Ramón Alberto Rascón-Pacheco

Infection and death from influenza A H1N1 virus in Mexico: a retrospective analysis

BACKGROUND In April, 2009, the first cases of influenza A H1N1 were registered in Mexico and associated with an unexpected number of deaths. We report the timing and spread of H1N1 in cases, and explore protective and risk factors for infection, severe disease, and death. METHODS We analysed information gathered by the influenza surveillance system from April 28 to July 31, 2009, for patients with influenza-like illness who attended clinics that were part of the Mexican Institute for Social Security network. We calculated odds ratios (ORs) to compare risks of testing positive for H1N1 in those with influenza-like illness at clinic visits, the risk of admission for laboratory-confirmed cases of H1N1, and of death for inpatients according to demographic characteristics, clinical symptoms, seasonal influenza vaccine status, and elapsed time from symptom onset to admission. FINDINGS By July 31, 63 479 cases of influenza-like illness were reported; 6945 (11%) cases of H1N1 were confirmed, 6407 (92%) were outpatients, 475 (7%) were admitted and survived, and 63 (<1%) died. Those aged 10-39 years were most affected (3922 [56%]). Mortality rates showed a J-shaped curve, with greatest risk in those aged 70 years and older (10.3%). Risk of infection was lowered in those who had been vaccinated for seasonal influenza (OR 0.65 [95% CI 0.55-0.77]). Delayed admission (1.19 [1.11-1.28] per day) and presence of chronic diseases (6.1 [2.37-15.99]) were associated with increased risk of dying. INTERPRETATION Risk communication and hospital preparedness are key factors to reduce mortality from H1N1 infection. Protective effects of seasonal influenza vaccination for the virus need to be investigated. FUNDING None.

Prediabetes and its relationship with obesity in Mexican adults: The Mexican Diabetes Prevention (MexDiab) Study.

BACKGROUND Epidemiological data on impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) based on a representative Mexican sample are not available; thus, the objectives of this study were to determine the prevalence and distribution of IFG and IGT, and to establish its relationship with obesity in Mexican adults. METHODS We performed a cross-sectional population-based study on a representative sample of Mexican adults aged 30 to 65 years. Anthropometric measurements of obesity that included waist circumference (WC) and total body fat percentage were collected and the body mass index calculated. All subjects also underwent an oral glucose tolerance test. Diagnosis of glucose metabolism disorders was based on criteria of the American Diabetes Association. RESULTS Prevalence of IFG, IGT, and IFG+IGT was 24.6%, 8.3%, and 10.3%, respectively. The age-adjusted prevalence of IFG (49.5% and 50.5%), IGT (49.1% and 50.9%), and IFG+IGT (57.3% and 42.7%) was similar in men and women. Prevalence of obesity was 45.9% with predominance in women (48.8% versus 42.1%, P = 0.01). A total of 394 (31.0%) individuals were overweight. Among the 550 prediabetic normal weight subjects, 70 (22.4%), 15 (14.2%), and 7 (5.3%) had IFG, IGT, or IFG+IGT. The odds ratio (OR) between WC and IFG (OR 3.1, CI(95%) 1.4-9.7), IGT (OR 3.2, CI(95%) 1.2-9.1), and IFG+IGT (OR 2.8, CI(95%) 1.3-8.2) was higher than the OR of other measurements of obesity. CONCLUSIONS Prevalence of prediabetes in the Mexican adult population is high. WC is the measure of obesity more strongly associated with metabolic glucose disorders. A high proportion of subjects with normal weight exhibit prediabetes.

Distribution of the homeostasis model assessment of insulin resistance in Mexican children and adolescents

