The effect of PAP on UACR and metabolic indexes in patients with MS and OSAHS.

PURPOSE: To investigate the effects of positive airway pressure (PAP) device on urinary albumin to creatinine ratio (UACR) and metabolic indexes in patients with metabolic syndrome (MS) and obstructive sleep apnea-hypopnea syndrome (OSAHS). METHODS: This study is a retrospective cohort study. Grouped according to whether to use PAP treatment, there were 25 cases in the PAP group and 44 cases in the no OSAHS treatment group. The PAP group received positive airway pressure device and routine treatment of MS. The no OSAHS treatment group received routine treatment of OSAHS and MS. The treatment period is 3 months. RESULTS: 1. The PAP group demonstrated significant reductions in Body Mass Index (BMI), Waist circumference (WC), Neck circumference (NC), Visceral fat area (VFA), Fasting C peptide (FCP), high-sensitivity C-reactive protein (hs-CRP), and UACR compared to the no OSAHS treatment group, with significant differences (P all <0.05). Among them, the UACR in the PAP group decreased significantly (from 86.05(52.55,131.61)mg/g to 16.76(8.70,25.12)mg/g, P<0.001). 2. Linear regression analysis using the decrease in UACR values as the dependent variable demonstrated a positive linear relationship with the decrease in BMI, VFA, fasting insulin (FINS), and homeostasis model assessment of insulin resistance (HOMA-IR). Furthermore, multiple linear regression analysis indicated that the decrease in VFA (B=0.537 [95% confidence interval, 0.084 to 0.989]; P = 0.021) and HOMA-IR (B=1.000 [95% confidence interval, 0.082 to 1.917]; P = 0.033) values independently correlated with decrease in UACR values. CONCLUSIONS: PAP treatment can reduce UACR in patients with MS and OSAHS, and has the effect of improving metabolic disorders. The decrease of UACR in patients may be related to the decrease of visceral fat and the improvement of insulin resistance.

Germline polymorphisms in MGMT associated with temozolomide-related myelotoxicity risk in patients with glioblastoma treated on NRG Oncology/RTOG 0825.

Background: We sought to identify clinical and genetic predictors of temozolomide-related myelotoxicity among patients receiving therapy for glioblastoma. Methods: Patients (n = 591) receiving therapy on NRG Oncology/RTOG 0825 were included in the analysis. Cases were patients with severe myelotoxicity (grade 3 and higher leukopenia, neutropenia, and/or thrombocytopenia); controls were patients without such toxicity. A risk-prediction model was built and cross-validated by logistic regression using only clinical variables and extended using polymorphisms associated with myelotoxicity. Results: 23% of patients developed myelotoxicity (n = 134). This toxicity was first reported during the concurrent phase of therapy for 56 patients; 30 stopped treatment due to toxicity. Among those who continued therapy (n = 26), 11 experienced myelotoxicity again. The final multivariable clinical factor model included treatment arm, gender, and anticonvulsant status and had low prediction accuracy (area under the curve [AUC] = 0.672). The final extended risk prediction model including four polymorphisms in MGMT had better prediction (AUC = 0.827). Receiving combination chemotherapy (OR, 1.82; 95% CI, 1.02-3.27) and being female (OR, 4.45; 95% CI, 2.45-8.08) significantly increased myelotoxicity risk. For each additional minor allele in the polymorphisms, the risk increased by 64% (OR, 1.64; 95% CI, 1.43-1.89). Conclusions: Myelotoxicity during concurrent chemoradiation with temozolomide is an uncommon but serious event, often leading to treatment cessation. Successful prediction of toxicity may lead to more cost-effective individualized monitoring of at-risk subjects. The addition of genetic factors greatly enhanced our ability to predict toxicity among a group of similarly treated glioblastoma patients.

Genetic modulation of longitudinal change in neurocognitive function among adult glioma patients.

