The role of oral hygiene in head and neck cancer: results from International Head and Neck Cancer Epidemiology (INHANCE) consortium.

BACKGROUND: Poor oral hygiene has been proposed to contribute to head and neck cancer (HNC) risk, although causality and independency of some indicators are uncertain. This study investigates the relationship of five oral hygiene indicators with incident HNCs. METHODS: In a pooled analysis of 8925 HNC cases and 12 527 controls from 13 studies participating in the International Head and Neck Cancer Epidemiology Consortium, comparable data on good oral hygiene indicators were harmonized. These included: no denture wear, no gum disease (or bleeding), <5 missing teeth, tooth brushing at least daily, and visiting a dentist ≥once a year. Logistic regression was used to estimate the effects of each oral hygiene indicator and cumulative score on HNC risk, adjusting for tobacco smoking and alcohol consumption. RESULTS: Inverse associations with any HNC, in the hypothesized direction, were observed for <5 missing teeth [odds ratio (OR) = 0.78; 95% confidence interval (CI) 0.74, 0.82], annual dentist visit (OR = 0.82; 95% CI 0.78, 0.87), daily tooth brushing (OR = 0.83, 95% CI 0.79, 0.88), and no gum disease (OR = 0.94; 95% CI 0.89, 0.99), and no association was observed for wearing dentures. These associations were relatively consistent across specific cancer sites, especially for tooth brushing and dentist visits. The population attributable fraction for ≤ 2 out of 5 good oral hygiene indicators was 8.9% (95% CI 3.3%, 14%) for oral cavity cancer. CONCLUSION: Good oral hygiene, as characterized by few missing teeth, annual dentist visits, and daily tooth brushing, may modestly reduce the risk of HNC.

Vitamin E intake from natural sources and head and neck cancer risk: a pooled analysis in the International Head and Neck Cancer Epidemiology consortium.

BACKGROUND: Evidence for the possible effect of vitamin E on head and neck cancers (HNCs) is limited. METHODS: We used individual-level pooled data from 10 case-control studies (5959 cases and 12 248 controls) participating in the International Head and Neck Cancer Epidemiology (INHANCE) consortium to assess the association between vitamin E intake from natural sources and cancer of the oral cavity/pharynx and larynx. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression models applied to quintile categories of non-alcohol energy-adjusted vitamin E intake. RESULTS: Intake of vitamin E was inversely related to oral/pharyngeal cancer (OR for the fifth vs the first quintile category=0.59, 95% CI: 0.49-0.71; P for trend <0.001) and to laryngeal cancer (OR=0.67, 95% CI: 0.54-0.83, P for trend <0.001). There was, however, appreciable heterogeneity of the estimated effect across studies for oral/pharyngeal cancer. Inverse associations were generally observed for the anatomical subsites of oral and pharyngeal cancer and within covariate strata for both sites. CONCLUSION: Our findings suggest that greater vitamin E intake from foods may lower HNC risk, although we were not able to explain the heterogeneity observed across studies or rule out certain sources of bias.

The INHANCE consortium: toward a better understanding of the causes and mechanisms of head and neck cancer.

The International Head and Neck Cancer Epidemiology (INHANCE) consortium is a collaboration of research groups leading large epidemiology studies to improve the understanding of the causes and mechanisms of head and neck cancer. The consortium includes investigators of 35 studies who have pooled their data on 25 500 patients with head and neck cancer (i.e., cancers of the oral cavity, oropharynx, hypopharynx, and larynx) and 37 100 controls. The INHANCE analyses have confirmed that tobacco use and alcohol intake are key risk factors of these diseases and have provided precise estimates of risk and dose response, the benefit of quitting, and the hazard of smoking even a few cigarettes per day. Other risk factors include short height, lean body mass, low education and income, and a family history of head and neck cancer. Risk factors are generally similar for oral cavity, pharynx, and larynx, although the magnitude of risk may vary. Some major strengths of pooling data across studies include more precise estimates of risk and the ability to control for potentially confounding factors and to examine factors that may interact with each other. The INHANCE consortium provides evidence of the scientific productivity and discoveries that can be obtained from data pooling projects.

Characterization of a distinct nuclear acidic protein antigen (MA) and clinical findings in systemic lupus erythematosus patients with MA antibodies.

