Provider Specialization in Inflammatory Bowel Diseases: Quality of Care and Outcomes.

BACKGROUND: Management of inflammatory bowel diseases (IBD) is complex and variation in care has been well-documented. However, the drivers of practice variation remain unexplored. We examined variation based on the treating gastroenterologist's IBD focus (proportion of outpatient visits for IBD). METHODS: We conducted a retrospective cohort of newly diagnosed patients with IBD using data from Optum's de-identified Clinformatics® Data Mart Database (2000-2020). The exposure variable was whether the treating gastroenterologist had an IBD-focus (>90th percentile of IBD visits/total outpatient visits). We used adjusted regression models to evaluate associations between provider IBD focus and process measures (use of meslamine, corticosteroid, biologic and narcotic medications and endoscopic or radiographic imaging) and clinical outcomes (time to IBD-related hospitalization and bowel resection surgery). We tested for change in treatment patterns over time by including an interaction term for study era (2004-2012 versus 2013-2020). RESULTS: The study included 772 children treated by 493 providers and 2864 adults treated by 2076 providers. In children, none of the associations between provider focus and process or outcome measures were significant. In adults, care from an IBD-focused provider was associated with more use of biologics, combination therapy, and imaging and endoscopy, and less mesalamine use for Crohn's disease (P<.05 for all comparisons) but not with other process measures. Biologics were prescribed more frequently and narcotics less frequently during the later era (P<.05 for both). Hospitalization and surgery rates were not associated with IBD-focus or era. CONCLUSIONS: IBD care for adults varies by provider specialization. Given the evolving complexity, novel methods may be needed to standardize care.

Risk of Anaphylaxis Among New Users of GLP-1 Receptor Agonists: A Cohort Study.

OBJECTIVE: To assess risk of anaphylaxis among patients with type 2 diabetes mellitus who are initiating therapy with a glucagon-like peptide 1 receptor agonist (GLP-1 RA), with a focus on those starting lixisenatide therapy. RESEARCH DESIGN AND METHODS: A cohort study was conducted in three large, U.S. claims databases (2017-2021). Adult (aged ≥18 years) new users of a GLP-1 RA who had type 2 diabetes mellitus and ≥6 months enrollment in the database before GLP-1 RA initiation (start of follow-up) were included. GLP-1 RAs evaluated were lixisenatide, an insulin glargine/lixisenatide fixed-ratio combination (FRC), exenatide, liraglutide or insulin degludec/liraglutide FRC, dulaglutide, and semaglutide (injectable and oral). The first anaphylaxis event during follow-up was identified using a validated algorithm. Incidence rates (IRs) and 95% CIs were calculated within each medication cohort. The unadjusted IR ratio (IRR) comparing anaphylaxis rates in the lixisenatide cohort with all other GLP-1 RAs combined was analyzed post hoc. RESULTS: There were 696,089 new users with 456,612 person-years of exposure to GLP-1 RAs. Baseline demographics, comorbidities, and use of other prescription medications in the 6 months before the index date were similar across medication cohorts. IRs (95% CIs) per 10,000 person-years were 1.0 (0.0-5.6) for lixisenatide, 6.0 (3.6-9.4) for exenatide, 5.1 (3.7-7.0) for liraglutide, 3.9 (3.1-4.8) for dulaglutide, and 3.6 (2.6-4.9) for semaglutide. The IRR (95% CI) for the anaphylaxis rate for the lixisenatide cohort compared with the pooled other GLP-1 RA cohort was 0.24 (0.01-1.35). CONCLUSIONS: Anaphylaxis is rare with GLP-1 RAs. Lixisenatide is unlikely to confer higher risk of anaphylaxis than other GLP-1 RAs.

Pediatric Medical Subspecialist Use in Outpatient Settings.

