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Eduardo Lazcano-Ponce

Publications and source records attributed to Eduardo Lazcano-Ponce.

At least 19 recordsLinked to original sources
PubMed2006

Variations in the age-specific curves of human papillomavirus prevalence in women worldwide.

An inverse relationship between age and human papillomavirus (HPV) prevalence has been reported in many developed countries, but information on this relationship is scarce in many other parts of the world. We carried out a cross-sectional study of sexually active women from the general population of 15 areas in 4 continents. Similar standardised protocols for women's enrolment, cervical specimen collection and PCR-based assays for HPV testing were used. HPV prevalence in different age groups was compared by study area. 18,498 women aged 15-74 years were included. Age-standardised HPV prevalence varied more than 10-fold between populations, as did the shape of age-specific curves. HPV prevalence peaked below age 25 or 35, and declined with age in Italy, the Netherlands, Spain, Argentina, Korea and in Lampang, Thailand and Ho Chi Minh, Vietnam. This was not the case in Songkla, Thailand nor Hanoi, Vietnam, where HPV prevalence was low in all age groups. In Chile, Colombia and Mexico, a second peak of HPV prevalence was detected among older women. In the poorest study areas in Asia (Shanxi, China and Dindigul, India), and in Nigeria, HPV prevalence was high across all age groups. The substantial differences observed in age-specific curves of HPV prevalence between populations may have a variety of explanations. These differences, however, underline that great caution should be used in inferring the natural history of HPV from age-specific prevalences.

Adolescent↗
PubMed2006

Prevalence and determinants of human papillomavirus infection in men attending vasectomy clinics in Mexico.

Large studies of genital human papillomavirus (HPV) infection in men are few and mainly include high-risk groups. We interviewed 779 men who requested a vasectomy in 27 public clinics in 14 states of Mexico. Exfoliated cells were obtained from the scrotum, the shaft of the penis, the top of the penis including the coronal sulcus, the glans and the opening of the meatus. HPV testing was performed using biotinylated L1 consensus primers and reverse line blot. Unconditional logistic regression was used to estimate odds ratios (ORs) of being HPV-positive and corresponding 95% confidence intervals (CIs). The prevalence of any type of HPV was 8.7%. HPV positivity was highest among men below age 25 (13.6%), and lowest among men aged 40 years or older (6.0%). The most commonly found HPV types were, in decreasing order, HPV59, 51, 6, 16 and 58. Lifetime number of sexual partners was associated with HPV positivity (OR for > or = 4 vs. 1 partner = 3.7, 95% CI: 2.0-6.8), mainly on account of the strong association with number of occasional and sex-worker partners. Condom use with both regular (OR = 0.4, 95% CI: 0.1-1.0) and sex-worker (OR = 0.1, 95% CI: 0.0-0.3) partners and circumcision (OR = 0.2, 95% CI: 0.1-0.4) were inversely associated with HPV positivity. HPV prevalence in Mexican men was similar to the prevalence found in Mexican women of the same age groups. The association between HPV positivity and lifetime number of sexual partners in the present low-risk male population is one of the strongest ever reported in studies in men. Condom use and circumcision were associated with a strong reduction in HPV prevalence.

Adult↗
PubMed2006

Chapter 24: Psychosocial aspects of vaccine acceptability.

In this chapter we identify psychosocial issues that have been raised with respect to human papillomavirus (HPV) vaccination and review the research literature on HPV vaccine acceptability. Many women and physicians have relatively poor knowledge about HPV, but despite this, most healthcare providers are willing to recommend HPV vaccination and parents are interested in having their children vaccinated. Concerns about post-vaccination sexual behavior change do not appear to be justified, but can certainly be addressed through anticipatory guidance. Most research studies have come out of the United States and other English-speaking industrialized countries. More psychosocial research regarding HPV vaccination is therefore needed from developing countries.

Developed Countries↗
PubMed2006

Overweight and obesity status among adolescents from Mexico and Egypt.

