Subclinical Diabetes

ABSTRACT Type 2 diabetes mellitus (T2DM) is increasing in prevalence worldwide, and those non-diagnosed or misdiagnosed comprise a significant group compared to those diagnosed. Accumulated scientific evidence indicate that the current diagnostic markers (fasting glycemia, 2h glycemia after an oral glucose load and HbA1c) are indeed late diagnostic criteria when considering the incidence of diabetes-related complications and comorbidities, which are also at high risk in some groups among normoglycemic individuals. Additionally, the earlier identification of future risk of diabetes is desirable since it would allow better adherence to preventive actions such as lifestyle intervention, ultimately avoiding complications and minimizing the economic impact/burden on health care expenses. Insulin resistance and hyperhormonemia (insulin, amylin, glucagon) are non-disputable hallmarks of T2DM, which already takes place among these normoglycemic, otherwise health subjects, characterizing a state of subclinical diabetes. Insulin resistance and hyperinsulinemia can be computed from fasting plasma insulin as an independent variable in normoglycemia. An overview of the current diagnostic criteria, disease onset, complications, comorbidities and perspectives on lifestyle interventions are presented. A proposal for early detection of subclinical diabetes from routine evaluation of fasting plasma insulin, which is affordable and robust and thus applicable for the general population, is further suggested.

Neuroprotective effects of Vitis vinifera extract on prediabetic mice induced by a high-fat diet

BACKGROUND/AIMS: Vitis vinifera grape seed extract (VVE) contains oligomeric proanthocyanidins that show antioxidant and free radical-scavenging activities. We evaluated VVE for its neuroprotective effect in prediabetic mice induce by a high-fat diet (HD). METHODS: Mice were divided into four groups according to VVE dose: those fed a normal diet (ND; n = 10), HD (n = 10), HD with 100 mg/kg VVE (n = 10), and HD with 250 mg/kg VVE (n = 10). After 12 weeks, immunohistochemical analyses were carried out using a polyclonal antibody against antiprotein gene product 9.5 (protein-gene-product, 9.5), and intraepidermal innervation was subsequently quantified as nerve fiber abundance per unit length of epidermis (intraepidermal nerve fiber, IENF/mm). RESULTS: Daily administration of VVE at doses of 100 or 250 mg/kg for 12 weeks protected HD mice from nerve fiber loss compared to untreated mice, as follows (IENF/mm): controls (40.95 +/- 5.40), HD (28.70 +/- 6.37), HD with 100 mg/kg (41.14 +/- 1.12), and HD with 250 mg/kg (48.98 +/- 7.01; p < 0.05, HD with VVE vs. HD). CONCLUSIONS: This study provides scientific support for the therapeutic potential of VVE in peripheral neuropathy in an HD mouse model. Our results suggest that VVE could play a role in the management of peripheral neuropathy, similar to other antioxidants known to be beneficial for diabetic peripheral neuropathy.

Hemoglobina glicosilada A1c vs. glucemia plasmática en ayunas de pacientes ambulatorios de un laboratorio médico / Glycosylated haemoglobin A1c compared to fasting plasma glucose in outpatients referred to a medical laboratory

Objetivo Comparar la prueba hemoglobina glicosilada (HbA1c) en diferentes puntos de corte, con la prueba de glucemia plasmática en ayunas (GPA); para medición de glucosa en sangre en pacientes ambulatorios de un laboratorio médico de la ciudad de Medellín, entre marzo y abril de 2010. Métodos Estudio en 1016 muestras de sangre de pacientes referidos a un laboratorio médico. Se obtuvo la concordancia entre las pruebas (Índice de Kappa), se calcularon sensibilidad y especificidad, además se evaluaron diferentes puntos de corte para la prueba HbA1c con la curva ROC. Se usó correlación de Spearman para establecer la asociación entre GPA y HbA1c. Resultados El valor promedio de HbA1c fue 5,7 % ±0,8 y de la GPA fue 96 mg/dL±26,1; y esta última fue mayor en hombres (99,04±32,7). El 75,4 % de las muestras fueron normales para diagnóstico de diabetes con la prueba GPA, y con la HbA1c el 51,4 % clasificaron en este rango. El punto de corte donde la combinación sensibilidad-especificidad presenta los mejores valores para HbA1c fue 6,2 %. Discusión La prueba HbA1c presentó valores altos de sensibilidad y especificidad, por lo que su uso rutinario en el diagnóstico de diabetes mellitus podría contribuir a la búsqueda activa y la detección precoz de casos, que aseguren un mejor control de los factores de riesgo.

Objective Comparing haemoglobin A glycosylate (HbA1c) at different cutoff points for blood glucose measurement to the fasting plasma glucose (FPG) test in outpatients visiting a medical laboratory in the city of Medellin between March and April 2010. Methods 1,016 blood samples were studied from patients who had been referred to a medical laboratory. Agreement was obtained between tests (Kappa index); sensitivity and specificity were calculated. Different cutoff points for the HbA1c test were also evaluated with the ROC curve. Spearman correlation was used to establish association between FPG and Hb A1c. Results Average HbA1c was 5.7 %±0.8 and average FPG was 96 mg/dL±26.1; this was higher in men (99.04±32.7). 75.4 % of the samples came within the normal range for diagnosing diabetes with the FPG test, compared to 51.4 % with the HbA1c test. The cutoff point where combined sensitivity and specificity presented the best HbA1c value in this study group was 6.2 %. Discussion The HbA1c test had high sensitivity and specificity values, so its routine use in diagnosing diabetes mellitus could contribute towards active and early detection of cases to ensure better control of risk factors.

