AAP-母乳喂养与龋齿

DOI: 10.1542/peds.2006-0124 2007;120;e944-e952 Pediatrics Hiroko Iida, Peggy Auinger, Ronald J. Billings and Michael Weitzman United States Association Between Infant Breastfeeding and Early Childhood Caries in the http://www.pediatrics.org/cgi/content/full/120/4/e944 located on the World Wide Web at: The online version of this article, along with updated information and services, is rights reserved. Print ISSN: 0031-4005. Online ISSN: 1098-4275. Grove Village, Illinois, 60007. Copyright © 2007 by the American Academy of Pediatrics. All and trademarked by the American Academy of Pediatrics, 141 Northwest Point Boulevard, Elk publication, it has been published continuously since 1948. PEDIATRICS is owned, published, PEDIATRICS is the official journal of the American Academy of Pediatrics. A monthly by on February 24, 2011 www.pediatrics.orgDownloaded from ARTICLE Association Between Infant Breastfeeding and Early Childhood Caries in the United States Hiroko Iida, DDS, MPHa, Peggy Auinger, MSb, Ronald J. Billings, DDS, MSDa, Michael Weitzman, MDc,d Departments of aDentistry and bPediatrics, School of Medicine and Dentistry, University of Rochester, Rochester, New York; cDepartment of Pediatrics, School of Medicine, New York University, New York, New York; dAmerican Academy of Pediatrics Julius B. Richmond Center of Excellence The authors have indicated they have no financial relationships relevant to this article to disclose. ABSTRACT OBJECTIVE. Despite limited epidemiologic evidence, concern has been raised that breastfeeding and its duration may increase the risk of early childhood caries. The objective of this study was to assess the potential association of breastfeeding and other factors with the risk for early childhood caries among young children in the United States. METHODS. Data about oral health, infant feeding, and other child and family char- acteristics among children 2 to 5 years of age (N � 1576) were extracted from the 1999–2002 National Health and Nutrition Examination Survey. The association of breastfeeding and its duration, as well as other factors that previous research has found associated with early childhood caries, was examined in bivariate analyses and by multivariable logistic and Poisson regression analyses. RESULTS. After adjusting for potential confounders significant in bivariate analyses, breastfeeding and its duration were not associated with the risk for early childhood caries. Independent associations with increased risk for early childhood caries were older child age, poverty, being Mexican American, a dental visit within the last year, and maternal prenatal smoking. Poverty and being Mexican American also were independently associated with severe early childhood caries, whereas char- acteristics that were independently associated with greater decayed and filled surfaces on primary teeth surfaces were poverty, a dental visit within the last year, 5 years of age, and maternal smoking. CONCLUSIONS. These data provide no evidence to suggest that breastfeeding or its duration are independent risk factors for early childhood caries, severe early childhood caries, or decayed and filled surfaces on primary teeth. In contrast, they identify poverty, Mexican American ethnic status, and maternal smoking as in- dependent risk factors for early childhood caries, which highlights the need to target poor and Mexican American children and those whose mothers smoke for early preventive dental visits. www.pediatrics.org/cgi/doi/10.1542/ peds.2006-0124 doi:10.1542/peds.2006-0124 KeyWords breastfeeding, early childhood caries, maternal smoking Abbreviations ECC—early childhood caries S-ECC—severe early childhood caries NHANES—National Health and Nutrition Examination Survey dfs—decayed and filled surfaces on primary teeth aOR—adjusted odds ratio CI—confidence interval IDR—incidence density ratio FPL—federal poverty level Accepted for publication Mar 14, 2007 Address correspondence to Hiroko Iida, DDS, MPH, Bureau of Dental Health, New York State Department of Health, ESP, Corning Tower, Room 542, Albany, NY 12237-0619. E-mail: hiroko.iida@gmail.com PEDIATRICS (ISSN Numbers: Print, 0031-4005; Online, 1098-4275). Copyright © 2007 by the American Academy of Pediatrics e944 IIDA et al by on February 24, 2011 www.pediatrics.orgDownloaded from THE AMERICAN ACADEMY of Pediatrics identifies hu-man milk as the ideal nutrient for infants1 on the basis of the extensive scientific evidence demonstrating that breastfeeding and the use of human milk provide multiple health-related advantages to infants, mothers, and society.1,2 Breastfeeding is recommended by pedia- tricians and other health care professionals to be contin- ued for at least the first year of life and beyond, for as long as mutually desired by mother and child.1 Pro- longed and unrestricted breastfeeding, however, has been reported to be a potential risk factor for early childhood caries (ECC),3–6 and a