BACKGROUND: Obesity is on the rise among adults, adolescents and children worldwide, including populations living in developing countries. This study aimed to describe body mass index of adolescents from Mexico and Egypt and to evaluate non-nutritional correlates from two cohort studies. METHODS: Questionnaire data and weight and height measurements were collected in two large baseline studies in adolescents between 11 and 19 years old attending public school during the 1998-1999 school year in Mexico (n = 10,537) and the 1997 school year in Egypt (n = 1,502). The authors compared body mass index and correlates stratified by sex and country through multivariate linear regression. RESULTS: Overall prevalence of overweight and obesity was 19.8 and 7.9%, respectively, among the Mexican adolescents and 12.1 and 6.2%, respectively, among the Egyptian adolescents. Based on U.S. Centers for Disease Control and Prevention (CDC) definition growth charts, for Mexico 18% of boys and 21% of girls were overweight and 11% of boys and 9% of girls were obese. In the Egyptian sample, 7% of boys and 18% of girls were overweight and 6% of boys and 8% of girls were obese. The most consistent correlates of body mass index in the Mexican population were age, years of education, smoking, vitamin intake and participating in sports, whereas the factors correlated among Egyptian adolescents were age and rural residence. CONCLUSIONS: Obesity and overweight are becoming a problem among Mexican and Egyptian youth. Information about the risk factors associated with excessive weight gain during the adolescent period is a first step towards proposing prevention strategies.

Adolescent↗
PubMed2006

Costs of medical care for acute myocardial infarction attributable to tobacco consumption.

BACKGROUND: Tobacco consumption is the principal modifiable risk factor causally associated with acute myocardial infarction (AMI). AMI has been an increasing and important cause of death in Mexico since 1980. METHODS: To estimate the direct health care costs of AMI, we carried out a cost of illness (COI) analysis, using data derived from an expert panel consensus and from medical chart review. We used the smoking attributable fraction (SAF) estimates to derive costs of tobacco consumption. We also estimated the benefits of a "Smoke-free Workplace" tobacco control policy in terms of avoidable deaths and health care costs savings. RESULTS: We estimated an annual average costs of 6,420 US dollars and 9,216 US dollars for non-ST segment elevation AMI (NSTEMI) and ST segment elevation AMI (STEMI), respectively. The total annual health care costs estimated for incident AMI for the IMSS state-level division of Morelos reached 2.9 million US dollars, of which 1.6 million US dollars was directly attributed to tobacco consumption. CONCLUSIONS: Our results confirm the high costs associated with smoking and show the potential benefits resulting from a tobacco control policy. Our estimates are only applicable to social security in the state-level division of Morelos and more likely represent a lower boundary of the total costs of cardiovascular diseases attributed to tobacco, because we based the costs estimation on incident cases, and we did not take into consideration the costs derived from prevalent cases, indirect costs or other intangibles.

Acute Disease↗
PubMed2006

Folate, vitamin B(6), and vitamin B(12) intake and the risk of breast cancer among Mexican women.

BACKGROUND: High intake of folate, vitamin B(6), and vitamin B(12) have been hypothesized to lower the risk for breast cancer. We conducted a population-based case-control study to evaluate the risk for breast cancer among Mexican women with relatively low vitamin intakes. METHODS: We included 475 women (median age, 53 years; range, 23-87 years) diagnosed with incident breast cancer through six hospitals in Mexico City and interviewed them to obtain data on breast cancer risk factors and their usual diet using a food frequency questionnaire. We selected 1,391 (median age, 49 years; range, 18-82 years) controls from the Mexico City population using a national sampling frame. RESULTS: Compared with women in the lowest quartile, the odds ratio for breast cancer for women in the highest quartile of folate intake was 0.64 [95% confidence intervals (CI), 0.45-0.90; P, test for trend = 0.009] and 0.32 (95% CI, 0.22-0.49; P, test for trend < 0.0001) for vitamin B(12) intake. Among postmenopausal women, intakes of folate and vitamin B(12) were associated with a lower risk of breast cancer and those associations were stronger than among premenopausal women. The inverse association of folate and breast cancer was stronger among women who consumed a high level of vitamin B(12) as compared with women consuming diets low in vitamin B(12). No association was observed for vitamin B(6) intake. CONCLUSIONS: In this population, high intakes of folate and vitamin B(12) were independently associated with decreased breast cancer risk, particularly among postmenopausal women.

