Jan Blustein

Infant antibiotic exposures and early-life body mass

Objectives:To examine the associations of antibiotic exposures during the first 2 years of life and the development of body mass over the first 7 years of life.Design:Longitudinal birth cohort study.Subjects:A total of 11 532 children born at ⩾2500 g in the Avon Longitudinal Study of Parents and Children (ALSPAC), a population-based study of children born in Avon, UK in 1991–1992.Measurements:Exposures to antibiotics during three different early-life time windows (<6 months, 6–14 months, 15–23 months), and indices of body mass at five time points (6 weeks, 10 months, 20 months, 38 months and 7 years).Results:Antibiotic exposure during the earliest time window (<6 months) was consistently associated with increased body mass (+0.105 and +0.083 s.d. unit, increase in weight-for-length Z-scores at 10 and 20 months, P<0.001 and P=0.001, respectively; body mass index (BMI) Z-score at 38 months +0.067 s.d. units, P=0.009; overweight OR 1.22 at 38 months, P=0.029) in multivariable, mixed-effect models controlling for known social and behavioral obesity risk factors. Exposure from 6 to 14 months showed no association with body mass, while exposure from 15 to 23 months was significantly associated with increased BMI Z-score at 7 years (+0.049 s.d. units, P=0.050). Exposures to non-antibiotic medications were not associated with body mass.Conclusions:Exposure to antibiotics during the first 6 months of life is associated with consistent increases in body mass from 10 to 38 months. Exposures later in infancy (6–14 months, 15–23 months) are not consistently associated with increased body mass. Although effects of early exposures are modest at the individual level, they could have substantial consequences for population health. Given the prevalence of antibiotic exposures in infants, and in light of the growing concerns about childhood obesity, further studies are needed to isolate effects and define life-course implications for body mass and cardiovascular risks.

Medicare Coverage, Supplemental Insurance, and the Use of Mammography by Older Women

BACKGROUND On January 1, 1991, the Medicare program began offering reimbursement for screening mammography every two years. This study examined the use of mammography in women covered by Medicare during the first two years that the screening benefit was offered. METHODS Medicare bills for 1991 and 1992 from a nationally representative sample of 4110 women 65 years of age or older were examined to determine the degree of compliance with recognized guidelines for screening mammography and the extent to which the use of mammography was associated with having supplemental insurance, which shields patients from the out-of-pocket costs associated with using Medicare benefits. RESULTS A total of 36.9 percent of older U.S. women had mammography during the first two years of the Medicare benefit for screening mammography. Only 14.4 percent of the women lacking supplemental insurance had mammography, as compared with 44.7 percent of those with employer-sponsored supplemental insurance, 40.1 percent of those with self-purchased supplemental insurance, and 23.9 percent of those with Medicaid supplemental insurance. These differences persisted in the stratified and multivariate analyses. As compared with women lacking supplemental insurance, women with employment-based supplemental insurance were more likely to undergo mammography (adjusted odds ratio, 3.03; 95 percent confidence interval, 2.17 to 4.23), as were women with self-purchased supplemental insurance (adjusted odds ratio, 2.97; 95 percent confidence interval, 2.13 to 4.15) and women with Medicaid supplemental insurance (adjusted odds ratio, 1.99; 95 percent confidence interval, 1.30 to 3.07). CONCLUSIONS The use of mammography was substantially below recommended levels during the first two years of Medicare coverage for screening mammography. Women lacking supplemental health insurance were at particularly high risk of failing to undergo mammography. Requiring copayments for preventive services is an obstacle to the effective mass screening of older women for breast cancer.

Faithful patients: the effect of long-term physician-patient relationships on the costs and use of health care by older Americans.

OBJECTIVES This study examined the impact of duration of physician-patient ties on the processes and costs of medical care. METHODS The analyses used a nationally representative sample of Americans 65 years old or older who participated in the Medicare Current Beneficiary Survey in 1991 and had a usual source of care. RESULTS Older Americans have long-standing ties with their physicians; among those with a usual source of care, 35.8% had ties enduring 10 years or more. Longer ties were associated with a decreased likelihood of hospitalization and lower costs. Compared with patients with a tie of 1 year or less, patients with ties of 10 years or more incurred

The role of diabetes mellitus in the higher prevalence of tuberculosis among Hispanics.

316.78 less in Part B Medicare costs, after adjustment for key demographic and health characteristics. However, substantial impacts on the use of selected preventive care services and the adoption of certain healthy behaviors were not observed. CONCLUSIONS This preliminary study suggests that long-standing physician-patient ties foster less expensive, less intensive medical care. Further studies are needed to confirm these findings and to understand how duration of tie influences the processes and outcomes of care.

