictor. CONCLUSIONS: Based on a longitudinal population analysis, low iron intake seems to be an independent predictor of cerebrovascular and coronary morbidity and mortality in women.

Surrogate estimates of insulin sensitivity in obese youth along the spectrum of glucose tolerance from normal to prediabetes to diabetes.

CONTEXT: In epidemiological studies of childhood obesity, simple and reliable surrogate estimates of insulin sensitivity are needed because the gold standard, the hyperinsulinemic-euglycemic clamp, is not feasible on a large scale. OBJECTIVE: To examine the correlation of fasting and oral glucose tolerance test (OGTT)-derived surrogate indices of insulin sensitivity with the hyperinsulinemic-euglycemic clamp in obese adolescents with normal glucose tolerance, prediabetes, and diabetes. PATIENTS AND DESIGN: A total of 188 overweight/obese adolescents (10 to <20 yr old) who completed a standard 2-h OGTT and 3-h hyperinsulinemic-euglycemic clamp were included. Fasting-derived surrogates [fasting glucose (G(F)), fasting insulin (I(F)), 1/I(F), G(F)/I(F), homeostasis model assessment and quantitative insulin sensitivity check index] and OGTT-derived surrogates [whole-body insulin sensitivity index and the ratio of glucose and insulin areas under the curve (Gluc(AUC)/Ins(AUC))] were calculated. MAIN OUTCOME MEASURES: We evaluated the correlations between the clamp-measured insulin sensitivity and the surrogate estimates and area under the receiver operating characteristic curves. RESULTS: Fasting indices (1/I(F), G(F)/I(F), homeostasis model assessment of insulin sensitivity, and quantitative insulin sensitivity check index) correlated significantly with clamp insulin sensitivity (r = 0.82, 0.78, 0.81, and 0.80, respectively), with lower correlations between the OGTT surrogates and clamp (whole-body insulin sensitivity index, r = 0.77; Gluc(AUC)/Ins(AUC), r = 0.62). The area under the receiver operating characteristic curves was more than or equal to 0.94 for all surrogates except Gluc(AUC)/Ins(AUC.) Across quartiles of clamp-measured insulin sensitivity, there was a significant overlap in individual values of I(F), 1/I(F), and G(F)/I(F). CONCLUSION: In obese adolescents with normal or impaired glucose tolerance or diabetes, OGTT-derived surrogates do not offer any advantage over the simpler fasting indices, which correlate strongly with clamp insulin sensitivity. Surrogate indices of insulin sensitivity could be used in epidemiological studies but not to define insulin resistance in individual patients or research subjects.