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J D Sargent

Publications and source records attributed to J D Sargent.

At least 19 recordsLinked to original sources
PubMed1999

Do movie stars encourage adolescents to start smoking? Evidence from California.

BACKGROUND: The purpose of this study was to examine the relationship between adolescents' favorite movie stars and their smoking status, controlling for variables associated with smoking initiation. METHODS: The 1996 California Tobacco Survey questioned 6,252 adolescents about their favorite stars, smoking history, exposure to smokers, rebelliousness, knowledge and attitudes regarding smoking, and cigarette advertising and promotion. The top 10 favorite stars were tested for differential preference between ever and never smokers, defined as those who had never puffed on a cigarette. Never smokers were categorized as susceptible or nonsusceptible to smoking. RESULTS: Favorite stars differed significantly among adolescent ever and never smokers. A majority of favorite stars of ever smokers smoked on and off screen compared to favorite stars of never smokers. In multivariate analyses, adolescent never smokers who preferred favorite stars of adolescent ever smokers were significantly more likely to be susceptible to smoking (OR = 1.35; 95% CI 1.12, 1.62), even after adjustment for known predictors of adolescent smoking and demographic variables. This effect was only slightly weaker than that of exposure to friends and family who smoke (OR = 1.45; 95% CI 1.13, 1.85). CONCLUSIONS: This study provides preliminary evidence that stars who smoke on and off screen may encourage youth to smoke.

Adolescent↗
PubMed1999

Randomized trial of calcium glycerophosphate-supplemented infant formula to prevent lead absorption.

BACKGROUND: Although additional dietary calcium is recommended frequently to reduce the risk of lead poisoning, its role in preventing lead absorption has not been evaluated clinically. OBJECTIVE: The objective was to determine the safety and to estimate the size of the effect of calcium- and phosphorus-supplemented infant formula in preventing lead absorption. DESIGN: One hundred three infants aged 3.5-6 mo were randomly assigned to receive iron-fortified infant formula (465 mg Ca and 317 mg P/L) or the same formula with added calcium glycerophosphate (1800 mg Ca and 1390 mg P/L) for 9 mo. RESULTS: There was no significant difference between groups in the mean ratio of urinary calcium to creatinine, serum calcium and phosphorus, or change in iron status (serum ferritin, total iron binding capacity). At month 4, the median (+/-SD) increase from baseline in blood lead concentration for the supplemented group was 57% of the increase for the control group (0.04 +/- 0.09 compared with 0.07 +/- 0.10 micromol/L; P = 0.039). This effect was attenuated during the latter half of the trial, with an overall median increase in blood lead concentration from baseline to month 9 of 0.12 +/- 0.13 micromol/L for the control group and 0.10 +/- 0.18 micromol/L for the supplemented group (P = 0.284). CONCLUSIONS: Supplementation did not have a measurable effect on urinary calcium excretion, calcium homeostasis, or iron status. The significant effect on blood lead concentrations during the first 4 mo was in the direction expected; however, because this was not sustained throughout the 9-mo period we cannot conclude that the calcium glycerophosphate supplement prevented lead absorption in this population.

Calcium↗
PubMed1999

High concentrations of heavy metals in neighborhoods near ore smelters in northern Mexico.