Importance: A first step toward understanding whether pediatric medical subspecialists are meeting the needs of the nation's children is describing rates of use and trends over time. Objectives: To quantify rates of outpatient pediatric medical subspecialty use. Design, Setting, and Participants: This repeated cross-sectional study of annual subspecialist use examined 3 complementary data sources: electronic health records from PEDSnet (8 large academic medical centers [January 1, 2010, to December 31, 2021]); administrative data from the Healthcare Integrated Research Database (HIRD) (14 commercial health plans [January 1, 2011, to December 31, 2021]); and administrative data from the Transformed Medicaid Statistical Information System (T-MSIS) (44 state Medicaid programs [January 1, 2016, to December 31, 2019]). Annual denominators included 493 628 to 858 551 patients younger than 21 years with a general pediatric visit in PEDSnet; 5 million beneficiaries younger than 21 years enrolled for at least 6 months in HIRD; and 35 million Medicaid or Children's Health Insurance Program beneficiaries younger than 19 years enrolled for any amount of time in T-MSIS. Exposure: Calendar year and type of medical subspecialty. Main Outcomes and Measures: Annual number of children with at least 1 completed visit to any pediatric medical subspecialist in an outpatient setting per population. Use rates excluded visits in emergency department or inpatient settings. Results: Among the study population, the proportion of girls was 51.0% for PEDSnet, 51.1% for HIRD, and 49.3% for T-MSIS; the proportion of boys was 49.0% for PEDSnet, 48.9% for HIRD, and 50.7% for T-MSIS. The proportion of visits among children younger than 5 years was 37.4% for PEDSnet, 20.9% for HIRD, and 26.2% for T-MSIS; most patients were non-Hispanic Black (29.7% for PEDSnet and 26.1% for T-MSIS) or non-Hispanic White (44.9% for PEDSnet and 43.2% for T-MSIS). Annual rates for PEDSnet ranged from 18.0% to 21.3%, which were higher than rates for HIRD (range, 7.9%-10.4%) and T-MSIS (range, 7.6%-8.6%). Subspecialist use increased in the HIRD commercial health plans (annual relative increase of 2.4% [95% CI, 1.6%-3.1%]), but rates were essentially flat in the other data sources (PEDSnet, -0.2% [95% CI, -1.1% to 0.7%]; T-MSIS, -0.7% [95% CI, -6.5% to 5.5%]). The flat PEDSnet growth reflects a balance between annual use increases among those with commercial insurance (1.2% [95% CI, 0.3%-2.1%]) and decreases in use among those with Medicaid (-0.9% [95% CI, -1.6% to -0.2%]). Conclusions and Relevance: The findings of this cross-sectional study suggest that among children, 8.6% of Medicaid beneficiaries, 10.4% of those with commercial insurance, and 21.3% of those whose primary care is received in academic health systems use pediatric medical subspecialty care each year. There was a small increase in rates of subspecialty use among children with commercial but not Medicaid insurance. These data may help launch innovations in the primary-specialty care interface.

Incidence, Prevalence, and Racial and Ethnic Distribution of Inflammatory Bowel Disease in the United States.

BACKGROUND & AIMS: We sought to estimate the incidence, prevalence, and racial-ethnic distribution of physician-diagnosed inflammatory bowel disease (IBD) in the United States. METHODS: The study used 4 administrative claims data sets: a 20% random sample of national fee-for-service Medicare data (2007 to 2017); Medicaid data from Florida, New York, Pennsylvania, Ohio, and California (1999 to 2012); and commercial health insurance data from Anthem beneficiaries (2006 to 2018) and Optum's deidentified Clinformatics Data Mart (2000 to 2017). We used validated combinations of medical diagnoses, diagnostic procedures, and prescription medications to identify incident and prevalent diagnoses. We computed pooled age-, sex-, and race/ethnicity-specific insurance-weighted estimates and pooled estimates standardized to 2018 United States Census estimates with 95% confidence intervals (CIs). RESULTS: The age- and sex-standardized incidence of IBD per 100,000 person-years was 10.9 (95% CI, 10.6-11.2). The incidence of IBD peaked in the third decade of life, decreased to a relatively stable level across the fourth to eighth decades, and declined further. The age-, sex- and insurance-standardized prevalence of IBD was 721 per 100,000 population (95% CI, 717-726). Extrapolated to the 2020 United States Census, an estimated 2.39 million Americans are diagnosed with IBD. The prevalence of IBD per 100,000 population was 812 (95% CI, 802-823) in White, 504 (95% CI, 482-526) in Black, 403 (95% CI, 373-433) in Asian, and 458 (95% CI, 440-476) in Hispanic Americans. CONCLUSIONS: IBD is diagnosed in >0.7% of Americans. The incidence peaks in early adulthood and then plateaus at a lower rate. The disease is less commonly diagnosed in Black, Asian, and Hispanic Americans.

