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The Study to Explore Early Development (SEED) is a multi-site case-control study designed to explore the relationship between autism spectrum disorder (ASD) phenotypes and etiologies. The goals of this paper are to (1) describe the SEED algorithm that uses the Autism Diagnostic Interview-Revised (ADI-R) and Autism Diagnostic Observation Schedule (ADOS) to classify children with ASD, (2) examine psychometric properties of different ASD classification methods, including the SEED method that incorporates rules for resolving ADI-R and ADOS discordance, and (3) determine whether restricted interests and repetitive behaviors were noted for children who had instrument discordance resolved using ADI-R social and communication scores. Results support the utility of SEED criteria when well-defined groups of children are an important clinical or research outcome. [ABSTRACT FROM AUTHOR]

Anesthesia workspaces are integral components in the chains of many intraoperative bacterial transmission events resulting in surgical site infections (SSI). Matched cohort designs can be used to compare SSI rates among operating rooms (ORs) with or without capital equipment purchases (e.g., new anesthesia machines). Patients receiving care in intervention ORs (i.e., with installed capital equipment) are matched with similar patients receiving care in ORs lacking the intervention. We evaluate statistical power of an alternative design for clinical trials in which, instead, SSI incidences are compared directly among ORs (i.e., the ORs form the clusters) at single hospitals (e.g., the 5 ORs with bactericidal lights vs. the 5 other ORs). Data used for parameter estimates were SSI for 24 categories of procedures among 338 hospitals in the State of California, 2015. Estimated statistical power was ≅8.4% for detecting a reduction in the incidence of SSI from 3.6% to 2.4% over 1 year with 5 intervention ORs and 5 control ORs. For ≅80% statistical power, >20 such hospitals would be needed to complete a study in 1 year. Matched paired cluster designs pair similar ORs (e.g., 2 cardiac ORs, 1 to intervention and 1 to control). With 5 pairs, statistical power would be even less than the estimated 8.4%. Cluster designs (i.e., analyses by OR) are not suitable for comparing SSI among ORs at single hospitals. Even though matched cohort designs are non-randomized and thus have lesser validity, matching patients by their risk factors for SSI is more practical. [ABSTRACT FROM AUTHOR]

Purpose: Hypertension in pregnancy has been associated with decreased future risk of breast cancer in many but not all studies. In the Marin Women's Study, pregnancy-induced hypertension was shown to interact with the T allele of a functional IGF1R gene variant, rs2016347, to result in lower breast density, as well as decreased breast cancer risk. Our objective was to explore these findings in a larger sample of women from the California Teachers Study (CTS).Methods: The CTS cohort consists of over 130,000 female educators. DNA was available from a nested case-control study, which included 2,030 non-Hispanic white women who developed breast cancer and 1,552 controls. The current study included all participants from the case-control group with a self-reported history of preeclampsia (80 cases/57 controls).Results: Comparing TT to GG genotypes revealed adjusted odds ratios of 0.38 (CI 0.13, 1.14) for all invasive breast cancers, 0.26 (CI 0.07, 0.89) for hormone receptor-positive (HR+) breast cancers, 0.15 (CI 0.04, 0.56) for those with age at first birth (AFB) < 30, and 0.10 (CI 0.02, 0.49) for those with AFB < 30 and HR+ breast cancers. Trend analysis yielded p values of 0.09, 0.03, 0.005, and 0.004 respectively, suggesting a biological effect for each T allele.Conclusion: Study findings indicate that the T allele of IGF1R variant rs2016347 is associated with a significant reduction in breast cancer risk in women with a history of preeclampsia, most marked for HR+ breast cancer and in women with AFB < 30. [ABSTRACT FROM AUTHOR]

