Obesity and metabolic risks in children.

BACKGROUND: We undertook this study to establish the prevalence of overweight, obesity, abdominal obesity, high blood pressure, and high glucose and triglyceride levels in school-age children from Mexico City, as well as to determine how overweight and obesity are related to the other risk factors. METHODS: The study was a cross-sectional survey comprised of 1819 children (6-13 years of age) attending six elementary schools. Gender, age, weight, height, waist circumference, blood pressure, and levels of triglycerides and glucose were registered. Percentiles were calculated according to American standards for BMI, height, waist circumference, and blood pressure. RESULTS: Compared to American references, mean percentiles for waist circumference and BMI were >50, and mean height percentiles were <50. Prevalence of overweight was 22.3 and 23.6% for boys and girls, respectively; obesity, 28 and 21.2%; abdominal obesity, 22.1 and 11.7%; high triglyceride levels, 11.3 and 15.4%; high blood pressure, 4.8 and 5.8%, respectively. Overweight, obesity, and abdominal obesity are associated with higher blood pressure and triglyceride levels (odds ratio>1.0, p<0.05). Percentiles for BMI, waist circumference, systolic blood pressure, and diastolic blood pressure also had significant correlations (r>0.2, p<0.001). CONCLUSIONS: This population of Mexican school-age children was shorter and heavier than their American standards. The prevalence of metabolic risks was similar to those reported in American adolescents in NHANES surveys.

[Morbidity and mortality by ischemic heart disease and stroke in Mexico. 2005]. / Morbilidad y mortalidad de la enfermedad isquémica del corazón y cerebrovascular en México, 2005.

Cardiovascular diseases are the main cause of death and disability in México. 25% of deaths under 60 years of age are related to chronic degenerative diseases. These disorders are more common in developing countries and are caused by an excessive intake of fatty acids, sodium, alcohol, tobacco consumption and decrease in physical activity. The prevalence of risk factors is increasing not only in adult population but also in youth and children. Data from the Department of Epidemiology from the Mexican Ministry of Health in the period between 1998 and 2000 showed that the death caused by coronary artery disease was more frequent in men (55%) than women (45%) and acute coronary syndrome was responsible for deaths in 83.5% of men and 76.8% in women. Primary Prevention Programs are necessary to decrease the impact of cardiovascular diseases.

Characteristics of patients with type 2 diabetes in México: Results from a large population-based nationwide survey.

OBJECTIVE: To describe the clinical characteristics of the diabetic population that formed part of a population-based survey conducted in México. RESEARCH DESIGN AND METHODS: In 2000, information was obtained from 42,886 subjects aged > or =20 years using a multistage sampling procedure. Standardized questionnaires were used. Anthropometric measurements, blood pressure, and capillary glucose concentrations were taken. RESULTS: Type 2 diabetes was found in 3,597 subjects (age-adjusted prevalence 8.18%), of which 2,878 (80%) had previously been diagnosed. The average age of the diabetic participants was 55.2 +/- 13.5 years; 13% were <40 years of age. Nine percent had been diagnosed for >10 years. The average BMI was 29.2 +/- 5.7 kg/m(2); three-quarters of the cases had BMI >25 kg/m(2). The average waist circumference was 102 +/- 13.4 cm, and increased waist circumference was more common among women. Arterial hypertension was found in half of the cases and, of those on treatment, only one-third had a blood pressure <140/90 mmHg. Smoking was reported in 34% of the diabetic group, a higher rate than in the nondiabetic subjects. There was at least one modifiable coronary risk factor in 67.6% of the cases. Very few followed an exercise or dietary regimen and a small percentage used insulin. CONCLUSIONS: Diabetes affects a large proportion of Mexican adults (8.18%). This figure may be underestimated. The majority of the subjects had modifiable risk factors for the chronic complications of diabetes. Only a few achieved adequate blood pressure control and other treatment goals.

[National Re-survey of Arterial Hypertension (RENAHTA). Mexican consolidation of the cardiovascular risk factors. national follow-up cohort]. / Re-encuesta Nacional de Hipertensión Arterial (RENAHTA): consolidación Mexicana de los factores de riesgo cardiovascular. Cohorte nacional de seguimiento.