OBJECTIVE Several cutoff points of the homeostasis model assessment of insulin resistance (HOMA-IR; varying from 2.5 to 4.0) have been suggested for diagnosing IR in youth. In this study, we determined the distribution of the HOMA-IR in Mexican children and adolescents. DESIGN AND METHODS A total of 6132 children and adolescents from San Luis Potosi, León, Queretaro, and Durango, which are cities in central and northern Mexico, were enrolled in a population-based cross-sectional study. Eligible participants were apparently healthy children and adolescents aged 6-18 years. Pregnancy and the presence of chronic illnesses were exclusion criteria. RESULTS A total of 3701 (60.3%) girls and 2431 (39.7%) boys were included in this study. In the overall population, the mean body mass index, insulin levels, and fasting glucose levels were 21.8±1.3 kg/m(2), 7.1±3.2 μU/ml, and 86.2±10.0 mg/dl respectively. The concentrations of insulin and fasting glucose gradually increased from 6 to 12 years of age, whereas the concentrations tended to plateau in the 13- to 18-year-old population. The absolute mean of the HOMA-IR was 2.89±0.7. The HOMA-IR gradually increased with age and reached a plateau at 13 years of age. CONCLUSIONS Because the insulin concentrations, glucose levels, and HOMA-IR exhibited a gradual increase with age that was not related to obesity, our results suggested that the evaluation of IR in children should be based on percentiles of the HOMA-IR rather than a dichotomous value derived from a single cutoff point.

Prevalencia de factores de riesgo de enfermedad coronaria en trabajadores del Hospital General de México

Objetivo. Conocer la prevalencia de algunos factores de riesgo coronario en trabajadores de una institucion de salud. Material y metodos. De 1993 a 1995 se evaluaron 2 228 trabajadores del Hospital General de Mexico, 1 531 mujeres (68.7%) y 697 hombres (31.2%) con edades entre 16 a 65 anos, y se les clasifico por areas de trabajo: en Intendencia hubo 477 participantes (21.4%); en Administracion, 697 (31.2%); en Personal Medico, 495 (22.2%), y en Enfermeria, 559 (25.0%). Se les practico historia clinica, mediciones antropometricas y determinacion de glucosa, colesterol total, LDL, HDL y trigliceridos. Resultados. Trescientos sesenta y siete sujetos (14.9%) tenian colesterol por arriba de 240 mg/dl, con valores altos en las mujeres del area administrativa (17.1%) y en los hombres del departamento de enfermeria (26%) que presento la mayor tendencia (26%). Se encontraron niveles de trigliceridos por arriba de los 200 mg/dl en 471 personas (19.1%); obesidad, en 329 (13.5%); hipertension arterial, en 549 sujetos (22.2%), y tabaquismo positivo, en 32% de los trabajadores. La prevalencia de diabetes mellitus fue de 6.24%. Conclusiones. Se confirma la elevada prevalencia de factores de riesgo de enfermedad cardiovascular entre los trabajadores del Hospital General de Mexico, factores que en muchos casos son modificables, lo que confiere la posibilidad de realizar acciones preventivas.

Cardiovascular Risk Factors and Acculturation in Yaquis and Tepehuanos Indians from Mexico

BACKGROUND Cardiovascular (CV) risk factors are influenced by behavioral, cultural, and social factors, suggesting that acculturation plays a significant role in the emergency and growth of chronic disease. The objective of this study was to determine the relation between CV risk factors and the main components of acculturation, in Yaquis and Tepehuanos Indians from Mexico. METHODS This was a cross-sectional population-based study in Yaquis and Tepehuanos communities from the Yaqui Valley in Sonora and the Sierra Madre Occidental Mountains in Durango, in northwest Mexico. Acculturation status is different in both ethnic groups, with Tepehuanos living in small and remote communities retaining their traditional lifestyle and Yaquis living in well-communicated communities that have assumed Westernized lifestyles. RESULTS A total of 278 indigenous (120 Tepehuanos and 158 Yaquis) were randomly enrolled. Prevalence of obesity (48.1 and 6.7%, p <0.001), diabetes (18.3 and 0.83%, p <0.001), hypertriglyceridemia (43.0 and 15.0%, p <0.001), alcohol consumption (46.8 and 26.6%, p >0.001), and smoking (29.7 and 15.0%, p = 0.006) were significantly higher in Yaquis Indians. High blood pressure (6.3 and 3.3%, p = 0.40) and low HDL-cholesterol (42.4 and 34.2%, p = 0.22) were similar between Yaquis and Tepehuanos. Multivariate regression analysis adjusted by sex and age showed a significant association between calorie intake from saturated fat, but not other nutrients of customary diet, with hyperglycemia (OR 7.4, 95% CI 2.6-20.1), hypertriglyceridemia (OR 3.1, 95% CI 1.5-6.3), and obesity (OR 3.4, 95% CI 1.6-10.1). CONCLUSIONS Among the components of acculturation, intake of saturated fat is the most strongly associated with the development of CV risk factors.