Comparing Patient-Reported Outcomes Among Anti-TNF Experienced Patients With Ulcerative Colitis Initiating Vedolizumab Versus Tofacitinib.

Background: Primary and secondary nonresponse to anti-tumor necrosis factor (TNF) therapy is common in patients with ulcerative colitis (UC), yet limited research has compared the effectiveness of subsequent biological therapy. Objective: We sought to compare the effectiveness of vedolizumab and tofacitinib in anti-TNF experienced patients with UC, focusing on patient-prioritized patient-reported outcomes (PROs). Methods: We conducted a prospective cohort study nested within the Crohn's & Colitis Foundation's IBD Partners and SPARC IBD initiatives. We identified anti-TNF experienced patients with UC initiating vedolizumab or tofacitinib and analyzed PROs reported approximately 6 months later (minimum 4 months, maximum 10 months). Co-primary outcomes were Patient Reported Outcome Measurement Information System (PROMIS) domains of Fatigue and Pain Interference. Secondary outcomes included PRO2, treatment persistence, and need for colectomy. Results: We compared 72 vedolizumab initiators and 33 tofacitinib initiators. At follow-up, Pain Interference (P = .04), but not Fatigue (P = .53) was lower among tofacitinib initiators. A trend toward higher Social Role Satisfaction was not significant. The remainder of secondary outcomes (PRO2, treatment persistence, colectomy) did not differ between treatment groups. Conclusions: Among anti-TNF experienced patients with UC, Pain Interference 4-10 months after treatment initiation was lower among tofacitinib users as compared with vedolizumab users. Many, but not all, secondary endpoints and subanalyses also favored tofacitinib. Future studies with larger sample sizes are needed to further evaluate these findings.

Development and Validation of Claims-Based Definitions to Identify Incident and Prevalent Inflammatory Bowel Disease in Administrative Healthcare Databases.

BACKGROUND: To facilitate inflammatory bowel disease (IBD) research in the United States, we developed and validated claims-based definitions to identify incident and prevalent IBD diagnoses using administrative healthcare claims data among multiple payers. METHODS: We used data from Medicare, Medicaid, and the HealthCore Integrated Research Database (Anthem commercial and Medicare Advantage claims). The gold standard for validation was review of medical records. We evaluated 1 incidence and 4 prevalence algorithms based on a combination of International Classification of Diseases codes, National Drug Codes, and Current Procedural Terminology codes. The claims-based incident diagnosis date needed to be within ±90 days of that recorded in the medical record to be valid. RESULTS: We reviewed 111 charts of patients with a potentially incident diagnosis. The positive predictive value (PPV) of the claims algorithm was 91% (95% confidence interval [CI], 81%-97%). We reviewed 332 charts to validate prevalent case definition algorithms. The PPV was 94% (95% CI, 86%-98%) for ≥2 IBD diagnoses and presence of prescriptions for IBD medications, 92% (95% CI, 85%-97%) for ≥2 diagnoses without any medications, 78% (95% CI, 67%-87%) for a single diagnosis and presence of an IBD medication, and 35% (95% CI, 25%-46%) for 1 physician diagnosis and no IBD medications. CONCLUSIONS: Through a combination of diagnosis, procedural, and medication codes in insurance claims data, we were able to identify incident and prevalent IBD cases with high accuracy. These algorithms can be useful for the ascertainment of IBD cases in future studies.

