Management of type 2 diabetes: more evidence is required to address the clinical and contextual facets.

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. In summary, this manuscript highlights the key areas which require further work. If these issues are adequately addressed, the guidelines for the management of type 2 diabetes will be relevant and applicable to all diabetic groups.

HbA1c for the diagnosis of diabetes mellitus in a developing country. A position article.

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.

Beta-cell adenomas without hyperinsulinemia with use of highly specific insulin radioimmunoassays: case report and review of literature.

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.

[Degree of control of cardiovascular risk factors among a patient population with diabetes mellitus type 1 and 2]. / Grado de control de factores de riesgo cardiovascular en una población de pacientes con diabetes mellitus tipo 1 y 2 de difícil manejo.

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.

Grado de control de factores de riesgo cardiovascular en una población de pacientes con diabetes mellitus tipo 1 y 2 de difícil manejo / Degree of control of cardiovascular risk factors among a patient population with diabetes mellitus type 1 and 2

Objetivo: Evaluar la medida en que se alcanzan las metas de control en un grupo de pacientes seleccionados con diabetes tipo 1 o 2. Métodos: Estudio transversal y descriptivo en el que se incluyeron pacientes atendidos de manera consecutiva en la Consulta Externa de Diabetes del Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán entre abril y julio de 2005; la población seleccionada era de difícil control metabólico; todos los pacientes con diabetes mellitus tipo 2 recibían fármacos para controlar la glucemia, incluyendo insulina en 43% de ellos. Analizamos los criterios de control recomendados por la Asociación Americana de Diabetes, las cifras de colesterol no-HDL y el índice aterogénico. Resultados: Se incluyeron 530 pacientes: 468 (mujeres 58.8%) tenían diabetes tipo 2, con edad promedio de 58.5 años, y 62 (mujeres 65%) tenían diabetes tipo 1, con edad promedio de 31.2 años. El valor promedio de HbA1c fue de 10.2±2.8 y 9.0±2.4 para diabéticos tipo 1 y tipo 2. Las proporciones de pacientes con diabetes tipos 1 y 2 dentro de las metas de tratamiento fueron de 12.9 y 23.7% para HbA1c (p=0.02), 82.2 y 57.2% para presión arterial sistólica y diastólica (p=0.0001), 75.8 y 49.3% para triglicéridos (p=0.0001), 45.1 y 35.6% para c-LDL (p=0.16), 51.6 y 53.4% para c-HDL (p= 0.79), 56.4 y 43.3% para c-no-HDL (p=0.03) y 58.0% versus 55.1% para índice aterogénico (p=0.66). La proporción de pacientes que alcanzaron metas de colesterol no-HDL, HbA1c, presión arterial y triglicéridos fue de 6.4% para diabéticos tipo 1 y de 4.4% para diabéticos tipo 2 (p=0.6). En el análisis de regresión logística múltiple, las variables asociadas con mayor probabilidad de alcanzar las metas de control fueron el tratamiento con antihipertensivos, el uso de hipolipemiantes, de insulina y el antecedente de enfermedad vascular cerebral. Conclusiones: Si bien nuestros resultados no pueden ser directamente comparables con los publicados en otras series en poblaciones abiertas, muestran que el grado de control de los factores de riesgo considerados no es aceptable, sobre todo en los niveles de glucemia; es necesario implementar programas que ayuden a cumplir estas metas en pacientes diabéticos.

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.

Analysis of fasting plasma glucose values for optimal detection of abnormal responses on the oral glucose tolerance test in at-risk study subjects.

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.

Radioiodine treatment in autoimmune hyperthyroidism: analysis of outcomes in relation to dosage.

BACKGROUND: Controversy exists regarding the optimal dose of radioiodine ((131)I) therapy in autoimmune hyperthyroidism (i.e., Graves' Disease). METHODS: In order to evaluate the efficacy and safety of high dose (131)I therapy in autoimmune hyperthyroidism, a retrospective review of patients who received (131)I therapy for Graves' disease from 1980 to 2000 in the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, 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%. (131)I doses of 5-9 mCi (185-333 MBq) and > or =20 mCi (> or =740 MBq) were associated with remission rates of 65.5% and 87.7% respectively. Remission occurred earlier and more often with high doses of (131)I. 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).

Design and validation of a population-based definition of the metabolic 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 /=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.

Genetic heterogeneity of autosomal dominant hypercholesterolemia in Mexico.