Association of caesarean delivery with child adiposity from age 6 weeks to 15 years

OBJECTIVES This research studied the relative contribution of diabetes mellitus to the increased prevalence of tuberculosis in Hispanics. METHODS A case-control study was conducted involving all 5290 discharges from civilian hospitals in California during 1991 who had a diagnosis of tuberculosis, and 37,366 control subjects who had a primary discharge diagnosis of deep venous thrombosis, pulmonary embolism, or acute appendicitis. Risk of tuberculosis was estimated as the odds ratio (OR) across race/ethnicity, with adjustment for other factors. RESULTS Diabetes mellitus was found to be an independent risk factor for tuberculosis. The association of diabetes and tuberculosis was higher among Hispanics (adjusted OR [ORadj] = 2.95: 95% confidence interval [CI] = 2.61, 3.33) than among non-Hispanic Whites (ORadj = 1.31: 95% CI = 1.19. 1.45): among non-Hispanic Blacks, diabetes was not found to be associated with tuberculosis (ORadj = 0.93: 95% CI = 0.78, 1.09). Among Hispanics aged 25 to 54, the estimated risk of tuberculosis attributable to diabetes (25.2%) was equivalent to that attributable to HIV infection (25.5%). CONCLUSIONS Diabetes mellitus remains a significant risk factor for tuberculosis in the United States. The association is especially notable in middle-aged Hispanics.

High-technology cardiac procedures : the impact of service availability on service use in New York State

Objectives:To assess associations of caesarean section with body mass from birth through adolescence.Design:Longitudinal birth cohort study, following subjects up to 15 years of age.Setting and participants:Children born in 1991–1992 in Avon, UK who participated in the Avon Longitudinal Study of Parents and Children (ALSPAC) (n=10 219).Outcome measures:Primary outcome: standardized measures of body mass (weight-for length z-scores at 6 weeks, 10 and 20 months; and body mass index (BMI) z-scores at 38 months, 7, 9, 11 and 15 years). Secondary outcome: categorical overweight or obese (BMI ⩾85th percentile) for age and gender, at 38 months, 7, 9, 11 and 15 years.Results:Of the 10 219 children, 926 (9.06%) were delivered by caesarean section. Those born by caesarean had lower-birth weights than those born vaginally (−46.1 g, 95% confidence interval(CI): 14.6–77.6 g; P=0.004). In mixed multivariable models adjusting for birth weight, gender, parental body mass, family sociodemographics, gestational factors and infant feeding patterns, caesarean delivery was consistently associated with increased adiposity, starting at 6 weeks (+0.11 s.d. units, 95% CI: 0.03–0.18; P=0.005), through age 15 (BMI z-score increment+0.10 s.d. units, 95% CI: 0.001–0.198; P=0.042). By age 11 caesarean-delivered children had 1.83 times the odds of overweight or obesity (95% CI: 1.24–2.70; P=0.002). When the sample was stratified by maternal pre-pregnancy weight, the association among children born of overweight/obese mothers was strong and long-lasting. In contrast, evidence of an association among children born of normal-weight mothers was weak.Conclusion:Caesarean delivery is associated with increased body mass in childhood and adolescence. Research is needed to further characterize the association in children of normal weight women. Additional work is also needed to understand the mechanism underlying the association, which may involve relatively enduring changes in the intestinal microbiome.

Race/ethnicity-Specific Associations of Urinary Phthalates with Childhood Body Mass in a Nationally Representative Sample

OBJECTIVE To study the impact of the in-hospital availability of three cardiac procedures (cardiac catheterization, bypass surgery, and angioplasty) on their use in patients during the period following acute myocardial infarction (AMI). DESIGN Retrospective cohort study, based on a statewide hospital discharge abstract data set. PARTICIPANTS Patients admitted with a principal diagnosis of AMI to New York State hospitals during March through June of 1986. MAIN OUTCOME MEASURES The odds of utilizing each of the three services either during the initial admission for AMI or during the 6-month postdischarge interval. Odds ratios (ORs) were calculated comparing utilization in three groups of patients: those initially presenting to hospitals lacking all three services, those initially presenting to hospitals offering only cardiac catheterization, and those initially presenting to hospitals offering all three of the cardiac services. Odds were adjusted for age, sex, race, income, primary payer, severity of illness, and geographical distance to hospital. RESULTS Relative to patients initially presenting to hospitals lacking all three services, patients initially presenting to hospitals offering only cardiac catheterization were more likely to undergo cardiac catheterization (OR, 3.57; 95% confidence interval [Cl], 3.03 to 4.22), but were not significantly more likely to undergo bypass surgery or angioplasty. Relative to patients initially presenting to hospitals lacking all three services, patients initially presenting to hospitals offering all three services were more likely to undergo cardiac catheterization (OR, 5.50; 95% Cl, 4.66 to 6.50), bypass surgery (OR, 2.52; 95% Cl, 1.95 to 3.24), and angioplasty (OR, 6.85; 95% Cl, 4.73 to 10.58). CONCLUSIONS The availability of cardiac services in the hospital to which patients initially present strongly influences the likelihood of their use in the period following AMI.