Adult↗
PubMed2006

Sexual behavior, condom use, and human papillomavirus: pooled analysis of the IARC human papillomavirus prevalence surveys.

Human papillomavirus (HPV) is a sexually transmitted infection but it is unclear whether differences in transmission efficacy exist between individual HPV types. Information on sexual behavior was collected from 11 areas in four continents among population-based, age-stratified random samples of women of ages > or = 15 years. HPV testing was done using PCR-based enzyme immunoassay. Unconditional logistic regression was used to estimate odds ratios (OR) of being HPV positive and corresponding 95% confidence intervals (95% CI). Variables were analyzed categorically. When more than two groups were compared, floating confidence intervals were estimated by treating ORs as floating absolute risks. A total of 11,337 women (mean age, 41.9 years) were available. We confirmed that lifetime number of sexual partners is associated with HPV positivity (OR for > or = 2 versus 1, 1.86; 95% CI, 1.63-2.11) but the association was not a linear one for HPV18, 31, and 33 (i.e., no clear increase for > or = 3 versus 2 sexual partners). Women who had multiple-type infection and high-risk HPV type infection reported a statistically nonsignificant higher number of sexual partners than women who had single-type and low-risk type infections, respectively. Early age at sexual debut was not significantly related to HPV positivity. Husband's extramarital sexual relationships were associated with an OR of 1.45 (95% CI, 1.24-1.70) for HPV positivity in their wives after adjustment for age and lifetime number of women's sexual partners. We did not observe a significant association with condom use. Our study showed an effect of both women's and their husbands' sexual behavior on HPV positivity. Furthermore, it suggests some differences in the pattern of the association between sexual behavior and different HPV types.

Adolescent↗
PubMed2006

Reproductive factors, oral contraceptive use, and human papillomavirus infection: pooled analysis of the IARC HPV prevalence surveys.

High parity, early age at first full-term pregnancy (FTP), and long-term oral contraceptive (OC) use increase cervical cancer risk, but it is unclear whether these variables are also associated with increased risk of acquisition and persistence of human papillomavirus (HPV) infection, the main cause of cervical cancer. Information on reproductive and menstrual characteristics and OC use were collected from 14 areas worldwide, among population-based, age-stratified random samples of women aged 15 years or older. HPV testing was done using PCR-based enzyme immunoassay. Unconditional logistic regression was used to estimate the odds ratios (OR) of being HPV-positive according to reproductive and menstrual factors and corresponding 95% confidence intervals (CI). When more than two groups were compared, floating CIs (FCI) were estimated. A total of 15,145 women (mean age, 40.9 years) were analyzed. Women with >or=5 FTPs (OR, 0.90; 95% FCI, 0.76-1.06) showed a similar risk of being HPV-positive compared with women with only one FTP (OR, 1.00; 95% FCI, 0.86-1.16). However, nulliparous women showed an OR of 1.40 (95% CI, 1.16-1.69) compared with parous women. Early age at first FTP was not significantly related to HPV positivity. HPV positivity was similar for women who reported >or=10 years of use of OCs (OR, 1.16; 95% FCI, 0.85-1.58) and never users of OCs (OR, 1.00; 95% FCI, 0.90-1.12). Our study suggests, therefore, that high parity, early age at first FTP, and long-term OC use are not associated with HPV prevalence, but rather these factors might be involved in the transition from HPV infection to neoplastic cervical lesions.

Adolescent↗
PubMed2006

[Dating violence and associations with depression and risk behaviors: female students in Morelos, Mexico].