Purpose: Studies have reported an increased risk of childhood leukemia associated with exposure to magnetic fields. We conducted a large records-based case-control study of childhood leukemia risk and exposure to magnetic fields from power lines in California.Methods: The study included 5,788 childhood leukemia cases (born in and diagnosed in California 1986-2008) matched to population-based controls on age and sex. We calculated magnetic fields at birth addresses using geographic information systems, aerial imagery, historical information on load and phasing, and site visits.Results: Based on unconditional logistic regression controlling for age, sex, race/ethnicity, and socioeconomic status using subjects geocoded to a basic standard of accuracy, we report a slight risk deficit in two intermediate exposure groups and a small excess risk in the highest exposure group (odds ratio of 1.50 (95% confidence interval [0.70, 3.23])). Subgroup and sensitivity analyses as well as matched analyses gave similar results. All estimates had wide confidence intervals.Conclusion: Our large, statewide, record-based case-control study of childhood leukemia in California does not in itself provide clear evidence of risk associated with greater exposure to magnetic fields from power lines, but could be viewed as consistent with previous findings of increased risk. [ABSTRACT FROM AUTHOR]

Objectives Despite being encouraged to take pre-natal supplements, suboptimal micronutrient intake is common in pregnancy, especially among Hispanic women. In this study, we assessed whether initiation and timing of pre-natal vitamin use influences the risk of preterm birth. Methods Women who gave birth to singletons in 2003 in Los Angeles County, California, were enrolled into a population-based case-control study. Focusing on non-Hispanic white and Hispanic women, associations between timing of pre-natal supplement use and preterm birth were assessed using logistic regression. Results Among Hispanic mothers, the odds of preterm birth increased the later a woman initiated pre-natal supplement use in pregnancy. The magnitude of this association was larger in US-born compared to foreign-born Hispanic women. Conclusions These findings suggest that nativity may modify the relationship between pre-natal supplement use and preterm birth possibly due to underlying differences in diet composition of Hispanic women by place of birth. [ABSTRACT FROM AUTHOR]

Purpose: Folate, vitamins B12 and B6, riboflavin, and methionine are critical nutrients for the one-carbon metabolism cycle involved in DNA synthesis and epigenetic processes. We examined the association between maternal intake of these nutrients before pregnancy and risk of childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) in a matched case-control study.Methods: Maternal dietary intake and vitamin supplement use in the year before pregnancy was assessed by food frequency questionnaire for 681 ALL cases, 103 AML cases, and 1076 controls. Principal component analysis was used to construct a variable representing combined nutrient intake, and conditional logistic regression estimated the odds ratio (OR) and 95% confidence interval (CI) for the association of ALL and AML with the principal component and each nutrient.Results: Higher maternal intake of one-carbon metabolism nutrients from food and supplements combined was associated with reduced risk of ALL (OR for one-unit change in the principal component = 0.91, CI 0.84-0.99) and possibly AML (OR for the principal component = 0.83, CI 0.66-1.04). When analyzed separately, intake of supplements high in these nutrients was associated with a reduced risk of ALL in children of Hispanic women only.Conclusions: In conclusion, these data suggest that higher maternal intake of one-carbon metabolism nutrients may reduce risk of childhood leukemia. [ABSTRACT FROM AUTHOR]

We conducted a nested case-control study including 407 cases and 2,075 frequency matched controls to investigate the association between maternal infections during pregnancy and risk of autism spectrum disorders (ASD). Cases, controls, and maternal infections were ascertained from Kaiser Permanente Northern California clinical databases. No overall association between diagnoses of any maternal infection during pregnancy and ASD was observed [adjusted odds ratio (OR) = 1.15, 95 % confidence interval (CI) 0.92-1.43]. However, women with infections diagnosed during a hospital admission (OR = 1.48, 95 % CI 1.07-2.04), particularly bacterial infections (OR = 1.58, 95 % CI 1.06-2.37), were at increased risk of delivering a child with ASD. Multiple infections during pregnancy were associated with ASD (OR = 1.36, 95 % CI 1.05-1.78). [ABSTRACT FROM AUTHOR]

