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Calls by Lilienfeld, Fraser, and others some three decades ago to introduce epidemiology into undergraduate college education remain largely unfulfilled. Consideration of epidemiology as a "liberal art" has also led to exploring possibilities for introducing epidemiology into early education: to high and even middle schools. Adding epidemiology to school curricula should help educate the public to understand science-based evidence concerning the causes and treatments of disease, help inoculate them against a tsunami of biased and fraudulent media messaging, and permit advancing postgraduate education in epidemiology to even higher levels of scholarship., (Copyright © 2014 Elsevier Inc. All rights reserved.)

On June 20, 2013, the American Journal of Epidemiology sponsored a symposium at the Society for Epidemiologic Research's 46th Annual Meeting in Boston, Massachusetts, entitled, "What Is the Role of Epidemiology in the Era of Molecular Biology and Genomics?" The future of epidemiology depends on innovation in generating interesting and important testable hypotheses that are relevant to population health. These new strategies will depend on new technology, both in measurement of agents and environment and in the fields of pathophysiology and outcomes, such as cellular epidemiology and molecular pathology. The populations to be studied, sample sizes, and study designs should be selected based on the hypotheses to be tested and include case-control, cohort, and clinical trials. Developing large mega cohorts without attention to specific hypotheses is inefficient, will fail to address many associations with high-quality data, and may well produce spurious results.

This study estimates the effect of maternal infections during pregnancy on childhood asthma. One-thousand four-hundred and twenty-eight pregnant women were prospectively followed using structured interviews and chart review until their child’s 6th year of life. Infections were identified from outpatient and hospital visits. Childhood asthma was defined as physician diagnosis with symptoms at age six. Adjusted odds ratios were calculated from multivariable logistic regression models. Six-hundred and thirty-five women experienced an infection during pregnancy. Among antepartum infections, maternal urinary tract infections were significantly associated with childhood asthma (aOR 1.60, 95 % CI 1.12–2.29). Chorioamnionitis and maternal group beta streptococcus colonization were not significantly associated with an increased risk in childhood asthma. This study found an increased risk of asthma in children of women diagnosed with urinary tract infections during pregnancy, while other maternal infections did not increase the risk. [ABSTRACT FROM AUTHOR]

Manolio et al. (Am J Epidemiol. 2012;175:859–866) proposed that large cohort studies adopt novel models using “temporary assessment centers” to enroll up to a million participants to answer research questions about rare diseases and “harmonize” clinical endpoints collected from administrative records. Extreme selection bias, we are told, will not harm internal validity, and “process expertise to maximize efficiency of high-throughput operations is as important as scientific rigor” (p. 861). In this article, we describe serious deficiencies in this model as applied to the United States. Key points include: 1) the need for more, not less, specification of disease endpoints; 2) the limited utility of data collected from existing administrative and clinical databases; and 3) the value of university-based centers in providing scientific expertise and achieving high recruitment and retention rates through community and healthcare provider engagement. Careful definition of sampling frames and high response rates are crucial to avoid bias and ensure inclusion of important subpopulations, especially the medically underserved. Prospective hypotheses are essential to refine study design, determine sample size, develop pertinent data collection protocols, and achieve alliances with participants and communities. It is premature to reject the strengths of large national cohort studies in favor of a new model for which evidence of efficiency is insufficient. [ABSTRACT FROM PUBLISHER]

Many studies have reported that antibiotic use may be associated with increased risk of childhood asthma. Respiratory tract infections in small children may be difficult to distinguish from early symptoms of asthma, and studies may have been confounded by “protopathic” bias, where antibiotics are used to treat early symptoms of asthma. These analyses of a cohort including 1,401 US children assess the association between antibiotic use within the first 6 months of life and asthma and allergy at 6 years of age between 2003 and 2007. Antibiotic exposure was associated with increased risk of asthma (adjusted odds ratio = 1.52, 95% confidence interval (CI): 1.07, 2.16). The odds ratio if asthma was first diagnosed after 3 years of age was 1.66 (95% CI: 0.99, 2.79) and, in children with no history of lower respiratory infection in the first year of life, the odds ratio was 1.66 (95% CI: 1.12, 3.46). The adverse effect of antibiotics was particularly strong in children with no family history of asthma (odds ratio = 1.89, 95% CI: 1.00, 3.58) (Pinteraction = 0.03). The odds ratio for a positive allergy blood or skin test was 1.59 (95% CI: 1.10, 2.28). The results show that early antibiotic use was associated with asthma and allergy at 6 years of age, and that protopathic bias was unlikely to account for the main findings. [ABSTRACT FROM PUBLISHER]

There is growing concern among epidemiologists that most discovered associations are either inflated or false. The reasons for this concern have focused on methodological issues in the conduct and publication of epidemiologic research. This commentary suggests that another reason for discrepant findings may be that animal research is producing implausible hypotheses. Many animal studies are methodologically weak, and the animal literature is not systematically reviewed and synthesized. Moreover, most bodies of animal literature may be so heterogeneous that they can be used selectively to support the plausibility of almost any epidemiology study result. Epidemiologists themselves also do not consistently conduct systematic reviews of bodies of biological evidence which might point to sources of bias in an evidence base. Animal research will likely continue to provide the biological basis for epidemiological investigation, but substantial improvement is needed in how it is conducted and synthesized to improve the predictability of animal studies for the human condition. [Copyright &y& Elsevier]

