Search

Cancer is an important cause of childhood mortality, yet the etiology is largely unknown. A combination of pre- and postnatal factors is thought to be implicated, including maternal medication use. We aimed to provide: 1) a systematic review of peer-reviewed publications on associations between maternal medication use and childhood cancer, with a focus on study design and methodology; and 2) suggestions for how to increase transparency, limit potential biases, and improve comparability in studies on maternal medication use and childhood cancer. We conducted a systematic search in the PubMed, Embase, Scopus, Cochrane, and Web of Science databases to June 8, 2020. Altogether, 112 studies were identified. The reviewed studies were heterogeneous in study design, exposure, and outcome classification. In 21 studies (19%), the outcome was any childhood cancer. Of the 91 papers that reported on specific types of cancer, 62% did not report the cancer classification system. The most frequently investigated medication groups were sex hormones (46 studies, excluding fertility medications), and antiinfectives (37 studies). Suggestions for strengthening future pharmacoepidemiologic studies on maternal medication use and childhood cancer relate to choice of cancer classification system, exposure windows, and methods for identification of, and control for, potential confounders. [ABSTRACT FROM AUTHOR]

Ozone is associated with adverse health; however, less is known about vulnerable/sensitive populations, which we refer to as sensitive populations. We systematically reviewed epidemiologic evidence (1988-2013) regarding sensitivity to mortality or hospital admission from short-term ozone exposure. We performed meta-analysis for overall associations by age and sex; assessed publication bias; and qualitatively assessed sensitivity to socioeconomic indicators, race/ethnicity, and air conditioning. The search identified 2,091 unique papers, with 167 meeting inclusion criteria (73 on mortality and 96 on hospitalizations and emergency department visits, including 2 examining both mortality and hospitalizations). The strongest evidence for ozone sensitivity was forage. Per 10-parts per billion increase in daily 8-hour ozone concentration, mortality risk for younger persons, at 0.60% (95% confidence interval (Cl): 0.40, 0.80), was statistically lower than that for older persons, at 1.27% (95% Cl: 0.76,1.78). Findings adjusted for publication bias were similar. Limited/suggestive evidence was found for higher associations among women; mortality risks were 0.39% (95% Cl: -0.22,1.00) higher than those for men. We identified strong evidence for higher associations with unemployment or lower occupational status and weak evidence of sensitivity for racial/ethnic minorities and persons with low education, in poverty, or without central air conditioning. Findings show that some populations, especially the elderly, are particularly sensitive to short-term ozone exposure. [ABSTRACT FROM AUTHOR]

Metal exposure has been suggested as a possible environmental risk factor for Parkinson disease (PD). We searched the PubMed, EMBASE, and Cochrane databases to systematically review the literature on the relationship between metal exposure and PD risk and to examine the overall quality of each study and the exposure assessment method. A total of 83 case-control studies and 5 cohort studies published during the period 1963–July 2021 were included, of which 73 were graded as being of low or moderate overall quality. Investigators in 69 studies adopted self-reported exposure and biomonitoring after disease diagnosis for exposure assessment approaches. The meta-analyses showed that concentrations of copper and iron in serum and concentrations of zinc in either serum or plasma were lower, while concentrations of magnesium in CSF and zinc in hair were higher, among PD cases as compared with controls. Cumulative lead levels in bone were found to be associated with increased risk of PD. We did not find associations between other metals and PD. The current level of evidence for associations between metals and PD risk is limited, as biases from methodological limitations cannot be ruled out. High-quality studies assessing metal levels before disease onset are needed to improve our understanding of the role of metals in the etiology of PD. [ABSTRACT FROM AUTHOR]