OBJECTIVE: Based on a National Re-survey on Hypertension (HTA) and other cardiovascular risk factors performed in Mexico during 2003 and 2004 in the adult population with HTA, as identified in the 2000 National Survey of Health, this study was planed to determine: 1) morbidity and mortality rates; 2) the incidence and interrelation with other risk factors, such as overweight, obesity, dyslipidemia, nephropathy and diabetes; 3) the main risk factors associated to HTA involved in its complications, need for hospitalization and number of days; and, 4) the degree of therapeutical adhesion and the type of antihypertensive drugs used. METHODS: The survey was of type III using the step by step method described by WHO. Sampling was weighed a priori taking into account a national prevalence average of HTA of 30.05% and its corresponding rate for each federal state. Permissible maximum error in the estimation = 0.28. Effect of design = 4.5; and, Rate of awaited answer (0.70). RESULTS: From the initial 14,567 interviewed patients, 1,165 (8%) subjects were considered non-hypertensive or false positives at the 2000 survey. From the 13,402 remaining patients, 335 died during the first 2 years of pursuit, which implies an annual mortality of approximately 1.15% in the hypertensive population. Thus, 13,067 survivors were subjected to the final analysis. The mean age at the re-survey was 45.6 +/- 12.6; 40.5% were men (n = 5,295). There was a statistically significant difference in height, but not in weight between both genders. The control HTA was raised 14.6% in the year 2000 and 19.2% in 2004. The prevalence of diabetes was duplicated from 16% to 30% (< .001). Fifty four percent of the whole population required hospitalization at least once during the period of study. The rates of overweight, obesity, and dyslipidemia rose significantly (p < 0.05) independently from age, federal state, and gender. CONCLUSION: RENAHTA shows the impact of hypertension on the morbidity and mortality during the 3.1 +/- 1.5 years of follow-up in Mexico. It alerts us on the need to reinforce the strategies of attention and prevention of this crucial risk factor and of screening the dynamic nonlinear interaction between the main cardiovascular risk factors in Mexico. New hypotheses are proposed for the metabolic syndrome.

[Hypercholesterolemia and hypertension in Mexico: urban conjunctive consolidation with obesity, diabetes and smoking]. / Hipercolesterolemia e hipertensión arterial en México. consolidación urbana actual con obesidad, diabetes y tabaquismo.

AIMS: To know the prevalence and the interaction among the principal cardiovascular risk factors such as hypercholesterolemia (HCL), hypertension (HTA), overweight, carbohydrates metabolism disturbances, and smoking, an urban survey was performed in the six Mexican Republic states, where the national population is more concentrated. METHODS: This survey was transversally designed using the WHO type-III model in 120,005 adults from 6 highly populated urban centers (Mexico City, Guadalajara, León, Puebla, Monterrey andTijuana) were included. A blood sample from each person was obtained to quantify fasting glucose and cholesterol. Blood pressure, height and weight were measured using daily validated systems. Data were analyzed by a multicategorical conjunctive consolidation model and by multiple regression models. RESULTS: HCL global prevalence showed to be 43.3% for a population with an average age of 44.1 years. Female gender showed a slightly but statistically significant greater prevalence of HCL than male gender (44% vs 42.2%). From whole women population 33.2% declared to be in menopause, and 59.7% of them had HCL. In addition, HCL was directly related to body mass index (BMI). Thus, in those subjects with BMI < 25 showed a HCL prevalence 34.1%; while those with BMI was between 25 and 29.9, the HCL prevalence was 45.9%, and in those subjects with BMI > or = 30 Kg/m2, ranked a HCL prevalence of 47.3%. The prevalence of hypertension was 30.2% and 52.5% of them had HCL prevalence. Type-2 diabetes mellitus prevalence (DM-2) was 10.7%, 55.2% of them had HCL. In the group aged between 20 to 34 years old, the obesity was the principal determinant for higher HCL prevalence. The HCL prevalence showed to be quite similar in population with and without smoking. In conclusion, HCL prevalence shows 4 progressively increasing gradients associated with age, HTA, DM-2 and BMI.

[Arterial hypertension in Mexico: results of the National Health Survey 2000]. / Hipertensión arterial en México: Resultados de la Encuesta Nacional de Salud (ENSA) 2000.