PURPOSE: Impaired neurocognitive function (NCF) is extremely common in patients with higher grade primary brain tumor. We previously reported evidence of genetic variants associated with NCF in glioma patients prior to treatment. However, little is known about the effect of genetic variants on NCF decline after adjuvant therapy. METHODS: Patients (N = 102) completed longitudinal NCF assessments that included measures of verbal memory, processing speed, and executive function. Testing was conducted in the postoperative period with an average follow up interval of 1.3 years. We examined polymorphisms in 580 genes related to five pathways (inflammation, DNA repair, metabolism, cognitive, and telomerase). RESULTS: Five polymorphisms were associated with longitudinal changes in processing speed and 14 polymorphisms with executive function. Change in processing speed was strongly associated with MCPH1 rs17631450 (P = 2.2 × 10-7) and CCDC26 rs7005206 (P = 9.3 × 10-7) in the telomerase pathway; while change in executive function was more strongly associated with FANCF rs1514084 (P = 2.9 × 10-6) in the DNA repair pathway and DAOA rs12428572 (P = 2.4 × 10-5) in the cognitive pathway. Joint effect analysis found significant genetic-dosage effects for longitudinal changes in processing speed (Ptrend = 1.5 × 10-10) and executive function (Ptrend = 2.1 × 10-11). In multivariable analyses, predictors of NCF decline included progressive disease, lower baseline NCF performance, and more at-risk genetic variants, after adjusting for age, sex, education, tumor location, histology, and disease progression. CONCLUSION: Our longitudinal analyses revealed that polymorphisms in telomerase, DNA repair, and cognitive pathways are independent predictors of decline in NCF in glioma patients.

Palmitoleic Acid Protects against Hypertension by Inhibiting NF-κB-Mediated Inflammation.

SCOPE: The role of palmitoleic acid (POA) in hypertension or blood pressure remains uncertain. This study aims to investigate the epidemiological association between circulating POA and primary hypertension in humans, and subsequently evaluate the effects of exogenous POA on blood pressure and aortic remodeling in spontaneously hypertensive rats (SHRs). METHODS AND RESULTS: A case-control study of 349 hypertensive and 1396 normotensive children and adolescents is conducted, and found hypertensive cases show significant lower erythrocyte phospholipid POA than normotensive controls (p < 0.001). In conditional logistic regression model, participants in the top quartile of POA have a lower prevalence of primary hypertension than those in the bottom (multivariate-adjusted OR: 0.47, 95% CI: 0.25-0.89). In animal study, 24 SHRs are randomly assigned to n-3 PUFAs (500 mg kg-1 ), POA (500 mg kg-1 ), or vehicle (olive oil) for 8 weeks. At the end of intervention, as compared to SHRs treated with vehicle, SHRs treated with POA shows significantly decreased systolic blood pressure (SBP), improved aortic remodeling, and also decreased aortic expressions of NF-κB and its downstream proinflammatory cytokines. CONCLUSIONS: Circulating POA is inversely associated with risk of primary hypertension, and exogenous POA supplementation can decrease SBP and improve aortic remodeling by inhibiting NF-κB-mediated inflammation.

Effects of consuming red furu (fermented bean curd) on serum vitamin B-12, homocysteine and other cardiometabolic risk factors in young healthy volunteers: A randomized controlled trial.

BACKGROUND AND OBJECTIVES: The health benefits of red furu in young, healthy volunteers had not been adequately investigated. The aim of this study was to determine the effect of a single meal containing red furu on serum vitamin B-12 (B-12), homocysteine and other cardiometabolic risk factors compared with that of tofu. METHODS AND STUDY DESIGN: Twenty-three healthy volunteers from Zhejiang University, China, were randomly assigned to two groups of consumption, either red furu (n=11, 5 women and 6 men) or tofu (n=12, 6 women and 6 men). Volunteers consumed one breakfast meal composed of either 50 g of red furu (intervention group) or 50 g of tofu (non-active comparison group) with two slices of bread. Fasting blood was collected at 0 h, 24 h, and 72 h. Standard methods were used to measure the volunteers' biochemical parameters. RESULTS: The consumption of 50 g of red furu a day did not significantly affect serum B-12 and showed a non-significant trend to reduce serum homocysteine. In the red furu group, but not in tofu group, serum concentrations of B-12 and folate were negatively associated with homocysteine, and B-12 was positively associated with folate. CONCLUSIONS: A breakfast meal with 50 g of red furu containing 0.096 µg of B-12 did not increase serum B-12 in healthy volunteers. These results suggested that one meal containing B-12 could be sufficient to reduce serum Hcy.