Childhood asthma diagnoses declined during the COVID-19 pandemic in the United States.

BACKGROUND: Prior studies have documented declines in pediatric asthma exacerbations and asthma-related health care utilization during the COVID-19 pandemic, but less is known about the incidence of asthma during the pandemic. METHODS: We conducted a retrospective cohort study of children under age 18 without a prior diagnosis of asthma within a large US commercial claims database. Incident asthma was defined using a combination of diagnosis codes, location of services, and medication dispensing. Crude quarterly rates of asthma diagnosis per 1000 children were calculated, and the incidence rate ratio and 95% confidence interval were estimated for newly diagnosed asthma during versus before the pandemic using negative binomial regression, adjusted for age, sex, region, and season. RESULTS: Compared with 3 years prior to the pandemic, crude incident diagnosis rates of asthma decreased by 52% across the first four quarters of the US pandemic. The covariate-adjusted pandemic-associated incidence rate ratio was 0.47 (95% confidence interval 0.43, 0.51). CONCLUSIONS: New diagnoses of childhood asthma in the US declined by half during the first year of the pandemic. These findings raise important questions whether pandemic-related changes in infectious or other triggers truly altered the incidence of childhood asthma beyond the well-described disruptions in healthcare access.

Real-World Evidence Comparing Vedolizumab and Ustekinumab in Antitumor Necrosis Factor-Experienced Patients With Crohn's Disease.

INTRODUCTION: Many patients with Crohn's disease (CD) lose response or become intolerant to antitumor necrosis factor (TNF) therapy and subsequently switch out of class. We compared the effectiveness and safety of ustekinumab to vedolizumab in a large, geographically diverse US population of TNF-experienced patients with CD. METHODS: We conducted a retrospective cohort study using longitudinal claims data from a large US insurer (Anthem, Inc.). We identified patients with CD initiating vedolizumab or ustekinumab with anti-TNF treatment in the prior 6 months. Our primary outcome was treatment persistence for >52 weeks. Secondary outcomes included (i) all-cause hospitalization, (ii) hospitalization for CD with surgery, (iii) hospitalization for CD without surgery, and (iv) hospitalization for infection. Propensity score fine stratification was used to control for demographic and baseline clinical characteristics and prior treatments. RESULTS: Among 885 new users of ustekinumab and 490 new users of vedolizumab, we observed no difference in treatment persistence (adjusted risk ratio 1.09 [95% confidence interval 0.95-1.25]). Ustekinumab was associated with a lower rate of all-cause hospitalization (adjusted hazard ratio 0.73 [0.59-0.91]), nonsurgical CD hospitalization (adjusted hazard ratio 0.58 [0.40-0.83]), and hospitalization for infection (adjusted hazard ratio 0.56 [0.34-0.92]). DISCUSSION: This real-world comparative effectiveness study of anti-TNF-experienced patients with CD initiating vedolizumab or ustekinumab showed similar treatment persistence rates beyond 52 weeks, although secondary outcomes such as all-cause hospitalizations, nonsurgical CD hospitalizations, and hospitalizations for infection favored ustekinumab initiation. We, therefore, advocate for individualized decision making in this medically refractory population, considering patient preference and other factors such as cost and route of administration.

Validity of ICD-10-CM diagnoses to identify hospitalizations for serious infections among patients treated with biologic therapies.