OBJECTIVE: Determine the prevalence of dating violence and its association with depression and various risk behaviors in a sample of female students from the state of Morelos. MATERIAL AND METHODS: This is a baseline cohort study of a sample of 13 293 students from 12 to 24 years of age who attended public schools in the state of Morelos during the 1998-1999 school year. The participants were selected from a random sample of 260 junior high schools, 92 high schools and one university. For the purpose of this analysis, a total of 4 587 female students who had a previous dating relationship were selected. To control for possible confounding variables, multiple logistic regression analysis was used. RESULTS: The total prevalence of dating violence in females who attended public schools in Morelos was 28%. The following variables were associated with dating violence: depression (OR = 1.92; 95% CI 1.61-2.28); tobacco smoking (OR = 1.31; 95% CI 1.06-1.60); alcohol abuse (OR = 1.30, 95% CI 1.12-1.51); poor academic performance (low grades) (OR = 1.25; 95% CI 1.03-1.52); a history of sexual relations (OR = 1.52; 95% CI 1.26-1.82). CONCLUSIONS: The results of this study clearly indicate that women experience partner violence beginning with dating during adolescence. Health and education professionals need to establish intervention strategies to prevent or treat dating violence among female students. Such strategies should take into account the association between depression and violence, as well as other related risk behaviors.

Adolescent↗
PubMed2006

Effect of the peroxisome proliferators-activated receptor (PPAR) gamma 3 gene on BMI in 1,210 school students from Morelos, Mexico.

UNLABELLED: Little research has been undertaken on risk factors for obesity in young people in Latin America, including Mexico, despite the fact that obesity constitutes the number one public health problem in Mexico. Our objective was to investigate the effect of the Peroxisome proliferators-activated receptor (PPAR)_3 gene on BMI measured among adolescents collected from a cohort study originally designed for epidemiological studies. METHODS: Blood samples and anthropometric measurements were collected from 1,210 out of 13,294 public school students of both sexes, aged 11-24 years in Morelos, Mexico. In this study, we genotyped 7 selected SNPs of the PPAR_ transcript variant 3 (including Pro12Ala) in a group of unrelated 717 males and 493 females (age range 11-24), including 3 SNPs located in the 5' untranslated region. These 7 SNPs were selected by the tagging algorithm implemented in the program haploview to scan the whole gene. We tested each of the 7 SNPs individually for association with the body mass index (BMI), and two SNPs (rs2938392 and rs1175542) revealed significant associations with BMI (p-value=0.008 and 0.029, respectively). The SNP rs2938392 is roughly 41.5 Kb from rs1801282 (Pro12Ala in PPAR_2). Furthermore, we examined the association between haplotypes built from 7 SNPs and BMI using a score statistic implemented in the program haplo.stats. While the permutation based global p-value was 0.544, one individual haplotype with a frequency of 0.279 gave a p-value of 0.089 (permutation based). However, when the analyses were conducted in males only, the permutation based global p-value was 0.055 and one individual haplotype with a frequency of 0.28 gave a significant p-value of 0.013.

5' Untranslated Regions↗
PubMed2005

Glycemic load, glycemic index, and the risk of breast cancer among Mexican women.

OBJECTIVE: The amount and composition of dietary carbohydrates is a major determinant of postprandial blood glucose and insulin, and risk of breast cancer has been positively associated with plasma levels of insulin and insulin-like growth factor 1. We sought to evaluate dietary glycemic load (GL) and overall glycemic index (GI) in relation to breast cancer risk in Mexican women. METHODS: We examined dietary GL and overall GI and breast cancer risk among 475 women with histologically-confirmed breast cancer and a random sample of 1391 women from Mexico City households. Diet was assessed using a food frequency questionnaire adapted to the Mexican population. RESULTS: The multivariate adjusted or for all women comparing the highest quartile of dietary GL with the lowest quartile was 1.62 (95% CI 1.13-2.32; p-test for trend = 0.02) with a significant trend. In postmenopausal women, the multivariate adjusted or comparing the extreme quartiles was 2.18 (95% CI 1.34-3.55; p-test for trend=0.005). Overall GI was not significantly associated with risk of breast cancer. CONCLUSION: High intake of rapidly absorbed carbohydrate appears to play an important role in the risk of breast cancer in Mexican women.

Adult↗
PubMed2005

Consumption of higher numbers of cigarettes in Mexican youth: the importance of social permissiveness of smoking.