BACKGROUND: Familial hypercholesterolemia (FH) and familial defective apolipoprotein B-100 (FDB) are relatively common lipid disorders caused by mutations of the low-density lipoprotein receptor (LDLR) and apolipoprotein B (apoB) genes, respectively. A third locus on chromosome 1p34.1-p32 was recently linked to FH and the responsible gene has been identified [protein convertase subtilisin/kexin type 9 (PCSK9)]. METHODS: We assessed the contribution of the LDLR, apoB, and PCSK9 genes as cause of FH in Mexico. Forty six unrelated probands, as well as 68 affected and 60 healthy relatives, were included. RESULTS: All index cases were diagnosed as having heterozygous autosomal dominant FH. Seventeen of the 46 index cases had LDLR gene mutations, four of which were novel (Fs92ter108, C268R, Q718X, and Fs736ter743); and only one patient had an apoB mutation (R3500Q). We sequenced the PCSK9 gene in the remainder of the 28 probands with no identified LDLR or APOB gene defects; however, no PCSK9 mutations were found, including one large kindred with positive linkage to the 1p34.1-32 locus (multipoint LOD score of 3.3) and two small pedigrees. Linkage was excluded from these three loci in at least four kindreds suggesting that other yet uncharacterized genes are involved. CONCLUSIONS: Our results underline substantial genetic heterogeneity for FH in the Mexican population.

Applicability of the National Cholesterol Education Program III (NCEP-III) guidelines for treatment of dyslipidemia in a non-Caucasian population: a Mexican nation-wide survey.

We assessed the impact of the NCEP-III recommendations in a population-based, nation-wide Mexican survey. Information was obtained from 15,607 subjects aged 20 to 69 years. In this report, only samples obtained after a 9 to 12 hours fast are included (2,201 cases). A cardiovascular risk equivalent was found in 10.5% and > or = 2 risk factors were present in 41.7% of the population. In 10% of cases, the LDL-C concentration was high enough to be an indication for a lipid-lowering drug (> 160 mg/dL), independent of the presence of risk factors. A quarter of the population was eligible for some form of treatment (lifestyle modifications in 15.9%, drug therapy in an additional 11.7%). Among cases with > or = 2 risk factors, a small percentage (1.8%) were identified as having a 10 year-risk > 20% and 86.3% were considered as having a 10 year-risk < 10%. The majority of the metabolic syndrome cases (84%) were identified as low-risk subjects. As a result, only 17.6% of them qualified for drug-based LDL-C lowering. Our data helps to estimate of the magnitude of the burden imposed on the Mexican health system, of lowering LDL-C for cardiovascular prevention. If we apply our results to the 2,000 Mexican population census more than 5.8 million cases nationwide may require LDL lowering drug therapy following the NCEP-III criteria.

Epidemiology of type 2 diabetes in Mexico.

The epidemiology of diabetes in Mexico is reviewed. In less than four decades, diabetes has become the main health problem in Mexico. It is the principal cause of death in women and the second among men since the year 2000. It is the primary cause of premature retirement, blindness, and kidney failure. By the year 2025, close to 11.7 million Mexicans are expected to be diagnosed with diabetes. In the year 2000, diabetes was the 11th most frequent cause of hospitalization but the second most common cause of hospital mortality. The number of cases reported in children has also increased since 1995. The results of population-based, nationwide surveys have detected a 25% increment over a 7-year period. Fourteen percent of people with diabetes are <40 years of age, and a large proportion of patients have other conditions that determine the appearance of macrovascular complications and kidney failure. In addition, many cases do not reach treatment goals. In conclusion, the growing number of cases and the significant health burden imposed on affected subjects makes diabetes a disease that needs to be prevented. Well-planned strategies are urgently needed to modify the lifestyle of the population and to increase their physical activity. In addition, an enormous effort will be required to educate the population and physicians to improve the diagnosis and treatment of patients with diabetes.

The metabolic syndrome: a concept hard to define.

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.

Applicability of the National Cholesterol Education Program III (NCEP-III) Guidelines for treatment of dyslipidemia in a non-Caucasian population: A Mexican Nation-Wide Survey / Aplicabilidad del III Programa Nacional de Educación en Colesterol (NCEP-III). Guías para el tratamiento de la dislipidemia en una población no caucásica: Un estudio en toda la nación mexicana

