Dietary micronutrients and cervical dysplasia in southwestern American Indian women

Food consumption pattern in cervical carcinoma patients and controls

Background:

The uterine cervix is the second most common site of cancer among Indian women.Though the human papillomavirus has been demonstrated to be a causative agent for this cancer, a variety of other risk factors are in play, such as sexual and reproductive patterns, socioeconomic, hygienic practices, and diet. The accumulated evidence suggests that cervical cancer is preventable and is highly suitable for primary prevention. The dietary intake of antioxidants and vitamins like vitamin A, carotenoids, vitamin C, folacin and tocopherol is found to have protective effects against cancer of the cervix. Dietary data regarding cervical cancer are still scanty.

Objective:

The present study was therefore undertaken to study the dietary pattern among uterine cervical cancer patients and normal controls.

Materials and Methods:

A total of 60 consecutive patients and 60 controls were enrolled from a referral hospital during the year 2004. A schedule inclusive of the food frequency pattern and 24-h dietary recall along with the general information was administered to all the enrolled subjects to describe findings on the food consumption pattern along with other important factors.

Results:

The mean intake of energy, protein, vitamins, etc., between the cases and controls was not significantly different except for the vitamin C level. Serum vitamin E was found to have lower average in patients as compared to controls. The nutrient intake of cervical cancer patients and controls was grossly deficient in the socioeconomic group studied. With regard to the macronutrient intake, calorie and protein intakes showed a deficit of around 50% when compared to RDA.

Conclusion:

The food consumption profile was not significantly different between cervical cancer patients and normal controls.

Vitamin or antioxidant intake (or serum level) and risk of cervical neoplasm: a meta-analysis

BACKGROUND

Case-control studies have reported the preventive effect of vitamin or antioxidant intake on cervical neoplasms such as cervical intraepithelial neoplasia (CIN) and invasive cervical cancer. However, the findings are inconsistent.

OBJECTIVE

To investigate quantitative effects of vitamin or antioxidant intake on cervical neoplasm using meta-analysis.

SEARCH STRATEGY

We searched PubMed, EMBASE and the Cochrane Library in November 2008. All articles searched were independently reviewed and selected by two evaluators according to predetermined selection criteria.

SELECTION CRITERIA

We included case-control studies reporting an association between vitamin or antioxidant intake (or serum level) and cervical neoplasm risk and reporting the adjusted odds ratios (OR) and 95% confidence intervals (CI), whenever possible.

DATA COLLECTION AND ANALYSIS

After retrieval of data from selected articles, we performed a meta-analysis using both fixed-effects and random- effects models.

MAIN RESULTS

Of 274 articles meeting our initial criteria, we included 22 case-control studies involving a total of 10,073 participants. In meta-analyses by type of vitamin or antioxidant, a significant preventive effect on cervical neoplasm was found in intakes of vitamin B12 (OR 0.35, 95% CI 0.19-0.63; n=2), vitamin C (OR 0.67, 95% CI 0.55-0.82; n=8), vitamin E (OR 0.56, 95% CI 0.35-0.88; n=10), and beta-carotene (OR 0.68, 95% CI 0.55-0.84; n=9).

AUTHORS' CONCLUSIONS

The findings of this meta-analysis indicate that overall, there were preventive effects of vitamin or antioxidant intake on cervical neoplasms in case-control studies.

Risk factors for HPV infection among American Indian and white women in the Northern Plains

OBJECTIVE

American Indian (AI) women living in the Northern Plains have high incidence and mortality rates for cervical cancer. We assessed risk factors for human papillomavirus (HPV) infection among AI and White women.

METHODS

We tested cervical samples for HPV infection obtained from women ages 18-65 years attending 2 rural AI reservation clinics in South Dakota (n=235) and an urban clinic serving predominantly White women (n=246). Patients self-reported information on HPV risk factors. We used percentages and chi-square tests to compare risk factors, and logistic regression with HPV status as the outcome to quantify the association between HPV and risk factors.

RESULTS

AI women had more risk factors than White women, including younger age, less education, less vegetable consumption, more sexual partners, younger age at first sexual experience and first pregnancy, and more pregnancies (p values≤0.003). AI women more often endorsed recreational drug use, history of sexually transmitted diseases, and current smoking; White women reported more alcohol consumption (p values<0.001). In multivariate analysis, younger age and current smoking were associated with higher odds of HPV infection in AI women, whereas a higher number of sexual partners was associated with higher odds of HPV infection in White women.