Despite repeated calls by scholars to critically engage with the concepts of race and ethnicity in US epidemiologic research, the incorporation of these social constructs in scholarship may be suboptimal. This study characterizes the conceptualization, operationalization, and utilization of race and ethnicity in US research published in leading journals whose publications shape discourse and norms around race, ethnicity, and health within the field of epidemiology. We systematically reviewed randomly selected articles from prominent epidemiology journals across 5 periods: 1995–1999, 2000–2004, 2005–2009, 2010–2014, and 2015–2018. All original human-subjects research conducted in the United States was eligible for review. Information on definitions, measurement, coding, and use in analysis was extracted. We reviewed 1,050 articles, including 414 (39%) in our analyses. Four studies explicitly defined race and/or ethnicity. Authors rarely made clear delineations between race and ethnicity, often adopting an ethnoracial construct. In the majority of studies across time periods, authors did not state how race and/or ethnicity was measured. Top coding schemes included "Black, White" (race), "Hispanic, non-Hispanic" (ethnicity), and "Black, White, Hispanic" (ethnoracial). Most often, race and ethnicity were deemed "not of interest" in analyses (e.g. control variables). Broadly, disciplinary practices have remained largely the same between 1995 and 2018 and are in need of improvement. [ABSTRACT FROM AUTHOR]

Wastewater surveillance for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been shown to be a valuable source of information regarding SARS-CoV-2 transmission and coronavirus disease 2019 (COVID-19) cases. Although the method has been used for several decades to track other infectious diseases, there has not been a comprehensive review outlining all of the pathogens that have been surveilled through wastewater. Herein we identify the infectious diseases that have been previously studied via wastewater surveillance prior to the COVID-19 pandemic. Infectious diseases and pathogens were identified in 100 studies of wastewater surveillance across 38 countries, as were themes of how wastewater surveillance and other measures of disease transmission were linked. Twenty-five separate pathogen families were identified in the included studies, with the majority of studies examining pathogens from the family Picornaviridae, including polio and nonpolio enteroviruses. Most studies of wastewater surveillance did not link what was found in the wastewater to other measures of disease transmission. Among those studies that did, the value reported varied by study. Wastewater surveillance should be considered as a potential public health tool for many infectious diseases. Wastewater surveillance studies can be improved by incorporating other measures of disease transmission at the population-level including disease incidence and hospitalizations. [ABSTRACT FROM AUTHOR]

Latent class models (LCMs) combine the results of multiple diagnostic tests through a statistical model to obtain estimates of disease prevalence and diagnostic test accuracy in situations where there is no single, accurate reference standard. We performed a systematic review of the methodology and reporting of LCMs in diagnostic accuracy studies. This review shows that the use of LCMs in such studies increased sharply in the past decade, notably in the domain of infectious diseases (overall contribution: 59%). The 64 reviewed studies used a range of differently specified parametric latent variable models, applying Bayesian and frequentist methods. The critical assumption underlying the majority of LCM applications (61%) is that the test observations must be independent within 2 classes. Because violations of this assumption can lead to biased estimates of accuracy and prevalence, performing and reporting checks of whether assumptions are met is essential. Unfortunately, our review shows that 28% of the included studies failed to report any information that enables verification of model assumptions or performance. Because of the lack of information on model fit and adequate evidence “external” to the LCMs, it is often difficult for readers to judge the validity of LCM-based inferences and conclusions reached. [ABSTRACT FROM PUBLISHER]

Placental abruption and cardiovascular disease (CVD) have common etiological underpinnings, and there is accumulating evidence that abruption may be associated with future CVD. We estimated associations between abruption and coronary heart disease (CHD) and stroke. The meta-analysis was based on the random-effects risk ratio (RR) and 95% confidence interval (CI) as the effect measure. We conducted a bias analysis to account for abruption misclassification, selection bias, and unmeasured confounding. We included 11 cohort studies comprising 6,325,152 pregnancies, 69,759 abruptions, and 49,265 CHD and stroke cases (1967–2016). Risks of combined CVD morbidity-mortality among abruption and nonabruption groups were 16.7 and 9.3 per 1,000 births, respectively (RR = 1.76, 95% CI: 1.24, 2.50; I 2 = 94%; τ2 = 0.22). Women who suffered abruption were at 2.65-fold (95% CI: 1.55, 4.54; I 2 = 85%; τ2 = 0.36) higher risk of death related to CHD/stroke than nonfatal CHD/stroke complications (RR = 1.32, 95% CI: 0.91, 1.92; I 2 = 93%; τ2 = 0.15). Abruption was associated with higher mortality from CHD (RR = 2.64, 95% CI: 1.57, 4.44; I 2 = 76%; τ2 = 0.31) than stroke (RR = 1.70, 95% CI: 1.19, 2.42; I 2 = 40%; τ2 = 0.05). Corrections for the aforementioned biases increased these estimates. Women with pregnancies complicated by placental abruption may benefit from postpartum screening or therapeutic interventions to help mitigate CVD risks. [ABSTRACT FROM AUTHOR]