We assessed the impact of the NCEP-III recommendations in a population-based, nation-wide Mexican survey. Information was obtained from 15,607 subjects aged 20 to 69 years. In this report, only samples obtained after a 9 to 12 hours fast are included (2,201 cases). A cardiovascular risk equivalent was found in 10.5% and > 2 risk factors were present in 41.7% of the population. In 10% of cases, the LDL-C concentration was high enough to be an indication for a lipid-lowering drug (> 160 mg/dL), independent of the presence of risk factors. A quarter of the population was eligible for some form of treatment (lifestyle modifications in 15.9%, drug therapy in an additional 11.7%). Among cases with > 2 risk factors, a small percentage (1.8%) were identified as having a 10 year-risk > 20% and 86.3% were considered as having alO year-risk < 10%. The majority of the metabolic syndrome cases (84%) were identified as low-risk subjects. As a result, only 17.6% of them qualified for drug-based LDL-C lowering. Our data helps to estimate of the magnitude of the burden imposed on the Mexican health system, of lowering LDL-C for cardiovascular prevention. If we apply our results to the 2,000 Mexican population census more than 5.8 million cases nationwide may require LDL lowering drug therapy following the NCEP-III criteria.

Evaluamos el impacto de las recomendaciones del Programa Nacional de Educación en Colesterol (NCEP-III) en muestra poblacíonal. La información proviene de 2,201 sujetos de 20 a 69 años cuyas muestras se obtuvieron después de un ayuno de 9 a 12 horas. Una condición con riesgo cardiovascular equivalente al de la cardiopatía isquémica se encontró en 10.5%; > 2 factores de riesgo se encontraron en 41.7%. El colesterol LDL (LDL-C) fue suficientemente alto (> 160 mg/dL) para indicarse tratamiento hipolipemiante con medicamentos, en ausencia de otros factores de riesgo en 10% de los participantes. El 25% de la población calificó para recibir tratamiento hipolipemiante (cambios del estilo de vida 15.9% y tratamiento farmacológico en 11.7%). En casos con > 2 factores de riesgo, un pequeño porcentaje (1.8%) fue identificado con riesgo mayor a > 20% de tener un evento cardiovascular a 10 años; 86.3% fue identificado con bajo riesgo (< 10% a 10 años). La mayoría de los casos con síndrome metabólíco (84%) fueron identificados en el grupo de bajo riesgo. Como resultado, sólo 17.6% de ellos calificó para disminuir su LDL-C con medicamentos. Nuestros datos demuestran el reto que representa la prevención de complicaciones cardiovasculares por medio de la reducción de la concentración del LDL-C. Extrapolando nuestros datos al censo 2000, más de 5.8 millones de mexicanos califican para recibir tratamiento farmacológico de acuerdo con los criterios del NCEP-III.

Psychosocial factors associated with poor diabetes self-care management in a specialized center in Mexico City.

To examine the relationship between demographic, clinical and psychosocial variables and diabetes self-care management in Mexican type 2 diabetic patients. Cross-sectional study of 176 consecutive patients with type 2 diabetes aged 30-75 years, attending a tertiary health-care center in Mexico City. A brief medical history and previously validated questionnaires were completed. The study group consisted of 64 males/112 females, aged 55 +/- 11 years, mean diabetes duration of 12 +/- 8 years and HbA1c of 9.0 +/- 2.0%, 78.4% reported following the correct dose of diabetes pills or insulin, 58% ate the recommended food portions, and 44.3% did exercise three or more times per week. A good adherence to these three recommendations was observed in only 26.1% of the patients. These patients considered as a group were characterized by a greater knowledge about the disease (P < 0.00001), regular home blood glucose monitoring (P < 0.01), an inner perception of better diabetes control (P = 0.007), good health (P = 0.004) and better communication with their physician (P < 0.02). A poor adherence to two or the three main diabetes care recommendations was associated with a depressive state (OR 2.38, 95% CI 1.1-4.9, P < 0.01) and a history of excessive alcohol intake (OR 4.03, 95% CI 1.1-21.0, P = 0.03). Poor adherence to standard diabetes care recommendations is frequently observed in patients with type 2 diabetes attending a specialized health care center in Mexico City. Depression must be identified and treated effectively.

Familial combined hyperlipidemia: controversial aspects of its diagnosis and pathogenesis.

Familial combined hyperlipidemia is the most frequent cause of primary dyslipidemia in Mexico. Its manifestations include hypercholesterolemia, hypertriglyceridemia, or a combination of both. Despite its high frequency, a proper diagnosis is rarely made. Assessment of the lipid profiles of at least three first-degree relatives is necessary. The diagnosis of familial combined hyperlipidemia in a family not only leads to the identification of other affected family members but, more important, allows cardiovascular risk stratification of those affected. Prospective studies have confirmed the atherogenicity of the disease. A critical review of the current literature in this field is presented in this article. Although three screenings of the genome have been completed, the genes responsible for this disorder have not been identified. Limitations with respect to the characterization of affected subjects and the heterogeneity of the disease are among possible explanations. However, familial combined hyperlipidemia, because of its high prevalence, must be given greater priority. It represents a great challenge for physicians involved in the treatment of dyslipidemic patients.