CONCLUSIONS

AI women have a high burden of risk factors for HPV disease, and associations with HPV infection appear to differ by community. Knowledge of specific risk factors in AI populations may provide targets for public health officials to decrease HPV infection and disease.

Pilot phase IIA study for evaluation of the efficacy of folic acid in the treatment of laryngeal leucoplakia

BACKGROUND

It has been previously observed that patients with head and neck squamous cell carcinoma or with laryngeal leucoplakia present a significant reduction in plasma folate levels. The current Phase IIA pilot study assessed the effectiveness of folic acid as a chemopreventive agent in patients affected by glottic laryngeal leucoplakia.

METHODS

Forty-three untreated patients affected by glottic laryngeal leucoplakia were enrolled in the Ear, Nose, and Throat Department (Universita Cattolica del Saco Cuore, Rome, Italy). Glottic leucoplakia was initially diagnosed by indirect laryngoscopy and successively confirmed by diagnostic direct microlaryngoscopy with a biopsy for histologic assessment. Folic acid (Folina, Schwarz Pharma, Germany) was administered orally (5 mg every 8 hours) for 6 months. Patients were monitored every 30 days by videolaryngoscopy.

RESULTS

Twelve (28%) patients had no response, 19 (44%) had a partial response, and 12 (28%) had a complete response. The mean increase in serum folate levels (10.06 +/- 0.53) and the mean decrease in homocysteine serum (3.65349 +/- 0.85526) at the end of the study were highly significant (P = .0001).

CONCLUSIONS

The larynx is 1 of the sites of major interest and a good model for the development of chemopreventive agents, but so far the proposed agents have shown no clear efficacy on precancerous lesions or on the development of second malignancies.

Serum levels of folate, homocysteine, and vitamin B12 in head and neck squamous cell carcinoma and in laryngeal leukoplakia

BACKGROUND

The authors evaluated serum levels of folate, homocysteine, and vitamin B(12) in patients with head and neck squamous cell carcinoma (HNSCC) and in patients with laryngeal leukoplakia, a well known preneoplastic lesion.

METHODS

One hundred forty-four consecutive, untreated patients with HNSCC and 40 consecutive, untreated patients with laryngeal leukoplakia were enrolled in the Department of Otolaryngology at the authors' institution. Data from those patients were compared with data from one control group, which included 90 smokers, and from another control group, which included 120 nonsmokers. Serum levels of homocysteine, folate, and vitamin B(12) were measured by an automated immunoassay method based on fluorescence polarization immunoassay technology.

RESULTS

Comparing groups by Student-Newman-Keuls test, serum folate levels were significantly lower in patients with HNSCC and in patients with laryngeal leukoplakia compared with serum folate levels in both the smoker control group and the nonsmoker control group. Serum homocysteine levels in patients with HNSCC were significantly higher compared with homocysteine levels both in the smoker and nonsmoker control groups and in patients with laryngeal leukoplakia. There were no statistically significant differences between groups in serum vitamin B(12) levels.

CONCLUSIONS

A role for folate deficiency as a risk factor in head and neck carcinogenesis is plausible. A chemoprevention protocol with folate is both feasible and ethically correct and is in progress at the authors' institution. Homocysteine levels in patients with HNSCC probably are affected largely by the HNSCC phenotype. An accumulation of homocysteine may reveal a genetic defect, which, theoretically, may be a target for pharmacologic therapy, for example, with antifolic drugs.

Folate, vitamin B12, and homocysteine status. findings of no relation between human papillomavirus persistence and cervical dysplasia

OBJECTIVES

Human papillomavirus (HPV) infections are the cause of most, if not all, cervical cancers. Women consistently positive for oncogenic type HPV infections have a greater risk of developing cervical dysplasia compared with women transiently infected. HPV infection alone appears to be insufficient to produce disease, suggesting that other cofactors may be needed. Folate, vitamin B12, and homocysteine, through their role in DNA methylation, may be involved in cervical neoplasia.

METHODS

This study examined the associations between HPV persistence and circulating folate, vitamin B12, and homocysteine levels among 91 low-income Hispanic women. Further, the relation of these nutrients to cervical pathology was evaluated. HPV status was determined at two visits approximately 3 mo apart.