In developing countries, rapid industrialization without environmental controls has resulted in heavy metal contamination of communities. We hypothesized that residential neighborhoods located near ore industries in three northern Mexican cities would be heavily polluted with multiple contaminants (arsenic, cadmium, and lead) and that these sites would be point sources for the heavy metals. To evaluate these hypotheses, we obtained samples of roadside surface dust from residential neighborhoods within 2 m of metal smelters [Torreón (n = 19)] and Chihuahua (n = 19)] and a metal refinery [Monterrey (n = 23)]. Heavy metal concentrations in dust were mapped with respect to distance from the industrial sites. Correlation between dust metal concentration and distance was estimated with least-squares regression using log-transformed data. Median dust arsenic, cadmium, and lead concentrations were 32, 10, and 277 microg/g, respectively, in Chihuahua; 42, 2, and 467 microg/g, respectively, in Monterrey, and 113, 112, and 2,448 microg/g, respectively, in Torreón. Dust concentrations of all heavy metals were significantly higher around the active smelter in Torreón, where more than 90% of samples exceeded Superfund cleanup goals. At all sites, dust concentrations were inversely related to distance from the industrial source, implicating these industries as the likely source of the contamination. We concluded that residential neighborhoods around metal smelting and refining sites in these three cities are contaminated by heavy metals at concentrations likely to pose a health threat to people living nearby. Evaluations of human exposure near these sites should be conducted. Because multiple heavy metal pollutants may exist near smelter sites, researchers should avoid attributing toxicity to one heavy metal unless others have been measured and shown not to coexist.

Arsenic↗
PubMed1999

Diagnostic testing unwarranted for children with blood lead 10 to 14 microg/dL.

BACKGROUND: Recent statements from the American Academy of Pediatrics and Centers for Disease Control and Prevention recommend diagnostic venous blood lead testing within 90 days of a marginally elevated screening test (10-14 microg/dL). OBJECTIVE: To evaluate the ability of a marginally elevated capillary (CScr) or venous (VScr) blood lead screening test to predict venous diagnostic (VPb) blood lead (taken within 90 days of the screening test) that would prompt environmental evaluation (>/=20 microg/dL). DESIGN: Population-based follow-up study comparing CScr and VScr with VPb drawn within 90 days of the screening sample. This study population was drawn from all children aged 0 to 4 years who were screened in Worcester County, Massachusetts, and Providence County, Rhode Island, with CScr and VScr during calendar year 1994. OUTCOME MEASURES: To evaluate predictive validity, CScr and VScr were correlated with VPb. CScr, VScr, and VPb results were then separated into the following categories: <10, 10 to 14, 15 to 19, and >/=20 microg/dL. CScr and VScr categories were cross-tabulated against VPb categories, and logistic regression analysis was used to evaluate categorical elevations of CScr and VScr as predictors of VPb >/=20 microg/dL. RESULTS: Of 31 904 children screened with CScr, 5450 (17.1%) were elevated and 1278 were followed up with VPb within 90 days. Of 14 623 children screened with VScr, 2979 (20.4%) were elevated and 614 were followed up with VPb within 90 days. CScr was only weakly correlated with VPb (r = 0.39), whereas VScr was more strongly correlated with VPb (r = 0.73). Compared with CScr <10 microg/dL, CScr in the 10 to 14 microg/dL range did not identify a higher percentage of children with VPb elevation in any category, and falsely misclassified as lead poisoned some 77% of children. Compared with VScr <10 microg/dL, VScr in the 10 to 14 microg/dL range identified higher percentages of children with VPb in the 10 to 19 microg/dL range but not with VPb >/=20 microg/dL, and falsely misclassified as lead poisoned 42% of children. Compared with screening tests <10 microg/dL, the odds of identifying a child with VPb >/=20 were no different from 1 for CScr of 10 to 14 microg/dL (adjusted odds ratio 1.4 [95% confidence interval 0.3, 6.6]), CScr of 15 to 19 microg/dL (3.2 [0.7, 15.7]), or VScr of 10 to 14 microg/dL (0.9 [0.3, 3.0]). CScr and VScr in the 15 to 19 microg/dL range were associated with significantly higher odds of having VPb >/=20 microg/dL when compared with screening tests <10 microg/dL. CONCLUSIONS: These data indicate that special diagnostic testing within 90 days for children with CScr and VScr in the 10 to 14 microg/dL range does not result in greater identification of VPb >/=20. Raising the set point for diagnostic testing to 15 microg/dL in this sample would eliminate the unnecessary follow-up of 5162 children, of whom 3360 were falsely misclassified as having undue lead exposure.

