Specimen self-collection and HPV DNA screening in a pilot study of 100,242 women.

Since cervical cancer remains common in Mexico despite an established cytology screening program, the Ministry of Health recently introduced pilot front-line HPV testing into the Mexican cervical cancer screening program (CCSP). Here, we present the key field performance metrics of this population-based study. High-risk HPV DNA (hrHPV) testing was conducted on self-collected vaginal specimens from 100,242 women aged 25-75 years residing in Morelos State. All hrHPV positive women and a random sample of 3.2% (n = 2,864) of hrHPV negative participants were referred for colposcopic examination. The main disease endpoint of interest was cervical intraepithelial neoplasia grade 2 or higher (CIN2+). We calculated relative risk, positive predictive value and negative predictive value adjusted for screening test verification bias. The overall prevalence of hrHPV was 10.8% (95% CI 10.6-11.0). Women positive for hrHPV had a relative risk of 15.7 for histologically detectable CIN2+. The adjusted positive predictive value of the hrHPV test was 2.4% (95% CI 2.1-2.7); whereas the adjusted negative predictive value was 99.8% (95% CI 99.8-99.9). These findings suggest that large-scale vaginal hrHPV testing in a middle-income country can identify women at greater risk of advanced cervical abnormalities in a programmatically meaningful way but care is warranted to ensure that disease not detectable at colposcopy is kept to a minimum. PASS shows areas that need improvement and sets the stage for wider use of hrHPV screening of self-collected vaginal specimens in Mexico.

A pilot study of HPV DNA and cytology testing in 50,159 women in the routine Mexican Social Security Program.

INTRODUCTION: We present a large feasibility evaluation of high-risk HPV (HR-HPV) DNA testing and cervical cytology as a primary screening strategy for cervical cancer precursor lesions in Mexican women, as part of a routine cancer control program (CCP). METHODS: A community-based study was carried out in 50,159 women aged 20-70 years who visited the CCP in 12 federal entities located in Northern, Central, and Southern Mexico, including a total of 48 primary health care units of the Instituto Mexicano del Seguro Social (IMSS). Cervical specimens for cytology and HR-HPV tests were collected at baseline. Women with cytological abnormalities (ASCUS or greater) were referred to colposcopy for further evaluation and treatment if necessary. A subset of HR-HPV-positive women without cervical lesions, in Morelos state, were tested again for HR-HPV DNA within a year, and repeat-positive women were referred to colposcopy. RESULTS: HR-HPV prevalence among all women was 8.6% (95% CI: 8.3-8.9). Prevalence by age group was 12.2% (95% CI: 11.0-13.3) before 30 years of age and decreased to 7.4% (95% CI: 6.7-8.0) between 46 and 50 years of age. A second minor prevalence peak (8.1%; 95% CI: 7.2-9.0) was observed in women more than 55 years of age. Overall prevalence of cytological abnormalities was relatively low (2.2%; 95% CI: 2.0-2.3) with the highest frequency of abnormal cytology (ASCUS or greater) in the 41-45 year age group (2.5%: 95% CI 2.1-2.7). No correlation between cervical abnormalities and HR-HPV prevalence, by region, was observed. A total of 370 (0.7%) women had an abnormal cytology as well as a positive HR-HPV result; 736 (1.5%) had an abnormal cytology and a negative HR-HPV test; 3,941 (7.9%) women had a positive HR-HPV test and a normal cytology; and 45,112 (89.9%) women were negative in both tests. The first two groups were immediately referred to colposcopy, 72.7% of the women from the cytology-positive and HR-HPV-positive group and 58.0% from the cytology-positive and HR-HPV-negative group successfully completing evaluation. Among the 269 cytology-positive and HR-HPV-positive women, 53 (19.7%) CIN2/3+ cases were detected, whereas among the 427 cytology-positive and HR-HPV-negative participants, only 13 (3.0%) CIN2/3+ cases were documented. In Morelos state, a sample of 287 women with a negative cytology smear and a positive HR-HPV test at baseline were re-screened after ~12 months, by means of cytology and HR-HPV testing. Among these women, 106 (36.9%) were again HR-HPV positive and were referred to colposcopy. Of whom, 76 (71.7%) were successfully evaluated; among these women, 9 CIN2/3+ (11.8%) were documented. Sensitivity of cervical cytology for detecting histologically confirmed CIN2/3+ cases was only 40.0% (95% CI 38.5-41.4) compared to 93.3% (95% CI 92.5-94.0) for HPV DNA testing considering the additional cases detected among women with persistent HPV infection. The specificity of cytology was 97.0 vs. 89.2% for the HPV DNA test. DISCUSSION: Population-based programs using HR-HPV testing can improve cervical cancer prevention and control in Mexican and other populations where cytological screening is inadequate for detecting precursors of cervical cancer.