Circulating antibodies against certain nuclear acidic protein antigens have been shown to have diagnostic and prognostic importance in connective tissue disease. We describe a new precipitin system found in the sera of patients with systemic lupus erythematosus. The antigen, called MA, was prepared from calf thymus nuclei, and was shown to be distinct from other nuclear acidic protein antigens by physicochemical and immunologic techniques. MA antibodies were detected in the serum of 12 of 66 lupus patients and in none of 554 sera from normal controls or patients with other rheumatic diseases. Lupus patients having MA antibodies had more severe disease than did lupus patients with Sm or native DNA antibodies, manifested by recalcitrant skin rashes and a significantly greater incidence of hypocomplementemia, serious renal disease, hypertension, hepatosplenomegaly, lymphadenopathy, and neurological disease (P values range from 0.025 to 0.005). The presence of circulating MA antigen was demonstrated in three lupus patients immediately before a flare of nephritis. These data suggest that MA is a nuclear acidic protein antigen that may identify a subset of lupus patients with very severe disease. The presence of the antigen in the circulation before clinical flares suggests a possible biologic role for the MA system in an immune complex nephritis.

Oral cancer and mouthwash.

As part of a case-control study in North Carolina involving 206 women with oral and pharyngeal cancers and 352 controls, questions were asked concerning the patterns of mouthwash use. No significant overall increase in risk was found among users; the relative risk, adjusted for snuff dipping and smoking habits, was 1.15 [lower, upper limits of the 95% confidence interval (95% Cl) = 0.8, 1.7]. The relative risk associated with mouthwash use was increased to 1.94 (95% Cl = 0.8, 4.7), however, among women abstaining from tobacco. Although consistent dose-response relationships were not observed for this subgroup, these findings and other reports of an increased risk among persons ordinarily at low risk of this disease raise the possibility that mouthwash may contribute to oral and pharyngeal cancers.

Dietary factors in oral and pharyngeal cancer.

A population-based case-control study of oral and pharyngeal cancer conducted in four areas of the United States provided information on a number of risk factors, including diet. Interviews were obtained from 871 oral cancer patients and 979 controls among whites, frequency matched for age and sex. Consumption frequency of 61 food items was assessed in the questionnaire; attention was given to foods that are sources of vitamins A and C and carotene. The major finding was an inverse relationship between fruit intake and risk of oral and pharyngeal cancer; individuals in the highest quartile of intake had about half the risk of those in the lowest quartile. Vitamin C, carotene, or fiber in fruit did not appear to account completely for this relationship, since these nutrients in vegetables did not provide similar protection. This finding suggests the influence of other constituents in fruits, although it is possible that cooking vegetables may have a nutrient-diminishing effect. Dietary intake of other nutrients, such as the B vitamins, vitamin E, folate, and iron, showed no consistent relationship to risk of oral and pharyngeal cancer. Coffee or other hot beverage consumption did not increase risk; intake of nitrite-containing meats or cooking practices, such as smoking, pickling, or charcoal grilling, also did not increase risk. All analyses were adjusted for the effects of tobacco and alcohol, strong risk factors for oral and pharyngeal cancer. Dietary findings among the few subjects who did not use tobacco or alcohol were similar to those for all subjects.

Racial differences in risk of oral and pharyngeal cancer: alcohol, tobacco, and other determinants.