Thyroid hormones are critical for normal brain development. This study examined autism spectrum disorders (ASD) and thyroid stimulating hormone (TSH) levels measured in mid-pregnancy maternal serum and infant blood after birth. Three groups of children born in Orange County, CA in 2000-2001were identified: ASD (n = 78), developmental delay (n = 45), and general population controls (GP) (n = 149). Samples were retrieved from prenatal and newborn screening specimen archives. Adjusted logistic regression models showed inverse associations between ASD and log transformed TSH levels in maternal serum samples (ASD vs. GP: OR [95 % CI] 0.33 [0.12-0.91], Early Onset ASD vs. GP: 0.31 [0.10-0.98]). Results for thyroid levels in newborn blood samples were similar though not significant (ASD vs. GP: 0.61 [0.18-2.04]). [ABSTRACT FROM AUTHOR]

We conducted a large epidemiologic case-control study in California to examine the association between childhood cancer risk and distance from the home address at birth to the nearest high-voltage overhead transmission line as a replication of the study of Draper et al. in the United Kingdom. We present a detailed description of the study design, methods of case ascertainment, control selection, exposure assessment and data analysis plan. A total of 5788 childhood leukemia cases and 3308 childhood central nervous system cancer cases (included for comparison) and matched controls were available for analysis. Birth and diagnosis addresses of cases and birth addresses of controls were geocoded. Distance from the home to nearby overhead transmission lines was ascertained on the basis of the electric power companies' geographic information system (GIS) databases, additional Google Earth aerial evaluation and site visits to selected residences. We evaluated distances to power lines up to 2000 m and included consideration of lower voltages (60-69 kV). Distance measures based on GIS and Google Earth evaluation showed close agreement (Pearson correlation >0.99). Our three-tiered approach to exposure assessment allowed us to achieve high specificity, which is crucial for studies of rare diseases with low exposure prevalence. [ABSTRACT FROM AUTHOR]

We investigated whether there is an association between increased risk for autism spectrum disorders (ASD) and selective serotonin reuptake inhibitors (SSRIs) used during pregnancy. This study used Denmark's health and population registers to obtain information regarding prescription drugs, ASD diagnosis, and health and socioeconomic status. There were 1.5 % of cases and 0.7 % of controls exposed to SSRIs during the pregnancy period, and higher effect estimates observed with longer use. We found evidence that in utero exposure to SSRIs increases a child's risk associated with ASD. These results, while adding to the limited knowledge on prenatal pharmacological exposures as potential ASD risk factors, need to be balanced against the benefits of indicated medication use by pregnant mothers. [ABSTRACT FROM AUTHOR]

Previous studies of memory in autism spectrum conditions (ASC) have consistently shown that persons with ASC have reduced memories for social information, relative to a spared memory for non-social facts. The current study aims to reproduce these findings, while examining the possible causes leading to this difference. Participants' memory for trait-words was tested after they had viewed the words in three study contexts: visuo-motor, letter-detection, and social judgment. While participants with ASC showed a levels-of-processing effect, such that their memory for words viewed in the social judgment context was greater than their memory for words viewed in the letter-detection context, their memory for socially-processed words was reduced relative to comparison participants. This interaction effect could not be explained by a speed/accuracy trade-off, nor could it be explained solely by differences in encoding. These results suggest that social memory deficits in ASC arise from difficulties both in orienting towards and encoding social content, as well as retaining and retrieving it. Implications for theory and clinical practice are discussed. [ABSTRACT FROM AUTHOR]