recent animal study, the results of which were recently published in this journal, found breast milk to be more cariogenic than bovine milk.7 However, epidemiologic evidence linking infant breastfeeding and its duration and ECC in children is very limited. The purpose of this study was to use na- tionally representative data about children to assess the potential association of breastfeeding and its duration, as well as the association of other factors that there is reason to believe may contribute to ECC, with the risk for ECC among young children in the United States. MATERIALS ANDMETHODS Data from the 1999–2002 National Health and Nutrition Examination Survey (NHANES),8 a cross-sectional sur- vey conducted by the National Center for Health Statis- tics, Centers for Disease Control and Prevention, were analyzed for 1576 children 2 to 5 years of age with information on both infant feeding and oral health. The NHANES includes a household interview with informa- tion regarding numerous aspects of children’s diet, nu- trition and oral health behavior, and family socioeco- nomic characteristics completed by the person most knowledgeable about the child, usually the mother. Re- sults of dental examinations also are included as part of this survey. Infant Breastfeeding Data Information about infant feeding was obtained from par- ents/guardians of children during an in-person inter- view based on retrospective recall. The definition of the various breastfeeding categories used in this study was based on the schema developed by the Interagency Group for Action on Breastfeeding in 1988.9 Breastfeed- ing and its duration (overall, full, and exclusive) were examined by using the following criteria: whether the child was ever breastfed (history of breastfeeding), the age when the child completely stopped breastfeeding or being fed breast milk (overall breastfeeding duration), the age when the child was first fed something other than breast milk or water (exclusive breastfeeding dura- tion), and the age when the child was first fed formula, milk, or solid foods on a daily basis (full breastfeeding duration). Children who consumed only breast milk, with or without the consumption of water, were in- cluded in the assessment of exclusive breastfeeding du- ration although, most conservatively, exclusive breast- feeding often refers to the period when infants do not consume anything other than breast milk. This decision was based on limitations of the NHANES data and the fact that there are no data to suggest that the consump- tion of water is a risk factor for dental caries. ECC, Severe ECC, and Decayed or Filled Primary Tooth Surfaces Count Data A dental examination was performed for children aged �2 years by a trained and calibrated dentist in a medical examination center. Dental caries, that is, decayed or filled primary tooth surfaces (dfs), was assessed by means of a visual/tactile examination without radio- graphs.10 The American Academy of Pediatric Dentistry defines ECC and severe ECC (S-ECC) as follows11: ECC is the presence of �1 decayed, missing (because of caries), or filled primary tooth surfaces (dmfs) in any primary tooth in a child �71 months of age. S-ECC is defined as any sign of smooth-surface caries in children�3 years of age; �1 cavitated, missing (because of caries), or filled smooth surface in primary maxillary anterior teeth from ages 3 through 5 years; or the presence of �1 decayed, missing (because of caries), or filled primary tooth sur- faces of�4 at age 3 years,�5 at age 4 years, or�6 at age 5 years. The reasons for missing primary teeth were not identified in the NHANES data. Hence, in this study, ECC refers to the presence of any dfs on any primary tooth and S-ECC refers to the presence of dfs on any maxillary incisor in children 2 to 5 years of age. The total dfs count was used as a measure of disease severity. Other Variables Investigated Other potential associations with ECC, S-ECC, and dfs count were analyzed, including birth weight, age, gen- der, race/ethnicity, poverty status, maternal age at child’s birth, maternal history of smoking during preg- nancy, history of admission to a NICU, and time since last dental visit. Information about these factors was obtained through the household interview. As discussed further in “Discussion,” each of these factors was in- cluded because of previous research indicating their as- sociation with dental caries or breastfeeding.12–17 Statistical Analyses The prevalence of children with ECC, S-ECC, and mean dfs count was calculated to assess the association of caries with the history and duration of breastfeeding (overall, full, and exclusive) and selected other factors. �2 tests, t tests, and analyses of variance were performed to assess statistical significance. Logistic regression mod- els were performed with the outcomes of ECC and S- ECC (any versus none) to assess the independent asso- ciation of breastfeeding while controlling