Evidence based medicine has changed the manner in which medicine is practiced and learned. Epidemiological studies, meta-analyses and systematic reviews have been used to create algorithms for the treatment of hyperglycemia in patients with type 2 diabetes. Recently, several randomized controlled trials (i.e. ACCORD, ADVANCE, VADT) have generated new and valuable information regarding the benefits and risks of achieving optimal glucose control. As a result, guidelines and algorithms have been updated. However, many aspects remain controversial. In this article, the clinical implications of the existing guidelines are critically analyzed. The limitations of the current guidelines include the lack of applicability to relevant diabetic subgroups, the exclusion of important factors that modify the therapeutic response to glucose-lowering agents and the limited recognition of the importance of the socioeconomic situation on treatment efficacy. Many subgroups of patients have not been included in the studies used to generate recommendations. There is insufficient evidence to support the use of current treatment recommendations in patients with early onset type 2 diabetes, patients with advanced microvascular complications, and the elderly with or without chronic complications. The characteristics of the candidates for conservative or intensive treatment are poorly defined. Interventions are recommended without considering clinical variables (i.e. obesity, time since diagnosis or prolonged exposure to hyperglycemia) that may modify treatment efficacy and the occurrence of side effects. Finally, no consideration is given to the socioeconomic context of the population in which the guidelines are to be applied.

OBJECTIVE To describe the prevalence of lipid abnormalities found in the Mexican National Health and Nutrition Survey 2006 (ENSANut 2006). MATERIAL AND METHODS Information was obtained from 4 040 subjects aged 20 to 69 years, studied after a 9- to 12-hour fast. RESULTS Median lipid concentrations were: cholesterol 198.5 mg/dl, triglycerides 139.6 mg/dl, HDL-cholesterol 39.0 mg/dl, non-HDL-cholesterol 159.5 mg/dl and LDL-cholesterol 131.5 mg/dl. The most frequent abnormality was HDL-cholesterol below 40 mg/dl with a prevalence of 60.5% (95%CI 58.2-62.8%). Hypercholesterolemia (> 200 mg/dl) had a frequency of abnormality of 43.6% (95%CI 41.4-46.0%). Only 8.6% of the hypercholesterolemic subjects knew their diagnosis. Hypertriglyceridemia (>or= 150 mg/dl) was observed in 31.5% (IC 95% 29.3-33.9%) of the population. CONCLUSIONS The ENSANUT 2006 data confirm that the prevalence of hypoalphalipoproteinemia and other forms of dyslipidemia in Mexican adults is very high.

OBJECTIVE: To describe the prevalence of lipid abnormalities found in the Mexican National Health and Nutrition Survey 2006 (ENSANut 2006). MATERIAL AND METHODS: Information was obtained from 4 040 subjects aged 20 to 69 years, studied after a 9- to 12-hour fast. RESULTS: Median lipid concentrations were: cholesterol 198.5 mg/dl, triglycerides 139.6 mg/dl, HDL-cholesterol 39.0 mg/dl, non-HDL-cholesterol 159.5 mg/dl and LDL-cholesterol 131.5 mg/dl. The most frequent abnormality was HDL-cholesterol below 40 mg/dl with a prevalence of 60.5% (95%CI 58.2-62.8%). Hypercholesterolemia (> 200 mg/dl) had a frequency of abnormality of 43.6% (95%CI 41.4-46.0%). Only 8.6% of the hypercholesterolemic subjects knew their diagnosis. Hypertriglyceridemia (> 150 mg/dl) was observed in 31.5% (IC 95% 29.3-33.9%) of the population. CONLUSIONS: The ENSANUT 2006 data confirm that the prevalence of hypoalphalipoproteinemia and other forms of dyslipidemia in Mexican adults is very high.OBJETIVO: Presentar la prevalencia de las dislipidemias observada en la Encuesta Nacional de Salud y Nutrición 2006 (ENSANUT 2006). MATERIAL Y MÉTODOS: Se incluyeron 4040 individuos con edad entre 20 y 69 años estudiados bajo un ayuno de 9 a 12 horas. RESULTADOS: Las concentraciones medias de los lípidos sanguíneos fueron colesterol 198.5 mg/dl, triglicéridos 139.6 mg/dl, colesterol HDL 39.0 mg/dl, colesterol noHDL 159.5 mg/dl y colesterol LDL 131.5 mg/dl. La anormalidad más común fue la hipoalfalipoproteinemia (colesterol HDL< 40 mg/dl); su prevalencia fue 60.5% (IC95% 58.2-62.8%). La hipercolesterolemia (colesterol > 200 mg/dl) fue la segunda anormalidad en frecuencia, con 43.6% (IC95% 41.4-46.0%). Sólo el 8.6% de los casos conocía su diagnóstico. La hipertrigliceridemia (> 150 mg/dl) fue observada en 31.5% (IC95% 29.3-33.9%) de la población en estudio. CONCLUSIONES: Los datos de la ENSANUT 2006 confirman que la prevalencia de hipoalfalipoproteinemia y otras formas de dislipidemia es muy alta en los adultos mexicanos.