The current study tested fine discrimination of upright and inverted faces and objects in adolescents with Autism Spectrum Disorder (ASD) as compared to age- and IQ-matched controls. Discrimination sensitivity was tested using morphed faces and morphed objects, and all stimuli were equated in low-level visual characteristics (luminance, contrast, spatial frequency make-up). Participants with ASD exhibited slight, non-significant impairments in discrimination sensitivity for faces, yet significantly enhanced discrimination sensitivity for objects. The ASD group also showed a protracted development of face and object inversion effects. Finally, for ASD participants, face sensitivity improved with increasing IQ while object sensitivity improved with age. By contrast, for controls, face sensitivity improved with age, but neither face nor object sensitivity was influenced by IQ. These findings suggest that individuals with ASD follow a qualitatively different path in the development of face and object processing abilities. [ABSTRACT FROM AUTHOR]

Early return to work after childbirth has been increasing among working mothers in the US. We assessed the relationship between access to employer-offered maternity leave (EOML) (both paid and unpaid) and uptake and duration of maternity leave following childbirth in a socio-economically diverse sample of full-time working women. We focus on California, a state that has long provided more generous maternity leave benefits than those offered by federal maternity leave policies through the State Disability Insurance program. The sample included 691 mothers who gave birth in Southern California in 2002-2003. Using weighted logistic regression, we examined the EOML-maternity leave duration relationship, controlling for whether the leave was paid, as well as other occupational, personality and health-related covariates. Compared with mothers who were offered more than 12 weeks of maternity leave, mothers with <6 weeks of EOML and those offered 6-12 weeks had five times higher odds of returning to work within 12 weeks; those offered no leave had six times higher odds of an early return. These relationships were similar after controlling for whether the leave was paid and after controlling for other occupational and health characteristics. Access to and duration of employer-offered maternity leave significantly determine timing of return to work following childbirth, potentially affecting work-family balance. Policy makers should recognize the pivotal role of employers in offering job security during and after maternity leave and consider widening the eligibility criteria of the Family and Medical Leave Act. [ABSTRACT FROM AUTHOR]

Concerns persist about a possible link between infertility and risk of autism spectrum disorders (ASD). Interpretation of existing studies is limited by racial/ethnic homogeneity of study populations and other factors. Using a case-control design, we evaluated infertility history and treatment documented in medical records of members of Kaiser Permanente Northern California. Among singletons (349 cases, 1,847 controls), we found no evidence to support an increase in risk of ASD associated with infertility. Among multiple births (21 cases, 54 controls), we found an increased risk associated with infertility history and with infertility evaluations and treatment around the time of index pregnancy conception; however, small sample size and lack of detailed data on treatments preclude firm interpretation of results for multiple births. [ABSTRACT FROM AUTHOR]

Objective:To examine the risk and etiology of preterm delivery in women with polycystic ovary syndrome (PCOS).Study Design:Retrospective cohort study comparing preterm delivery rate among non-diabetic PCOS and non-PCOS women with singleton pregnancy. Multivariable logistic regression was used to identify predictors of preterm delivery among PCOS women.Result:Among 908 PCOS women with singleton pregnancy, 12.9% delivered preterm compared with 7.4% among non-PCOS women (P<0.01). Causes of preterm delivery among PCOS women included preterm labor (41%), cervical insufficiency (11%), hypertensive complications (20%), preterm premature rupture of membranes (15%), fetal-placental concerns (9%) and intrauterine fetal demise (5%). Maternal age, race/ethnicity and nulliparity were significant predictors of preterm delivery in PCOS, whereas body mass index and fertility medications were not.Conclusion:A higher proportion of PCOS women delivered preterm (12.9%) compared with non-PCOS women, with the majority of cases due to spontaneous preterm birth. Future studies should explore etiologies and strategies to improve pregnancy outcomes in PCOS. [ABSTRACT FROM AUTHOR]