RESULTS

Adjusted mean circulating concentrations of folate, vitamin B12, and homocysteine were not statistically different between women with two positive HPV tests, one positive test, or two negative HPV tests. No association was observed between tertiles of folate, vitamin B12, or homocysteine and HPV persistence risk. Further, adjusted mean levels of these nutrients were not statistically different between cytologic grades.

CONCLUSIONS

Results from this small study did not support a role for folate, vitamin B12, or homocysteine in HPV persistence or cervical dysplasia.

Relationship of folate to colorectal and cervical cancer: review and recommendations for practitioners

Evidence suggests that folate may play a role in cancer prevention. A plausible mechanism for prevention lies in the integral role that folate plays in deoxyribonucleic acid (DNA) synthesis and methylation. DNA methylation most likely regulates gene expression. Abnormal methylation, specifically hypomethylation, has been associated with tumorigenesis. The availability of methyl groups needed for adequate DNA methylation may be negatively influenced by low folate status, alcohol intake, or genetic polymorphisms that affect folate metabolism. Observational studies evaluating the association between folate and risk for colorectal and cervical cancers or precancerous conditions have produced conflicting results, and clinical trial data are needed to confirm a cause-and-effect relationship. However, several studies show interesting associations between cancer risk and factors that influence methyl group availability. Although data relating folate to cancer risk remain equivocal, when coupled with the other potential health benefits associated with folate, evidence supports recommending that people consume folate-rich foods such as fruits and vegetables. People consuming alcohol on a daily basis may especially benefit from additional folate in their diets.

Serum micronutrients and cervical dysplasia in Southwestern American Indian women

We carried out a clinic-based case-control study to assess serum micronutrients as risk factors for cervical dysplasia among Southwestern American Indian women, a group with high rates of cervical preinvasive lesions. Cases were American Indian women with biopsy-proven cervical intraepithelial neoplasia (CIN I or CIN II/III). Controls were from the same Indian Health Service clinics with normal cervical epithelium. We interviewed women about histories of sexually transmitted diseases, sexual behavior, diet, hygienic practices, cigarette smoking, and reproductive factors. Laboratory assays included serum for retinol (vitamin A), ascorbic acid (vitamin C), alpha-tocopherol (vitamin E), and red blood cell folate levels, DNA for human papillomavirus (HPV) typing, and tests for other sexually transmitted diseases. The strongest risks for cervical dysplasia were associated with cervical HPV infection [odds ratio (OR) = 3.2, 95% confidence interval (CI) = 2.2-4.6 and OR = 7.9, 95% CI = 4.8-13.1 for CIN I and CIN II/III, respectively]. With adjustments made for HPV infection and other relevant confounders, subjects in the lowest serum retinol quartile were at increased risk of CIN I compared with women in the highest quartile (OR = 2.3, 95% CI = 1.3-4.1). The data suggest that low serum alpha-tocopherol was associated with CIN I/III, although the adjusted OR was not statistically significant (OR = 2.0, 95% CI = 0.9-4.8). Low serum ascorbic acid and red blood cell folate were not associated with cervical dysplasia.

Low serum and red blood cell folate are moderately, but nonsignificantly associated with increased risk of invasive cervical cancer in U.S. women

Previous observational epidemiologic studies of folate and cervical cancer, as well as folate supplementation trials for cervical dysplasia, have produced mixed results. We examined the relationship between serum and RBC folate and incident invasive cervical cancer in a large, multicenter, community-based case-control study. Detailed in-person interviews were conducted, and blood was drawn at least 6 mo after completion of cancer treatment from 51% of cases and 68% of controls who were interviewed. Blood folate was measured with both microbiologic and radiobinding assays. Included in the final analyses were 183 cases and 540 controls. Logistic regression was used to control for all accepted risk factors, including age, sexual behavior, smoking, oral contraceptive use, Papanicolaou smear history and human papillomavirus (HPV)-16 serology. For all four folate measures, the geometric mean in cases was lower than in controls (e.g., 11.6 vs. 13.0 nmol/L, P < 0.01 for the serum radiobinding assay). Folate measures using microbiologic and radiobinding assays were correlated (serum: r = 0.90; RBC: r = 0.77). For serum folate, multivariate-adjusted odds ratios (OR) in the lowest vs. highest quartile were 1.3 [95% confidence interval (CI) = 0.8--2.9] and 1.6 (0.9--2.9), using the microbiologic and radiobinding assays, respectively. For RBC folate, comparable OR were 1.2 (0.6--2.2) and 1.5 (0.8--2.7). Similar risks were obtained when restricting analyses to subjects with a history of HPV infection. Thus, low serum and RBC folate were each moderately, but nonsignificantly, associated with increased invasive cervical cancer risk. These findings support a role for one-carbon metabolism in the etiology of cervical cancer.