AIMS: Hypertension remains as a major cause of cardiovascular morbidity in México. The Health National Survey 2000 of México was performed to analyze the current status of the prevalence of some risk factors such as diabetes, hypertension (HTA), obesity, smoking, and proteinuria. METHODS: A National Survey was carried out in México where 45,300 individuals between 20 to 69-y.o. were screened. The estimated sample size was calculated considering the total number of persons into the mentioned age; a minimal prevalence of 6% of the included risk factors, at a significance level of 0.05; a maximum relative error of 0.145, and a rate of response of at least 70%. Diagnosis of HTA was accepted in: previous medical diagnosis with prescription of antihypertensive drugs, or high blood pressure (> or = 140/90 mmHg) detected during the interview. Data were adjusted for the national distribution of age-groups and gender (established in 2000, INEGI). RESULTS: 38,377 (98.8%) individuals were correctly screened for blood pressure. The prevalence of hypertension in México was 30.05% (34.2% in men and 26.3% in women). The prevalence was directly related with age and gender. The percentage of mexicans with HTA after 50-y.o. is > 50%. The prevalence was greater in women after 50-y.o. Among persons with hypertension, treatment was detected in 46% and approximately 20% of them were controlled (< 140/90 mmHg). The percentage of mexicans with HTA who were unaware that they have high blood pressure was 61%. The total percentage of HTA controlled was 14.6%. The North states had the greater prevalence (approximately 34%) of HTA while South states had the lower prevalence (27%). The odds ratio (age/sex-adjusted) for HTA were: for diabetes 1.54(CI95%, 1.44-1.63); for obesity 2.3 (CI 95%, 2.22-2.43); for smoking 1.26 (CI 95%, 1.21-1.32). For proteinuria subjects, 40% had HTA. CONCLUSIONS: Around 15 millions of mexicans between 20 to 69-y.o. had hypertension, 60% of them are unaware. The prevalence of hypertension in México (30.05%) has increased. Among persons with hypertension -15% are controlled. The North of México has the higher prevalence of hypertension. Diabetes, smoking, and obesity increase the risk of hypertension. The 2000 National Survey of Health shows the epidemiological trend in several important chronic diseases in México and declare an urgent need of new strategies for detection, control and treatment of hypertension.

[Prevalence and interrelations of noncommunicable chronic diseases and cardiovascular risk factors in Mexico. Final outcomes from the National Health Survey 2000]. / Prevalencia e interrelación de enfermedades crónicas no transmisibles y factores de riesgo cardiovascular en México: Resultados finales de la Encuesta Nacional de Salud (ENSA) 2000.

PURPOSE: To determine the prevalence and interrelation of noncommunicable chronic diseases (NCCD), obesity, smoking, and proteinuria in the adult population (between 20 and 69 years of age) of Mexico, and their stratification according to age, gender, and geographical area. METHOD: During the year 2000, a probabilistic national survey was performed in 45,300 persons. The sample size was calculated to approach NCCD with a minimal estimated prevalence of 6%. The survey corresponds to type III of the step-by-step method described by WHO. Data were weighted for the distribution of the population and gender, according to the national survey of population and housing (National Institute of Statistics and Geography, INEGI). RESULTS: A total of 38,377 (98.8%) of individuals were included in the analysis; 69.4% were women. Average age for men was 39.4 +/- 12.9 and for women 38.6 +/- 13.0. National average prevalence for hypertension was 30.05%, for diabetes of 10.7%, for obesity of 24.4%, for abnormal capillary glucose of 12.7%, and for proteinuria of 9.2%. Prevalence for hypertension and diabetes were directly related with age, body mass index, and waist perimeter. The pyramidal distribution of the Mexican population determined that the greatest proportion of prevalence of NCCD was given by those under 54 years of age with a statistical significance (> 75%). CONCLUSION: ENSA 2000 demonstrates the marked increase in NCCD prevalence in the Mexican population and alerts on the urgent need of national strategies to restrain this important public health problem. Strategies must be oriented towards an integrated approach of the NCCD, since their clinical and physiopathological interrelation is clearly demonstrated through ENSA 2000.

Individual risk factors for Plasmodium vivax infection in the residual malaria transmission focus of Oaxaca, Mexico.

OBJECTIVE: To identify individual risk factors for malaria infection of inhabitants in the residual transmission focus on the Pacific coast of Oaxaca, Mexico. MATERIALS AND METHODS: A population-based, matched case-control study was conducted from January 2002 to July 2003 comparing the frequency of exposure to individual risk factors in subjects presenting clinical malaria and uninfected controls. A malaria case was defined as an individual living in the study area presenting malaria symptoms and a Plasmodium vivax-positive thick blood smear; controls were individuals negative to P. vivax parasites and antibodies of the same gender and with +/- five years as the case. A standardized questionnaire was used to record information about the individual risk factors associated with malaria episodes in cases and two controls for each case. RESULTS: In a multiple conditional logistic regression model analysis of data from 119 cases and 238 controls, 18 out of 99 variables were significantly associated (p< 0.05) with increased risk of malaria, including: being born in another locality (RM 3.16, 95% IC 1.16-6.13); speaking only an autochthonous language (RM= 2.48, 95% IC 1.19-3.77); having poor knowledge about malaria (RM= 2.26 95% IC 1.10-4.66 P< 0.02); the amount of vegetation around the house (RM= 20.43, 95% IC 5.98-70.87, P< 0.000; RM= 3.78, 95% IC 1.21-11.80, for 60-100% and 30-59%, respectively); living in houses constructed with perishable materials (RM= 2.85, 95% IC 1.62-5.01); living on the periphery of the town (RM= 6.23, 95% IC 3.50-11.0); sleeping on a dirt floor (RM= 2.98, 95% IC 1.78-5.01) or with two or more people in the same bed (RM= 1.85, 95% CI 1.09-3.14); not using bed nets (RM= 2.39, 95% IC 1.18-4.83, P< 0.003) or using bed nets with holes (RM= 13.93, 95 IC 2.48-78.01); traveling outside of the village (RM= 9.16, 95% IC 1.98-42.2); and previous malaria cases in the house (RM= 5.84, 95% IC 3.33-10.22). CONCLUSIONS: Risk of malaria infection was associated with socio-cultural and environmental factors exposing individuals to mosquito bites. A higher risk of malaria infection occurred outside the locality and by intradomiciliar transmission probably as a result of relapsing asymptomatic relatives.

