Analysis of color Doppler signal intensity variation after levovist injection: a new approach to the diagnosis of thyroid nodules.

The objective of this study was to evaluate the usefulness of a galactose-based ultrasonographic contrast agent, Levovist (Schering AG, Berlin, Germany), in differentiating benign from malignant thyroid nodules by analysis of the time-intensity curves correlating the variation of the intensity signal value during the contrast transit time. Fifty-four patients scheduled for surgical removal of a nodule or the thyroid gland or both after cytologic examination were enrolled in this study; all of the nodules underwent a baseline color and power Doppler evaluation and then to a color Doppler examination after an intravenous bolus injection of Levovist. The time-intensity curves were analyzed with respect to the histologic results. Carcinomas showed a significantly earlier arrival time of Levovist than nodular hyperplastic benign nodules and adenomas (8.1 +/- 1.41 versus 19.6 +/- 2.2 and 16.1 +/- 2.8 seconds; P < .0001), although no significant difference occurred between hyperplastic benign nodules and adenomas; carcinomas and adenomas showed an earlier time to peak than hyperplastic benign nodules (14.6 +/- 1.2 and 23.1 +/- 3.8 versus 33.0 +/- 3.0 seconds; P < .0001). No significant difference was found in baseline, peak, final intensity signal, and percent variation of intensity signal among hyperplastic benign nodules, adenomas, and carcinomas. Although cytologic examination still remains the standard of reference for the presurgical diagnosis of thyroid nodules, the preliminary data of this pilot study demonstrate that the analysis of time-intensity curves after Levovist injection might provide useful, complementary, and quantitative information to differentiate benign from malignant thyroid nodules.

Risk of diabetes in the new diagnostic category of impaired fasting glucose: a prospective analysis.

OBJECTIVE: To prospectively evaluate progression to diabetes in individuals with impaired glucose regulation as defined according to fasting glucose alone or an oral glucose tolerance test (OGTT) (i.e., both fasting and postload glucose) to compare the ability of these two screening methods to identify people at high risk of developing diabetes. RESEARCH DESIGN AND METHODS: A working population of 1,245 nondiabetic telephone company employees aged 40-59 years was studied by OGTT in 1980. Participants were classified according to baseline fasting glucose only (as encouraged by the American Diabetes Association [ADA]) or OGTT (as recommended by the 1998 World Health Organization [WHO] consultation). Progression to diabetes was evaluated 11.5 years later according to the 1997 ADA criteria of a fasting plasma glucose level > or =7.0 mmol/l. RESULTS: With the use of the OGTT, baseline prevalence of impaired glucose regulation was substantially higher than that with fasting glucose alone (7.2 vs. 3.2%); the two groups only overlap for 40.9% of the cases because a fairly large number of people with postload hyperglycemia (59.1%) have normal fasting glucose. Progression to diabetes in participants with normal fasting glucose and postload hyperglycemia is significantly more frequent than that of people with normoglycemia (32.5 vs. 7.2%; P < 0.001) and not significantly different from that of people with both fasting and postload hyperglycemia (i.e., 44.0%). However, the former are not identified as being at unusually high risk of diabetes unless an OGTT is performed. When the use of fasting glucose alone or OGTT was validated as a marker of progression to diabetes, sensitivity was substantially higher for the OGTT (33.3 vs. 9.0%) without major differences in specificity (92.6 vs. 97.0%). CONCLUSIONS: These data (the only data so far available in Caucasians) support the viewpoint that for the identification of people at high risk of diabetes, the use of the OGTT should be maintained.

Does impaired glucose tolerance predict hypertension? A prospective analysis.