BACKGROUND: In the United States, Blacks have increasingly higher rates of oral and pharyngeal cancer (oral cancer) than Whites, but determinants of the racial disparity have not been clear. PURPOSE: The purpose of this study was to explore reasons for the higher incidence of oral cancer among Blacks than Whites. METHODS: We used data from a large, population-based case-control study of oral cancer risk factors conducted in four areas of the United States. On the basis of interviews that ascertained characteristics of 1065 oral cancer patients (871 Whites and 194 Blacks) and 1182 controls (979 Whites and 203 Blacks), we examined racial differences in exposure prevalences and relative risks for a number of known etiologic factors, including tobacco and alcohol consumption, diet, and socioeconomic and other variables. To evaluate the extent to which the major risk factors explained the excess risk of oral cancer among Blacks, population-attributable risks were calculated. RESULTS: Differences with respect to alcohol consumption, especially among current smokers, emerged as the most important explanatory variables. After adjusting for smoking, heavy drinking (> or = 30 drinks/week) resulted in a 17-fold increased risk among Blacks and a ninefold increase among Whites. Among drinkers, Blacks tended to drink more than Whites. Also, a higher (P = .01) percentage of Blacks (37%) than Whites (28%) were current smokers, although there were little or no racial differences in relative risks or patterns of use for other smoking variables, including number of cigarettes smoked per day, years of smoking, and age started smoking. From population-attributable risk calculations, we estimated that differences in alcohol and tobacco use account for the bulk of the higher incidence of oral cancer among Blacks in the United States and that, in the absence of alcohol and tobacco, the rates of this cancer according to race (Black, White) and gender would be nearly equal. With regard to other potential etiologic factors, protective effects provided by higher dietary intake of fruits and vitamin C were more pronounced for Whites, while Blacks more often tended to be in sociodemographic and medical or dental health categories associated with increased risk. CONCLUSIONS: These analyses provide evidence that various environmental or lifestyle determinants of oral cancer may contribute to the higher oral cancer rates in Blacks than in Whites in the United States, but that patterns and risks associated with alcohol consumption, particularly among current smokers, are the most important contributors to the excess risk in Blacks. IMPLICATIONS: These findings suggest that the key to prevention of oral and pharyngeal cancers among both Blacks and Whites is reduced intake of alcoholic beverages and, because of strong interactive effects, the cessation of smoking.

Alcohol dehydrogenase 3 genotype and risk of oral cavity and pharyngeal cancers.

BACKGROUND: The consumption of alcoholic beverages is a strong risk factor for cancers of the oral cavity and pharynx (oral cancers). Alcohol dehydrogenase type 3 (ADH3) metabolizes ethanol to acetaldehyde, a carcinogen. We evaluated whether individuals homozygous for the fast-metabolizing ADH3(1) allele (ADH3[1-1]) have a greater risk of developing oral cancer in the presence of alcoholic beverage consumption than those with the slow-metabolizing ADH3(2) allele (ADH3[1-2] and ADH3[2-2]). METHODS: As part of a population-based study of oral cancer conducted in Puerto Rico, the ADH3 genotypes of 137 patients with histologically confirmed oral cancer and of 146 control subjects (i.e., individuals with no history of oral cancer) were determined by molecular genetic analysis of oral epithelial cell samples. Risks were estimated by use of multiple logistic regression analyses. RESULTS: Compared with nondrinkers with the ADH3(1-1) genotype, consumers of at least 57 alcoholic drinks per week with the ADH3(1-1), ADH3(1-2), and ADH3(2-2) genotypes had 40.1-fold (95% confidence interval [CI] = 5.4-296.0), 7.0-fold (95% CI = 1.4-35.0), and 4.4-fold (95% CI = 0.6-33.0) increased risks of oral cancer, respectively; the risk associated with the ADH3(1-1) genotype, compared with the ADH3(1-2) and ADH3(2-2) genotypes combined, was 5.3 (95% CI = 1.0-28.8) among such drinkers. Considering all levels of alcohol consumption, the risk of oral cancer per additional alcoholic drink per week increased 3.6% (95% CI = 1.9%-5.4%) for subjects with the ADH3(1-1) genotype and 2.0% (95% CI = 0.9%-3.0%) for subjects with the ADH3(1-2) or ADH3(2-2) genotype (two-sided P = .04). CONCLUSIONS: The ADH3(1-1) genotype appears to substantially increase the risk of ethanol-related oral cancer, thus providing further evidence for the carcinogenicity of acetaldehyde.

Diet in the etiology of oral and pharyngeal cancer among women from the southern United States.