An Expert Committee of the American Diabetes Association and the European Association for the Study of Diabetes recommended a move to the use of HbA1c level to diagnose diabetes mellitus. Diagnosis should be made if the A1c level is > or = 6.5%. HbA1c provides a reliable measure of chronic glycemia, correlates well with the risk of long-term diabetes complications and technical limitations for standardization have been overcome in laboratories of the U.S. and Europe. The objective of this paper is to analyze critically the advantages and disadvantages of the use of HbA1c as a diagnostic method of diabetes in a developing country. The lack of a universal threshold for the diagnosis of diabetes, the cost of the test and the absence of the standardization network in the majority of the countries are major arguments for not including HbA1c as diagnostic criteria of diabetes. HbA1c diagnostic criteria has a low sensitivity. As a result, there is a lack of agreement between the HbA1c criteria with the other diagnostic methods that lead into significant variations in the number of affected cases. In addition, sensitivity and specificity vary among ethnic groups. No study has compared the diagnostic properties of the HbA1c in Latin America. In conclusion, the logistic limitations that exist in a large proportion of developing countries and the unsolved uncertainties that exist for the definition of the A1c criterion are strong arguments against the inclusion of HbA1c among the diagnostic criteria of diabetes.

OBJECTIVE:To estimate the percentage of Mexican adults that may require lipid-lowering treatment according to National Cholesterol Education Program-III guidelines, using data from the National Health and Nutrition Survey 2006 (ENSANut 2006).MATERIAL AND METHODS:Information was obtained from 4 040 subjects aged 20 to 69 years, studied after a 9 to 12 hours fast.RESULTS:A cardiovascular risk equivalent was found in 13.8% and >or=2 risk factors were present in 31.5% of the population. LDL-C concentrations were above the treatment goal in 70% of the high-risk group and in 38.6% of subjects with >or=2 risk factors. Nearly 12 million Mexicans should be taught how to change their lifestyles and close to 8 million individuals require drug therapy to decrease their cardiovascular risk.CONCLUSIONS:Thirty percent of Mexican adults require some form of lipid-lowering treatment (lifestyle modifications in 36.25%, drug therapy in 24.19%).

OBJECTIVE:To report a case of a proinsulin-secreting islet cell adenoma in which the diagnosis was obscured by an ultraspecific insulin assay. METHODS:We describe the case of a 46-year-old woman, who presented with fasting hypoglycemia and appropriately low insulin values. RESULTS:A prolonged supervised fast produced symptomatic hypoglycemia (20 mg/dL) after only 7 hours. During the entire fasting test, highly specific insulin remained at <3 mIU/L, with a median value (and interquartile range) of 0.9 (0.8 to 2.3) mIU/L, when the glucose concentration was <50 mg/dL. The serum C-peptide level remained high normal (mean +/- SD, 2.7 +/- 0.6 ng/mL; normal fasting levels, 0.8 to 3.9), and no evidence of sulfonylurea use was detected in the patient's urine. Circulating proinsulin levels were persistently high (>200 pmol/L in all determinations when hypoglycemia was present; expected value, <5 pmol/L). Magnetic resonance imaging and endoscopic ultrasonography confirmed the presence of a 2.5-cm tumor in the head of the pancreas. A proinsulin-secreting islet cell tumor was diagnosed. Surgical resection of the tumor was successfully accomplished, but diabetes mellitus developed 4 months postoperatively. CONCLUSION:The diagnosis of a hypoglycemia-producing pancreatic adenoma can be missed when an ultraspecific insulin assay is used. The direct measurement of proinsulin established the diagnosis in this case.