This study evaluates prospectively the relationship between impaired glucose tolerance (IGT) and blood pressure. From a population of 1376 men and women aged 40-59 years, all those with IGT (n = 54) plus 133 age- weight- and sex-matched normoglycaemic control subjects were selected after excluding treated hypertensive patients. Blood pressure, fasting and postload blood glucose and plasma insulin were measured. At 11.5 years after the first visit 76% of the IGT patients and 80% of the control subjects were re-examined. At baseline blood pressure was significantly higher in IGT patients than in control subjects (systolic 135.5 +/- 2.3 vs 127.9 +/- 1.4 mmHg, p < 0.001; and diastolic 88.0 +/- 1.5 vs 84.7 +/- 0.7 mm Hg, p < 0.05) independent of age, gender, weight, antihypertensive medication and insulinaemia. Accordingly, hypertension was more frequent in subjects with IGT (odds ratio 2.1, 95% confidence, interval (CI) 0.9-4.9). Postload insulin was significantly associated with hypertension--both at univariate and multivariate analysis--in normoglycaemic subjects, but not in those with IGT. At follow-up systolic blood pressure increased in both groups; the increase was smaller in patients with IGT (6.0 +/- 2.4 vs 12.3 +/- 1.6 mm Hg p < 0.05). Likewise, the 11.5 years' cumulative incidence of hypertension was not significantly different in subjects with baseline IGT or normoglycaemia; if anything it was lower in the IGT group (odds ratio 0.36, 95% CI 0.1-1.2). In multivariate analysis incidence of hypertension was associated positively with baseline blood pressure (p < 0.0003) and negatively with IGT status p < 0.03), while no significant association was found with insulin. In conclusion, the findings of this study question IGT as a risk factor for hypertension. Furthermore, these data do not indicate a major role for hyperglycaemia and hyperinsulinaemia per se in the aetiology of hypertension and suggest that IGT and hypertension share one or more pathogenetic factor(s) (i.e., insulin resistance, hyperactivity of the sympathetic nervous system, etc.), which induce deterioration of blood pressure control first, and hyperglycaemia later.

Early abnormalities of cardiac function in non-insulin-dependent diabetes mellitus and impaired glucose tolerance.

The aim of this study was to evaluate the role of diabetes and minor abnormalities of glucose homeostasis, such as impaired glucose tolerance, as determinants of cardiac function and structure in a working population. We studied a population-based sample of 64 telephone company employees (both sexes, mean age 58 years): 25 with normoglycemia, 15 with impaired glucose tolerance, and 24 with non-insulin-dependent diabetes mellitus (NIDDM) diagnosed by oral glucose tolerance test according to the recommendations of the World Health Organization. Subjects with myocardial ischemia were excluded. Left ventricular end-systolic dimension, indexed to body surface area, was greater in those with NIDDM (p < 0.05) and in those with impaired glucose tolerance (p < 0.05) with respect to normoglycemic persons. The ratio of the peak early diastolic velocity wave to the late diastolic wave was lower in those with NIDDM (p < 0.05) and in those with impaired glucose tolerance (p < 0.05) than in participants with normoglycemia. Body mass index and blood pressure were similar in the 3 groups. These results clearly indicate that early abnormalities of cardiac structure and function are observed not only in patients with NIDDM, but also in those with impaired glucose tolerance, independent of the confounding role of myocardial ischemia, body weight, and blood pressure.

Regression of left ventricular hypertrophy and systolic function in hypertensive patients during long-term treatment with ketanserin.

It is now generally accepted that antihypertensive therapy can induce regression of left ventricular hypertrophy (LVH) in hypertensive subjects. However, the influence of LVH reversal on both the systolic and diastolic functions, and particularly the ability of the heart to meet sudden overloads caused by exercise and/or recurrence of hypertension, remain unanswered questions. The long-term effects of ketanserin, a selective serotonin S2-receptor antagonist with additional alpha 1-adrenergic blocking properties, on LVH and systolic function were studied in 13 untreated subjects (age range 35-55 years) with mild-to-moderate essential hypertension, echocardiographic evidence of LVH, and normal ejection fraction. Blood pressure values and echocardiographic measurements of dimensions, wall thicknesses, and indices of LV mass were determined before and after 3, 6, and 12 months treatment; ejection fractions at rest and during exercise were evaluated by equilibrium multigated radionuclide angiocardiography at baseline and after 12 months of therapy. Mean arterial pressure was significantly reduced from the first month of treatment (p less than 0.001) and remained well controlled up to the end of the trial. Both posterior and septum wall thicknesses decreased after 3 months of therapy and remained stable throughout the whole study period. LV mass index decreased from a mean +/- SD of 187.7 +/- 47.6 g/m2 to a mean of 157.81 +/- 31.63 g/m2 (p less than 0.01) at the third month, reaching greater decreases after 6 months (156.05 +/- 31.00 g/m2) and after 12 months (153.21 +/- 28.80 g/m2) of treatment. A significant correlation was found between LV mass and posterior wall thickness at the different observation times in the study. Finally, the regression of LVH at the end of therapy was not associated with impairment of systolic function, as assessed by measurements of ejection fraction at rest and during exercise.