[Epidemiology of the metabolic abnormalities in patients with HIV infections]. / Epidemiología de las anormalidades metabólicas en pacientes con infección por VIH.

The epidemiology of the metabolic complications of antiretroviral agents is discussed here. Contradictory findings are common in this field due to methodological problems. The prevalence depends on the activity of the infection and on the type of treatment. Before treatment, the most common lipid abnormalities are low HDL-cholesterol (< 35 mg/dL, 25.5%) and hypertriglyceridemia (> 200 mg/dL, 15.2%). The prevalence of hypercholesterolemia is 3 times higher during treatment, especially if a protease inhibitor (IP) is used. Hypertension has been described as not common because high thresholds have been used in previous reports. Diabetes has been found in 6-7%. Similar prevalences were found in a retrolective study including 464 cases. Before treatment, hypertriglyceridemia was found mainly in cases with a body weight below normal; the opposite trend was found after treatment. After one year of treatment the prevalence of hypertension (> or = 130/85), hypertriglyceridemia (> or = 150), hypercholesterolemia (> 200 mg/dL), diabetes and low HDL cholesterol (< 35 mg/dL) were 38.5, 71.1, 47.6, 2.2% and 36%, respectively. The frequencies were even greater in IP-treated cases. Smoking was a frequent modifiable risk factor in this group (42.3%). Thus, many aspects remain to be explored; the follow-up of multicentric cohorts will provide evidence for preventive actions. In Mexican HIV infected patients, hypertriglyceridemia, arterial hypertension and smoking are the most common cardiovascular risk factors.

Epidemiología de las anormalidades metabólicas en pacientes con infección por VIH / Epidemiology of the metabolic abnormalitis in patients with HIV infections

Analizamos la epidemiología de las complicaciones metabólicas del tratamiento antirretroviral. Resultan de la interacción de factores del individuo y de los efectos del tratamiento. Resultados divergentes son frecuentes en este campo debido a limitaciones metodológicas. La prevalencia depende de la actividad de la infección y del tipo de tratamiento. En casos no tratados, la dislipidemia más común es colesterol-HDL bajo (< 35 mg/dL, 25.5%), seguido de la hipertrigliceridemia (> 200 mg/dL, 15.2%). La prevalencia de hipercolesterolemia es tres veces mayor en los casos tratados, en especial cuando se incluye inhibidores de proteasa (IPs). La prevalencia de hipertensión se ha reportado como baja debido al uso de definiciones con puntos de corte muy altos. La diabetes se observa en 6-7% de los casos. Prevalencias similares se encontraron en un estudio retrolectivo realizado en 464 casos. En individuos no tratados, la hipertrigliceridemia se observó preferentemente en sujetos por debajo de su peso ideal; lo opuesto se observó después del tratamiento. Después de un año, las prevalencias de hipertensión (≥ 130/85), hipertrigliceridemia (≥ 150), hipercolesterolemia (> 200 mg/dL), diabetes y colesterol HDL bajo (< 35 mg/dL) fueron 38.5, 71.1, 47.6, 2.2 y 36%. Las prevalencias fueron aún mayores en los casos con un IP. El tabaquismo fue otro factor de riesgo modificable frecuente (42.3%). Así, son muchos los aspectos que permanecen por ser analizados; se requieren de cohortes prospectivas cuyo análisis sirva para el diseño de estrategias preventivas. En población mexicana la hipertrigliceridemia, la hipertensión y el consumo de tabaco son los factores de riesgo cardiovascular más frecuentes en los pacientes con VIH.

The epidemiology of the metabolic complications of antiretroviral agents is discussed here. Contradictory findings are common in this field due to methodological problems.The prevalence depends on the activitiy of the infection and on the type of treatment. Before treatment, the most common lipid abnormalities are low HDL-cholesterol (< 35 mg/dL, 25.5%) and hypertriglyceridemia (> 200 mg/dL, 15.2%). The prevalence of hypercholesterolemia is 3 times higher during treatment, espacially if a protease inhibitor (IP) is used. Hypertension has been described as not common because high thresholds have been used in previous reports. Diabetes has been found in 6-7%. Similar prevalences were found in a retrolective study including 464 cases. Before treatment, hypertriglyceridemia was found mainly in cases with a body weight below normal; the opposite trend was found after treatment. After one year of treatment the prevalence of hypertension (≥ 130/85), hypertriglyceridemia (≥ 150), hypercholesterolemia (> 200 mg/dL), diabetes and low HDL cholesterol (< 35 mg/dL) were 38.5, 71.1, 47.6, 2.2% and 36%, respectively. The frequencies were even greater in IP-treated cases. Smoking was a frequent modifiable risk factor in this group (42.3%). Thus, many aspects remain to be explored; the follow-up of multicentric cohorts will provide evidence for preventive actions. In Mexican HIV infected patients, hypertriglyceridemia, arterial hypertension and smoking are the most common cardiovascular risk factors.