A case-control interview study involving 227 women in North Carolina with oral cavity or pharyngeal cancer and 405 matched controls showed a protective effect of a usual adult diet high in fruits and vegetables. The relative risks of 0.65 for moderate and 0.52 for high (relative to 1.0 for infrequent) consumption of fruits and vegetables were statistically significant and remained after controlling for demographic characteristics, tobacco and alcohol use, relative weight, and intake of other food groups. Risks were lower with higher bread and cereal intake but higher for those women with the lightest weights, adjusted for height. The inverse associations between oral and pharyngeal cancer and intake of fruits and vegetables and intake of breads and cereals could not be attributed to an association with general nutritional status, since meat and fish consumption was related to an increased risk of oral and pharynx cancer. Moreover, dairy and egg consumption was generally unrelated to cancer risk. The reduction in risk with greater fruit and vegetable consumption is consistent with the hypothesis that vitamin C and/or beta-carotene intake is associated with a reduced risk of oral and pharyngeal cancer.

Mouthwash use and oral conditions in the risk of oral and pharyngeal cancer.

Interviews with 866 patients with cancer of the oral cavity and pharynx and 1249 controls of similar age and sex from the general population in four areas of the United States revealed increased risks associated with the regular use of mouthwash. Risks of oral cancer were elevated by 40% among male and 60% among female mouthwash users, after adjusting for tobacco and alcohol consumption. Risks among both sexes generally increased in proportion to duration and frequency of mouthwash use. The increased risks were confined to users of mouthwash high in alcohol content, consistent with the elevated risks associated with drinking alcoholic beverages. Except for a higher prevalence of leukoplakia among cases, little relationship was found with oral or dental conditions, although denture wearing was reported more often by patients with cancer of the gums. These findings, together with other studies, provide further incentive for clarifying the association between mouthwash use and oral cancer.

Smoking and drinking in relation to oral and pharyngeal cancer.

A case-control study of oral and pharyngeal cancer conducted in four areas of the United States provided information on the tobacco and alcohol use of 1114 patients and 1268 population-based controls. Because of the large study size, it could be shown that the risks of these cancers among nondrinkers increased with amount smoked, and conversely that the risks among nonsmokers increased with the level of alcohol intake. Among consumers of both products, risks of oropharyngeal cancer tended to combine more in a multiplicative than additive fashion and were increased more than 35-fold among those who consumed two or more packs of cigarettes and more than four alcoholic drinks/day. Cigarette, cigar, and pipe smoking were separately implicated, although it was shown for the first time that risk was not as high among male lifelong filter cigarette smokers. Cessation of smoking was associated with a sharply reduced risk of this cancer, with no excess detected among those having quit for 10 or more years, suggesting that smoking affects primarily a late stage in the process of oropharyngeal carcinogenesis. The risks varied by type of alcoholic beverage, being higher among those consuming hard liquor or beer than wine. The relative risk patterns were generally similar among whites and blacks, and among males and females, and showed little difference when oral and pharyngeal cancers were analyzed separately. From calculations of attributable risk, we estimate that tobacco smoking and alcohol drinking combine to account for approximately three-fourths of all oral and pharyngeal cancers in the United States.

Evaluation of 2-week doctor visit reporting in the national health interview survey.

This report includes a review of previous research on the reporting of ambulatory medical visits in household surveys, describes the methods used in the Health Interview Evaluation Survey, and presents results relating to the reporting of 2-week doctor visits.

Diet and nutrition in the etiology of oral cancer.

Epidemiological studies worldwide have implicated dietary and nutritional factors in the development of oral and pharyngeal cancer. Dietary information in these case-control studies generally was collected through food-frequency questionnaires. Consistently, these studies observed a protective effect of a diet high in fruit intake, reflected in a 20-80% reduction in oral cancer risk. A high intake of foods considered to be dietary staples in particular cultural groups, possibly indicating a generally impoverished diet, has been linked to excess risk. Indigenous dietary practices that in single studies were found to increase risk include a high intake of chili powder and wood stove cooking. Supplementation with various vitamins has been protective in a few studies. Chemoprevention trials generally have found that chemopreventive agents reduce the size of oral leukoplakia lesions or the frequency of second primary oral cancers. The most consistent dietary findings across multiple cultural settings are a protective effect of high fruit consumption and the carcinogenic effect of high alcohol intake.

A case-control study of the etiology of Ewing's sarcoma.