for potential confounders found in the bivariate (unadjusted) analy- PEDIATRICS Volume 120, Number 4, October 2007 e945 by on February 24, 2011 www.pediatrics.orgDownloaded from ses (P � .10). Similarly, Poisson regression models were analyzed with dfs count as the outcome. Adjusted odds ratios (aORs) and incidence density ratios (IDRs) were calculated for each, respectively. The IDR is the ratio of the incidence rate among exposed to that of unexposed children. An IDR of unity indicates that a covariate is not associated with the dependent variable (dfs count). All of the potential confounders included in the models were categorical variables; therefore, each AOR and IDR com- pares the association of a particular category to a refer- ence category for each covariate. Interactions with breastfeeding were included in secondary analyses; however, results are based on the models with only the main effects. Because the NHANES uses a complex, mul- tistage sampling design, SUDAAN software (Research Triangle Institute, Research Triangle Park, NC)18 was used to estimate appropriate variances for all of the analyses, including bivariate analyses and multivariable logistic and Poisson regressions.19 Results were weighted to be representative of 2- to 5-year-olds in the United States according to the sampling weights that are pro- vided by the NHANES.19 RESULTS Not shown in the tables are the following findings about sociodemographic characteristics of children according to breastfeeding category: children reported to have been breastfed were more likely to be nonblack, living at or above 200% of the federal poverty level (FPL), and born to older mothers who were less likely to report smoking during pregnancy (P � .001 for each). Those exclusively breastfed for �9 months were more likely to be normal birth weight and Mexican American, whereas children who were breastfed overall for a year or longer were more likely to be Mexican American and born to mothers who did not smoke during pregnancy (P � .05 for each). The majority of breastfed children (�75%) were introduced to something other than breast milk or water by age 3 to 6 months. Sample characteristics and the results of bivariate analyses are shown in Table 1. Overall, 27.5% of 2- to 5-year-old-children had ECC (any dfs), and 10% had S-ECC (any dfs on maxillary incisors). Approximately 60% of children were reported as having ever been breastfed, and overall such children had lower rates of ECC and S-ECC compared with those never breastfed. Children breastfed overall for �1 year were more likely to experience ECC than children who were breastfed for �1 year (32.8% vs 22.5%; P � .01; data not shown in tables), whereas there was no statistically significant dif- ference in rates of ECC between those exclusively breastfed for �9 months compared with those exclu- sively breastfed for �9 months (19.5% vs 25.4%; P � .36; data not shown in tables). ECC rates increased with age, whereas S-ECC rates did not. Family income and child race/ethnicity both were associated with ECC and S-ECC, with rates of both highest among those living below the FPL and lowest among those living at �200% of the FPL. Mexican American children had the highest rates of both ECC and S-ECC, followed by non-Hispanic black children and non-Hispanic white children, with children of other race/ethnicities having the lowest rates. Prenatal mater- nal smoking was associated with increased rates of ECC but not with rates of S-ECC. Overall, 36.3% of children who had a dental visit in the last year had ECC, whereas the percentage of children who had ECC and did not have a dental visit within the last year was only 18.5%. In logistic regression analyses conducted to identify factors independently associated with ECC (Table 2), a history of ever having been breastfed was not associated with rates of ECC. In contrast, independent risks for ECC were increased child age, Mexican American ethnicity, living below the FPL, maternal prenatal smoking, and having had a dental visit within the last year. Factors independently associated with an increased risk for S-ECC are shown in Table 3 and include Mexican American ethnicity and living at �200% of the FPL, whereas a history of ever having been breastfed was not associated with rates of S-ECC. Table 4 shows results of multivariable analyses that demonstrate that breastfeed- ing duration, whether overall, full, or exclusive, is not associated with either reduced or increased risk of ECC or S-ECC. Overall, the mean dfs count was 2.4. Poisson regres- sion models that included the child’s birth weight, age, race/ethnicity, poverty status, maternal age at child’s birth, maternal smoking during pregnancy, and time since last dental visit were used to assess the association between infant breastfeeding and dfs counts (Table 5). History of breastfeeding or breastfeeding duration of any type again were not significantly associated with DFS counts, whereas