Human milk microbiota development during lactation and its relation to maternal geographic location and gestational hypertensive status.

Bacteria in human milk could directly seed the infant intestinal microbiota, while information about how milk microbiota develops during lactation and how geographic location, gestational hypertensive status, and maternal age influence this process is limited. Here, we collected human milk samples from mothers of term infants at the first day, 2 weeks, and 6 weeks postpartum from 117 longitudinally followed-up mothers (age: 28.7 ± 3.6 y) recruited from three cities in China. We found that milk microbial diversity and richness were the highest in colostrum but gradually decreased over lactation. Microbial composition changed across lactation and exhibited more discrete compositional patterns in 2-week and 6-week milk samples compared with colostrum samples. At phylum level, the abundance of Proteobacteria increased during lactation, while Firmicutes showed the opposite trend. At genus level, Staphylococcus, Streptococcus, Acinetobacter, Pseudomonas, and Lactobacillus were predominant in colostrum samples and showed distinct variations across lactation. Maternal geographic location was significantly associated with the milk microbiota development and the abundance of predominant genus. In addition, milk from mothers with gestational prehypertension had a different and less diverse microbial community at genus level in early lactation times, and contained less Lactobacillus in the 2-week milk samples than those from normotensive mothers. Findings of our study outlined the human milk microbial diversity and community development over lactation, and underscored the importance of maternal geographic locations and gestational hypertensive status on milk microbiota, which might have important implications in the establishment of the infant intestinal microbiota via breastfeeding.

Habitual animal fat consumption in shaping gut microbiota and microbial metabolites.

Short-term intervention studies support a link between animal-based diet and the outgrowth of microorganisms capable of triggering inflammatory bowel disease. However, whether habitual animal fat intake is associated with gut-related health remains unclear. Thus, we collected dietary information, clinical data and fecal samples from 297 healthy young subjects and characterized gut microbiota by 16S rRNA gene sequencing and microbial metabolites, including short-chain fatty acids (SCFAs) and bile acids (BAs) using a gas chromatography coupled to time-of-flight mass spectrometry (GC-TOF/MS) system and ultra performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) platform, respectively. We found that the microbial diversity of butyric acid (rho = -0.17, p = 0.004 for the Shannon index) and the concentrations of butyric acid (rho = -0.33, p < 0.001) and valeric acid (rho = -0.28, p = 0.002) were negatively associated with animal fat consumption. In line with this, the abundance of SCFAs-producing bacteria such as Blautia, Eubacterium hallii, and Megamonas were significantly lower in the high animal fat group compared with the low animal fat group (all p < 0.05). Additionally, the high animal fat group had higher concentrations of total (p = 0.06) and unconjugated (p = 0.09) BAs relative to the lower animal fat groups. The findings of our study indicate that a diet with higher animal-based fat consumption is likely to be associated with moderately unfavorable impacts on gut microbial diversity, community, and regulation of fecal SCFAs, which may influence the host cardiometabolic health in the long term among healthy Chinese adults whose diet is in a nutrition transition.

Glioma-related seizures in relation to histopathological subtypes: a report from the glioma international case-control study.