Child, Preschool↗
PubMed1999

The association between state housing policy and lead poisoning in children.

OBJECTIVES: This study examined the effect of an active program of household lead paint hazard abatement, applied over 22 years, on childhood lead poisoning in Massachusetts. METHODS: A small areas analysis was used to compare screening blood lead levels of children in Worcester County, Mass (n = 27,590), with those in Providence County, RI (n = 19,071). Data were collapsed according to census tract. RESULTS: The percentage of children with lead poisoning (blood lead level > or = 20 micrograms/dL [Pe20]) was, on average, 3 times higher in Providence County census tracts (3.2% vs 0.9% in Worcester County census tracts, P < .0001), despite similar percentages of pre-1950s housing in both counties. The ratio of Pe20 in Providence vs Worcester County census tracts was 2.2 (95% confidence interval = 1.8, 2.7), after adjustment for differences in housing, sociodemographic, and screening characteristics. This estimate was robust to alternative regression methods and sensitivity analyses. CONCLUSIONS: Massachusetts policy, which requires lead paint abatement of children's homes and places liability for lead paint poisoning on property owners, may have substantially reduced childhood lead poisoning in that state.

Child↗
PubMed1998

Predictors of smoking cessation in adolescents.

OBJECTIVE: To examine factors associated with cessation of smoking in adolescents 12 to 18 years of age who smoke cigarettes. DESIGN AND SETTING: Prospective school-based cohort study of 1384 New Hampshire high school students surveyed at baseline and annually up to 3 subsequent years regarding their substance abuse behaviors, including adolescents who smoked 1 or more cigarettes within the past 30 days at baseline. OUTCOME MEASURES: Cessation behavior was defined by a subsequent response indicating nonsmoking status. We examined associations between smoking cessation and baseline measurements of the level of addiction (cigarette consumption pattern), experience with quitting, intent to quit now and in the future, opinion of adults smoking more than 1 pack of cigarettes per day, social influences to smoke, sex, and psychological attributes. RESULTS: Of 276 adolescents who qualified as cigarette smokers at baseline, 123 (44.6%) were occasional smokers, 65 (23.6%) were daily smokers of 1 to 9 cigarettes, and 88 (31.9%) were daily smokers of 10 or more cigarettes. While 39 (14.1%) had smoked for 1 year or less, 62 (22.5%) had smoked for 6 or more years. Seventy-five (27.2%) reported failed past attempts to quit smoking, 71 (25.7%) reported wanting to quit now, and 50 (18.1%) reported definitely intending to be a nonsmoker in the future. Seventy-nine smokers (28.6%) described themselves as nonsmokers in follow-up surveys. The smoking cessation rate was 46.3% among occasional smokers, 12.3% among daily smokers of 1 to 9 cigarettes, and 6.8% among daily smokers of 10 or more cigarettes. Smoking cessation was associated with occasional smoking status (adjusted odds ratio 6.67 compared with daily smokers of 10 or more cigarettes [95% confidence intervals, 2.26-19.69]), and definite intentions to quit in the future (2.67 [95% confidence intervals, 1.2-5.7]). Most of those with definite intentions to quit in the future were occasional smokers (92.0%). CONCLUSIONS: This study documents cessation of smoking in nearly one third of the adolescent smokers. The cessation rate among daily smokers of 10 or more cigarettes per day is comparable with adult cessation rates. Adolescents who are less addicted, measured by low frequency of cigarette use, are more likely than daily users to quit. In addition, definite intent to quit in the future predicts cessation, but only among occasional smokers. In contrast with adults, experience with quitting was not associated with a higher likelihood of cessation. Pediatricians should focus on keeping occasional smokers from moving into daily smoking status, where nicotine addiction begins to play a prominent role in maintaining the behavior. Further study is needed to guide enhancement of the recruitment of adolescents into cessation, assessment of nicotine dependence in daily adolescent smokers, and appropriate use of nicotine replacement therapy in this group.