PURPOSE: Identifying hospitalizations for serious infections among patients dispensed biologic therapies within healthcare databases is important for post-marketing surveillance of these drugs. We determined the positive predictive value (PPV) of an ICD-10-CM-based diagnostic coding algorithm to identify hospitalization for serious infection among patients dispensed biologic therapy within the FDA's Sentinel Distributed Database. METHODS: We identified health plan members who met the following algorithm criteria: (1) hospital ICD-10-CM discharge diagnosis of serious infection between July 1, 2016 and August 31, 2018; (2) either outpatient/emergency department infection diagnosis or outpatient antimicrobial treatment within 7 days prior to hospitalization; (3) inflammatory bowel disease, psoriasis, or rheumatological diagnosis within 1 year prior to hospitalization, and (4) were dispensed outpatient biologic therapy within 90 days prior to admission. Medical records were reviewed by infectious disease clinicians to adjudicate hospitalizations for serious infection. The PPV (95% confidence interval [CI]) for confirmed events was determined after further weighting by the prevalence of the type of serious infection in the database. RESULTS: Among 223 selected health plan members who met the algorithm, 209 (93.7% [95% CI, 90.1%-96.9%]) were confirmed to have a hospitalization for serious infection. After weighting by the prevalence of the type of serious infection, the PPV of the ICD-10-CM algorithm identifying a hospitalization for serious infection was 80.2% (95% CI, 75.3%-84.7%). CONCLUSIONS: The ICD-10-CM-based algorithm for hospitalization for serious infection among patients dispensed biologic therapies within the Sentinel Distributed Database had 80% PPV for confirmed events and could be considered for use within pharmacoepidemiologic studies.

Testosterone Therapy in Relation to Prostate Cancer in a U.S. Commercial Insurance Claims Database.

BACKGROUND: We conducted a study to assess whether testosterone therapy (TT) alters prostate cancer risk using a large U.S. commercial insurance research database. METHODS: From the HealthCore Integrated Research Database (HIRD), we selected men ages 30 years or greater who were new users of TT during 2007 to 2015. We selected two comparison groups: (i) unexposed (matched 10:1) and (ii) new users of phosphodiesterase type 5 inhibitor (PDE5i). Incident prostate cancer was defined as diagnosis of prostate cancer within 4 weeks following prostate biopsy. Propensity scores and inverse probability of treatment weights were used in Poisson regression models to estimate adjusted incidence rates, incidence rate ratios (IRR), and 95% confidence intervals (CI). Subgroup analyses included stratification by prostate cancer screening, hypogonadism, and follow-up time. RESULTS: The adjusted prostate cancer IRR was 0.77 (95% CI, 0.68-0.86) when comparing TT with the unexposed group and 0.85 (95% CI, 0.79-0.91) in comparison with the PDE5i group. Inverse associations between TT and prostate cancer were observed in a majority of subgroup analyses, although in both comparisons estimates generally attenuated with increasing time following initial exposure. Among TT users, duration of exposure was not associated with prostate cancer. CONCLUSIONS: Men who received TT did not have a higher rate of prostate cancer compared with the unexposed or PDE5i comparison groups. The inverse association between TT and prostate cancer could be the result of residual confounding, contraindication bias, or undefined biological effect. IMPACT: This study suggests that limited TT exposure does not increase risk of prostate cancer in the short term.

Validation of an Algorithm for Claims-based Incidence of Prostate Cancer.

BACKGROUND: Prostate cancer is a commonly studied outcome in administrative claims studies, but there is a dearth of validated case identifying algorithms. The long-term development of the disease increases the difficulty in separating prevalent from incident prostate cancer. The purpose of this validation study was to assess the accuracy of a claims algorithm to identify incident prostate cancer among men in commercial and Medicare Advantage US health plans. METHODS: We identified prostate cancer in claims as a prostate cancer diagnosis within 28 days after a prostate biopsy and compared case ascertainment in the claims with the gold standard results from the Georgia Comprehensive Cancer Registry (GCCR). RESULTS: We identified 74,008 men from a large health plan claims database for possible linkage with GCCR. Among the 382 prostate cancer cases identified in claims, 312 were also identified in the GCCR (positive predictive value [PPV] = 82%). Of the registry cases, 91% (95% confidence interval = 88, 94) were correctly identified in claims. Claims and registry diagnosis dates of prostate cancer matched exactly in 254/312 (81%) cases. Nearly half of the false-positive cases also had claims for prostate cancer treatment. Thirteen (43%) false-negative cases were classified as noncases by virtue of having a biopsy and diagnosis >28 days apart as required by the algorithm. Compared to matches, false-negative cases were older men with less aggressive prostate cancer. CONCLUSIONS: Our algorithm demonstrated a PPV of 82% with 92% sensitivity in ascertaining incident PC. Administrative health plan claims can be a valuable and accurate source to identify incident prostate cancer cases.