Modern microarray genotyping now permits simultaneous analysis of tens of thousands of polymorphisms, and this technology is being widely used to associate the role of genes with the etiology of complex disease. Genome-wide hypothesis-free mapping will also increasingly generate candidate genes that require further testing in association studies. At the same time, genetic effects are increasingly observed to be buffered by a wide array of biologic mechanisms that evolved to protect the genome from environmental insult and that serve to obscure observation of direct effects of polymorphisms on a disease phenotype. These two forces combine to make replication of genomic epidemiology extraordinarily difficult. Traditional research synthesis of emerging bodies of genomic epidemiology is problematic and often quickly outdated. The author proposes that electronic evidence-based methodology, perhaps modeled after that used by the Cochrane Collaboration in clinical medicine, would facilitate the systematic preparation and frequent updating of systematic reviews, which is essential for identifying valid and replicable gene-disease associations. [ABSTRACT FROM AUTHOR]

Few studies of preeclampsia have assessed physical activity level, yet recent evidence suggests that the pathologic mechanisms in preeclampsia are similar to those in cardiovascular disease, for which physical activity is shown to be protective. The authors assessed the independent and combined effects of work and regular leisure-time physical activity (LTPA) during early pregnancy on risk of de novo preeclampsia (n = 44) and gestational hypertension (n = 172) among women recruited from 13 obstetric practices in the New Haven, Connecticut, area between 1988 and 1991. Control subjects were normotensive throughout pregnancy (n = 2,422). Information on time at work spent sitting, standing, and walking and on LTPA before and during pregnancy was collected via face-to-face interviews. Logistic regression analyses suggested that women who engaged in any regular LTPA regardless of caloric expenditure (adjusted odds ratio (aOR) = 0.66, 95% confidence interval (CI): 0.35, 1.22), were unemployed (aOR = 0.64, 95% CI: 0.21, 2.00), or had nonsedentary jobs (aOR = 0.71, 95% CI: 0.37, 1.36) were at decreased risk of preeclampsia. Analyses of gestational hypertension showed no indication of a protective effect of workplace activity, LTPA, or unemployment. Consistent with other studies, these data suggest that regular physical activity during pregnancy may reduce preeclampsia risk. [ABSTRACT FROM AUTHOR]

The relationship between abortion experience and contraceptive practice is examined among women having a first or repeat induced abortion at the same clinic(n=443 in each group). A previous abortion was the single most important predictor of past contraceptive practices and of contraception at the conception of the pregnancy being terminated. A previous abortion was associated with greater use of all methods of contraception among women not on welfare (P < 0·001). During the 18–month study the proportion of patients who had had previous abortions rose from 13·3% to 21·1%, and those undergoing repeat abortions appeared increasingly likely to be on welfare. Contraceptive practies did not change over time except for women on welfare having repeat abortions who became less likely to have used contraception at the time of conception (p < 0·05). While the experience of abortion is generally associated with improved contraceptive practice, many women in this population, particularly those on welfare, appear to remain exposed to unprotected coitus and subsequent repeat abortion. [ABSTRACT FROM PUBLISHER]

CONTEXT: The increasing prevalence of childhood asthma has been associated with low microbial exposure as described by the hygiene hypothesis. OBJECTIVE: We sought to evaluate the evidence of association between antibiotic exposure during pregnancy or in the first year of life and risk of childhood asthma. METHODS: PubMed was systematically searched for studies published between 1950 and July 1, 2010. Those that assessed associations between antibiotic exposure during pregnancy or in the first year of life and asthma at ages 0 to 18 years (for pregnancy exposures) or ages 3 to 18 years (for first-year-of-life exposures) were included. Validity was assessed according to study design, age at asthma diagnosis, adjustment for respiratory infections, and consultation rates. RESULTS: For exposure in the first year of life, the pooled odds ratio (OR) for all studies (N = 20) was 1.52 (95% confidence interval [CI]: 1.30-1.77). Retrospective studies had the highest pooled risk estimate for asthma (OR: 2.04 [95% CI: 1.83-2.27]; n = 8) compared with database and prospective studies (OR: 1.25 [95% CI: 1.08-1.45]; n = 12). Risk estimates for studies that adjusted for respiratory infections (pooled OR: 1.16 [95% CI: 1.08-1.25]; n = 5) or later asthma onset (pooled OR for asthma at or after 2 years: OR: 1.16 [95% CI: 1.06-1.25]; n = 3) were weaker but remained significant. For exposure during pregnancy (n = 3 studies), the pooled OR was 1.24 (95% CI: 1.02-1.50). CONCLUSIONS: Antibiotics seem to slightly increase the risk of childhood asthma. Reverse causality and protopathic bias seem to be possible confounders for this relationship. [ABSTRACT FROM AUTHOR]

PURPOSE: Asthma is a major complication of pregnancy, but there are currently no reliable national estimates for the United States of asthma prevalence in pregnancy or in the childbearing years.METHODS: The prevalence of asthma among pregnant women and all childbearing-aged women was estimated and examined by age group using the National Health Interview Survey (NHIS), 1997–2000, the Behavioral Risk Factor Surveillance System (BRFSS), 2000–2001, and the Third National Health and Nutrition Examination Survey (NHANES III), 1988–1994. Time trends were explored using NHANES II (1976–1980) and NHANES III (1988–1994).RESULTS: Asthma was estimated to affect from 88,573 to 190,650 pregnant women between 1997 and 2001, or approximately 3.7% to 8.4% of pregnant women in the United States. A slightly lower estimate of 3.2% was obtained for the period between 1988 and 1994. Among adult women of childbearing age, a two-fold increase in asthma from 2.9% to 5.8% occurred between 1976–1980 and 1988–1994. Among women aged 18 to 24, the increase was three-fold, from 1.8% to 6.0%.CONCLUSION: The prevalence of asthma during pregnancy may be higher than previously estimated and appears to be continuing to increase. [Copyright &y& Elsevier]