Impact of 3-year changes in fasting insulin and insulin resistance indices on incident hypertension: Tehran lipid and glucose study.

BACKGROUND: To examine the association between changes in fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), and insulin-glucose ratio (IGR) levels, over approximately 3 years with incident hypertension. METHODS: A total of 2814 Iranian participants (1123 men) without hypertension and known diabetes at baseline and the first examination were followed for a median of 6.32 years. The associations between quartiles of changes in fasting insulin and IR indices with incident hypertension were assessed using multivariate Cox proportional hazard regression analyses with first quartile as reference. The models were adjusted for baseline values of insulin or each IR index, and age, sex, smoking, physical activity, educational levels, marital status, history of cardiovascular diseases, baseline levels of systolic and diastolic blood pressures, estimated glomerular filtration rate, triglycerides, total cholesterol, high-density lipoprotein cholesterol, fasting plasma glucose (only for insulin change) and both body mass index (BMI) per se, and its change. Akaike's information criteria (AIC) was applied as indicator for goodness of fit of each predictive model. The discrimination ability of models was calculated using the Harrell's C statistic. RESULTS: During the study, 594 incident cases of hypertension (253 men) were identified. The 4th quartile of changes in insulin, HOMA-IR, and IGR showed hazard ratios (95% confidence interval) of 1.31 (1.01-1.69), 1.18 (0.92-1.52), and 1.53 (1.18-1.98) for hypertension, respectively, in fully-adjusted models. Changes in fasting insulin levels and IR indices showed significant increasing trends for incident hypertension, moving from 1st to 4th quartiles (all P-values < 0.05). Focusing on model fitness, no superiority was found between changes in fasting insulin, HOMA-IR, and IGR to predict incident hypertension. The discriminatory powers of changes in fasting insulin and IR indices as assessed by C index were similar (i.e. about 80%). CONCLUSION: Changes in fasting insulin and IR indices were significantly associated with developing hypertension among normotensive population even after considering BMI changes.

Insulinorresistencia e hipertensión gestacional: Estudio preliminar en una muestra del Municipio de La Plata / Insulin resistance and gestational hypertension: A preliminary study in a small population of La Plata Municipality / Hipertensão gestacional e resistência à insulina: Estudo preliminar numa amostra do Município de La Plata

Las mujeres embarazadas con insulino-sensibilidad disminuida están en riesgo de desarrollar trastornos hipertensivos. Utilizando el corte HOMA-IR en 2,64 la población en estudio fue dividida en dos grupos: (n=154 mujeres embarazadas), las que arrojaron un HOMA-IR basal (HOMA-0) <2,64 (no-insulinorresistentes; n=113) y aquellas con HOMA-0>2,64 (insulinorresistentes, n=41). Se analizaron: a) las concentraciones circulantes de glucosa e insulina durante una prueba de tolerancia oral a 75 g de glucosa (PTOG), y b) las relaciones entre varios parámetros de insulino-sensibilidad y la predicción del desarrollo de trastornos hipertensivos. A las mujeres embarazadas (semana 24-28) se les cuantificaron las concentraciones plasmáticas de glucosa e insulina a ambos tiempos de la PTOG. Se calcularon los valores de HOMA-IR y las relaciones glucosa a insulina (G:I) y se registraron parámetros antropométricos y resultados del embarazo. Las mujeres con HOMA-0 >2,64, aunque con glucemias en ayunas normales, mostraron mayores niveles de insulinemia y de HOMA-IR, y menores valores G:I en ambos tiempos de la PTOG. Estas mujeres embarazadas fueron las que tuvieron un mayor riesgo de desarrollar trastornos hipertensivos y mayores parámetros de morbilidad durante el período estudiado al compararlas con aquellas cuyo HOMA-0 fue <2,64.

Pregnant women with impaired insulin sensitivity are at risk for developing hypertensive disorders. By using a cut-off at 2.64 of the homeostasis model assessment (HOMA-IR) in basal condition (HOMA-0), the population under study (n=154 pregnant women) was split into two groups: 1) with basal HOMA- 0 <2.64 (non-insulin resistant; n=113) and 2) with basal HOMA-0 >2.64 (insulin resistant; n=41). Glucose and insulin circulating levels were analyzed throughout a 2-h oral 75 g glucose tolerance test (OGTT). The relationship between several parameters related to insulin resistance and the prevalence of pregnancy-induced hypertensive disorders was analyzed. Pregnant women (on week 24-28) were submitted to an OGTT, and glucose and insulin plasma concentrations were measured throughout the test. These peripheral metabolites levels and the values of the HOMA-IR and the glucose to insulin ratio (G:I) were analyzed. Anthropometric parameters and pregnancy outcome were recorded. Women with HOMA-0 >2.64 but normal fasting glycemia showed higher insulinemias, G:I values and HOMA-IR values at both times of the OGTT. The latter were at greater risk for developing late pregnancy-induced hypertension compared to women with HOMA-0 ≤2.64.