OBJECTIVE: To estimate the percentage of Mexican adults that may require lipid-lowering treatment according to National Cholesterol Education Program-III guidelines, using data from the National Health and Nutrition Survey 2006 (ENSANut 2006). MATERIAL AND METHODS: Information was obtained from 4 040 subjects aged 20 to 69 years, studied after a 9 to 12 hours fast. RESULTS: A cardiovascular risk equivalent was found in 13.8% and >2 risk factors were present in 31.5% of the population. LDL-C concentrations were above the treatment goal in 70% of the high-risk group and in 38.6% of subjects with >2 risk factors. Nearly 12 million Mexicans should be taught how to change their lifestyles and close to 8 million individuals require drug therapy to decrease their cardiovascular risk. CONCLUSIONS: Thirty percent of Mexican adults require some form of lipid-lowering treatment (lifestyle modifications in 36.25%, drug therapy in 24.19%).OBJETIVO: Calcular el porcentaje de adultos que requiere tratamiento hipolipemiante de acuerdo con las recomendaciones del Programa Nacional de Educación en Colesterol-III, usando los datos de la Encuesta Nacional de Salud y Nutrición 2006. MATERIAL Y MÉTODOS: Se incluyeron 4040 individuos con edad entre 20 y 69 años estudiados bajo un ayuno de 9 a 12 horas. RESULTADOS: Un equivalente de enfermedad cardiovascular fue identificado en 13.8% de los participantes. El 31.5% de la población tenía >2 factores de riesgo cardiovascular. La concentración de colesterol LDL estuvo arriba de la meta terapéutica en 70% de los casos con alto riesgo cardiovascular y en el 38.6% de los sujetos con >2 factores de riesgo. Cerca de 12 millones de mexicanos deben modificar su estilo de vida para reducir su concentración de colesterol LDL. Casi 8 millones califican para recibir tratamiento farmacológico. CONCLUSIONES: Una tercera parte de los adultos requiere alguna forma de tratamiento hipolipemiante (cambios en el estilo de vida: 36.25%, medicamentos: 24.19%).

OBJECTIVE:To evaluate the degree of control of metabolic goals in a group of very selected type 1 and 2 diabetic patients.METHODS:A cross-sectional and descriptive study was done. Patients were enrolled consecutively in the Diabetes Clinic in a tertiary-care hospital in México City during the period between april and july 2005. The population at this clinic is very selected as demonstrated by the fact that all type 2 diabetic patients were treated with drugs for diabetic control, including insulin in 43% of them. We used the goals recommended by the American Diabetes Association (ADA) as parameters to analyze and additionally included non-HDL cholesterol and the atherogenic index.RESULTS:A total of 530 patients were included; 468 (58.8% female) had type 2 diabetes, with an average age of 58.5 years; 62 (65% female) patients had type 1 diabetes, with an average age of 31.2 years. The mean HbA1c values were 10.2 +/- 2.8 and 9.0 +/- 2.4 in type 1 and type 2 diabetic patients, respectively. The proportion of diabetic type 1 and 2 patients reaching treatment goals were 12.9% and 23.7% for HbA1c (p=0.02), 82.2% and 57.2% for both systolic and diastolic blood pressure (p=0.0001), 75.8% and 49.3% for triglycerides (p=0.0001), 45.1% and 35.6% for LDL-c (p=0.16), 51.6% and 53.4% for HDL-c (p=0.79), 56.4% and 43.3% for non-HDL cholesterol (p=0.03) and 58.0% and 55.1% for atherogenic index (p=0.66), respectively. The proportion of patients reaching all the optimal treatment goals (non-HDL cholesterol, HbA1c, arterial blood pressure and triglycerides) was 6.4% for type 1 diabetic patients and 4.4% for type 2 patients (p=0.6). Factors associated with achieving goal values in a multiple regression analysis were drug treatment for high blood pressure, use of lipid lowering drugs, insulin use and a history of stroke.CONCLUSIONS:Our results are not comparable with other publications of series evaluating the same parameters in open populations. The results show that the degree of control of evaluated risk factors is not good, principally in the case of glucemic control; it is necessary to plan strategies that help to reach these goals in diabetic patients.