Adolescent↗
PubMed1997

Cigarette promotional items in public schools.

OBJECTIVES: To assess the prevalence of ownership of cigarette promotional items (CPIs) by rural northern New England students and to examine the association between CPI ownership and smoking behavior. DESIGN AND SETTING: Voluntary, self-administered survey of 1265 sixth- through 12th-grade students representing 79% to 95% of all students attending 5 rural New Hampshire and Vermont public schools in October 1996. We examined the association between ownership of a CPI and smoking behavior through regression models and conducted a sensitivity analysis on the findings. MAIN OUTCOME MEASURES: Adjusted odds of being a smoker (lifetime use of > or = 100 cigarettes) and, among never smokers and experimental smokers, adjusted cumulative odds of having higher levels of smoking uptake given CPI ownership. RESULTS: One third of students owned a CPI. Prevalence of ownership did not vary by grade or sex, but was higher among poor-to-average school performers (45.0% vs 21.0% for excellent school performers, P < .001) and children whose friends and family members smoked (43.4% vs 13.8% for students with no family members or friends smoking, P < .001). Cigarette promotional items included articles of clothing (T-shirts, hats, backpacks, and jackets), smoking paraphernalia (lighters and ashtrays), camping gear, and electronics. More than half of CPIs (58.2%) bore the Marlboro logo, and almost one third (31.7%) bore the Camel logo. These items were obtained directly from catalogs or vendors 22.4% of the time. Whereas only 4.5% of students reported bringing a CPI to school with them the day of the survey, 44.5% reported seeing such an item at school the day of the survey. After controlling for confounding factors, such as having friends who smoke, students who owned CPIs were 4.1 times more likely to be smokers than those who did not own CPIs (95% confidence interval [CI], 3.1-5.5). Never and experimental smokers (n = 1008) who owned CPIs were more likely to be in a higher category on the smoking uptake index in grades 6 (cumulative odds ratio [OR = 5.7, 95% CI, 1.9-16.8), 7 (OR = 1.8, 95% CI, 0.9-3.7), 8 (OR = 2.3, 95% CI, 1.1-4.8), and 9 (OR = 2.1, 95% CI, 1.1-3.9), periods when children are most vulnerable to initiating cigarette use. A sensitivity analysis indicated that an unmeasured confounder of CPI ownership and smoking was unlikely to alter our conclusions. CONCLUSIONS: Cigarette promotional items are owned by one third of students in these rural northern New England schools. These items are highly visible in the public school setting, and their ownership is strongly associated with initiation and maintenance of smoking behavior. These data lend support to a ban on CPIs to be included in US Food and Drug Administration regulations to prevent tobacco use among US youth.

Adolescent↗
PubMed1997

Census tract analysis of lead exposure in Rhode Island children.

There has been increasing interest in a targeted approach to the screening and prevention of lead exposure in children. Targeted screening requires an understanding of variation in lead exposure in individual children or by region. In order to better understand variation by region, we studied Rhode Island lead poisoning screening data, examining average lead exposure to children living in 136 Providence County census tracts (CTs). The study population included 17,956 children aged 59 months and under, who were screened between May 1, 1992, and April 30, 1993. We evaluated the relationship between the percentage of children with blood lead > or = 10 micrograms/dL (pe10) and sociodemographic and housing characteristics, derived from United States 1990 Census data, of these CTs. CT descriptors included population density, percentage of households receiving public assistance income, median per capita income, percentage of households female headed, percentage of houses owner occupied, percentage of houses built before 1950, percentage of houses vacant, percentage of population Black, percentage of recent immigrants, and intraurban mobility. On average, 109 children were screened in each census tract; mean screening rate was 44%. There was wide variation in average lead exposure among census tracts, with pe10 ranging from 3 to 60% of screened children (mean 27%). Individual census variables explained between 24 and 67% of the variance in pe10 among CTs. A multiple regression model including percentage screened, percentage of households receiving public assistance, percentage of houses built before 1950, In (percentage of houses vacant), and percentage of recent immigrants explained 83% of variance in pe10. The percentage of houses built before 1950, a variable which models the presence of lead paint in old houses, displayed the largest adjusted effect on pe10 over the range observed for that variable in RI CTs. The percentage of houses vacant was also a highly significant and robust predictor; we suggest that vacancy is an ecological marker for the deterioration of leadbased paint, with higher vacancy neighborhoods containing houses in poorer condition. In Rhode Island, census tracts with high vacancy rates also have high rates of recent immigration, making immigrant groups vulnerable to lead exposure. Small-areas analysis may be useful in directing resources to high risk areas, explaining the sociocultural forces which produce such exposure and analyzing the effects of housing policy over time in states with high screening penetration.