Prevalence, concordance and determinants of human papillomavirus infection among heterosexual partners in a rural region in central Mexico.

BACKGROUND: Although human papillomavirus (HPV) infection in heterosexual couples has been sparsely studied, it is relevant to understand disease burden and transmission mechanisms. The present study determined the prevalence and concordance of type-specific HPV infection as well as the determinants of infection in heterosexual couples in a rural area of Mexico. METHODS: A cross-sectional study was conducted in 504 clinically healthy heterosexual couples from four municipalities in the State of Mexico, Mexico. HPV testing was performed using biotinylated L1 consensus primers and reverse line blot in cervical samples from women and in genital samples from men. Thirty-seven HPV types were detected, including hi223gh-risk oncogenic types and low-risk types. Multivariate logistic regression models were utilized to evaluate factors associated with HPV. RESULTS: The prevalence of HPV infection was 20.5% in external male genitals and 13.7% in cervical samples. In 504 sexual couples participating in the study, concordance of HPV status was 79%; 34 partners (6.7%) were concurrently infected, and 21 out of 34 partners where both were HPV positive (61.8%) showed concordance for one or more HPV types. The principal risk factor associated with HPV DNA detection in men as well as women was the presence of HPV DNA in the respective regular sexual partner (OR = 5.15, 95%CI 3.01-8.82). In men, having a history of 10 or more sexual partners over their lifetime (OR 2.5, 95%CI 1.3 - 4.8) and having had sexual relations with prostitutes (OR 1.7, 95%CI 1.01 - 2.8) increased the likelihood of detecting HPV DNA. CONCLUSIONS: In heterosexual couples in rural regions in Mexico, the prevalence of HPV infection and type-specific concordance is high. High-risk sexual behaviors are strong determinants of HPV infection in men.

[Obesity, physical activity and inactivity among adolescents in Morelos, Mexico: a longitudinal study]. / Obesidad, actividad e inactividad física en adolescentes de Morelos, Mexico: un estudio longitudinal.

The prevalence of obesity in childhood and adolescence has increased in Mexico. This increase can be explained partly by a decrease in physical activity. The objective of this study was to assess the association between the prevalence of obesity and overweight with physical activity and inactivity among Mexican adolescents. We analyzed data from a longitudinal study with baseline and follow-up measures in 446 adolescents 12 to 17 years old, attending public schools in Cuernavaca, Morelos, Mexico. We collected information on weight, physical activity and demographic characteristics. Obesity and overweight were determined using as indicador the body mass index, and the cutoff points proposed by the International Obesity Task Force. The baseline prevalence of obesity or overweight was 37.22% (42.99% for males and 30.95% for females), and in the final measure 34.30% (38.46% for males and 32.28% for females). The median time of TV viewing was 3.90 h/d, with 0.73 h/d dedicated to vigorous physical activity and 0.58 h/d to moderate physical activity. Using logistic regression, after adjustment for obesity in the baseline measure, sex and clustering by school, we found no significant associations between the prevalence of obesity or overweight with time dedicated to TV viewing, vigorous or moderate physical activity. However, when conducting the analysis with an interaction term by sex, we found significantly lower risk of obesity or overweight associated with an increase in vigorous physical activity among males only (beta = 0.22, 95% CI (0.05, 0.89). Results suggest that vigorous physical activity may reduce the risk of obesity or overweight among male adolescents.