BACKGROUND: The purpose of this study was to evaluate the distribution of glioma-related seizures and seizure control at the time of tumor diagnosis with respect to tumor histologic subtypes, tumor treatment and patient characteristics, and to compare seizure history preceding tumor diagnosis (or study enrollment) between glioma patients and healthy controls. METHODS: The Glioma International Case Control study (GICC) risk factor questionnaire collected information on demographics, past medical/medication history, and occupational history. Cases from eight centers were also asked detailed questions on seizures in relation to glioma diagnosis; cases (n = 4533) and controls (n = 4171) were also asked about seizures less than 2 years from diagnosis and previous seizure history more than 2 years prior to tumor diagnosis, including childhood seizures. RESULTS: Low-grade gliomas (LGGs), particularly oligodendrogliomas/oligoastrocytomas, had the highest proportion of glioma-related seizures. Patients with low-grade astrocytoma demonstrated the most medically refractory seizures. A total of 83% of patients were using only one antiepileptic drug (AED), which was levetiracetam in 71% of cases. Gross total resection was strongly associated with reduced seizure frequency (p < 0.009). No significant difference was found between glioma cases and controls in terms of seizure occurring more than 2 years before diagnosis or during childhood. CONCLUSIONS: Our study showed that glioma-related seizures were most common in low-grade gliomas. Gross total resection was associated with lower seizure frequency. Additionally, having a history of childhood seizures is not a risk factor ***for developing glioma-related seizures or glioma.

Association of genetic variants with fatigue in patients with malignant glioma.

BACKGROUND: Fatigue is a consistently reported, severe symptom among patients with gliomas throughout the disease trajectory. Genomic pathways associated with fatigue in glioma patients have yet to be identified. METHODS: Clinical factors (performance status, tumor details, age, gender) were collected by chart review on glioma patients with fatigue ("I have lack of energy" on Functional Assessment of Cancer Therapy-Brain), as well as available genotyping data. Candidate genes in clock and inflammatory pathways were identified from a literature review, of which 50 single nucleotide polymorphisms (SNPs) in 7 genes were available. Clinical factors and SNPs identified by univariate analyses were included in a multivariate model for moderate-severe fatigue. RESULTS: The study included 176 patients (median age = 47 years, 67% males). Moderate-severe fatigue was reported by 43%. Results from multivariate analysis revealed poor performance status and 2 SNPs were associated with fatigue severity. Moderate-severe fatigue was more common in patients with poor performance status (OR = 3.52, P < .01). For each additional copy of the minor allele in rs934945 (PER2) the odds of fatigue decreased (OR = 0.51, P < .05). For each additional copy of the minor allele in rs922270 (ARTNL2) the odds of fatigue increased (OR = 2.38, P < .01). Both of these genes are important in the circadian clock pathway, which has been implicated in diurnal preference, and duration and quality of sleep. No genes in the inflammatory pathway were associated with fatigue in the current study. CONCLUSIONS: Identifying patients at highest risk for fatigue during treatment allows for improved clinical monitoring and enrichment of patient selection for clinical trials.

Germline polymorphisms in myeloid-associated genes are not associated with survival in glioma patients.

Immune cells of myeloid origin, including microglia, macrophages, and myeloid-derived suppressor cells adopt immunosuppressive phenotypes that support gliomagenesis. Here, we tested an a priori hypothesis that single nucleotide polymorphisms (SNPs) in genes related to glioma-associated myeloid cell regulation and function are also associated with patient survival after glioma diagnosis. Subjects for this study were 992 glioma patients treated at The University of Texas MD Anderson Cancer Center in Houston, Texas between 1992 and 2008. Haplotype-tagging SNPs in 91 myeloid-associated genes were analyzed for association with survival by Cox regression. Individual SNP- and gene-based tests were performed separately in glioblastoma (WHO grade IV, n = 511) and lower-grade glioma (WHO grade II-III, n = 481) groups. After adjustment for multiple testing, no myeloid-associated gene variants were significantly associated with survival in glioblastoma. Two SNPs, rs147960238 in CD163 (p = 2.2 × 10-5) and rs17138945 in MET (p = 5.6 × 10-5) were significantly associated with survival of patients with lower-grade glioma. However, these associations were not confirmed in an independent analysis of 563 lower-grade glioma cases from the University of California at San Francisco Adult Glioma Study (p = 0.65 and p = 0.41, respectively). The results of this study do not support a role for inherited polymorphisms in myeloid-associated genes in affecting survival of patients diagnosed with glioblastoma or lower-grade glioma.

