Eduardo Lazcano Ponce

Metabolic syndrome in Mexican adults: results from the National Health and Nutrition Survey 2006

OBJECTIVE To examine the prevalence of metabolic syndrome (MS) and its associated risk factors in Mexican adults aged 20 years or older, using data derived from the National Health and Nutrition Survey 2006 (ENSANUT 2006). MATERIAL AND METHODS The ENSANUT 2006 was conducted between October 2005 and May 2006. Questionnaires were administered to 45 446 adult subjects aged 20 years or older who were residents from urban and rural areas. Anthropometric and blood pressure measurements were obtained from all subjects and fasting blood specimens were provided by 30% of participants. We randomly selected a sub-sample of 6 613 from which laboratory measurements were carried out for glucose, insulin, triglycerides, total cholesterol and HDL-cholesterol. For this analysis, we included only results from eight or more hours of fasting samples (n=6 021). We used individual weighted factors in the statistical analysis and considered the surveys complex sampling design to obtain variances and confidence intervals. All analyses were done using SPSS 15.0. RESULTS In accordance with definitions by the National Cholesterol Education Program Adult Treatment Panel III (ATP III), the American Heart Association/National Heart, Lung and Blood Institute (AHA/NHLBI), and the International Diabetes Federation (IDF), the prevalence of MS in Mexican adults aged 20 years or older was 36.8, 41.6 and 49.8%, respectively. Women were more affected than men due to the higher prevalence of central obesity among females. Prevalence of MS increased with age and was higher among populations living in metropolitan areas, in the west-central region, and those with lower education. DISCUSSION Regardless of the MS definition, a large proportion of Mexican adults has the condition, so preventive measures are needed to decrease the prevalence of the MS components in this population. MS can predict type 2 diabetes and cardiovascular disease, two of the main causes of death in the adult population in Mexico. The intentional search of MS components allows stratifying the population according to risk levels. Treatment for each component should be implemented properly to prevent or delay onset of type 2 diabetes and cardiovascular disease.

Rapid Response of a Grassland Ecosystem to an Experimental Manipulation of a Keystone Rodent and Domestic Livestock

Megaherbivores and small burrowing mammals commonly coexist and play important functional roles in grassland ecosystems worldwide. The interactive effects of these two functional groups of herbivores in shaping the structure and function of grassland ecosystems are poorly understood. In North Americas central grasslands, domestic cattle (Bos taurus) have supplanted bison (Bison bison), and now coexist with prairie dogs (Cynomys spp.), a keystone burrowing rodent. Understanding the ecological relationships between cattle and prairie dogs and their independent and interactive effects is essential to understanding the ecology and important conservation issues affecting North American grassland ecosystems. To address these needs, we established a long-term manipulative experiment that separates the independent and interactive effects of prairie dogs and cattle using a 2 x 2 factorial design. Our study is located in the Janos-Casas Grandes region of northwestern Chihuahua, Mexico, which supports one of the largest remaining complexes of black-tailed prairie dogs (C. ludovicianus). Two years of posttreatment data show nearly twofold increases in prairie dog abundance on plots grazed by cattle compared to plots without cattle. This positive effect of cattle on prairie dogs resulted in synergistic impacts when they occurred together. Vegetation height was significantly lower on the plots where both species co-occurred compared to where either or both species was absent. The treatments also significantly affected abundance and composition of other grassland animal species, including grasshoppers and banner-tailed kangaroo rats (Dipodomys spectabilis). Our results demonstrate that two different functional groups of herbivorous mammals, burrowing mammals and domestic cattle, have distinctive and synergistic impacts in shaping the structure and function of grassland ecosystems.