Background. Controversy exists regarding the optimal dose of radioiodine (1311) therapy in autoimmune hyperthyroidism (i.e., Graves' Disease).Methods. In order to evaluate the efficacy and safety of high dose 1311 therapy in autoimmune hyperthyroidism, a retrospective review of patients who received 1 therapy for Graves' disease from 1980 to 2000 in the Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City was carried out.Results. The study population consisted of 596 autoimmune hyperthyroid patients with a mean age of 35 years. The mean follow-up period was 10.31 +/- 2.37 years. Remission of hyperthyroidism occurred in 81.9%, persistent hyperthyroidism was recorded in 14.4% and recurrence in 3.7%. I-131 doses of 5-9 mCi (185-333 MBq) and >= 20 mCi (>= 740 MBq) were associated with remission rates of 65.5% and 87.7% respectively. Remission occurred earlier and more often with high doses of I-131. The high-dose group (20-30 mCi [740-1110 MBq]) had the lowest rate of persistence (9.7, 27.5 and 34.3%, for 20-30 [740-1110 MBq], 10-14 [370-518 MBq] and 5-9 [185-333 MBq] mCi, respectively p < 0.05) and hypothyroidism occurred earlier in this group (p = 0.05).Conclusions. Remission of autoimmune hyperthyroidism is more likely with doses of 20-30 mCi (740-1110 MBq). (c) 2007 IMSS. Published by Elsevier Inc.

Carlos A. Aguilar-Salinas, Rosalba Rojas, Clicerio Gonzalez-Villalpando, Francisco J. Gómez-Pérez, Roopa Mehta, Gustavo Olaiz, Juan A. Rull, and David Cox, Departamento de Endocrinología y Metabolismo del Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán," Mexico City, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, México, Centro de Estudios en Diabetes, The American British Coudray Hospital, México City, Perlegen Sciences, Mountain View, California, USA

OBJECTIVE:To identify the fasting plasma glucose (FPG) value with the best performance for detecting an abnormal response on the oral glucose tolerance test (OGTT) in patients at risk for having type 2 diabetes.METHODS:All patients who underwent a 2-hour OGTT during an 18-month period were included in this study. Pretest and posttest odds, likelihood ratios, and receiver operating characteristic curves were used to identify the FPG value most strongly associated with an abnormal result on the OGTT (either diabetes or impaired glucose tolerance [IGT]).RESULTS:Of the 1,371 patients who underwent an OGTT during the designated study period, 1,239 fulfilled the inclusion criteria. The prevalence of IGT was 25.34% (314 patients). Diabetes was diagnosed in 141 patients (11.38%). IGT was more commonly found in the FPG strata below 115 mg/dL; above this value, diabetes was more frequently diagnosed. In general, the percentage of cases of IGT increased progressively throughout the "normal" FPG range. The prevalence varied from 11.4% (in patients with FPG values <80 mg/dL) to 32% (in those with FPG levels from 95 to 99.9 mg/dL). FPG values between 95 and 99.9 mg/dL had a likelihood ratio of 2.1 for detecting an abnormal OGTT response, of 1.8 for detecting diabetes, and of 1.66 for detecting IGT. The odds ratio for detecting either IGT or diabetes was increased 2-fold by performing an OGTT. The FPG threshold with the best ability for detecting an abnormal response on the OGTT was 95 mg/dL (sensitivity of 0.72 and specificity of 0.65).CONCLUSION:In patients at risk for type 2 diabetes, the FPG cut point (95 mg/dL) most useful for detecting an abnormal OGTT response is included in the normal range of the FPG.