Analyzing semi-competing risks data with missing cause of informative terminal event.

Cancer studies frequently yield multiple event times that correspond to landmarks in disease progression, including non-terminal events (i.e., cancer recurrence) and an informative terminal event (i.e., cancer-related death). Hence, we often observe semi-competing risks data. Work on such data has focused on scenarios in which the cause of the terminal event is known. However, in some circumstances, the information on cause for patients who experience the terminal event is missing; consequently, we are not able to differentiate an informative terminal event from a non-informative terminal event. In this article, we propose a method to handle missing data regarding the cause of an informative terminal event when analyzing the semi-competing risks data. We first consider the nonparametric estimation of the survival function for the terminal event time given missing cause-of-failure data via the expectation-maximization algorithm. We then develop an estimation method for semi-competing risks data with missing cause of the terminal event, under a pre-specified semiparametric copula model. We conduct simulation studies to investigate the performance of the proposed method. We illustrate our methodology using data from a study of early-stage breast cancer. Copyright © 2016 John Wiley & Sons, Ltd.

History of chickenpox in glioma risk: a report from the glioma international case-control study (GICC).

Varicella zoster virus (VZV) is a neurotropic α-herpesvirus that causes chickenpox and establishes life-long latency in the cranial nerve and dorsal root ganglia of the host. To date, VZV is the only virus consistently reported to have an inverse association with glioma. The Glioma International Case-Control Study (GICC) is a large, multisite consortium with data on 4533 cases and 4171 controls collected across five countries. Here, we utilized the GICC data to confirm the previously reported associations between history of chickenpox and glioma risk in one of the largest studies to date on this topic. Using two-stage random-effects restricted maximum likelihood modeling, we found that a positive history of chickenpox was associated with a 21% lower glioma risk, adjusting for age and sex (95% confidence intervals (CI): 0.65-0.96). Furthermore, the protective effect of chickenpox was stronger for high-grade gliomas. Our study provides additional evidence that the observed protective effect of chickenpox against glioma is unlikely to be coincidental. Future studies, including meta-analyses of the literature and investigations of the potential biological mechanism, are warranted.

Approaching a Scientific Consensus on the Association between Allergies and Glioma Risk: A Report from the Glioma International Case-Control Study.

BACKGROUND: Several previous studies have found inverse associations between glioma susceptibility and a history of allergies or other atopic conditions. Some evidence indicates that respiratory allergies are likely to be particularly relevant with regard to glioma risk. Using data from the Glioma International Case-Control Study (GICC), we examined the effects of respiratory allergies and other atopic conditions on glioma risk. METHODS: The GICC contains detailed information on history of atopic conditions for 4,533 cases and 4,171 controls, recruited from 14 study sites across five countries. Using two-stage random-effects restricted maximum likelihood modeling to calculate meta-analysis ORs, we examined the associations between glioma and allergy status, respiratory allergy status, asthma, and eczema. RESULTS: Having a history of respiratory allergies was associated with an approximately 30% lower glioma risk, compared with not having respiratory allergies (mOR, 0.72; 95% confidence interval, 0.58-0.90). This association was similar when restricting to high-grade glioma cases. Asthma and eczema were also significantly protective against glioma. CONCLUSION: A substantial amount of data on the inverse association between atopic conditions and glioma has accumulated, and findings from the GICC study further strengthen the existing evidence that the relationship between atopy and glioma is unlikely to be coincidental. IMPACT: As the literature approaches a consensus on the impact of allergies in glioma risk, future research can begin to shift focus to what the underlying biologic mechanism behind this association may be, which could, in turn, yield new opportunities for immunotherapy or cancer prevention.

Genetic variations in the homologous recombination repair pathway genes modify risk of glioma.