It is unclear whether dyslipidemia is associated with risk of colorectal neoplasia. The incidence of both conditions is increasing in Asia, motivating a number of new studies from this region. We performed a systematic literature search of Asian colonoscopy-based studies that collected blood lipid concentrations at the time of endoscopy. Persons found to have colorectal adenoma were considered cases, and those found to be adenoma-free were considered controls. Seventeen studies published between 2000 and 2014 met inclusion criteria, collectively enrolling 17,387 cases and 30,427 controls. Mean differences and adjusted odds ratios were summarized with random-effects meta-analyses. Compared with controls, cases had higher total cholesterol (mean difference (MD) = 2.4 mg/dL, 95% confidence interval (CI): 0.2, 4.6), higher low-density lipoprotein cholesterol (MD = 1.3 mg/dL, 95% CI: 0.1, 2.6), higher triglyceride (MD = 16.4 mg/dL, 95% CI: 11.2,21.5), and lower high-density lipoprotein (HDL) cholesterol (MD = -2.1 mg/dL, 95% CI: -2.7, -1.6) concentrations. Based on adjusted odds ratios, associations for 40-mg/dL-higher triglyceride levels (odds ratio = 1.13, 95% CI: 1.05,1.21) and 10-mg/dL-higher HDL cholesterol levels (odds ratio = 0.96, 95% CI: 0.92, 1.00) achieved statistical significance. Persons with adenoma were more likely to have unfavorable cholesterol profiles at the time of colonoscopy than those without adenoma. The most convincing evidence for an association between dyslipidemia and colorectal neoplasia was observed for hypertriglyceridemia. [ABSTRACT FROM AUTHOR]

During the 2009 influenza pandemic, uncertainty surrounding the severity of human infections with the influenza A(H1N1)pdm09 virus hindered the calibration of the early public health response. The case fatality risk was widely used to assess severity, but another underexplored and potentially more immediate measure is the hospitalization fatality risk (HFR), defined as the probability of death among H1N1 pdm09 cases who required hospitalization for medical reasons. In this review, we searched for relevant studies published in MEDLINE (PubMed) and EMBASE between April 1, 2009, and January 9, 2014. Crude estimates of the HFR ranged from 0% to 52%, with higher estimates from tertiary-care referral hospitals in countries with a lower gross domestic product, but in wealthy countries the estimate was 1%-3% in all settings. Point estimates increased substantially with age and with lower gross domestic product. Early in the next pandemic, estimation of a standardized HFR may provide a picture of the severity of infection, particularly if it is presented in comparison with a similarly standardized HFR for seasonal influenza in the same setting. [ABSTRACT FROM AUTHOR]

We conducted a meta-analysis of randomized controlled trials to examine the association of mobile phone intervention with net change in weight-related measures among overweight and obese adults. We searched electronic databases and conducted a bibliography review to identify articles published between the inception date of each database and March 27, 2014. Fourteen trials (including 1,337 participants in total) that met the eligibility criteria were included. Two investigators independently abstracted information on study characteristics and study outcomes. Net change estimates comparing the intervention group with the control group were pooled across trials using random-effects models. Compared with the control group, mobile phone intervention was associated with significant changes in body weight and body mass index (weight (kg)/height (m)2) of −1.44 kg (95% confidence interval (CI): −2.12, −0.76) and −0.24 units (95% CI: −0.40, −0.08), respectively. Subgroup analyses revealed that the associations were consistent across study-duration and intervention-type subgroups. For example, net body weight changes were −0.92 kg (95% CI: −1.58, −0.25) and −1.85 kg (95% CI: −2.99, −0.71) in trials of shorter (<6 months) and longer (≥6 months) duration, respectively. These findings provide evidence that mobile phone intervention may be a useful tool for promoting weight loss among overweight and obese adults. [ABSTRACT FROM PUBLISHER]