[Influenza pandemic: Mexico's response]. / Pandemia de influenza: la respuesta de México.

In 1992, a new type of influenza virus appeared in Southeast Asia. This new strain has caused to date, more than 120 cases and over 60 deaths in Cambodia,Vietnam, Indonesia and Thailand. This situation is seen by the experts as the possible genesis of a new influenza pandemic with the corresponding negative effects on the health of the population, international commerce and world economy. In order to face the coming challenge, the World Health Organization (WHO) has asked member countries to develop national preparedness and response plans for an influenza pandemic. Within the framework of the National Committee for Health Security, Mexico has developed a National Preparedness and Response Plan for an Influenza Pandemic with the aim of protecting the health of the population with timely and effective measures. The Plan is based on a risk scale and five lines of action: Coordination, Epidemiological Surveillance, Medical Care, Risk Communication and Strategic Stockpile. It is currently impossible to predict when the next pandemic will start or what will be its impact. Nevertheless, it is fundamental that national and regional health authorities establish measures for protecting the health of the population in case this emergency occurs.

Determinant factors for malaria transmission on the coast of Oaxaca State, the main residual transmission focus in Mexico.

OBJECTIVE: The purpose of this study was to investigate the influence of demographic, socioeconomic and ecological factors in malaria transmission in the most important residual transmission focus in Mexico, located in the state of Oaxaca. MATERIAL AND METHODS: The extension of the focus was determined by a spatial and time analysis of the distribution of malaria cases in the state between 1998 and 1999 using a Geographical Information System. A malaria transmission intensity index (MTII) was constructed based on the total number of cases during the study period and the duration and frequency of transmission outbreaks within the villages. The relationship between local determinants and malaria transmission intensity was investigated using multinomial and ordered logistic models. RESULTS: The distribution of villages according to their MTII was: 325 high, 341 medium, 142 low and 717 with no transmission. Localities of high MTII were associated with areas having a tropical climate with summer rains and low water evaporation. Most high MTII villages were located in elevations between 200 and 500 m above sea level, in the area around Pochutla City. The amount of temporary streams in the neighborhood of localities had a highly significant positive association with the MTII. Distance to roads was only significant in the high malaria MTII stratum. CONCLUSIONS: The main factors determining malaria transmission in the focus are related to good conditions for the breeding of mosquito vectors. The existence of short-range population movements around Pochutla, the main economically active city in the area, indicates the necessity to implement a system of epidemiological surveillance to halt the dispersion of new outbreaks.

[Changes in the prevalence of dental caries in schoolchildren in three regions of Mexico: surveys from 1987-1988 and 1997-1998]. / Cambios en la prevalencia de la caries dental en escolares de tres regiones de México: encuestas de 1987-1988 y de 1997-1998.

OBJECTIVE: To compare the prevalence and severity of dental caries found in epidemiological surveillance studies conducted in three areas of Mexico in two different periods, 1987-1988 and 1997-1998. METHODS: The 1987-1988 survey was done with representative samples of schoolchildren 6 to 10 years old in two states, Nuevo León and Tabasco, as well as in the country's Federal District (which includes Mexico City). The Federal District's 1987-1988 sample also included schoolchildren who were 12 years old. The total number of students examined in the 1987-1988 period was 7 590. The 1997-1998 survey included schoolchildren who were 6-10 years old and 12 years old, in all three of the areas. The total number of students included in the 1997-1998 survey was 8 164. To compare the prevalence and severity of dental caries in the two periods, the average value for the index of decayed, missing, and filled teeth (DMFT) was used with all of the age groups. RESULTS: The values of the DMFT indices were significantly lower in the 1997-1998 period for all of the age groups studied (P < 0.05 for all the age groups). In the 1997-1998 period both Tabasco and Nuevo León achieved the goal recommended by the World Health Organization of an average of no more than three decayed, missing, and filled teeth among the 12-year-olds, with DMFT indices of 2.67 and 1.72, respectively. However, in the Federal District in that 1997-1998 period the DMFT index exceeded the recommended level, with a value of 3.11. CONCLUSIONS: The reduction seen in the DMFT indices could be due to several factors, including the consumption of fluoridated salt, the use of dentifrices and fluoride rinses, and broader access to dental services.