Accumulative epidemiological evidence suggests that single nucleotide polymorphisms (SNPs) in genes involved in homologous recombination (HR) DNA repair pathway play an important role in glioma susceptibility. However, the effects of such SNPs on glioma risk remain unclear. We used a used a candidate pathway-based approach to elucidate the relationship between glioma risk and 12 putative functional SNPs in genes involved in the HR pathway. Genotyping was conducted on 771 histologically-confirmed glioma patients and 752 cancer-free controls from the Chinese Han population. Odds ratios (OR) were calculated both for each SNP individually and for grouped analyses, examining the effects of the numbers of adverse alleles on glioma risk, and evaluated their potential gene-gene interactions using the multifactor dimensionality reduction (MDR). In the single-locus analysis, two variants, the NBS1 rs1805794 (OR 1.42, 95% CI 1.15-1.76, P = 0.001), and RAD54L rs1048771 (OR 1.61, 95% CI 1.17-2.22, P = 0.002) were significantly associated with glioma risk. When we examined the joint effects of the risk-conferring alleles of these three SNPs, we found a significant trend indicating that the risk increases as the number of adverse alleles increase (P = 0.005). Moreover, the MDR analysis suggested a significant three-locus interaction model involving NBS1 rs1805794, MRE11 rs10831234, and ATM rs227062. These results suggested that these variants of the genes involved in the HR pathway may contribute to glioma susceptibility.

Semiparametric model for semi-competing risks data with application to breast cancer study.

For many forms of cancer, patients will receive the initial regimen of treatments, then experience cancer progression and eventually die of the disease. Understanding the disease process in patients with cancer is essential in clinical, epidemiological and translational research. One challenge in analyzing such data is that death dependently censors cancer progression (e.g., recurrence), whereas progression does not censor death. We deal with the informative censoring by first selecting a suitable copula model through an exploratory diagnostic approach and then developing an inference procedure to simultaneously estimate the marginal survival function of cancer relapse and an association parameter in the copula model. We show that the proposed estimators possess consistency and weak convergence. We use simulation studies to evaluate the finite sample performance of the proposed method, and illustrate it through an application to data from a study of early stage breast cancer.

The Glioma International Case-Control Study: A Report From the Genetic Epidemiology of Glioma International Consortium.

Decades of research have established only a few etiological factors for glioma, which is a rare and highly fatal brain cancer. Common methodological challenges among glioma studies include small sample sizes, heterogeneity of tumor subtypes, and retrospective exposure assessment. Here, we briefly describe the Glioma International Case-Control (GICC) Study (recruitment, 2010-2013), a study being conducted by the Genetic Epidemiology of Glioma International Consortium that integrates data from multiple data collection sites, uses a common protocol and questionnaire, and includes biospecimen collection. To our knowledge, the GICC Study is the largest glioma study to date that includes collection of blood samples, which will allow for genetic analysis and interrogation of gene-environment interactions.

Genetic Modulation of Neurocognitive Function in Glioma Patients.

PURPOSE: Accumulating evidence supports the contention that genetic variation is associated with neurocognitive function in healthy individuals and increased risk for neurocognitive decline in a variety of patient populations, including cancer patients. However, this has rarely been studied in glioma patients. EXPERIMENTAL DESIGN: To identify the effect of genetic variants on neurocognitive function, we examined the relationship between the genotype frequencies of 10,967 single-nucleotide polymorphisms in 580 genes related to five pathways (inflammation, DNA repair, metabolism, cognitive, and telomerase) and neurocognitive function in 233 newly diagnosed glioma patients before surgical resection. Four neuropsychologic tests that measured memory (Hopkins Verbal Learning Test-Revised), processing speed (Trail Making Test A), and executive function (Trail Making Test B, Controlled Oral Word Association) were examined. RESULTS: Eighteen polymorphisms were associated with processing speed and 12 polymorphisms with executive function. For processing speed, the strongest signals were in IRS1 rs6725330 in the inflammation pathway (P = 2.5 × 10(-10)), ERCC4 rs1573638 in the DNA repair pathway (P = 3.4 × 10(-7)), and ABCC1 rs8187858 in metabolism pathway (P = 6.6 × 10(-7)). For executive function, the strongest associations were in NOS1 rs11611788 (P = 1.8 × 10(-8)) and IL16 rs1912124 (P = 6.0 × 10(-7)) in the inflammation pathway, and POLE rs5744761 (P = 6.0 × 10(-7)) in the DNA repair pathway. Joint effect analysis found significant gene polymorphism-dosage effects for processing speed (Ptrend = 9.4 × 10(-16)) and executive function (Ptrend = 6.6 × 10(-15)). CONCLUSIONS: Polymorphisms in inflammation, DNA repair, and metabolism pathways are associated with neurocognitive function in glioma patients and may affect clinical outcomes.