Child, Preschool↗
PubMed1997

Calcium and phosphorus supplementation of iron-fortified infant formula: no effect on iron status of healthy full-term infants.

One objective of this clinical trial was to determine whether calcium and phosphorus supplementation of infant formula affects the iron status of healthy full-term infants. One hundred three infants were randomly assigned to receive iron-fortified, cow milk-based infant formula (465 mg Ca and 317 mg P/L) or the same formula with added calcium glycerophosphate (1800 mg Ca and 1390 mg P/L) for 9 mo. Reported calcium intake for supplemented infants was about four times that of control infants, ranging from a mean of 1741 mg/d at baseline to 1563 mg/d at 9 mo. There was no difference by treatment group in mean or median change from baseline of serum ferritin, total-iron-binding capacity, erythrocyte protoporphyrin, or hematocrit at 4 and 9 mo after enrollment. Incidence of iron deficiency was similar for both groups and no infant developed iron deficiency anemia during the trial. This study indicates that the well-documented inhibitory effect of calcium and phosphorus on iron absorption is not clinically important in infants fed iron-fortified infant formula.

Absorption↗
PubMed1996

Utility of a risk assessment questionnaire in identifying children with lead exposure.

OBJECTIVE: To evaluate the utility of the Centers for Disease Control and Prevention (CDC) Risk Questionnaire and a behavioral risk factor questionnaire in identifying children with blood lead concentrations of 0.48 mumol/L (10 micrograms/dL) or more. DESIGN: Cross-sectional study of 463 urban Massachusetts children (6 to 72 months of age) screened for lead with venous blood. RESULTS: Twenty-two percent of the children had elevated blood lead concentrations. Of the five CDC questions, only one was significantly associated with an increased adjusted odds ratio for elevated blood lead: having a sibling, housemate, or playmate who was followed up or treated for lead poisoning (odds ratio, 2.7; 95% confidence interval, 1.7 to 4.2; P < .001). Children who had at least one positive or equivocal response to any of the five CDC questions (n = 318 [68.7%]) were not at higher risk than were children who displayed a negative response to all five questions (odds ratio, 1.1; 95% confidence interval, 0.7 to 1.8; P = .69). Of nine behaviors surveyed, two were associated with an increased adjusted odds for elevated blood lead: use of a pacifier (odds ratio, 2.4; 95% confidence interval, 1.3 to 4.4; P = .01) and playing near the outside of the home (odds ratio, 3.4; 95% confidence interval, 2.0 to 5.8; P < .001). CONCLUSIONS: In this population of children, the CDC risk questionnaire did not identify a group at higher risk for lead exposure. We suggest that practitioners in urban communities screen all children according to the same schedule. We conclude that risk factors differ by community and no risk questionnaire developed at the national level should be applied across communities to target screening.

Centers for Disease Control and Prevention, U.S.↗
PubMed1996

Disparities in clinical laboratory performance for blood lead analysis.