Antigenic diversity and distribution of rabies virus in Mexico.

Rabies remains a public health problem in the Americas because of the great diversity of wild reservoirs that maintain the virus in nature. Here we report the antigenic characterization of 254 rabies viruses isolated from 148 nonreservoir and 106 reservoir hosts collected in 27 states of Mexico. Nine out of 11 antigenic variants previously reported in the United States were detected in Mexico by using the limited panel of monoclonal antibodies donated by the Centers for Disease Control and Prevention. Some rabies virus variants were isolated from their natural reservoirs, which were also taxonomically identified. Terrestrial reservoirs included stray dogs with V1, Urocyon cineroargenteus (gray foxes) with V7, and two subspecies of Spilogale putorius (spotted skunks) with different viral variants (V8 and V10). Aerial hosts included Tadarida brasiliensis mexicana and Desmodus rotundus, which harbored V9 and V4 and harbored V11, respectively. All variants, with the exception of V9, were isolated from nonreservoir hosts, while V3, V4, and V5 were not isolated from their natural reservoirs but only from livestock. Rabies virus antigenic typing allowed us to determine rabies reservoirs and their distribution in Mexico, data which will probably improve prevention and control of the illness in humans and in the reservoir hosts.

Anthropometric cutoff points for predicting chronic diseases in the Mexican National Health Survey 2000.

OBJECTIVE: To determine optimum anthropometric cutoffs for predicting the likelihood ratios of type 2 diabetes mellitus (DM) and hypertension (HT) in Mexicans. RESEARCH METHODS AND PROCEDURES: Data from a randomly selected, nationally representative health survey (2000) with 11,730 men [37.4 (+/- 12.9) years] and 26,647 women [37.3(+/- 12.9) years] were assessed for values of body mass index (BMI) and waist circumference (WC) for predicting DM or HT by receiver operating characteristic curve analyses. Likelihood ratios for DM and HT were calculated, and BMIs or WCs for public-health screening were developed. Subanalyses included regional data. RESULTS: Likelihood ratios of DM and HT increased from BMI values of 22 to 24 kg/m(2) in both sexes and with WC values of 75 to 80 cm in men and 70 to 80 cm in women. The best BMI cutoffs for predicting DM were 26.3 to 27.4 kg/m(2) in men and 27.7 to 28.9 kg/m(2) in women, with similar values for HT, i.e., 26.2 to 27.0 kg/m(2) and 27.7 to 28.5 kg/m(2), for men and women, respectively; WC cutoffs for DM were 93 to 98 cm in men and 94 to 99 cm in women, and cutoffs for HT were 92 to 96 cm and 93 to 96 cm for men and women, respectively. The WC cutoffs had higher sensitivity and specificity than those of BMI. DISCUSSION: The risk for DM and HT starts at lower levels of BMI and WC than those suggested by WHO. WC is a better discriminator than BMI measures for use in public health.

The high prevalence of overweight and obesity in Mexican children.

OBJECTIVE: To establish the prevalence of overweight and obesity in Mexican children 10 to 17 years of age according to the percentiles from both the Centers of Disease Control and Prevention (CDC) and the International Obesity Task Force (IOTF). RESEARCH METHODS AND PROCEDURES: Heights and weights were measured in children from nationally representative, randomly chosen households in the Mexican National Health Survey 2000. The study population consisted of 7862 boys and 8947 girls, 10 to 17 years of age. Measurements used were the percentage of children in the corresponding BMI categories for overweight and obesity specified by the CDC and the IOTF BMI percentiles. RESULTS: The children were short, with mean Z scores for height by age varying from - 0.62 +/- 1.26 to -1.12 +/- 1.06 in boys and from -0.45 +/- 1.25 to -1.19 +/- 1.12 in girls. CDC-based overweight prevalences varied by age from 10.8% to 16.1% in boys and 14.3% to 19.1% in girls, with obesity prevalences from 9.2% to 14.7% in boys and 6.8% to 10.6% in girls; these prevalences did not relate to stunting. IOTF-based excess weight prevalences were similar, with higher overweight rates (boys, 15.4% to 18.8%; girls, 18.4% to 22.3%) but lower obesity rates (boys, 6.1% to 9%; girls, 5.9% to 8.2%). DISCUSSION: Mexican children have one-half the overweight/obesity prevalences of U.S. Mexican-American children; however, there are higher rates in Northern Mexico, which is closer to the U.S. These escalating rates of excess weight demand new prevention, as well as management, policies.