Dietary intake and blood levels of lycopene: association with cervical dysplasia among non-Hispanic, black women

We examined whether elevated levels of retinoids, carotenoids, folate, and vitamin E protected against cervical dysplasia among non-Hispanic, black women. We enrolled 32 women with incident cervical dysplasia, including cervical intraepithelial neoplasia (CIN) I, CIN II, and CIN III/carcinoma in situ, and 113 control women with normal cervical cytology in case-control study. Micronutrient levels were estimated from a food-frequency questionnaire (FFQ) and measured from blood samples. Information on risk factors for cervical neoplasia was elicited by interview. Hybrid capture was used to determine infection with human papillomavirus. After adjustment for potential confounders, analysis of micronutrient levels estimated from the FFQ suggested that women in the upper tertile of lycopene and vitamin A intake were one-third (odds ratio = 0.32, 95% confidence interval = 0.8-1.3) and one-fourth (odds ratio = 0.24, 95% confidence interval = 0.05-1.2) as likely, respectively, to have dysplasia as women in the lower tertile. Borderline protective trends (p < or = 0.10) were apparent. Elevated levels of serum lycopene also suggested some protection against dysplasia. Results were not significant at alpha = 0.05 because of the small number of case women enrolled. Overall, correlations between estimates from the FFQ and serum levels were poor. This study indicates that, among black women, lycopene and perhaps vitamin A may play a protective role in the early stages of cervical carcinogenesis.

Risk factors for pre-cancerous lesions of the cervix

Studies on risk factors for pre-cancerous lesions of the uterine cervix have shown strong association with sexual practice. Women with multiple sexual partners and intercourse at early age are at high risk. A role of male partners in further enhancing the risk has been identified. All these support the hypothesis relating to a sexually transmissible aetiological agent. An extensive review of the literature on the risk factors for pre-cancerous lesions of cervix has been carried out. The risk factors were grouped into genital, sexual, chemical, dietary and life factors. Human papilloma virus (HPV) is the major infectious aetiological agent associated with the development of pre-cancerous lesions of cervix. Other co-factors such as multiple sexual partners of the male as well as the female and early age of first intercourse are also involved at the critical aetiological step of progression from low-grade to high-grade lesions. The role of other infectious agents in terms of supportive or interactive effects is not clear. No independent effect for herpes simplex virus 2 on risk is observed. Other risk factors include cigarette smoking, oral contraceptive usage, certain nutritional deficiencies and poor personal hygiene. However, it is not clear whether these factors operate independently from HPV. There is no consistency in the independent effect of these factors on the development of low- to high-grade lesions of cervix. There is a similarity in the patterns of risk between pre-cancerous lesions of the cervix and cervical cancer. Monogamy, late commencement of sexual activity, personal hygiene and use of barrier contraceptive methods help towards primary prevention. In the long-term, primary prevention of cervical neoplasia through HPV immunization of population may be a possibility.

An epidemiologic review of dietary intake studies among American Indians and Alaska Natives: implications for heart disease and cancer risk

PURPOSE

Dietary factors play an important role in the occurrence of heart disease and cancer. While American Indians and Alaska Natives (AIANs) have unique heart disease and cancer mortality profiles, little is known about the effect of diet on heart disease and cancer risk in these populations. This paper reviews existing nutritional intake data from adult AIANs, and considers the potential impact of diet on heart disease and cancer in these communities.

METHODS

A review of the literature was conducted using the Medline database system and other reference materials. Studies documenting nutrient intakes only were included in this review. Studies were limited to those among healthy, non-pregnant adults.

RESULTS

A total of twelve reports from 1959 to 1996 were found. Sample sizes for the studies ranged from 20 to 575 subjects. Most studies were done among women, and a variety of nutritional assessment techniques (24 hour recall, food frequency questionnaire, multiple-day food record) were used. Most studies also had limited nutrient intake data, especially for dietary fiber and vitamin E. The majority of studies reported moderately high intakes of fat and saturated fat, and low intakes of polyunsaturated fat and fiber.