Whereas preterm birth has consistently been associated with low maternal pre-pregnancy weight, the relationship with high pre-pregnancy weight has been inconsistent. We quantified the pre-pregnancy BMI-preterm delivery (PTD) relationship using traditional BMI categories (underweight, normal weight, overweight and obese) as well as continuous BMI. Eligible women participated in California's statewide prenatal screening program, worked during pregnancy, and delivered a live singleton birth in Southern California in 2002-2003. The final analytic sample included 354 cases delivering at <37 weeks, as identified by clinical estimate of gestational age from screening records, and 710 term normal-birthweight controls. Multivariable logistic regression models using categorical BMI levels and continuous BMI were compared. In categorical analyses, PTD was significantly associated with pre-pregnancy underweight only. Nonparametric local regression revealed a V-shaped relationship between continuous BMI and PTD, with minimum risk at the high end of normal, around 24 kg/m. The odds ratio (OR) for PTD associated with low BMI within the normal range (19 kg/m) was 2.84 (95%CI = 1.61-5.01); ORs for higher BMI in the overweight (29 kg/m) and obese (34 kg/m) ranges were 1.42 (95%CI = 1.10-1.84) and 2.01 (95% CI = 1.20-3.39) respectively, relative to 24 kg/m). BMI categories obscured the preterm delivery risk associated with low-normal, overweight, and obese BMI. We found that higher BMI up to around 24 kg/m is increasingly protective of preterm delivery, beyond which a higher body mass index becomes detrimental. Current NHLBI/WHO BMI categories may be inadequate for identifying women at higher risk for PTD. [ABSTRACT FROM AUTHOR]

Background and Aim: Intestinal and extra-intestinal complications are associated with inflammatory bowel disease (IBD) but their exact incidence is not well known. In order to improve our understanding of their incidence and impact, we assessed the complications associated with ulcerative colitis (UC) and Crohn's disease (CD) in a population-based study in Medicaid patients.Methods: We utilized a retrospective cohort design and identified cases of UC and CD using Medi-Cal, the Medicaid program for the State of California. The disease cohort was age- and gender-matched to four controls each and the intestinal and extra-intestinal complications of CD and UC (analyzed separately) were studied over a period of 5 years following the initial diagnosis.Results: For UC, the total number of intestinal complications, per 100 cases, was 92 observed compared to 21 expected; the total number of extra-intestinal complications was 42 observed compared to 30 expected. For CD, the number of intestinal complications was 81 observed compared to 20 expected and for extra-intestinal complications, 37 observed compared to 26 expected (all p < 0.001). For both UC and CD, bleeding was the most frequently seen intestinal complication, while the most common extra-intestinal complication was osteoporosis.Conclusions: IBD is associated with several intestinal and extra-intestinal complications of variable incidence and risk. Success of therapeutic regimens should be measured by decreases in incidence, risks, and costs of these complications, in addition to the usual impact on disease activity. [ABSTRACT FROM AUTHOR]

A cohort of 197 Medicaid-insured patients presenting for treatment in Kaiser Permanente's outpatient chemical dependency treatment program were observed the year prior to their program intake visit and followed for 3 years afterwards, to compare their medical costs and utilization to demographically matched commercially insured patients entering the same programs. The Medicaid-insured patients on average incurred medical costs 60% higher than non-Medicaid patients during the 12-month preintake period ($5402 vs $3377). [corrected] During the 3 years subsequently, however, both groups of chemical dependency patients displayed significant declines in medical costs, averaging 30% from the baseline period to the third year of follow-up. Cost trends reflected declines in use of hospital days, emergency department visits, and nonemergent outpatient visits. These results may help address concerns among Medicaid managed care providers and payers by giving a more realistic account of the long-term costs of this group of high-utilizing enrollees. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the role of parental occupations in the etiology of childhood brain tumors (CBT).Methods: Population-based case-control studies were conducted concurrently in seven countries under the coordination of the International Agency for Research on Cancer, gathering 1,218 cases and 2,223 controls. We report here the findings related to parental occupations during the 5-year period before the child's birth. Risk estimates related to a number of paternal and maternal occupations were obtained by unconditional logistic regression adjusted for age, sex, year of birth, and center, for all types of CBT combined and for the subgroups of astroglial, primitive neuroectodermal tumors (PNET), and other glial tumors.Results: An increased risk in relation with agricultural work was seen for all CBT combined and for other glial tumors. Increased risks for all tumors and PNET were seen for paternal occupation as an electrician; the same pattern held for maternal occupation when children under 5 were selected. Paternal occupation as a driver or mechanic, and maternal work in an environment related to motor-vehicles were associated with an increased risk for all CBT and astroglial tumors. More case mothers compared to control mothers were employed in the textile industry.Conclusion: Our study reinforces previous findings relative to the role of parental work in agriculture, electricity, or motor-vehicle related occupations and maternal work in the textile industry. It does not confirm previous associations with work environments including aerospace, the chemical industry, or the food industry, or with maternal occupation as a hairdresser, a nurse, or a sewing machinist, and paternal occupation as a welder. [ABSTRACT FROM AUTHOR]