being 5 years old, living below the FPL, maternal smoking during pregnancy, and having a den- tal visit in the past year each were independently asso- ciated with increased dfs counts. Children’s birth weight, race/ethnicity, and maternal age at child’s birth were not associated with increased numbers of caries. Additional regression analyses were performed to at- tempt to better explicate the relationships between breastfeeding status and other factors investigated for associations with ECC, as well as for interaction effects. Breastfeeding was associated with a 40% reduced risk for ECC (aOR: 0.6; 95% confidence interval [CI]: 0.4– 0.9; data not shown in tables) when poverty status, maternal age at child’s birth, and maternal prenatal smoking were excluded from the full model used in Table 2 and similarly was associated with a 40% de- crease in the risk for S-ECC (aOR: 0.6; 95% CI: 0.4–0.9; data not shown in tables) when poverty status and ma- ternal age at child’s birth were removed from the full model used in Table 3. When accounting for interactions e946 IIDA et al by on February 24, 2011 www.pediatrics.orgDownloaded from TABLE 1 Distribution of US Children Aged 2 to 5 Years by Study Variables for ECC and S-ECC (Unadjusted Analysis) Variable ECC S-ECC Sample Size Prevalence, % P Sample Size Prevalence, % P Overall 1576 27.5 1503 10.0 History of breastfeeding 1568 .03 1495 .02 Ever 939 24.9 899 8.2 Never 629 32.3 596 13.5 Overall breastfeeding duration 1562 .01 1489 .02 �1 y 216 32.8 210 11.9 6 mo to�1 y 274 20.6 265 5.4 4 to�6 mo 105 24.9 97 9.6 1 to�4 mo 233 22.2 222 6.0 �1 mo 105 26.6 99 11.6 0 629 32.3 596 13.5 Exclusive breastfeeding duration, mo 1561 .054 1488 .049 �9 57 19.5 55 7.2 6 to�9 166 29.5 160 8.5 3 to�6 311 23.6 299 6.9 �3 398 24.8 378 9.3 0 629 32.3 596 13.5 Full breastfeeding duration, mo 1562 .04 1489 .03 �9 55 25.5 53 9.6 6 to�9 179 27.2 174 7.5 3 to�6 304 24.8 286 6.4 �3 395 23.8 380 9.8 0 629 32.3 596 13.5 Birth weight, g 1517 .63 1448 .02 Very low (�1500) 24 17.3 23 2.2 Low (1500–2499) 124 29.2 118 9.1 Normal (�2500) 1369 27.6 1307 10.1 Age, y �.001 .22 2 495 10.9 487 7.6 3 381 20.9 370 10.1 4 362 34.4 347 10.8 5 338 44.3 299 11.7 Gender .49 .99 Male 793 28.7 751 10.0 Female 783 26.3 752 10.0 Race/ethnicity �.001 �.001 Non-Hispanic white 489 25.3 477 7.9 Non-Hispanic black 456 31.8 427 13.9 Mexican American 478 41.9 458 17.9 Other 153 17.3 141 7.2 Poverty status, % FPL 1408 �.001 1342 �.001 �100 511 41.3 478 18.6 100 to�200 395 27.9 377 11.2 �200 502 17.2 487 4.4 Maternal age at child’s birth, y 1570 �.001 1498 .01 �19 253 38.5 237 18.5 20–29 839 29.3 804 10.1 �30 478 21.6 457 7.4 Maternal smoking during pregnancy 1563 .01 1491 .21 Yes 226 38.4 217 14.1 No 1337 25.3 1274 9.1 NICU 1568 .73 1495 .29 Yes 175 28.7 165 13.2 No 1393 27.3 1330 9.4 Time since last dental visit 1508 �.001 1445 .26 �1 y 672 36.3 619 11.3 �1 y 836 18.5 826 8.6 ECC includes any DFS score (�1), and S-ECC includes any DFS score (�1) on maxillary incisors. Source: NHANES, 1999–2002.8 PEDIATRICS Volume 120, Number 4, October 2007 e947 by on February 24, 2011 www.pediatrics.orgDownloaded from of breastfeeding and other factors included in the full model, breastfed Mexican American children were at greater risk for ECC than non-Hispanic white children who were never breastfed (aOR: 2.1; 95% CI: 1.1–3.8), and breastfed children living below the FPL were also more likely to experience ECC than children living in families at �200% of the FPL who had never been breastfed (aOR: 3.2; 95% CI: 1.4–7.3). DISCUSSION Although Bowen and Lawrence,7 using a desalivated rat model, reported recently that human breast milk was more cariogenic than bovine milk, epidemiologic data on breastfeeding and caries risk are quite limited. Breast- feeding and dental caries among children aged 2 through 5 years was studied previously using data from 1988 to 1994, and no association was found.16 In the current study, using more recent data and more detailed cate- gorization of breastfeeding duration and type, the poten- tial association of the duration of exclusive breastfeeding and breastfeeding accompanied by additional supple- mental feedings that potentially contained sucrose were investigated. The findings indicate that infant breast- feeding and its duration, whether overall, full, or exclu- sive, is not associated with any increased risk for ECC or S-ECC. In contrast, poverty, Mexican American ethnic sta- tus, and maternal smoking during pregnancy were each found to be independently associated with ECC. Several previous studies reported findings similar to those reported in this article concerning the association between various aspects of breastfeeding and ECC.20–23 Although breastfeed- ing was not found to be associated with either an increased or decreased risk of ECC, decreased family income and prenatal maternal smoking, both strongly associated with decreased rates of breastfeeding as demonstrated in previ-