HPV in female partners increases risk of incident HPV infection acquisition in heterosexual men in rural central Mexico.

BACKGROUND: Knowledge about the incidence, clearance, and factors associated with human papilloma virus (HPV) infection in men is lacking, and much of what is available focuses on high-risk groups. METHODS: A prospective cohort study was carried out with 504 heterosexual males from Mexico State, Mexico. Participants were monitored for 4 years at intervals of approximately 4 months, with a median total duration of follow-up of 19.8 months. The presence of cervical HPV in female sexual partners was evaluated as a risk factor. HPV DNA testing was conducted using the polymerase chain reaction technique. Risk factors associated with the incidence and clearance of HPV infection were evaluated through survival analysis. RESULTS: The cumulative incidence of infection with any HPV type at 12 months was 15% [95% confidence interval (CI), 0.12-0.20]. About 72% of men with incident HPV cleared the infection by 12 months. The presence of cervical HPV in a man's female sex partner was the main determinant for males acquiring HPV infection of any type [adjusted HR (AHR), 2.1; 95% CI, 1.1-3.8] and oncogenic HPV infection (AHR, 4.1; 95% CI, 2.1-8.0), while having a history of anal sexual relations with women was statistically associated with acquiring nononcogenic HPV (AHR, 1.8; 95% CI, 1.1-2.9). CONCLUSIONS AND IMPACT: The incidence of genital HPV infection in this population is relatively low, with relatively quick acquisition and clearance rates. Cervical HPV infection in men's female sexual partners was the main risk factor for genital HPV infection in men.

Obesidad, actividad e inactividad física en adolescentes de Morelos, México: un estudio longitudinal / Obesity, physical activity and inactivity among adolescents in Morelos, Mexico: a longitudinal study

La prevalencia de obesidad durante la niñez y adolescencia se ha incrementado en México, pudiendo explicarse por un decremento en la actividad física. Nuestro objetivo fue determinar la asociación entre la prevalencia de obesidad o sobrepeso con niveles de actividad e inactividad física en adolescentes mexicanos. Se utilizó información de 446 adolescentes de entre 12 y 17 años, que acudían a escuelas públicas secundarias en Cuernavaca, Morelos, México. Se empleó un diseño longitudinal con 2 mediciones, basal y final. Se captó información antropométrica, actividad e inactividad física, edad y sexo. Se calculó la prevalencia de obesidad o sobrepeso de acuerdo al criterio propuesto por el International Obesity Task Force, y se estimaron razones de momios o posibilidades mediante regresión logística. La prevalencia basal de obesidad o sobrepeso fue de 37.21% (42.99% para hombres y 30.95% para mujeres) y la final de 35.50% (38.46% para hombres y 32.28% para mujeres). La media final de tiempo total viendo TV fue de 3.90 h/d, de actividad vigorosa 0.73 h/d y de moderada 0.58 h/d. Ajustando el efecto de obesidad o sobrepeso inicial, sexo y escuela, no se encontraron asociaciones significativas entre tiempo viendo televisión o practicando actividad física con la prevalencia de obesidad o sobrepeso. Al incluir un término de interacción por sexo en nuestros modelos se encontró un efecto protector de la actividad vigorosa en los adolescentes varones (b=0.22, IC 95% (0.05, 0.89)). Los resultados sugieren que la actividad física vigorosa disminuye el riesgo de obesidad o sobrepeso en adolescentes varones.