This study sought to assess the relationship between level of cigarette smoking and social factors indicating permissiveness of smoking among youth. This was a school-based cross-sectional questionnaire study carried out in a random sample of students (n=13,293, 11-24 years) at public schools in Morelos, Mexico. Chi2 test and multiple logistic regression analysis were used to evaluate correlates of level of smoking (> or < or = 5 cigarettes/day). There is a rising trend in smoking among Mexican in-school youth, a tendency towards smoking initiation at increasingly younger ages and a decrease in the gender gap regarding smoking. When young people smoked at home, at school and outside, they were over fives times as likely to smoke >5 cigarettes/day. Prevention of smoking among Mexican adolescents should emphasize smoke-free schools, no smoking policies in the community and parental anti-tobacco education.

Adolescent↗
PubMed2005

Associations between individual and contextual factors and smoking in 13,293 Mexican students.

OBJECTIVE: Factors correlated with cigarette smoking in young people have yet to be documented in most developing countries. This study assesses the correlates of smoking in Mexican young people. METHODS: School-based, cross-sectional study in the central Mexican state of Morelos during the 1998-1999 school year of 13,293 public school students aged 11 to 24 years. Multinomial logistic regression models were constructed with smoking as the dependent variable. RESULTS: Regular smoking (one or more cigarettes daily) prevalence was 13.1% (95% confidence interval [CI]=12.2-13.9) in males, and 6.1% (95% CI=5.6-6.6) in females. Frequent alcohol intoxication was strongly associated with regular smoking (females, odds ratio [OR]=68.5, 95% CI=37.6-125.2; males, OR=34.5, 95% CI=22.6-52.7). Regular smoking was associated with illegal drug use and smoking by both parents in females, and with illegal drug use in males (males, OR=4.9, 95% CI=3.7-6.5). Also associated with tobacco smoking were high socioeconomic status, low academic achievement, illegal drug use by peers, marijuana use by parents, and depression in adolescents. CONCLUSIONS: This study documents a strong correlation between tobacco smoking and other health risk behaviors, especially alcohol and drug abuse. In young women especially, the risk of tobacco use increased with alcohol abuse and higher socioeconomic status. School-based interventions are needed that focus on preventing smoking and also take into account other unhealthy behaviors.

Adolescent↗
PubMed2005

Current wheezing, puberty, and obesity among mexican adolescent females and young women.

BACKGROUND: Studies suggest an association between obesity and asthma. This may be modified by the physiological changes of puberty. We aim to explore the relation between overweight and current asthma among Mexican adolescent females and young women and evaluate how puberty may modify this association. METHODS: Adolescent females (n=6944) and young women aged 11-24 years provided data. Current asthma was defined as wheezing in the last 12 months and obesity by body mass index (BMI). Puberty was defined by age at menarche. The association of obesity and current wheezing was evaluated by using logistic regression adjusting for confounders. The impact of puberty was studied by using stratified analysis by age at menarche. RESULTS: The prevalence of current wheezing was 16.2% (95% CI 15-17). Compared with girls of normal weight (BMI 15 to >or=85 percentile), obese girls (BMI>or=95 percentile) had an increased risk of current wheezing of 19% (OR=1.19; 95% CI 0.97-1.46). After stratifying by age at menarche, we observed that this increased risk was only present in girls with menarche at 11 years old or younger (1.31%; 95% CI 1.01-1.73). CONCLUSIONS: The association between obesity and asthma seems to be greater among girls with early puberty, suggesting the role of female hormones.

Adolescent↗
PubMed2005

Determinants of prevalence, acquisition, and persistence of human papillomavirus in healthy Mexican military men.