Morbilidad y mortalidad de la enfermedad isquémica del corazón y cerebrovascular en México, 2005 / Morbidity and mortality by ischemic heart disease and stroke in Mexico. 2005

Cardiovascular diseases are the main cause of death and disability in México. 25% of deaths under 60 years of age are related to chronic degenerative diseases. These disorders are more common in developing countries and are caused by an excessive intake of fatty acids, sodium, alcohol, tobacco consumption and decrease in physical activity. The prevalence of risk factors is increasing not only in adult population but also in youth and children. Data from the Department of Epidemiology from the Mexican Ministry of Health in the period between 1998 and 2000 showed that the death caused by coronary artery disease was more frequent in men (55%) than women (45%) and acute coronary syndrome was responsible for deaths in 83.5% of men and 76.8% in women. Primary Prevention Programs are necessary to decrease the impact of cardiovascular diseases.

Individual risk factors for Plasmodium vivax infection in the residual malaria transmission focus of Oaxaca, Mexico

OBJECTIVE: To identify individual risk factors for malaria infection of inhabitants in the residual transmission focus on the Pacific coast of Oaxaca, Mexico. MATERIALS AND METHODS: A population-based, matched case-control study was conducted from January 2002 to July 2003 comparing the frequency of exposure to individual risk factors in subjects presenting clinical malaria and uninfected controls. A malaria case was defined as an individual living in the study area presenting malaria symptoms and a Plasmodium vivax-positive thick blood smear; controls were individuals negative to P. vivax parasites and antibodies of the same gender and with ± five years as the case. A standardized questionnaire was used to record information about the individual risk factors associated with malaria episodes in cases and two controls for each case. RESULTS: In a multiple conditional logistic regression model analysis of data from 119 cases and 238 controls, 18 out of 99 variables were significantly associated (p< 0.05) with increased risk of malaria, including: being born in another locality (RM 3.16, 95 percent IC 1.16-6.13); speaking only an autochthonous language (RM= 2.48, 95 percent IC 1.19-3.77); having poor knowledge about malaria (RM= 2.26 95 percent IC 1.10-4.66 P< 0.02); the amount of vegetation around the house (RM= 20.43, 95 percent IC 5.98-70.87, P< 0.000; RM= 3.78, 95 percent IC 1.21-11.80, for 60-100 percent and 30-59 percent, respectively); living in houses constructed with perishable materials (RM= 2.85, 95 percent IC 1.62-5.01); living on the periphery of the town (RM= 6.23, 95 percent IC 3.50-11.0); sleeping on a dirt floor (RM= 2.98, 95 percent IC 1.78-5.01) or with two or more people in the same bed (RM= 1.85, 95 percent CI 1.09-3.14); not using bed nets (RM= 2.39, 95 percent IC 1.18-4.83, P< 0.003) or using bed nets with holes (RM= 13.93, 95 IC 2.48-78.01); traveling outside of the village (RM= 9.16, 95 percent IC 1.98-42.2); y..

OBJETIVO: Identificar los factores de riesgo individuales determinantes para contraer paludismo en habitantes del foco residual de transmisión de paludismo localizado en la costa del Pacífico de Oaxaca. MATERIAL Y MÉTODOS: Se realizó un estudio pareado de casos y controles, con base poblacional de enero de 2002 a julio de 2003, comparando la frecuencia de exposición a diversos factores de riesgo individuales en sujetos que presentaron un cuadro clínico de paludismo y controles no infectados. Un caso de paludismo fue definido como un individuo que vive en el área de estudio que presentó síntomas de paludismo y diagnosticado positivo a P. vivax en examen de gota gruesa de sangre, los controles fueron individuos negativos a parásitos y anticuerpos anti-P. vivax del mismo sexo y ± cinco años la edad del caso. Se usó un cuestionario estandarizado para registrar información de factores de riesgo individuales asociados a episodios de paludismo en casos y dos controles por caso. RESULTADOS: El análisis en un modelo de regresión logística condicional múltiple, 18 de 99 variables fueron significativamente asociadas (p< 0.05) con el incremento en el riesgo de paludismo, incluyendo: nacer fuera de la localidad (RM 3.16, 95 por ciento IC 1.16-6.13); hablar sólo un idioma autóctono (RM= 2.48, 95 por ciento IC 1.19-3.77); pobre conocimiento de cómo se transmite y trata el paludismo (RM= 2.26 95 por ciento IC 1.10-4.66 P< 0.02); cobertura de vegetación alrededor de la casa (RM= 20.43, 95 por ciento IC 5.98-70.87, P< 0.000; RM= 3.78, 95 por ciento IC 1.21-11.80, para 60-100 por ciento y 30-59 por ciento, respectivamente); casas construidas con materiales perecederos (RM= 2.85, 95 por ciento IC 1.62-5.01); localización de la casa en la periferia de la localidad (RM= 6.23, 95 por ciento IC 3.50-11.0); dormir en el suelo (RM= 2.98, 95 por ciento IC 1.78-5.01); dormir con dos o más personas en la misma cama (RM= 1.85, 95 por ciento CI 1.09-3.14); not...