Asthma and wheezing disorders are common chronic health problems in childhood. Breastfeeding provides health benefits, but it is not known whether or how breastfeeding decreases the risk of developing asthma. We performed a systematic review and meta-analysis of studies published between 1983 and 2012 on breastfeeding and asthma in children from the general population. We searched the PubMed and Embase databases for cohort, cross-sectional, and case-control studies. We grouped the outcomes into asthma ever, recent asthma, or recent wheezing illness (recent asthma or recent wheeze). Using random-effects meta-analyses, we estimated pooled odds ratios of the association of breastfeeding with the risk for each of these outcomes. We performed meta-regression and stratified meta-analyses. We included 117 of 1,464 titles identified by our search. The pooled odds ratios were 0.78 (95% confidence interval: 0.74, 0.84) for 75 studies analyzing “asthma ever,” 0.76 (95% confidence interval: 0.67, 0.86) for 46 studies analyzing “recent asthma,” and 0.81 (95% confidence interval: 0.76, 0.87) for 94 studies analyzing recent wheezing illness. After stratification by age, the strong protective association found at ages 0–2 years diminished over time. We found no evidence for differences by study design or study quality or between studies in Western and non-Western countries. A positive association of breastfeeding with reduced asthma/wheezing is supported by the combined evidence of existing studies. [ABSTRACT FROM PUBLISHER]

Tubal sterilization is a common form of contraception in the United States and is hypothesized to be associated with a lower risk of breast cancer. However, prior observational studies have reported inconsistent results. We investigated the association between tubal sterilization and breast cancer risk among 77,249 postmenopausal, cancer-free women in the Cancer Prevention Study II (CPS-II) Nutrition Cohort, enrolled in 21 states in the United States during 1992–1993. During 15 years of follow-up through June 30, 2007, 4,084 invasive breast cancer cases were diagnosed. Multivariable Cox proportional hazard regression was used to estimate hazard ratios and 95% confidence intervals. A meta-analysis including the CPS-II Nutrition Cohort results with other published results from 4 case-control studies and 3 prospective studies was conducted to provide a summary estimate for the association between tubal sterilization and breast cancer risk. In the CPS-II Nutrition Cohort, tubal sterilization was not associated with breast cancer incidence (multivariable-adjusted hazard ratio = 1.08, 95% confidence interval: 0.97, 1.20). Associations stratified by year of tubal sterilization, age, and time since surgery were also null. The meta-analysis also found no association between tubal sterilization and breast cancer risk (odds ratio = 0.97, 95% confidence interval: 0.84, 1.09). Tubal sterilization does not appear to be associated with breast cancer risk. [ABSTRACT FROM PUBLISHER]

Recombinant human growth hormone (rhGH) therapy is used in the long-term treatment of children with growth disorders, but there is considerable treatment response variability. The exon 3-deleted growth hormone receptor polymorphism (GHRd3) may account for some of this variability. The authors performed a systematic review (to April 2011), including investigator-only data, to quantify the effects of the GHRfl-d3 and GHRd3-d3 genotypes on rhGH therapy response and used a recently established Bayesian inheritance model-free approach to meta-analyze the data. The primary outcome was the 1-year change-in-height standard-deviation score for the 2 genotypes. Eighteen data sets from 12 studies (1,527 children) were included. After several prior assumptions were tested, the most appropriate inheritance model was codominant (posterior probability = 0.93). Compared with noncarriers, carriers had median differences in 1-year change-in-height standard-deviation score of 0.09 (95% credible interval (CrI): 0.01, 0.17) for GHRfl-d3 and of 0.14 (95% CrI: 0.02, 0.26) for GHRd3-d3. However, the between-study standard deviation of 0.18 (95% CrI: 0.10, 0.33) was considerable. The authors tested by meta-regression for potential modifiers and found no substantial influence. They conclude that 1) the GHRd3 polymorphism inheritance is codominant, contrasting with previous reports; 2) GHRd3 genotypes account for modest increases in rhGH effects in children; and 3) considerable unexplained variability in responsiveness remains. [ABSTRACT FROM PUBLISHER]