OBJECTIVE To report the diagnostic difficulties encountered in a case of glucagonoma. METHODS We provide a literature review and present the clinical findings, pertinent laboratory data, and results of related studies in a patient with a glucagonoma. RESULTS A 54-year-old-man, with no relevant history of endocrine disorders, presented to the hospital with a 5-year history of recurrent stomatitis and glossitis, a more recent weight loss of 11.5 kg, and recurrent pruritic maculae on the scalp in conjunction with raised erythematous maculae in the scrotal region and perineum that gradually migrated to the distal extremities, becoming bullous and painful. The patient was hospitalized, and because of the dermatologic findings suggestive of necrolytic migratory erythema, the presence of a glucagonoma was suspected. His blood glucose levels were in the normal range. Glucagon levels were found to be elevated, and imaging studies confirmed the presence of an enlarged mass in the pancreatic tail, without evidence of extension to surrounding structures. Liver metastatic lesions were also excluded. After surgical removal of the tumor, the skin and oral mucosal lesions disappeared spontaneously. The histologic appearance and immunohistochemical staining results confirmed the diagnosis of a glucagonoma. Subsequently, all related symptoms resolved, and the glucagon levels normalized. CONCLUSION The diagnosis of glucagonoma is often delayed. Clinicians should be aware of the unusual initial manifestations of this tumor and the potential for less than a full spectrum of the characteristic features of the glucagonoma syndrome.

OBJECTIVE - The National Cholesterol Education Program (NCEP) definition of the metabolic syndrome was modified to be described as a continuous variable and adapted to the characteristics of a Hispanic population.RESEARCH DESIGN AND METHODS - Age/sex population percentiles for every component of the NCEP criteria were included in this approach using population-based data from a Mexican nationwide survey (2,158 subjects). One point was given per decile for every component. The total number of points accumulated was used to classify subjects. The predictive power for incident diabetes was evaluated using the 7-year follow-up results of the Mexico City Diabetes Study.RESULTS - Our population-based method had a significantly better prognostic power compared with the original and the updated NCEP definitions (area under the receiver operating characteristic curve 0.746 vs. 0.697 and 0.723, respectively, P < 0.05). Using individuals with <= 1 component of the NCEP definition as reference, the odds ratio was greater in the upper quartile of the points scale (>= 39 points) (12.71 [95% CI 5.67-28.49]) compared with that calculated for the original (9.52 [4.69-19.31]) and the updated (11.14 [5.33-23.30]) NCEP criteria. The major advantage of our approach is the detection of subjects at the extremes of the range of diabetes risk and the ability to estimate this risk as a continuum.CONCLUSIONS - Our method adapts the NCEP criteria to the characteristics of a Hispanic population. It improves the predictive power of the NCEP criteria for future diabetes.

The metabolic syndrome integrates, in a single diagnosis, the manifestations of insulin resistance that may lead to increased cardiovascular morbidity and precedes type 2 diabetes. Here we discuss the strengths and limitations of the definitions of the metabolic syndrome and the epidemiology of the syndrome including information from non-Caucasian populations. The definitions proposed by the World Health Organization (WHO) and the National Cholesterol Education Program (NCEP) are the most frequently used. The relative risk of having long-term complications is greater for the WHO definition; this is explained by the inclusion of the insulin resistance criteria. The cut-off points used in these definitions should be, but are not, adjusted for ethnicity; as a result, in non-Caucasian subjects, there is lack of agreement among these criteria. In a Mexican population-based survey the prevalence was 13.61% using the WHO definition and 26.6% using the NCEP-III criteria. Cases identified by the WHO criteria had a more severe form of the disease. We propose that the metabolic syndrome should be viewed as a progressive long-term process that leads to major complications. Its definition should reflect the continuous nature of the disease; the categorical approach of the current criteria oversimplifies the complexity of the syndrome. The threshold for defining abnormality should be based on the associated risk of the identified phenotype. Refinement of the definition of both affected and nonaffected subjects is required. The available definitions include, in each of these categories, heterogeneous groups with a broad range of risk of future complications.