OBJECTIVE: To evaluate the validity of blood lead analysis for clinical specimens. DESIGN: We submitted blood lead samples with a known lead concentration, in a blinded fashion, as clinical specimens to 18 laboratories. These laboratories were surveyed for the following characteristics that were hypothesized to be related to assay validity: laboratory ownership (state vs private), participation in the Centers for Disease Control Blood Lead Proficiency Program, assay method, and price. Each laboratory received 6 specimens with an actual blood lead (ABPb) concentration of 0.43 mumol/L (9 micrograms/dL) and 3 additional specimens--each with an ABPb concentration of 0.33, 0.89, and 1.59 mumol/L (6.9, 18.4, and 32.9 micrograms/dL, respectively). OUTCOME MEASURES: Misclassification error rates for reporting an elevation ( > or = 0.48 mumol/L [ > or = 10 micrograms/dL) in the blood lead concentration, the within-laboratory mean and coefficient of variation (CV) (for multiple specimens with an ABPb concentration of 0.43 mumol/L [9 micrograms/dL]), and the adjusted odds of a reported blood lead concentration differing from those of an ABPb concentration by more than 0.14 mumol/L (3 micrograms/dL). RESULTS: Blood lead results were obtained for 157 of 162 submissions. One laboratory reported all blood lead specimens as "below 0.48 mumol/L (10 micrograms/dL)." Two (11%) of 18 specimens with an ABPb concentration of 0.89 mumol/L (18.4 micrograms/dL) and 1 (6%) of 17 with an ABPb concentration of 1.59 mumol/L (32.9 micrograms/dL) were classified as below 0.48 mumol/L (10 micrograms/dL); 2 (11%) of 18 with an ABPb concentration of 0.33 mumol/L (6.9 micrograms/dL) and 44 (42%) of 104 with an ABPb concentration of 0.43 mumol/L (9 micrograms/dL) were classified as 0.48 mumol/L or greater ( > or = 10 micrograms/dL). For specimens with an ABPb concentration of 0.43 mumol/L (9 micrograms/dL), the within-laboratory mean ranged from 0.23 to 0.52 mumol/L (4.8-10.7 micrograms/dL); the CV ranged from 3% to 37%. Laboratories that used anodic stripping voltammetry were 6.3 (95% confidence interval, 1.4-28.6) times more likely to report a specimen that differed from the ABPb concentration by more than 0.14 mumol/L (3 micrograms/dL) than those that used atomic absorption methods. No other laboratory characteristic predicted discordance between the reported blood lead and ABPb concentrations. CONCLUSIONS: This study documents wide variation in the validity of the blood lead measurement among clinical laboratories. While the performance of some laboratories far exceeded the criteria of the Centers for Disease Control Blood Lead Proficiency Program, others made large errors that could have resulted in the false-negative misclassification of children with significant lead exposure. Given these differences, the purchasers of laboratory services may require access to laboratory proficiency data to make rational choices among clinical laboratories. Further study of laboratory performance on clinical specimens is required to determine if order-of-magnitude errors occur with sufficient frequency to warrant routine submission of blinded quality control specimens by proficiency programs and to determine the cause of the poor performance of laboratories that used the anodic stripping voltammetry methodology.

Clinical Laboratory Techniques↗
PubMed1996

Rethinking the threshold for an abnormal capillary blood lead screening test.