Prenatal Stress as a Modifier of Associations between Phthalate Exposure and Reproductive Development: results from a Multicentre Pregnancy Cohort Study.

BACKGROUND: Prenatal phthalate exposure is associated with altered male reproductive tract development, and in particular, shorter anogenital distance (AGD). AGD, a sexually dimorphic index of prenatal androgen exposure, may also be altered by prenatal stress. How these exposures interact to impact AGD is unknown. Here, we examine the extent to which associations between prenatal phthalate exposure and infant AGD are modified by prenatal exposure to stressful life events (SLEs). METHODS: Phthalate metabolites [including those of diethylhexyl phthalate (DEHP) and their molar sum (ΣDEHP)] were measured in first trimester urine from 738 pregnant women participating in The Infant Development and the Environment Study (TIDES). Women completed questionnaires on SLEs, and permitted infant AGD measurements at birth. Subjects were classified as 'lower' and 'higher' stress (0 first trimester SLEs vs. 1+).We estimated relationships between phthalate concentrations and AGD (by infant sex and stress group) using adjusted multiple regression interaction models. RESULTS: In the lower stress group, first trimester ΣDEHP was inversely associated with two measures of male AGD: anoscrotal distance (AGD-AS; ß = -1.78; 95% CI -2.97, -0.59) and anopenile distance (AGD-AP; ß = -1.61; 95% CI -3.01, -0.22). By contrast, associations in the higher stress group were mostly positive and non-significant in male infants. No associations were observed in girls. CONCLUSIONS: Associations between prenatal phthalate exposure and altered genital development were only apparent in sons of mothers who reported no SLEs during pregnancy. Prenatal stress and phthalates may interact to shape fetal development in ways that have not been previously explored.

Environmental exposure to di-2-ethylhexyl phthalate is associated with low interest in sexual activity in premenopausal women.

Phthalates, a ubiquitous class of environmental chemicals, may interfere with typical reproductive hormone production both in utero and in adulthood. Although they are best known as anti-androgens, increasingly, evidence suggests that phthalates, particularly di-2-ethylhexyl phthalate (DEHP), may also suppress estrogen production. Given that both androgens and estrogens are essential for sexual function, particularly sexual interest, it is plausible that adult exposure to phthalates alters sexual function. To this end, we used data from 360 women participating in a pregnancy cohort study (the Study for Future Families) to examine whether urinary phthalate metabolite concentrations were associated with two dimensions of self-reported sexual dysfunction in the months prior to conception: lack of sexual interest and vaginal dryness. Women in the highest quartile of urinary concentrations of mono-2-ethyl-5-hydroxyhexyl phthalate, a DEHP metabolite, had 2.58 (95% CI 1.33, 5.00) times the adjusted odds of reporting that they almost always or often lacked interest in sexual activity, and results were similar for mono-2-ethyl-5-oxohexyl phthalate (aOR: 2.56, 95% CI 1.32, 4.95), another DEHP metabolite. Self-reported vaginal dryness was not associated with any phthalate metabolite concentration. This study is novel in its focus on sexual function in relation to environmentally relevant (rather than occupational) exposure to phthalates in adult women and these preliminary findings merit replication in a large, prospective study. Better understanding how adult exposure to phthalates may affect reproductive health, including sexual function, is of public health interest given that virtually all Westerners are exposed to phthalates.