The prevalence of obesity in childhood and adolescence has increased in Mexico. This increase can be explained partly by a decrease in physical activity. The objective of this study was to assess the association between the prevalence of obesity and overweight with physical activity and inactivity among Mexican adolescents. We analyzed data from a longitudinal study with baseline and follow-up measures in 446 adolescents 12 to 17 years old, attending public schools in Cuernavaca, Morelos, Mexico. We collected information on weight, physical activity and demographic characteristics. Obesity and overweight were determined using as indicador the body mass index, and the cutoff points proposed by the International Obesity Task Force. The baseline prevalence of obesity or overweight was 37.22% (42.99% for males and 30.95% for females), and in the final measure 34.30% (38.46 % for males and 32.28% for females). The median time of TV viewing was 3.90 h/d, with 0.73 h/d dedicated to vigorous physical activity and 0.58 h/d to moderate physical activity. Using logistic regression, after adjustment for obesity in the baseline measure, sex and clustering by school, we found no significant associations between the prevalence of obesity or overweight with time dedicated to TV viewing, vigorous or moderate physical activity. However, when conducting the analysis with an interaction term by sex, we found significantly lower risk of obesity or overweight associated with an increase in vigorous physical activity among males only (b=0.22, 95% CI (0.05, 0.89). Results suggest that vigorous physical activity may reduce the risk of obesity or overweight among male adolescents.

Análisis de productividad, calidad y costos en laboratorios del primer nivel: la biometría hemática / Analysis of productivity, quality and cost of first grade laboratories: complete blood count

Objetiva conhecer o grau de eficiência com que funcionam os laboratórios clínicos de primeiro nível através de uma avaliaçäo que integre: produtividade, qualidade e custos. De 52 laboratórios clínicos localizados na Cidade do México, selecionaram-se 10 laboratórios; utilizou-se o modelo de estrutura, processo e resultado de Donabedian, e a biometria hemática como rastreador. Os principais problemas encontrados foram: má distribuiçäo de recursos humanos qualificados; material de vidro em más condiçöes; técnica analítica inadequada; e recursos humanos com baixa produtividade. Esses probelmas representaram aumento de 200 por cento nos custos unitários em relaçäo ao custo ideal. Apenas 50 por cento dos laboratórios analisados tiveram resultados confiáveis. Somente 20 por cento dos laboratórios trabalharam com eficiência. Para solucionar os problemas encontrados será preciso usar estratégias integrais que comprometam os diferentes setores, mas de soluçäo difícil. Recomenda-se analisar o custo-benefício de criar um laboratório central e deixar os demais laboratórios com a funçäo exclusiva de selecionar amostras

Analisis de la participacion en encuestas de cinco paises : relevancia para la investigacion en salud publica / Analysis of participation in surveys in five countries : the importance for public health research

Se presenta una comparación de las tasas de participación y de las razones de la falta de respuesta en encuestas realizadas en cinco países de América Latina y el Caribe con el objetivo de medir la prevalencia de comportamientos de riesgo que determinan la transmisión del virus de la inmunodeficiencia humana. Dichas encuestas se basaron en muestras probabilísticas de la población de ambos sexos comprendida entre 15 y 49 años de edad, excepto en México, donde se estudió solo a los hombres. Se estimaron tres componentes de la participación: las proporciones de viviendas entrevistadas, de viviendas entrevistadas con personas elegibles y de personas elegibles que cumplimentaron la entrevista. Además, se calculó un índice global que combinaba los tres componentes. La tasa global de respuesta osciló entre 35,6 por ciento en México y 81,4 por ciento en Chile, y el componente de esta tasa con mayor variabilidad fue la participación de personas elegibles, que varió entre 50 por ciento en México y 95 por ciento en Cuba. Estos valores fueron más bajos de lo esperado, sobre todo en los hombres, y servirán de orientación para futuras encuestas, ya que se deberán considerar tasas de rechazo mayores de las previstas en el protocolo. Los resultados permiten inferir la validez de las estimaciones de la prevalencia de los diversos comportamientos de riesgo observados y establecen una referencia para calcular el tamaño muestral de futuras encuestas y mejorar la metodología de la investigación

Analisis de la participacion en encuestas de cinco paises: relevancia para la investigacion en salud publica / Analysis of participation in surveys in five countries: the importance for public health research