OBJECTIVES: To examine the test characteristics of the capillary blood lead screening test as a predictor of elevated venous blood lead levels, using receiver operating characteristic (ROC) curves. To consider a rational capillary blood lead cutoff value in the context of what has been learned about the screening test and what is understood about the clinical course of children with elevated blood lead levels in the mild range (0.48-0.92 mumol/L [10-19 micrograms/dL]). DESIGN: In a clinical trial, 513 urban children aged 6 years and younger were screened for lead exposure. Paired samples of venous blood were drawn from all children. For these children we examine the ROC curves for capillary blood lead levels as a predictor of elevated venous blood lead levels above 2 thresholds, 0.48 and 0.97 mumol/L (10 and 20 micrograms/dL). Contaminated capillary specimens were defined as those in which the capillary result exceeded the venous result by 0.12 mumol/L (2.5 micrograms/dL) or more (n = 49). MAIN OUTCOME MEASURES: Test sensitivity and false-positive rate (equal to 1-specificity) as a function of the capillary screening cutoff value. Area under the ROC curve as a measure of screening test performance. RESULTS: Venous blood lead levels were 0.48 mumol/L (10 micrograms/dL) or more in 20.5% and 0.97 mumol/l (20 micrograms/dL) or more in 2.3% of children. Measurement of capillary blood lead levels performed very well as a screening test with an area under the ROC curve of 0.97 at the 0.48 mumol/L (10-micrograms/dL) threshold and 0.99 at the 0.97-mumol/L (20-micrograms/dL) threshold. For a capillary cutoff value of 0.39 mumol/L (8 micrograms/dL) and an elevated blood lead level threshold of 0.48 mumol/L (10 micrograms/dL), test sensitivity is 100% and the false-positive rate is 23%. Test sensitivity drops to 91%, 63%, and 45% at capillary cutoff values of 0.48, 0.58, and 0.68 mumol/L (10, 12, and 14 micrograms/dL), respectively. The false-positive rate drops to 8%, 2%, and 1% at capillary cutoff values of 0.48, 0.58, and 0.68 mumol/L (10, 12, and 14 micrograms/dL), respectively. Changing the contamination rate by appending or deleting contaminated capillary specimens from the data set had little effect on the area under the ROC curve at either threshold. CONCLUSIONS: In this sample of children, capillary blood lead measurement performed well as a screening test for elevated venous blood lead levels. Altering the capillary specimen contamination rate has little effect on the rest characteristics because much of the misclassification error resulted from random analytic error in the analysis of blood lead levels, which is high compared with the threshold of concern (0.48 mumol/L [10 micrograms/dL]). Because of lack of data on clinical outcomes for children with elevated blood lead levels in the 0.48- to 0.92-mumol/L (10- to 19-micrograms/dL) range, we suggest that the greatest utility be placed on avoiding false-positive misclassification. A clinical capillary screening cutoff value of 0.72 mumol/L (15 micrograms/dL) would avoid most false-positive results and would permit 100% sensitivity in detecting children with blood lead levels of 0.97 mumol/L (20 micrograms/dL) or higher.

Blood Chemical Analysis↗
PubMed1996

Iron deficiency in Massachusetts communities: Socioeconomic and demographic risk factors among children.

OBJECTIVES: This study examined the association between community rates of iron deficiency in children and sociodemographic characteristics of Massachusetts communities. METHODS: Between April 1990 and March 1991, 238 273 Mssachusetts children 6 through 59 months of age were screened; iron deficiency was defined as an erythrocyte protopophyrin concentration of 0.62 micromol/L or higher and a blood lead level of less than 1.2 micromol/L. Sociodemographic data were obtained from the 1990 US Census. RESULTS: Five percent of communities had iron deficiency rates greater than 13.9 per 100 children screened. Iron deficiency rate was positively associated with proportion of Southeast Asians (odds ratio [OR] = 1.10, 95% confidence interval [CI] = 1.08, 1.12), proportion of Hispanics (OR = 1.008, 95% CI = 1.002, 1.013), and high school incompletion (OR = 1.028, 95% CI = 1.020, 1.035). Similarly, an examination of three Massachusetts cities indicated that the iron deficiency rate was higher for children with Southeast Asian (relative risk [RR] = 3.6, 95% CI = 3.3, 3.8) and Hispanic (RR = 1.6, 95% CI = 1.5, 1.8) surnames than for all other children. CONCLUSIONS: Wide variation exists in iron deficiency rates for children in Massachusetts communities. Community iron deficiency was associated with low socioeconomic status and high proportions of Southeast Asians and Hispanics.