BACKGROUND: Human papillomavirus (HPV) infection is sexually transmitted, but the nature of the infection in males is poorly understood. We sought to identify determinants of HPV infection, acquisition, and persistence in 1,030 healthy military men in Mexico. METHODS: From July 2000 to July 2003, trained interviewers administered a questionnaire, conducted a genital examination, and collected samples. The presence of multiple HPV types in genital cells from the urethra, urethral meatus, scrotum, penile shaft, and coronal sulcus was evaluated. At baseline 1,030 participants and after 1-year follow-up 336 individuals were sampled using a highly sensitive DNA reverse blot strip assay. RESULTS: HPV prevalence was 44.6%; infection with high-risk types was observed in 34.8% participants and 51.1% were multiply infected. After 1-year follow-up, 165 men remained free of HPV, 68 cleared their infection, 45 acquired one, and 37 remained infected with the same HPV type. The period prevalence was 50.9%, the incidence rate was 17.9/1,000 men-months [95% confidence interval (95% CI), 13.0-23.9], clearance was 54%, and persistence was 29.4%. At baseline, the number of partners before age 20 years, a history of a sexually transmitted disease, and the presence of condilomas significantly increased the association with HPV infection. Having anal intercourse with males was associated with the risk of acquiring a HPV infection (odds ratio, 5.2; 95% CI, 1.2-23). The odds ratio for persistent infection was 0.10 (95% CI, 0-0.87) in men who reported being circumcised compared with those who did not. CONCLUSIONS: High-risk sexual behavior increases the risk of HPV infection in males, whereas circumcision may lower the risk of persistence.

Adult↗
PubMed2004

Levels and correlates of knowledge about cancer risk factors among 13,293 public school students in Morelos, Mexico.

BACKGROUND: Data on young people's knowledge about cancer prevention are not currently available for many populations, including Mexican young people, although cancer is the second most common cause of death among the Mexican population. METHODS: A questionnaire was applied to 13,293 public school students aged 11-24 years in Morelos, Mexico. A knowledge-based scale was constructed from survey answers about risk factors for cancer. Data were analyzed using multivariate logistic multinomial models. RESULTS: Knowledge levels were low: 78% of male and 74% of female students had only wrong answers to questions about risk factors for cancer. A significant dose-response gradient was observed between age and knowledge of cancer risk factors (P < 0.001), with a higher prevalence in young women at all ages (female students OR 4.6, 95% CI 3.81-5.66). Students 18 years old and older knew more than 13-year-olds (OR = 2.39; 95% CI 1.89-3.01). Sexually active students (OR 2.10; 95% CI 1.70-2.58), especially those who consistently used condoms (OR 2.84; 95% CI 1.00-8.07), knew more about cancer prevention. Tobacco smoking was the most frequently recognized cancer risk factor, and smokers also recognized this as an important cause of cancer (OR 1.37; 95% CI 1.44-2.52). CONCLUSIONS: Our results reveal a poor level of knowledge about cancer prevention among adolescents. These data are the first step in the development of an intervention based on empirical findings that will be susceptible to evaluation.

Adolescent↗
PubMed2004

Determinants of Helicobacter pylori seroprevalence in Mexican adolescents.

BACKGROUND: Helicobacter pylori infection is one of the most common human infections and is considered to play an etiologic role in several gastroduodenal diseases. In this study we determined the H. pylori seroprevalence among adolescents in Morelos, Mexico, and explored the association between seroprevalence and socioeconomic, dietary and lifestyle variables. MATERIALS AND METHODS: A cross-sectional study was conducted in 5861 Mexican subjects aged 11-21 years. H. pylori infection was determined by an enzyme-linked immunosorbent assay previously validated in Mexico. A self-administered questionnaire was used to collect information on sociodemographic factors, housing, living conditions and food consumption. Multivariate logistic regression methods were used to obtain odds ratios and 95% confidence intervals. RESULTS: The overall H. pylori seroprevalence was 47.6%; 40.6% in preadolescents (11-14 years), 48.6% in adolescents (15-17 years), and 59.8% in young adults (18-24 years). A positive association was found between age and H. pylori seroprevalence. Inverse associations were found for availability of drinking water, sewerage, and home appliances at the time of the subject's birth, a proxy variable of socioeconomic status. Intake of milk products and total fats was positively associated with infection. CONCLUSIONS: This large seroprevalence study showed that H. pylori infection is frequent among adolescents in Mexico. An early acquisition of infection is indirectly suggested. Some variables denoting low socioeconomic status were inversely associated with H. pylori seroprevalence. Associations with intake of milk products and total fats suggest new hypotheses in this field of research.

Adolescent↗