A pooled multisite analysis of the effects of atopic medical conditions in glioma risk in different ethnic groups.

PURPOSE: The incidences of atopic conditions (allergies, asthma, or eczema) and glioma vary by ethnicity. Atopic conditions are inversely associated with gliomas. We conducted a pooled multisite study investigating the associations of atopic conditions with glioma in different race/ethnicity groups. METHODS: Using glioma cases and healthy controls, unconditional logistic regression was conducted to assess the associations of atopic conditions with glioma separately in white, black, Asian, and Hispanic subpopulations. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. RESULTS: Glioblastoma multiforme cases were less likely than controls to report a history of atopic conditions in whites (OR = 0.46, [95% CI, 0.38-0.54]) and Asians (OR = 0.27, [95% CI, 0.10-0.73]). The same trend was seen when looking at glioma cases of all histologies. An inverse association was not seen in blacks for glioblastoma multiforme or all histologies combined. CONCLUSIONS: The inverse association between glioma and atopic conditions may vary by ethnicity due to a difference in the biology of atopic conditions in different ethnicities but may be due to chance because of the limitations of small nonwhite sample sizes.

Maternal and birth characteristics and childhood rhabdomyosarcoma: a report from the Children's Oncology Group.

PURPOSE: Previous assessments of childhood rhabdomyosarcoma have indicated maternal and birth characteristics may be associated with tumor development; however, much work remains to identify novel and confirm suspected risk factors. Our objective was to evaluate the associations between maternal and birth characteristics and childhood rhabdomyosarcoma. METHODS: This case-control study included 322 cases and 322 pair-matched controls. Cases were enrolled in a trial run by the Intergroup Rhabdomyosarcoma Study Group. Population-based controls were identified using random digit dialing and were individually matched to cases on race, sex, and age. Families of the case and control subjects participated in a telephone interview, which captured information on maternal characteristics (birth control use, number of prenatal visits, anemia, and abnormal bleeding during pregnancy) and birth characteristics [birth weight, preterm birth, and type of delivery (vaginal vs. cesarean)]. Conditional logistic regression models were used to calculate an odds ratio (OR) and 95% confidence interval (CI) for each exposure, adjusted for age, race, sex, household income, and parental education. As the two most common histologic types of rhabdomyosarcoma are embryonal (n = 215) and alveolar (n = 66), we evaluated effect heterogeneity of these exposures. RESULTS: The only characteristic that was associated with childhood rhabdomyosarcoma, and statistically significant, was abnormal vaginal bleeding during pregnancy (OR 1.75, 95% CI 1.12-2.74). Birth control use (OR 1.45, 95% CI 0.96-2.18), anemia during pregnancy (OR 1.27, 95% CI 0.81-1.99), and preterm birth (OR 2.51, 95% CI 0.74-8.49) were positively associated with childhood rhabdomyosarcoma, but were not statistically significant. Low birth weight [adjusted odds ratios (aOR) 4.46, 95% CI 1.41-14.1] and high birth weight (aOR 2.41, 95% CI 1.09-5.35) were strongly associated with alveolar rhabdomyosarcoma. However, these factors did not display significant effect heterogeneity between histologic types (p > 0.15 for all characteristics). CONCLUSIONS: Overall, we found little evidence that these maternal and birth characteristics are strongly associated with childhood rhabdomyosarcoma.