Differences in ovarian hormones in relation to parity and time since last birth.

OBJECTIVE: To examine ovarian function in relation to parity and time since last birth. DESIGN: Cross-sectional study. SETTING: Health-care program in California. PATIENT(S): 346 naturally cycling women, aged 18 to 39 years. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Mean follicular urinary estradiol metabolite concentration (E1C) (cycle days -8 to -1), mean luteal progesterone metabolite concentration (PdG) (days 0 to +10), and cycle phase lengths in ovulatory cycles. RESULT(S): After the women had collected daily urine samples for up to eight menstrual cycles, we measured the E1C and PdG using enzyme-linked immunoassay. The cycle phase lengths were calculated from the hormone profiles and daily diaries. Women who had given birth within the previous 3 years had lower E1C than the nulliparous women and women who last given birth >3 years earlier. Among the parous women, E1C was positively associated with the time since last birth. Women who last gave birth >3 years earlier had longer follicular phases than the nulliparous women. There were no associations between parity and PdG or luteal phase length. CONCLUSION(S): Our cross-sectional data suggest that ovarian function differs in nulliparous and parous women and is positively associated with the time since last birth. Longitudinal research is needed to explore within-woman changes in ovarian function prepartum and postpartum.

Evidence for sexually dimorphic associations between maternal characteristics and anogenital distance, a marker of reproductive development.

Data from animal models, historical cohorts, and modern epidemiologic studies have suggested that maternal characteristics can affect reproductive health of offspring; however, distinguishing between prenatal and postnatal contributions is difficult. Anogenital distance (AGD), the distance from the anus to the genitals, is believed to be a biomarker of prenatal androgen exposure in many species, and in humans it has been associated with several adult reproductive health outcomes. We used data from a pregnancy cohort study conducted in 4 US cities from 1999-2005 to examine whether AGD measurements in infants were associated with maternal self-reported age at conception, age at menarche, age at first birth, parity, and gravidity. AGD was measured in 289 infants (140 male, 149 female) born to study participants. After adjustment for relevant covariates, in linear regression models stratified by infant sex, maternal age was positively associated with AGD in male infants (AGD, anus to penis: ß = 0.50, P = 0.002; AGD, anus to scrotum: ß = 0.29, P = 0.02) but not female infants. Parity was inversely associated with AGD (anus to scrotum; ß = -1.68, P = 0.03) in male infants. No other maternal characteristic predicted AGD in either sex. The mechanism underlying the unexpected relationship between maternal characteristics and AGD is unknown; however, we suggest several possibilities for future study.

Prenatal exposure to stressful life events is associated with masculinized anogenital distance (AGD) in female infants.

In animal models, prenatal stress programs reproductive development in the resulting offspring, however little is known about effects in humans. Anogenital distance (AGD) is a commonly used, sexually dimorphic biomarker of prenatal androgen exposure in many species. In rodents, prenatally stressed males have shorter AGD than controls (suggesting lower prenatal androgen exposure), whereas prenatally stressed females have longer AGD than controls (suggesting greater prenatal androgen exposure). Our objective was to investigate the relationship between stressful life events in pregnancy and infant AGD. In a prospective cohort study, pregnant women and their partners reported exposure to stressful life events during pregnancy. Pregnancies in which the couple reported 4+ life events were considered highly stressed. After birth (average 16.5 months), trained examiners measured AGD in the infants (137 males, 136 females). After adjusting for age, body size and other covariates, females born to couples reporting high stress had significantly longer (i.e. more masculine) AGD than females born to couples reporting low stress (p=0.015). Among males, high stress was weakly, but not significantly, associated with shorter AGD. Our results suggest prenatal stress may masculinize some aspects of female reproductive development in humans. More sensitive measures of prenatal stress and additional measures of reproductive development are needed to better understand these relationships and clarify mechanisms.

Women's exposure to phthalates in relation to use of personal care products.