Pandemia de influenza: la respuesta de México / Influenza pandemic: Mexico's response

En 1992 apareció en el sureste asiático un nuevo tipo de virus de la influenza, el cual ha ocasionado hasta la fecha m s de 120 casos y un poco más de 60 defunciones en humanos en Camboya, Vietnam, Indonesia y Tailandia. Esta situación es considerada por los expertos como la probable génesis de una nueva pandemia de influenza, lo que podría traer graves consecuencias para la salud de la población, así como para la economía y el comercio mundial. Por lo anterior, la Organización Mundial de la Salud (OMS) ha instado a los países miembros a desarrollar planes de preparación y respuesta para hacer frente a esta eventualidad. En el marco del Comit‚ Nacional para la Seguridad en Salud, México ha diseñado el Plan Nacional de Preparación y Respuesta ante una Pandemia de Influenza con objeto de proteger a la población mediante acciones efectivas y oportunas. El Plan utiliza una escala de riesgo y define cinco líneas de acción: Coordinación, Vigilancia Epidemiológica, Atención Médica, Difusión y Movilización Social, y Reserva Estratégica. Si bien es imposible predecir cuándo se presentar  la próxima pandemia y su impacto, es fundamental que las autoridades de salud nacionales, estatales y locales establezcan los mecanismos para poner en marcha los componentes del Plan en forma oportuna y garantizar con ello la salud de la población en caso de influenza pandémica.

Determinant factors for malaria transmission on the coast of Oaxaca State, the main residual transmission focus in Mexico / Factores determinantes de la transmisión de paludismo en la costa del estado de Oaxaca, el principal foco residual de transmisión en México

OBJECTIVE: The purpose of this study was to investigate the influence of demographic, socioeconomic and ecological factors in malaria transmission in the most important residual transmission focus in Mexico, located in the state of Oaxaca. MATERIAL AND METHODS: The extension of the focus was determined by a spatial and time analysis of the distribution of malaria cases in the state between 1998 and 1999 using a Geographical Information System. A malaria transmission intensity index (MTII) was constructed based on the total number of cases during the study period and the duration and frequency of transmission outbreaks within the villages. The relationship between local determinants and malaria transmission intensity was investigated using multinomial and ordered logistic models. RESULTS: The distribution of villages according to their MTII was: 325 high, 341 medium, 142 low and 717 with no transmission. Localities of high MTII were associated with areas having a tropical climate with summer rains and low water evaporation. Most high MTII villages were located in elevations between 200 and 500 m above sea level, in the area around Pochutla City. The amount of temporary streams in the neighborhood of localities had a highly significant positive association with the MTII. Distance to roads was only significant in the high malaria MTII stratum. CONCLUSIONS: The main factors determining malaria transmission in the focus are related to good conditions for the breeding of mosquito vectors. The existence of short-range population movements around Pochutla, the main economically active city in the area, indicates the necessity to implement a system of epidemiological surveillance to halt the dispersion of new outbreaks.

OBJETIVO: Investigar la participación de factores demográficos, socio-económicos y ecológicos en la transmisión de la malaria en el foco de transmisión residual más importante en México, localizado en el estado de Oaxaca. MATERIAL Y MÉTODOS: La extensión del foco se determinó por medio de un análisis espacio-temporal de la distribución de casos de malaria en el estado entre 1998 y 1999, usando un Sistema de Información Geográfico. Un índice de intensidad de transmisión de malaria (MTII, por sus siglas en inglés) se construyó basado en el número total de casos durante el periodo del estudio y la duración y frecuencia de brotes de transmisión dentro de las localidades. La relación de determinantes locales con el MTII se investigó por medio de modelos multinomiales logísticos. RESULTADOS: La distribución de localidades según su MTII fue de 325 alto, 341 medio, 142 bajo y 717 sin transmisión. Localidades con MTII alto estuvieron asociadas a las áreas de clima tropical con lluvias en verano y evaporación baja. La mayoría de las localidades con MTII alto se localizaron a elevaciones entre 200 y 500 msnm, en el área alrededor de la ciudad de Pochutla. La cantidad de arroyos temporales en la vecindad de localidades tuvo una asociación positiva significativa con el MTII. La cercanía a carreteras de localidades con MTII alto fue significativa. CONCLUSIONES: Los factores principales que determinan la transmisión de la malaria en el foco están relacionados con las condiciones favorables para la cría de mosquitos vectores. La participación de movimientos de población de rango cortos alrededor de Pochutla, la principal ciudad económicamente activa en el área, indica la necesidad de implementar un sistema de vigilancia epidemiológica para detener la dispersión de nuevos brotes.