Anemia, Iron-Deficiency↗
PubMed1995

Childhood lead poisoning in Massachusetts communities: its association with sociodemographic and housing characteristics.

OBJECTIVES: The purpose of the study was to examine the relationship between communities' sociodemographic and housing characteristics and incidence of lead poisoning. METHODS: This was a population-based correlational study of 238,275 Massachusetts children from birth through 4 years of age who were screened for lead poisoning in 1991-1992. A logistic regression model was developed with the community as the unit of analysis, the case identification rate for lead poisoning (newly identified children with venous blood lead > or = 25 micrograms/dL per 1000 children) as the dependent variable, and US census variables as independent variables. RESULTS: A significant independent relationship with the community case identification rate of lead poisoning was found for seven variables: median per capita income, percentage of housing built before 1950, percentage of the population who were Black, percentage of children screened, and a "poverty index." Rates of iron deficiency and percentage of Hispanics were not associated with the case identification rate of lead poisoning. CONCLUSIONS: Massachusetts communities' incidence of lead poisoning is correlated with sociodemographic and housing characteristics. In states similar to Massachusetts and without screening data, this model may help target screening programs.

Black or African American↗
PubMed1994

Obesity and stature in adolescence and earnings in young adulthood. Analysis of a British birth cohort.

OBJECTIVE: To examine the association between obesity and stature at various ages and earnings in young men and women at age 23 years. DESIGN: We estimated the effect of obesity on earnings by constructing a series of ordinary least-squares regression equations in which the dependent variable was the natural logarithm of hourly earnings at age 23 years. We report the coefficients for obese subjects compared with those for the nonobese subjects and for height while controlling for a number of other factors that are known to affect pay. SETTING: A birth cohort of 12,537 respondents at age 23 years from the National Child Development Study, which consists of all children born in England, Scotland, and Wales between March 3 and 9, 1958. OUTCOME MEASURE: Hourly earnings at age 23 years as it relates to obesity, as determined by the body mass index and stature measured as a continuous variable. RESULTS: Men and women who had been obese at age 16 years had significantly fewer years of schooling than did their nonobese peers. Obese women performed poorly on math and reading tests at ages 7, 11, and 16 years when compared with their nonobese peers. Regression analyses indicated no relationship between obesity at any age and earnings at age 23 years in males. In contrast, there was a statistically significant inverse relation between obesity and earnings in females, independent of parental social class and ability test scores of the child. Female adolescents who were in the top 10% of the body mass index at age 16 years earned 7.4% less (95% confidence interval, -11% to -3.8%) than their nonobese peers; those in the top 1% earned 11.4% less (-21% to -1.5%). The inverse relationship between obesity at 16 years of age and earnings persisted whether the adolescent female remained obese (-6.4% [-12.3% to -4.7%]) or moved into the nonobese category by age 23 years (-7.5% [-12.5% to -2.4%]). A positive relationship was found between height at age 16 years and earnings at age 23 years for men (but not for women) after controlling for social class and IQ. CONCLUSIONS: This study demonstrates an inverse relationship between obesity at 16 years and earnings at age 23 years for British women; the magnitude of the relation is similar to that of other factors that predict earnings, such as gender, job training, and union membership. In the case of men, we found a positive relationship between height and subsequent earnings but no obesity effects.

Adolescent↗
PubMed1994

Poisoned landscapes: the epidemiology of environmental lead exposure in Massachusetts children 1990-1991.

This research models the geographic variation in lead poisoning among children living in Massachusetts between 1990 and 1991. Elevated levels of blood lead, which reduce educational performance, arise because children are exposed to unnaturally concentrated sources of lead in the built environment. A Poisson regression model indicates that a large number of children with lead poisoning may be detected in towns with a high proportion of older housing, female headed households, African-Americans, and an industrial heritage. Our results suggest links between the processes of urbanization and industrialization in Massachusetts and today's lead poisoned landscapes.

Child, Preschool↗