An interview case-control study was undertaken to search for risk factors for Ewing's sarcoma. The 208 cases, aged 5 months to 22 years at diagnosis and all white but one, were identified from hospitals participating in the Intergroup Ewing's Sarcoma Study therapeutic trials. Two controls were sought for each case: a sibling control and an age-matched regional population control identified through random-digit dialing telephone procedures. A questionnaire was administered to the parents of cases and controls. Parents were more likely to have smoked during the pregnancy with the case than during the pregnancy with the unaffected sibling. Risks rose with the number of cigarettes the mother smoked per day during the pregnancy. Concepti exposed to less than 1 pack/day were at 3.2 times the risk, and those exposed to 1 pack or more were at 6.7 times the risk of the nonexposed. However, risks associated with smoking were lower and not statistically significant in analyses using the region-matched controls. Hernias, mostly umbilical and inguinal, were diagnosed six times more frequently among the cases compared to region-matched controls. However, hernias occurred in just 10% of cases, and the matched siblings had hernias diagnosed with the same frequency as the cases. An apparent excess of heart disorders among cases versus siblings seems likely to be an artifact of increased medical surveillance of cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Health conditions among the currently employed.

This report presents national estimates of the prevalence and incidence of selected health conditions and their work-related consequences among currently employed persons 18 years of age and over. The major health conditions presented include back pain; hand discomfort; dermatitis; eye, nose, and throat irritation; and work injuries. Also presented are estimates of the distribution of workers on selected physical activities and exposures at work. Data are presented by age, sex, race, ethnicity, education, and broad occupational category.

The prevalence of dental sealants in the US population: findings from NHANES III, 1988-1991.

Over the past decade, dental sealants have become recognized as an important adjunct to the use of fluorides in the prevention of dental caries. The most recent national survey of oral health in children conducted in 1986-1987 found that only 7.6% of children had any sealed teeth. As part of the oral health component of the 1988-1991 Third National Health and Examination Survey (NHANES III-Phase 1), the prevalence of dental sealants in children, adolescents, and adults was determined. The presence of dental sealants on posterior teeth (excluding third molars) and maxillary lateral incisors was recorded by visual and tactile methods during the dental caries examination. Findings in this paper are based on those examined persons having at least one sealable primary tooth for children aged 2-11 years (n=3,792); at least one sealable premanent tooth for persons aged 18 years and over (n=7,146). During 1988-1991, about 18.5% of US children and youth ages 5-17 had one or more sealed permanent teeth. A significantly higher percentage of non-Hispanic whites had sealants in comparison with their non-Hispanic black and Mexican-American counterparts (for all contrasts, p<0.001). As expected, molar teeth were the most frequently sealed tooth type. Only 1.4% of US children ages 2-11 had at least one sealed primary tooth. The prevalence of dental sealants decreased in the US adult population with increasing age; 5.5% of adults ages 18-24 had at least one sealed permanent tooth. Data collected from NHANES III-Phase 2 (1991-1994) will be analyzed to determine if the upward trend in sealant use continues.

Oral mucosal smokeless tobacco lesions among adolescents in the United States.

The presence of oral smokeless tobacco lesions among adolescents may be an early indicator of increased risk for oral cancers. Data from the 1986-1987 National Survey of Oral Health in US School Children were used to examine the cross-sectional relationship between the use of tobacco and alcohol and the presence of white or whitish oral soft-tissue lesions. The sample included 17,027 schoolchildren (aged 12 to 17 years) who provided information on the use of snuff, chewing tobacco, cigarettes, and alcohol and who received oral clinical examinations. Smokeless tobacco lesions were detected in 1.5% of students (projects to about 300,000 nationally), including 2.9% of males and 0.1% of females. These lesions were more prevalent among whites (2.0%) than among African-Americans (0.2%) or Hispanics (0.8%). Modeling with multivariate logistic regression revealed that, among white males, current snuff use was the strongest correlate of lesions [odds ratio (OR) = 18.4; 95% confidence interval (CI) = 8.5-39.8], followed by current chewing tobacco use [OR = 2.5; 95% CI = 1.3-5.0]. Lesions were strongly associated with duration, monthly frequency, and daily minutes of use of snuff and chewing tobacco. These data suggest that snuff may be a stronger risk factor than chewing tobacco for smokeless tobacco lesions, but the use of either of these forms of oral tobacco exhibits a dose-response relationship with the occurrence of lesions. We found little evidence that the use of alcohol or cigarettes may increase the risk of smokeless tobacco lesions. Preventing smokeless tobacco lesions and their possible malignant transformation may be best accomplished among adolescents by preventing the use of snuff and chewing tobacco.