Objectives: Sigmoidoscopy screening and fecal occult blood (FOB) tests have been demonstrated as effective ways to reduce mortality from colorectal cancer. However, most studies of colorectal cancer screening and cancer mortality have not taken into consideration lifestyle factors that could account for the observed associations. The purpose of this study was to determine the association between screening and incidence of colon cancer, taking into consideration important lifestyle factors.Methods: We estimated the association between screening and colon cancer after taking into consideration health and lifestyle factors using data obtained as part of population-based case-control study of incident colon cancers.Results: Sigmoidoscopy screening, especially as part of a checkup, was protective against incident colon cancer in both men (OR 0.56, 95% CI 0.44-0.77) and women (OR 0.53, 95% CI 0.33-0.77) after adjusting for other risk factors for colon cancer. For men, associations were stronger for distal tumors (OR 0.48, 95% CI 0.31-0.71) than for proximal tumors (OR 0.67, 95% CI 0.45-1.11). We did not observe significant associations between FOB test and colon cancer. Differences in characteristics between those who were screened and not screened were also observed. Men were more likely to report having a sigmoidoscopy as part of a checkup than were women, as were people with higher levels of education. People who reported having a sigmoidoscopy as part of a checkup also reported eating diets lower in fat and higher in fiber, folate, and vegetables. Men were more likely to report higher levels of physical activity, and women were more likely to report taking hormone replacement therapy (HRT) if they also reported a sigmoidoscopy. Both men and women who reported a sigmoidoscopy for screening purposes were more likely to have a family history of colorectal cancer.Conclusions: These data provide additional support for the benefits of having a screening sigmoidoscopy. The associations between screening sigmoidoscopy and colon cancer do not appear to be the result of lifestyle factors. [ABSTRACT FROM AUTHOR]

The often observed association between red meat and colorectal cancer could be due in part to mutagens, such as heterocyclic amines (HCA), that are present in cooked meat. HCAs are highly mutagenic and cause intestinal tumors in animals. The hypothesis that HCAs are also carcinogenic to humans remains to be substantiated in epidemiologic studies. We determined the associations of meat preparation and frequency of intake (proxy variables for HCA exposure, since HCA concentration depends on the type of meat and the way it is cooked) with the prevalence of distal colorectal adenomas in a sigmoidoscopy-based case-control study of 488 matched pairs of subjects from two California (United States) Kaiser Permanente Medical Centers. A more than twofold difference in adenoma prevalence between subjects at extreme ends of estimated HCA intake was observed. For subjects who ate red meat more than once per week, fried it more than 10 percent of the time, and ate it with a darkly browned surface, compared with subjects who ate red meat one time or less per week, fried it 10 or less percent of the time, and ate it with a lightly browned surface, the odds ratio was 2.2 (95 percent confidence interval = 1.1-4.3). Adenoma prevalence also increased with frequency of frying red meat (P trend = 0.004). These results are consistent with a carcinogenic effect of HCA. [ABSTRACT FROM AUTHOR]