As mulheres grávidas com diminuição da sensibilidade à insulina correm o risco de desenvolver distúrbios hipertensivos. Usando o corte HOMA-IR 2,64, a população em estudo foi dividida em dois grupos: (n=154 mulheres grávidas), que deram um HOMA-IR basal (HOMA-0) ≤2,64 (não resistentes à insulina; n=113) e aquelas com HOMA-0 >2,64 (resistentes à insulina, n=41). Foram analisadas: a) as concentrações circulantes de glicose e insulina durante uma prova de tolerância oral a 75 g. de glicose (PTOG), e b) as relações entre diversos parâmetros de sensibilidade à insulina e a predição de desenvolver distúrbios de hipertensão. Foram quantificadas nas mulheres grávidas (24-28 semanas) as concentrações plasmáticas de glicose e insulina a ambos os tempos da PTOG. Valores de HOMA-IR foram calculados e as relações glicose a insulina (G:I) e se registraram parâmetros antropométricos e os resultados da gravidez. Mulheres com HOMA-0 >2,64, mas com glicemias em jejuns normais, mostraram níveis mais elevados de insulinemia e de HOMA-IR, e menores valores G:I em ambos os tempos da PTOG. Essas mulheres grávidas foram aquelas que tiveram maior risco de desenvolver distúrbios de hipertensão e maiores parâmetros de morbidade durante o período estudado em comparação com as mulheres cujo HOMA-0 foi ≤2,64.

Effect of fat type in baked bread on amylose-lipid complex formation and glycaemic response.

The formation of amylose-lipid complexes (ALC) had been associated with reduced starch digestibility. A few studies have directly characterised the extent of ALC formation with glycaemic response. The objectives of this study were to investigate the effect of using fats with varying degree of saturation and chain length on ALC formation as well as glycaemic and insulinaemic responses after consumption of bread. Healthy men consumed five test breads in a random order: control bread without any added fats (CTR) and breads baked with butter (BTR), coconut oil (COC), grapeseed oil (GRP) or olive oil (OLV). There was a significant difference in glycaemic response between the different test breads (P=0·002), primarily due to COC having a lower response than CTR (P=0·016), but no significant differences between fat types were observed. Insulinaemic response was not altered by the addition of fats/oils. Although BTR was more insulinotropic than GRP (P<0·05), postprandial ß-cell function did not differ significantly. The complexing index (CI), a measure of ALC formation, was significantly higher for COC and OLV compared with BTR and GRP (P<0·05). CI was significantly negatively correlated with incremental AUC (IAUC) of change in blood glucose concentrations over time (IAUCglucose) (r -0·365, P=0·001). Linear regression analysis showed that CI explained 13·3 % of the variance and was a significant predictor of IAUCglucose (ß=-1·265, P=0·001), but IAUCinsulin did not predict IAUCglucose. Our study indicated that a simple way to modulate glycaemic response in bread could lie in the choice of fats/oils, with coconut oil showing the greatest attenuation of glycaemic response.

Clinical Manifestation of 16 cases with Insulinoma or Nesidioblastosis / 대한내과학회지

Insulinoma is the most important cause of hyperinsulinemic hypoglycemia. Insulinoma can be cured by surgical management but diagnosis and localization are difficult due to their small size and variable clinical manifestation. We studied clinical manifestation of the patients who were diagnosed as insulinoma or nesidioblastosis. METHODS: We studied clinical charts of 16 patients who underwent operation under the impression of insulinoma from 1990 to 1997. RESULTS: 1) Of the 16 patients, 13 had insulinoma and 3 had nesidioblastosis. 2) Neuroglycopenic symptoms were present in all cases. Among them, loss of consciousness or confusion were present in 12 cases (75%). Adrenergic symptoms were present in 9 cases (56%). Mean symptom duration until diagnosis was 39 months(range; 15days~10years). 3) 72 hr fasting test showed hypoglycemia in all cases. 4) Insulin/glucose ratio was above 0.3 except for two cases. 5) CT and MRI had low sensitivity (38%) and specificity (33%) as a preoperative tumor localization tool, and more invasive technique, i.e., selective angiography and transhepatic portal vein sampling, were necessary in most cases. CONCLUSION: Nsidioblastosis may be more prevalent than previously suspected. Diagnosis of insulinoma is not always easy and invasive diagnostic methods should be considered when the clinical suspicion is high, even if biochemical and noninvasive localization tools give negative results.