High prevalence of metabolic syndrome in Mexico.

BACKGROUND: Our objective was to describe the prevalence of the metabolic syndrome using World Health Organization (WHO) and National Cholesterol Education Program (NCEP-III) definitions in a population-based survey. METHODS: We performed an analysis of data from a Mexican nationwide, population-based study. The population was composed of 2,158 men and women aged 20-69 years sampled after a 9-12 h fasting period. Prevalence of the metabolic syndrome as defined by the NCEP-III definition and WHO criteria was estimated and case characteristics were assessed. RESULTS: Age-adjusted prevalence was 13.61% for WHO criteria and 26.6% for the NCEP-III definition. Prevalence was 9.2 and 21.4%, respectively, in subjects without diabetes. Thirty five percent of affected cases were <40 years of age. In addition to criteria used for diagnosis, ca. 90% were either overweight or obese. In cases detected using WHO criteria, antihypertensive treatment or blood pressure reading >140/90 was found in 61.8%. The proportion of subjects who qualified for hypolipemiant treatment was lower: lifestyle modifications were needed in 42.1% and drug therapy was required in 18.9%. The same trends were found for cases detected using the NCEP definition. CONCLUSIONS: Prevalence of the metabolic syndrome in Mexico is high. A large proportion of affected cases qualify for preventive actions for complications of the metabolic syndrome (i.e., weight loss, antihypertensive or hypolipemiant treatment). These results provide data for planning therapeutic programs for Mexican patients with the metabolic syndrome.

Localization of parathyroid adenomas by (99m)Tc-sestamibi scanning: upper neck versus lower neck lesions.

OBJECTIVE: To assess the diagnostic properties of (99m)Tc-sestamibi scanning (dual-phase technique) in patients with primary hyperparathyroidism and to establish the overall efficacy of this imaging technique for localization of an adenoma. METHODS: The medical records of all 131 patients who underwent parathyroid scanning in a tertiary care center between January 1997 and December 2002 were reviewed. The surgical findings were used as the "gold standard" for the diagnosis of parathyroid pathologic conditions. RESULTS: Primary hyperparathyroidism was diagnosed in 87 of the 131 patients (66.4%); of these, 76 underwent surgical treatment. In 44 patients, sestamibi scanning was also done for conditions other than primary hyperparathyroidism. (99m)Tc-sestamibi scanning had a sensitivity of 79.1%, a specificity of 86.7%, a positive predictive value of 88.3%, a false-positive rate of 11.6%, and a false-negative rate of 23.3% for the diagnosis of parathyroid adenoma. Despite the apparent high sensitivity of this scanning technique, only 58.2% of the adenomas were found intra-operatively at the location predicted by the scan. Lesions in the upper neck area were missed more frequently by sestamibi scanning than were those in the lower neck area (13 of 32 versus 1 of 35, respectively) (P<0.05). CONCLUSION: Preoperative localization of parathyroid adenomas with use of (99m)Tc-sestamibi scanning showed a limited capacity to reveal their precise location. Thus, such scans must be complemented with other studies, such as intraoperative ultrasonography and rapid parathyroid hormone assay, to ensure a successful excision if a limited surgical procedure is planned.

[The metabolic syndrome: a concept in evolution]. / El síndrome metabólico: un concepto en evolución.

The concept metabolic syndrome intends to incorporate in a single disorder all biologic consequences of insulin resistance and associated conditions. The objective of this paper was to discuss strengths and limitations of current definitions of the metabolic syndrome, its epidemiology, and its association with non-alcoholic steatohepatitis (NASH). Definitions proposed by the World Health Organization (WHO) and the National Cholesterol Education Program (NCEP) are specific but possess low sensitivity for detecting insulin resistance. 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. For example, in a Mexican population-based survey prevalence was 13.61% using the WHO definition and 26.6% employing NCEP-III criteria. Cases identified with WHO criteria have a more severe form of the disease. NASH is the most common cause of abnormal levels of serum aminotransferases. It shares some aspects of its pathophysiology with the metabolic syndrome and its prevalence is higher among cases with metabolic syndrome compared to with general population. NASH appears to be the hepatic manifestation of the metabolic syndrome.