High cardiorespiratory fitness is more beneficial in pre-diabetic men than women

OBJECTIVES: To investigate gender-specific relationships between cardiorespiratory fitness and factors that predict the development of diabetes and to identify the risk factors that predict fasting plasma glucose and 2-hour plasma glucose levels. INTRODUCTION: Different risk factors (e.g., low cardiorespiratory fitness) may cause elevated plasma glucose levels in men compared to women. Therefore, gender-specific analyses are needed. METHODS: Cardiorespiratory fitness (maximal power output achieved during a standard cycle ergometry test), resting blood pressure, total serum cholesterol, high-density lipoprotein cholesterol and triglyceride levels were measured in 32 pre-diabetic men (mean age: 57.2 + 6.8 years; mean body mass index (BMI): 28.5 + 3.0 kg/m²) and 40 pre-diabetic women (mean age: 55.0 + 7.3 years, mean BMI: 30.4+5.7 kg/m²). A stepwise regression with backward variable selection was performed to construct models that predict 2-hour and fasting plasma glucose levels. RESULTS: Maximal power output was inversely related to the 2-hour plasma glucose level in the entire group (r= -0.237, p<0.05), but this relationship was significant only for males (r= -0.404, p<0.05). No significant correlation was found between female gender and cardiorespiratory fitness. Age and cardiorespiratory fitness were significant predictors of 2-hour plasma glucose levels in men. High-density lipoprotein cholesterol was predictive of 2-hour plasma glucose levels in women. Triglycerides in women and BMI in men were the only predictors of fasting plasma glucose levels. CONCLUSIONS: These findings may have consequences for the development of gender-specific diabetes prevention programs. Whereas increasing cardiorespiratory fitness should be a key goal for men, improving the lipid profile seems to be more beneficial for women. However, the present results do not negate the positive effects of increasing cardiorespiratory fitness in women.

A study to find out the proportion of prediabetes in patients with acute coronary syndrome in a medical college of Kolkata.

Prediabetes is now considered as a definite entity for increased incidence of cardiovascular disease and a potent risk for progression to type 2 diabetes mellitus. As macrovascular disease is the commonest cause of increased mortality in dysglycaemic individuals (prediabetes and diabetes) by 2-4 times as opposed to normal individuals, clinicians do encounter patients with cardiovascular disease of varying severity regularly. There are increased constellation of other cardiovascular risk factors (hypertension, dyslipidaemia, etc), in prediabetes as compared to normal population. Here a study was carried out among 62 acute coronary syndrome patients who were admitted in a tertiary care hospital in Kolkata to find out the proportion of prediabetes in them. Majority of the patients (54.8%) were in the age group of 45-64 years and were males (77.4%). The study showed 48.4% of all acute coronary syndrome patients were prediabetic and 25% were diabetic. The proportion of impaired fasting glucose and impaired glucose tolerance were 19.4% and 22.6% respectively. So, altogether 72.4% patients were dysglycaemic. Out of all acute coronary syndrome patients, non-ST elevated myocardial infarction group had 50% prediabetic patients, ST elevated myocardial infarction group had 50% prediabetic patients and unstable angina group have 45.8% prediabetic patients. So, all patients of acute coronary syndrome should be screened to detect hyperglycaemia in early stage to prevent further development of diabetes mellitus and also further cardiovascular events.

Prediabetes and hypertension.

Prediabetes occurs due to two basic defects--insulin resistance and/or beta-cell failure. An observation suggested that insulin resistance may be associated with essential hypertension. There are some thoughts to favour the argument that insulin resistant Individuals are at a higher risk to develop hypertension as compared to insulin sensitive individuals. Some pathophysiological causes which have been commonly observed and hypothesised are narrated in this article. Management of hypertension in prediabetes should include antihypertensives and therapeutic lifestyle modification. To manage hypertension in prediabetes one should think for dietary modification, reduced salt intake, physical activity, smoking cessation, use of statins and antihypertensives.

Pancreatic beta cell function in normoglycaemic offspring of diabetic parents.

The aim of the study was to look for any time-realted fluctuation in the pancreatic beta cell function in normal offspring of diabetic parents, over a period of three years. Serum insulin (IRI) and C-peptide (CP) responses to oral glucose were reevaluated three years after the initial study in 25 normoglycaemic offspring of conjugal Type 2 diabetic parents. The mean area under the curve of IRI (AUC IRI) response was higher than normal control value in the offspring at both time points (P < 0.01) and the two values did not differ much. The 2 hr IRI was also significantly higher (P < 0.05) than the control value. CP responses at both time points in the offspring did not differ from the mean control value. Wide fluctuations in the individual IRI were noted on follow-up despite similar plasma glucose response. Follow-up IRI was higher in 6, lower in 5 (+/- 25% of the initial) and remained unaltered in the other 4 offspring. The corresponding CP showed increased values in 3, decreased values in 5 and no change in 7 offspring. The fluctuations were nonuniform in nature among the individuals studied. Disparity between the IRI and CP responses were present in 5 offspring during the follow-up. This study thus shows that wide fluctuations in insulin responses occur even in the normoglycaemic offspring of diabetic parents.