Time-trends and causes of infant, neonatal and postneonatal mortality in Mexico, 1980-1990

OBJECTIVE This article analyzes the time-trends and causes of infant, neonatal, and postneonatal mortality in Mexico during the 1980s. MATERIAL AND METHODS Data on infant deaths came from yearly tabulations (1980 to 1990) published by the Mexican government. Time-trends of mortality rates were determined by simple linear regression models. The parallelism test was performed for evaluating similarities in trends in neonatal and postneonatal mortality rates by causes. RESULTS During the 1980s, infant mortality rates in Mexico declined from 40.4 to 31.1/1000 (beta = -0.791). Postneonatal mortality rates showed a strong decrease (beta = -0.892), while neonatal mortality rates were almost stationary (beta = 0.089). Significant rate decreases were observed for intestinal infections, Pneumonia and influenza and All other causes while Certain perinatal problems, Congenital defects and Nutritional deficiencies increased. No changes were observed in Acute respiratory infections. The neonatal proportional mortality showed an incremental trend accounting for 37.6% in 1980 and ascending to 48.8% in 1990 of the mortality in the first year of life. CONCLUSIONS This analysis indicates that the reduction in infant mortality in Mexico during the 1980s was due to declining postneonatal mortality while neonatal mortality rates remain almost unchanged.

Dietary factors related to the increase of cardiovascular risk factors in traditional Tepehuanos communities from Mexico. A 10 year follow-up study

BACKGROUND AND AIMS Tepehuanos Indians, a traditional Mexican ethnic group, followed a vegetarian diet exhibiting a low prevalence of obesity and the absence of diabetes. However, from the year 2000 the traditional diet of the Tepehuanos was modified by the introduction of western food. In this study we examine the changes in their customary diet and its impact on the prevalence of cardiovascular risk factors in this group. METHODS AND RESULTS Individuals from 12 Tepehuanos communities were randomly enrolled during 1995-1996 and 2006-2007. Using a 64-item semiquantitative food frequency questionnaire macronutrient intakes were calculated from values of Mexican food-composition tables. Cardiovascular risk factors such as obesity, hypertension, hyperglycemia and dyslipidemia were determined. The median (25, 75 percentile) of total caloric intake (1476 [1083, 1842]-2100 [1366, 2680]kcal/day, p<0.001) as well as the percentage of energy consumed from saturated fat (3.0 [2.7,4.1]-7.2 [3.9,7.4], p<0.0001) and protein (8.2 [7.8,8.9]-16.8 [16.3,17.1], p<0.0001) increased, whereas the percentage of total calorie intake from carbohydrates (66.4 [61.3,69.5]-61.3 [61,68.8], p<0.0001), polyunsaturated fat (11.2 [10.3,12.1]-4.0 [3.9,4.3], p<0.0001), and the polyunsaturated:saturated fat ratio (3.84-0.53%, p<0.0001) decreased during the period of study. The prevalence of obesity (11.1-21.9%, p=0.04), impaired fasting glucose (5.9-14.9%, p=0.04), diabetes (0.0-0.88%, p=0.48), hypertension (1.7-3.4%, p=0.43), triglycerides (2.6-16.7%, p=0.0006), and low HDL-cholesterol (10.2-71.1%, p<0.0001) increased. CONCLUSIONS Changes in the customary diet introduced in the Tepehuanos communities are related to the increase of cardiovascular risk factors.