Se presenta una comparación de las tasas de participación y de las razones de la falta de respuesta en encuestas realizadas en cinco países de América Latina y el Caribe con el objetivo de medir la prevalencia de comportamientos de riesgo que determinan la transmisión del virus de la inmunodeficiencia humana. Dichas encuestas se basaron en muestras probabilísticas de la población de ambos sexos comprendida entre 15 y 49 años de edad, excepto en México, donde se estudió solo a los hombres. Se estimaron tres componentes de la participación: las proporciones de viviendas entrevistadas, de viviendas entrevistadas con personas elegibles y de personas elegibles que cumplimentaron la entrevista. Además, se calculó un índice global que combinaba los tres componentes. La tasa global de respuesta osciló entre 35,6 por ciento en México y 81,4 por ciento en Chile, y el componente de esta tasa con mayor variabilidad fue la participación de personas elegibles, que varió entre 50 por ciento en México y 95 por ciento en Cuba. Estos valores fueron más bajos de lo esperado, sobre todo en los hombres, y servirán de orientación para futuras encuestas, ya que se deberán considerar tasas de rechazo mayores de las previstas en el protocolo. Los resultados permiten inferir la validez de las estimaciones de la prevalencia de los diversos comportamientos de riesgo observados y establecen una referencia para calcular el tamaño muestral de futuras encuestas y mejorar la metodología de la investigación

This study compares participation rates and reasons for nonresponse in surveys conducted in five countries of Latin America and the Caribbean. The objective of the surveys was to measure the prevalence of risk behaviors affecting the transmission of human immunodeficiency virus. The surveys were based on probability samples of the population of both sexes between 15 and 49 years old, except in Mexico, where only men were included. Proportions of three components of participation were estimated: residences interviewed, interviewed residences with eligible persons, and eligible persons who completed the interview. In addition, an overall index that combined the three components was calculated. The overall response rate ranged from 35.6% in Mexico to 81.4% in Chile. The component with the greatest variability was the participation of eligible persons, which ranged from 50% in Mexico to 95% in Cuba. These values were lower than what had been expected, especially among men, and will serve to guide future surveys, since rejection rates higher than the ones expected in the protocol should be considered. The results make it possible to infer the validity of the prevalence estimates for the various observed risk behaviors. The results also establish a benchmark to calculate the sample size in future surveys and to improve research methodology

Factores asociados con el sexo desprotegido en trabajadoras del sexo de la ciudad de México / The cofactors of non-used of condoms in comercial sex in Mexico city.

Introducción; Una fracción de las aproximadamente 15,000 mujeres trabajadoras del sexo (MTS) en la ciudad de México no utilizan condones en encuentros sexuales comerciales. Urge conocer los cofactores de la falta de uso de condón con clientes en este grupo. Objetivo: Evaluar cofactores de la falta de uso del condón en un grupo de MTS de la ciudad de México. Métodos: Se entrevistaron 2727 MTS en su primera visita a una clínica pública de detección del virus de inmunodeficiencia humana(VIH) en la ciudad de México. Se definió la variable dependiente "sexo desprotegido" como la falta de la utilización o el uso infrecuente del condón con clientes (vs. uso del condón siempre o casi siempre). Se evaluaron los cofactores de acuerdo a las razones de momios crudas y ajustadas por medio de un modelo de regresión logística. Se calcularon los intervalos de confianza al 95 por ciento. Resultados: 17.7 por ciento de las MTS informaron que no utilizaban condones con sus clientes o los usaban sólo parte del tiempo. Los cofactores significativos de acuerdo con las razones de momios crudos fueron: edad de 26 años en adelante; tres o más dependientes económicos; escolaridad máxima de primaria; historia de gonorrea (factor protector); trabajo en la calle; falta de uso de un método anticonceptivo seguro; rechazo del uso del condón por parte de los clientes; clientes de nivel socioeconómico bajo; y uso irregular de los servicios de control de ETS. Conclusiones: Un poco menos de 20 por ciento de las MTS reportaron sexo desprotegido con clientes. Se requieren más acciones para la prevención de VIH otras ETS por parte de las MTS de la ciudad de México. Se deberían dirigir los esfuerzos especialmente hacia las mujeres que laboran en la calle