Determinants of salivary cotinine levels among current smokers in Mexico

The present study describes salivary cotinine levels and their relationship to cigarettes smoked per day in Mexican smokers. Using a sampling strategy based on the number of cigarettes per day, we recruited 1,222 smokers from Mexico City and the state of Morelos in Mexico during 1999. Smoking behaviors and other factors known to affect nicotine intake and cotinine level were identified in an interview using a standardized questionnaire. Salivary cotinine was measured by capillary gas chromatography with nitrogen-phosphorus detection. We used generalized additive models to describe the relationship between salivary cotinine levels and variables of interest. The mean age of the population was 39.7 years (SD=15.6 years), with a mean cotinine level of 194.7 ng/ml (SD=134.8; range=10.1-767). Participants smoked a mean of 15.5 cigarettes per day (SD=11.3). Salivary cotinine and cigarettes smoked per day were positively related, although the association was not linear, flattening above 20 cigarettes per day. After adjusting for cigarettes per day, we found that significant predictors of cotinine levels included age, body mass index, cigarette producer, and smoking behavior variables. These results may have implications for dosing with nicotine medications to aid smoking cessation in Mexican smokers and suggest that whether the cigarette is labeled light or regular has no relationship to nicotine dose from smoking cigarettes.

HPV knowledge in Mexican college students: Implications for intervention programmes

In order to promote new human papillomavirus (HPV) prevention and detection methods effectively in Mexico, it is important to understand how much the population knows about the virus. This study aimed to determine the demographic and behavioural factors associated with HPV awareness and knowledge in a population of Mexican college students. With a response rate of 77%, data were collected from 1109 college students aged 17-25 years old at the Autonomous University of the State of Morelos in 2006. Students completed a questionnaire that assessed demographic and behavioural characteristics along with questions about HPV. A small percentage (16.9%) of the college students had never heard about HPV. Characteristics associated with not having heard about HPV included being male, not having running water, not having health insurance and not having sexual experience. Students had a median score of 5 out of 10 on an HPV knowledge index based on 10 yes/no questions about HPV developed for this study. Students had higher HPV knowledge scores if they studied health science, or science and engineering, were a fourth year student, had running water at home, had health insurance, or were a female who had had a previous Pap smear. Although most of these Mexican college students had heard of HPV, they had limited knowledge about the virus and prevention strategies. Further research in Mexican college students is needed to explain the variations in HPV knowledge to create appropriate health education programmes.

Proposal to institutionalize criteria and quality standards for cervical cancer screening within a health care system

The uterine cervix is the most common cancer site for females. Approximately 52,000 new cases occur annually in Latin America, thus the need to improve efficiency and effectiveness of Cervical Cancer Screening Programs (CCSP) is mandatory to decrease the unnecessary suffering women must bear. This paper is addressing essential issues to revamp the CCSP as proposed by the Mexican official norm. A general framework for institutionalizing CCSP is outlined. Furthermore, strategies to strengthen CCSP performance through managerial strategies and quality assurance activities are described. The focus is on the following activities: 1) improving coverage; 2) implementing smear-taking quality control; 3) improving quality in interpretation of Pap test; 4) guaranteeing treatment for women for whom abnormalities are detected; 5) improving follow-up; 6) development of quality control measures and 7) development of monitoring and epidemiological surveillance information systems. Changes within the screening on cervical cancer may be advocated as new technologies present themselves and shortcomings in the existing program appear. It is crucial that these changes should be measured through careful evaluation in order to tally up potential benefits.

Análisis costo beneficio del programa de detección oportuna del cáncer cervicouterino

Objetivo. Determinar el costo beneficio de la reorganizacion del Programa de Deteccion Oportuna del Cancer Cervicouterino (PDOC) mediante intervenciones de garantia de calidad. Material y metodos. Se siguieron tres etapas: a) identificacion y cuantificacion de costos; b) identificacion y cuantificacion de beneficios, y c) evaluacion economica del costo beneficio. Resultados. El costo unitario de operacion por citologia -obtencion, fijacion, el traslado al centro de lectura, su tincion e interpretacion y la notificacion de resultados- se estimo en USD

Effects of Pleistocene environmental changes on the distribution and community structure of the mammalian fauna of Mexico

11.6. En conjunto, las intervenciones en calidad al PDOC elevarian el costo de cada citologia en 32.7%. Sin embargo, la nueva organizacion generaria una razon beneficio/costo de 2 y un beneficio neto de 88 millones de dolares para los proximos cinco anos. Conclusiones. La operacion del programa propuesto resulta socialmente deseable, siempre y cuando las modificaciones se lleven a cabo, particularmente la capacitacion, la notificacion personalizada de los casos positivos, el incremento de cobertura, la introduccion de mecanismos de control de calidad, el monitoreo continuo y el tratamiento en mujeres con anormalidades detectadas.