La mortalidad infantil por malformaciones congénitas en México: un problema de oportunidad y acceso al tratamiento

OBJETIVOS: Caracterizar el comportamiento del Sistema Nacional de Salud (SNS) de Mexico en la tarea de reducir el numero de muertes por malformaciones congenitas mediante el analisis de la tendencia de las tasas de mortalidad infantil especificas por esas afecciones. METODOS: Analisis de series de tiempos de las defunciones de ninos y ninas menores de 1 ano entre 1980 y 2005, segun las bases de datos nacionales anuales de mortalidad de la Secretaria de Salud de Mexico. Se calcularon las tasas de mortalidad infantil especificas (TMIe) por malformaciones congenitas graves mas frecuentes en Mexico: defectos del tubo neural, hernia diafragmatica congenita, exonfalos (onfalocele y gastrosquisis) y malformaciones cardiacas y del tubo digestivo, agrupadas segun el grado de urgencia y de sofisticacion tecnologica que demanda su tratamiento y el desenlace mas frecuente. RESULTADOS: Entre 1980 y 2005, la tasa de mortalidad infantil en Mexico descendio de 40,7 a 16,9 por 1 000 nacimientos (β = -0,86; P < 0,001); en cambio, la tasa de mortalidad especifica por malformaciones congenitas crecio de 2,2 a 3,5 por 1 000 nacimientos (β = 0,05; P < 0,001). La hipertrofia pilorica y la atresia anorrectal, malformaciones con buen pronostico y tratamiento programable en unidades con equipamiento basico, fueron las unicas que mostraron una tendencia descendente en su TMIe (β = -0,01 a -0,09; P < 0,001), mientras que las que requieren tratamiento urgente en unidades especializadas mostraron TMIe crecientes (β = 0,03 a 0,05; P < 0,001). CONCLUSIONES: El desarrollo del SNS de Mexico entre 1980 y 2005 no se ha traducido en una reduccion en la mortalidad por malformaciones congenitas; esta ineficacia fue mas notoria en las enfermedades cuyo tratamiento es urgente y requiere tecnologia sofisticada.

Evaluation of the impact on non-communicable chronic diseases of a major integrated primary health care program in Mexico.

BACKGROUND Primary health care is the best framework for implementing actions for the prevention and control of non-communicable diseases at an appropriate scale. In 2002, the Mexican Institute for Social Security (IMSS), which provides health care to half of the Mexican population, implemented a primary care-based integrated program that included the improvement of the family health care practice and a preventive strategy called PREVENIMSS, to reduce the burden of disease. OBJECTIVE To asess the impact of this program on selected non-communicable chronic diseases. METHODS Morbidity and mortality were compared before and after implementation of the program and time trends in IMSS affiliates and non-affiliates using the difference-in-differences (DD) method. RESULTS Incidence rates of diabetes and hypertension increased whereas those of cervical cancer, breast cancer and other cerebrovascular diseases decreased from 2000 to 2013. The DD in mortality rates, expressed per 100000 persons, showed a decrease of 49.4 for diabetes mellitus, 9.1 for hypertensive disease, 42.9 for ischemic heart disease, 17.4 for cerebrovascular disease, 7.5 for cervical cancer and 5.8 for breast cancer. CONCLUSIONS The reductions in mortality rates could be explained by both changes in incidence rates and changes in case fatality rates associated with early detection and treatment. These initial findings can be interpreted as the potential impact of integrated programs based on primary health care in a developing country.

Sistema de vigilancia epidemiológica para el paciente diabético; el uso de tecnología computacional en la calidad de la atención médica

OBJETIVO: Presentar un instrumento que permita llevar a cabo la vigilancia epidemiologica y evaluar la calidad de la atencion a la diabetes mellitus en el primer nivel de atencion. MATERIAL Y METODOS: Este estudio se realizo del 1 de enero de 1998 al 30 de junio de 1999, en la Unidad de Investigacion Epidemiologica y en Servicios de Salud, del Instituto Mexicano del Seguro Social (IMSS), en Hermosillo, Sonora. Se diseno un formato unico de reporte compuesto por los diferentes elementos que integran el sistema para la atencion del paciente diabetico en una Unidad de Medicina Familiar del IMSS. RESULTADOS: Se desarrollo e implemento un paquete de computacion (software) que permite la captura de los datos de dicho formato y la generacion de reportes, de tipo individual y grupal, sobre el cumplimiento de citas, antecedentes personales patologicos y no patologicos, evolucion de signos y sintomas, examenes de laboratorio y el manejo terapeutico. CONCLUSIONES: La sistematizacion de datos en forma electronica favorece la obtencion de informacion confiable y permanente para la vigilancia de los procesos en la atencion integral del paciente diabetico.