The Use of Mammography by Women Aged 75 and Older: Factors Related to Health, Functioning, and Age

Background: Phthalates have antiandrogenic effects and may disrupt lipid and carbohydrate metabolism. Racial/ethnic subpopulations have been documented to have varying urinary phthalate concentrations and prevalences of childhood obesity. Objective: We examined associations between urinary phthalate metabolites and body mass outcomes in a nationally representative sample of U.S. children and adolescents. Methods: We performed stratified and whole-sample cross-sectional analyses of 2,884 children 6–19 years of age who participated in the 2003–2008 National Health and Nutrition Examination Survey. Multivariable linear and logistic analyses of body mass index z-score, overweight, and obesity were performed against molar concentrations of low-molecular-weight (LMW), high-molecular-weight (HMW), and di-2-ethylhexylphthalate (DEHP) metabolites, controlling for sex, television watching, caregiver education, caloric intake, poverty–income ratio, race/ethnicity, serum cotinine, and age group. We used sensitivity analysis to examine robustness of results to removing sample weighting, normalizing phthalate concentrations for molecular weight, and examining different dietary intake covariates. Results: In stratified, multivariable models, each log unit (roughly 3-fold) increase in LMW metabolites was associated with 21% and 22% increases in odds (95% CI: 1.05–1.39 and 1.07–1.39, respectively) of overweight and obesity, and a 0.090-SD unit increase in BMI z-score (95% CI: 0.003–0.18), among non-Hispanic blacks. Significant associations were not identified in any other racial/ethnic subgroup or in the study sample as a whole after controlling for potential confounders, associations were not significant for HMW or DEHP metabolites, and results did not change substantially with sensitivity analysis. Conclusions: We identified a race/ethnicity–specific association of phthalates with childhood obesity in a nationally representative sample. Further study is needed to corroborate the association and evaluate genetic/epigenomic predisposition and/or increased phthalate exposure as possible explanations for differences among racial/ethnic subgroups.

Urinary Phthalates and Increased Insulin Resistance in Adolescents

BACKGROUND AND OBJECTIVES: Mammographic screening for breast cancer is of uncertain clinical benefit for women 75 years of age and older. Some have argued against instituting routine screening in this age group, noting that disability and shorter life expectancy may diminish the desirability and cost‐effectiveness of screening. We sought to determine the extent to which health, functioning, and age influence mammography use in this cohort.

Medicare’s Flagship Test Of Pay-For-Performance Did Not Spur More Rapid Quality Improvement Among Low-Performing Hospitals

BACKGROUND Di-2-ethylhexylphthalate (DEHP) is an environmental chemical commonly found in processed foods. Phthalate exposures, in particular to DEHP, have been associated with insulin resistance in adults, but have not been studied in adolescents. METHODS: Using cross-sectional data from 766 fasting 12- to 19-year-olds in the 2003–2008 NHANES, we examined associations of phthalate metabolites with continuous and categorical measures of homeostatic model assessment of insulin resistance (HOMA-IR). RESULTS: Controlling for demographic and behavioral factors, diet, continuous age, BMI category, and urinary creatinine, for each log (roughly threefold) increase in DEHP metabolites, a 0.27 increase (95% confidence interval 0.14–0.40; P < .001) in HOMA-IR was identified. Compared with the first tertile of DEHP metabolite in the study population (14.5% insulin resistant), the third tertile had 21.6% prevalence (95% confidence interval 17.2%–26.0%; P = .02). Associations persisted despite controlling for bisphenol A, another endocrine-disrupting chemical commonly found in foods, and HOMA-IR and insulin resistance were not significantly associated with metabolites of lower molecular weight phthalates commonly found in cosmetics and other personal care products. CONCLUSIONS: Urinary DEHP concentrations were associated with increased insulin resistance in this cross-sectional study of adolescents. This study cannot rule out the possibility that insulin-resistant children ingest food with higher phthalate content, or that insulin-resistant children excrete more DEHP.