Re-encuesta Nacional de Hipertensión Arterial (RENAHTA): Consolidación Mexicana de los Factores de Riesgo Cardiovascular. Cohorte Nacional de Seguimiento / National Re-survey of Arterial Hypertension (RENAHTA). Mexican consolidation of the cardiovascular risk factors. National Follow-up Cohort

Propósito: A través de una Re-encuesta Nacional sobre Hipertensión Arterial Sistémica (HTAS) y Factores de Riesgo Cardiovascular, en población adulta con HTAS identificada en encuestas nacionales de salud del año 2000; Determinar: 1) Las tasas de morbilidad y mortalidad. 2) La incidencia e interrelación en el tiempo con otros factores de riesgo, tales como Obesidad, Dislipidemia, Diabetes y Tabaquismo. 3) Los principales factores de riesgo asociados a HTAS que influencian la aparición de complicaciones, necesidad y numero de días de hospitalización. 4) El grado de adherencia y tipo de medicación usada por el paciente hipertenso. Métodos: La Re-encuesta Nacional de Hipertensión (RENAHTA) fue realizada en el periodo 2003-2004. La encuesta es tipo III del método paso a paso descrito por la OMS. La población estudiada correspondió en su mayoría (73%) a individuos detectados en encuestas nacionales previas. El muestreo fue ponderado a priori tomando en cuenta una prevalencia nacional promedio de HTAS de 30.05% y su correspondiente para cada estado de la República. Error máximo permisible en la estimación = 0.28, Efecto de diseño = 4.5; y, Tasa de respuesta esperada (0.70). Resultados: De 14 567 como muestra inicial, 1165 (8%) sujetos fueron considerados como no hipertensos o falsos positivos en el año 2000. De los 13,402 pacientes restantes se informaron 335 muertes ocurridas en los primeros 2 años de seguimiento (2000-2002), lo que implicó una mortalidad anual de ˜1.15% en la población hipertensa. Así, 13,067 sobrevivientes, fueron sujetos a análisis. La edad al momento de la re-encuesta fue 45.6 ± 12.6. El (40.5%) fueron hombres (n=5,295), hubo diferencia estadísticamente significativa en la talla, pero no en el peso entre ambos géneros. El control de la HTAS subió de 14.6% en el 2000 a 19.2% en el 2004. Se duplicó la cifra de diabéticos de 16% a 30% (p < .001). El 54% de la población estudiada requirió de hospitalización al menos ...

Objective: Based on a National Re-survey on Hypertension (HTA) and other cardiovascular risk factors performed in Mexico during 2003 and 2004 in the adult population with HTA, as identified in the 2000 National Survey of Health, this study was planed to determine: 1) morbidity and mortality rates; 2) the incidence and interrelation with other risk factors, such as overweight, obesity, dyslipidemia, nephropathy and diabetes; 3) the main risk factors associated to HTA involved in its complications, need for hospitalization and number of days; and, 4) the degree of therapeutical adhesion and the type of antihypertensive drugs used. Methods: The survey was of type III using the step by step method described by WHO. Sampling was weighed a priori taking into account a national prevalence average of HTA of 30.05% and its corresponding rate for each federal state. Permissible maximum error in the estimation = 0.28. Effect of design = 4.5; and, Rate of awaited answer (0.70). Results: From the initial 14,567 interviewed patients, 1,165 (8%) subjects were considered non-hypertensive or false positives at the 2000 survey. From the 13,402 remaining patients, 335 died during the first 2 years of pursuit, which implies an annual mortality of ˜1.15% in the hypertensive population. Thus, 13,067 survivors were subjected to the final analysis. The mean age at the re-survey was 45.6 ± 12.6; 40.5% were men (n = 5,295). There was a statistically significant difference in height, but not in weight between both genders. The control HTAwas raised 14.6% in the year 2000 and 19.2% in 2004. The prevalence of diabetes was duplicated from 16% to 30% (< .001). Fifty four percent of the whole population required hospitalization at least once during the period of study. The rates of overweight, obesity, and dyslipidemia rose significantly (p < 0.05) independently from age, federal state, and gender. Conclusion: RENAHTA shows the impact of hypertension on the morbidity and mortality during the 3.1 ± 1.5 years of follow-up in Mexico. It alerts us on the need to reinforce the strategies of attention and prevention of this crucial risk factor and of screening the dynamic nonlinear interaction between the main cardiovascular risk factors in Mexico. New hypotheses are proposed forthe metabolic syndrome.