Several phthalates, particularly diethyl phthalate (DEP) and di-n-butyl phthalate, can be used in personal care products (PCPs) to fix fragrance and hold color. We investigated associations between women's reported use of PCPs within the 24 h before urine collection and concentrations of several urinary phthalate metabolites. Between 2002 and 2005, 337 women provided spot urine samples and answered questions regarding their use of 13 PCPs at a follow-up visit 3-36 months after pregnancy. We examined associations between urinary concentrations of several phthalate metabolites and use of PCPs using linear regression. Use of individual PCPs ranged from 7% (nail polish) to 91% (deodorant). After adjusting for age, education, and urinary creatinine, women reporting use of perfume had 2.92 times higher (95% CI: 2.20-3.89) concentration of monoethyl phthalate (MEP; the primary metabolite of DEP) than other women. Other PCPs that were significantly associated with MEP concentrations included: hair spray, nail polish, and deodorant. MEP concentrations increased with the number of PCPs used. PCP use was widespread in this group of recently pregnant women. Women's use of PCPs, particularly of perfumes and fragranced products, was positively associated with urinary concentration of multiple phthalate metabolites.

Socioeconomic factors and phthalate metabolite concentrations among United States women of reproductive age.

INTRODUCTION: Relatively little is known about the socioeconomic correlates of phthalate metabolite urine concentrations among the general population, exposures of increasing public health concern, particularly for women of reproductive age. METHODS: We pooled data from the 2001-2008 cycles of the National Health and Nutrition Examination Survey to examine the associations between phthalate metabolite concentrations (including the molar sum of four di-2-ethylhexyl phthalate (DEHP) metabolites, the molar sum of two dibutyl phthalate (DBP) metabolites, and metabolites of benzylbutyl phthalate (BzBP) and diethyl phthalate (DEP)) with socioeconomic indicators (including ethnicity, education, income, and food security status) among women 20 to 39 years age. We also derived a socioeconomic status summary measure using factor analysis and investigated its associations with metabolite concentrations. RESULTS: In fully adjusted models, the lowest quartile of overall socioeconomic status was associated with 1.83 (95% CI=1.54-2.17) times the concentrations of mono-benzyl phthalate (MBzP), and 0.72 (95% CI=0.54-0.98) times the concentrations of (molar sum) DEHP metabolites compared with the highest quartile of overall socioeconomic status. This latter association was driven primarily by educational attainment. All Non-White ethnicities combined had 1.24 (95% CI=1.09-1.40) times the concentrations of (molar sum) DBP metabolites, 1.32 (95% CI=1.12-1.56) times the mono-ethyl phthalate (MEP) concentrations, and 0.82 (95% CI=0.71-0.96) the concentrations of MBzP of Non-Hispanic Whites. CONCLUSIONS: Biomarkers of phthalate exposure vary with socioeconomic factors in women of reproductive age in the United States. Given the public health concern surrounding phthalate exposure, more research is needed to elucidate the reasons for these differences.

Evaluation of occupational exposure to magnetic fields and motor neuron disease mortality in a population-based cohort.

OBJECTIVE: Epidemiologic evidence for the association between electromagnetic fields and amyotrophic lateral sclerosis, the most common form of motor neuron disease (MND), has been inconclusive. We evaluated the association between electromagnetic fields and MND among workers in occupations potentially exposed to magnetic fields METHODS: MND mortality (ICD-9 335.2) was examined in the National Longitudinal Mortality Study using multivariable proportional hazards models. Occupational exposure to magnetic fields was determined on the basis of a population-based job-exposure matrix. Age at entry, education, race, sex, and income were considered for inclusion as covariates RESULTS: After adjusting for age, sex, and education, there were no increased risks of MND mortality in relation to potential magnetic field exposure, with hazard ratios around the null in all magnetic field exposure quartiles CONCLUSIONS: Our study does not provide evidence for an association between magnetic field exposure and MND mortality.