An overview of the oral health component of the 1988-1991 National Health and Nutrition Examination Survey (NHANES III-Phase 1).

As part of a Federal consortium, the National Institute of Dental Research's (NIDR) Division of Epidemiology and Oral Disease Prevention (DEODP) staff and consultants collaborated with the National Center for Health Statistics (NCHS) to conduct a national oral health examination as a component of the 1988-94 National Health and Nutrition Examination Survey (NHANES III). The Phase 1 took place between October 18, 1988, and October 24, 1991, at 44 survey locations; Phase 2, between September 20, 1991, and October 15, 1994, at 45 sites. This article provides general background information on the NHANES III and its oral health examination component which pertains to all six years of the full survey. It also focuses on particular aspects of the first three years of the survey (NHANES III-Phase 1)--the database for the articles in this peer-reviewed Special Issue--and provides the essential context for the substantively oriented analyses of the Phase 1 database which are presented in the articles which follow this overview.

Coronal caries in the primary and permanent dentition of children and adolescents 1-17 years of age: United States, 1988-1991.

The Third National Health and Nutrition Examination Survey-Phase 1, conducted from 1988 to 1991 in the United States, included an assessment of dental caries in US children and adolescents and provided the opportunity for differences in dental caries status to be viewed by a ge, sex, race, and race-ethnicity. The measurement of dental caries in children and adolescents from 2-17 years of age included the number of decayed, missing, and filled permanent tooth surfaces and teeth, and the number of decayed, and filled primary tooth surfaces and teeth. Additionally, a brief visual inspection for the presence or absence of early childhood caries in the maxillary incisors was conducted for children 12-23 months of age. The survey yielded weighted estimates for 1988-1991 for over 58 million US children and adolescents 1 to 17 years of age. For infants aged 12-23 months, 0.8% were scored positive for early childhood caries. Over 60% (62.1%) of the children aged 2-9 years were caries-free in their primary dentition. Over half (54.7%) of the children 5-17 years were caries-free in their permanent dentition. The occurrence of caries in the permanent dentition is clustered: A quarter of the children and adolescents ages 5 to 17 with at least one permanent tooth accounted for about 80% of the caries experienced in permanent teeth. Differences in caries experience were found among race and race-ethnicity subpopulations, and caries patterns for the primary and permanent dentition were dissimilar. Further analyses are needed to explore other potential determinants of caries in children.

Coronal and root caries in the dentition of adults in the United States, 1988-1991.

Dental public health policy planning requires accurate and current information about the extent of caries in the United States population. These data are available from the caries examination from Phase 1 of the Third National Health and Nutrition Examination Survey, which found that 94% of adults in the United States show evidence of past or present coronal caries. Among the dentate, the mean number of decayed and filled coronal surfaces per person was 21.5. Dentate females had a lower number of untreated coronal tooth surfaces with caries (1.5), but a higher mean number of treated and untreated surfaces per person (22.7) than males, with scores of 2.1 and 20.2, respectively. Estimates for race-ethnicity groups were standarized by age and gender to control for population differences among them. Dentate non-Hispanic blacks (11.9) and Mexican-Americans (14.1) had half the number of decayed and filled coronal surfaces as non-Hispanic whites (24.3), but more untreated surfaces (non-Hispanic whites, 1.5; non-Hispanic blacks, 3.4; Mexican-Americans, 2.8). Mexican-Americans were most likely to be dentate, had the highest average number of teeth, and had 25% fewer decayed, missing, and filled coronal surfaces (37.6) than non-Hispanic blacks (49.2) and non-Hispanic whites (51.0). Root caries affected 22.5% of the dentate population. Blacks had the most treated and untreated root surfaces with caries (1.6), close to the value for Mexican-Americans (1.4). The score for non-Hispanic whites was 1.1. Untreated root caries is most common in dentate non-Hispanic blacks (1.5), followed by Mexican-Americans (1.2), with non-Hispanic whites (0.6) having the fewest untreated carious root surfaces. Race-ethnicity groups were disparate with respect to dental caries; effort is needed to treat active caries common in some population subgroups.