CONCLUSIONS

Based on the limited data, diet may play an important role in the heterogeneity of heart disease and cancer mortality in AIAN communities. More research is needed to assess the impact of diet on heart disease and cancer risk, including more longitudinal data, and data to assess the validity and reliability of traditional methods of dietary assessment.

Walking the journey of womanhood: Yakama Indian women and Papanicolaou (Pap) test screening

Cervical cancer is the second leading cancer among Alaska Native, American Indian women, who have a high incidence of cervical cancer and low survival rates (Boss, 1991; Michalek & Mahoney, 1990; Page & Asire, 1985). The purpose of this Grounded Theory study was to gain a greater understanding of the meaning of the papanicolaou (Pap) test to the Yakama Indian women of eastern Washington to support the Tribe in the design of effective screening interventions. Data from 15 interviews, focus groups, and participant observation were included in the data analysis. The major theme was: Walking the Journey of Womanhood. Four phases of the journey were identified: (a) Starting the Journey, (b) Blooming, (c) Heading the Household, and (d) Becoming an Elder. In this study we found that interventions to influence Pap test screening among the Yakama women must address structures of care, provider-patient communications, and education for the women. Women heading the households and elders were identified as priority populations for education because they have negative attitudes from previous experiences and have a great influence on the younger women. Messages need to be wellness oriented and traditional methods of education, such as the talking circle, role model, and storytelling, need to be used.

Decreasing rates of cervical cancer among American Indians and Hispanics in New Mexico (United States)

Minority women in New Mexico (United States)--including American Indian and Hispanic women--have shown disproportionately high incidence rates of invasive cervical cancer during the 1960s and 1970s. Several public health programs in New Mexico were directed toward early detection of cervical cellular abnormalities, particularly targeting the state's minority women. To evaluate the effectiveness of these programs, we examined the New Mexico Surveillance, Epidemiology, and End Results (SEER) data collected from 1969-92, and calculated average annual, age-specific, and age-adjusted incidence rates by ethnic group (American Indian, Hispanic, and non-Hispanic White) for five-year time intervals. We also calculated age-adjusted mortality rates for cervical cancer in the same ethnic groups using state vital records. Age-adjusted incidence rates for invasive cervical cancer show substantial temporal decreases, especially for minority women in the state. The age-adjusted incidence rate decreased by 66 percent, from 30.3 to 10.3 per 100,000 for American Indian women, and by 61 percent, from 26.1 to 10.2 per 100,000 for Hispanic women. A stage shift to earlier stages of cervical neoplasia occurred over the study period, with a substantially higher proportion of in situ compared with invasive cancers diagnosed in the most recent cf the most remote time period. The ratio of incidence rates of in situ to invasive cancers changed dramatically for both American Indian and Hispanic women. Cervical cancer mortality rates decreased steadily among Hispanic women from 1958 to 1992; the decrease among American Indian women was less stable and fluctuated due to small numbers. Ongoing targeted screening programs should help to reduce cervical cancer incidence and mortality further in New Mexico.

Folate and cancer: A review of the literature

Folate, a water-soluble vitamin, part of the vitamin B complex, plays an important role in methylation reactions and DNA/RNA synthesis. This review examines the experimental and epidemiological evidence for the association between folate status and risk of cancer. Data have accumulated indicating that low folate status may promote carcinogenesis. Low folate levels are associated with cytogenetic abnormalities in vivo and in vitro. Findings from animal studies are conflicting and suggest that the effect of folate on neoplasia depends on factors such as the animal and tumor model, the type, timing, dose, and length of application of carcinogen, the stage of carcinogenesis, and the level and form of folate administered. Epidemiological studies examined the association between folate and cancer of the cervix, colorectum, lung, esophagus, and brain and suggest that low folate status may play an important role early in the neoplastic process. The potential for inhibition of precursor lesions in the cervix and colorectum, namely, cervical intraepithelial neoplasia and adenomatous polyps, respectively, is of particular interest. Additional research designed to clarify the role of folate in carcinogenesis is warranted.

Folate status, women's health, pregnancy outcome, and cancer

Key observations by Dr. Lucy Wills 65 years ago have led to the identification of folate as a nutrient essential for the prevention of megaloblastic anemia of pregnancy. The more recently discovered relationships of folate status to cervical dysplasia, neural tube defects, and atherosclerosis are reviewed here.