Simon J Hambidge

Kaiser Permanente, Oakland, California, United States

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Publications (92)442.15 Total impact

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    ABSTRACT: Although Colorado is perceived as a healthy state, in 2010, 14.1 % of children aged 2-5 were overweight and 9.1 % were obese. Despite the high prevalence of obesity in this population, evidence to support particular strategies to treat obese preschoolers is lacking. The efficacy of home-based, childhood obesity interventions to reduce a child's body mass index is inconclusive. However, this model uniquely provides an opportunity to observe and intervene with the home food and activity environment and engage the entire family in promoting changes that fit each family's unique dynamics. Eligible participants are children aged 2-5 years who attended a well-child care visit at a Denver Health Community Health Service clinic within 12 months prior to recruitment and on that visit had a body mass index (BMI) >85th percentile-for-age. Participants are randomly recruited at study inception and allocated to the intervention in one of five defined 6-month stepped wedge engagements; the delayed intervention groups serves as control groups until the start of the intervention. The program is delivered by a patient navigator at the family' home and consists of a 16-session curriculum focused on 1) parenting styles, 2) nutrition, and 3) physical activity. At each visit, a portion of curriculum is delivered to guide parents and children in selecting one goal for behavior change in each of three work areas to work on during the following week. The primary study outcome measure is change in BMI z-score from baseline to post-intervention period. This childhood obesity study, innovative for its home-based intervention venue, provides rich data characterizing barriers and facilitators to healthy behavior change within the home. The study population is innovative as it is focused on preschool-aged, Latino children from low-income families; this population has not typically been targeted in obesity management assessments. The home-based intervention is linked to clinical care through update letters and assessment of the program's impact to the child's medical providers. Informing primary care providers about a child's accomplishments and challenges, allows the clinician to support the health weight effort when seeing families during subsequent clinical visits. NCT02024360 Registered December 21, 2013.
    BMC Public Health 12/2015; 15(1). DOI:10.1186/s12889-015-1833-z · 2.26 Impact Factor
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    ABSTRACT: Introduction: Pregnant women are at risk for influenza-related complications and have been recommended for vaccination by the Advisory Committee on Immunization Practices (ACIP) since 1990. Annual rates of influenza coverage of pregnant women have been consistently low. The Vaccine Safety Datalink was used to assess influenza vaccine coverage over 10 consecutive years (2002-2012); assess patterns related to changes in ACIP recommendations; identify predictors of vaccination; and compare the results with those published by national U.S. surveys. Methods: Retrospective cohort study of 721,898 pregnancies conducted in 2014. Coverage rates were assessed for all pregnancies and for live births only. Multivariate regression analysis identified predictors associated with vaccination. Results: Coverage increased from 8.8% to 50.9% in 2002-2012. Seasonal coverage rates increased slowly following the 2004 ACIP influenza vaccine recommendation (to remove the first trimester restriction), but spiked significantly during the 2009 H1N1 influenza pandemic. Significant predictors of vaccination during pregnancy included older age; vaccination in a previous season; high-risk conditions in addition to pregnancy; pregnancy during either the 2004-2005 or 2009-2010 seasons; entering the influenza season after the first trimester of pregnancy; and a pregnancy with longer overlap with the influenza season (p<0.001 for each). Conclusions: Influenza vaccination coverage among pregnant women increased between the 2002-2003 and 2011-2012 seasons, although it was still below the developmental Healthy People 2020 goal of 80%. The 2004 ACIP language change positively impacted first-trimester vaccination uptake. Vaccine Safety Datalink data estimates were consistent with U.S. estimates.
    American journal of preventive medicine 11/2015; DOI:10.1016/j.amepre.2015.08.017 · 4.53 Impact Factor

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    ABSTRACT: Importance: The Advisory Committee on Immunization Practices (ACIP) recommends the tetanus, diphtheria, and acellular pertussis (Tdap) vaccine for pregnant women during each pregnancy, regardless of prior immunization status. However, safety data on repeated Tdap vaccination in pregnancy is lacking. Objective: To determine whether receipt of Tdap vaccine during pregnancy administered in close intervals from prior tetanus-containing vaccinations is associated with acute adverse events in mothers and adverse birth outcomes in neonates. Design, setting, and participants: A retrospective cohort study in 29 155 pregnant women aged 14 through 49 years from January 1, 2007, through November 15, 2013, using data from 7 Vaccine Safety Datalink sites in California, Colorado, Minnesota, Oregon, Washington, and Wisconsin. Exposures: Women who received Tdap in pregnancy following a prior tetanus-containing vaccine less than 2 years before, 2 to 5 years before, and more than 5 years before. Main outcomes and measures: Acute adverse events (fever, allergy, and local reactions) and adverse birth outcomes (small for gestational age, preterm delivery, and low birth weight) were evaluated. Women who were vaccinated with Tdap in pregnancy and had a prior tetanus-containing vaccine more than 5 years before served as controls. Results: There were no statistically significant differences in rates of medically attended acute adverse events or adverse birth outcomes related to timing since prior tetanus-containing vaccination. For example, local reactions occurred at a rate (per 10 000 women) of 4.2 in those who received Tdap in pregnancy less than 2 years before (adjusted risk ratio [RR], 0.49 [95% CI, 0.11-2.20]; P = .35) and 7.0 two to 5 years before (adjusted RR, 0.77 [95% CI, 0.31-1.95]; P = .59) a prior tetanus-containing vaccine compared with 11.2 in controls. Preterm delivery occurred in 6.6% of women receiving Tdap in pregnancy less than 2 years before (adjusted RR, 1.15 [95% CI, 0.98-1.34]; P = .08) and 6.4% two to 5 years before (adjusted RR, 1.06 [95% CI, 0.94-1.19]; P = .33) a prior tetanus-containing vaccine compared with 6.8% of controls. Small for gestational age delivery occurred in 9.0% of women less than 2 years before (adjusted RR, 0.99 [95% CI, 0.87-1.13]; P = .88) and 8.7% of women 2 to 5 years before (adjusted RR, 0.96 [95% CI, 0.87-1.06]; P = .45) a prior tetanus-containing vaccine compared with 9.1% of controls. Conclusions and relevance: Among women who received Tdap vaccination during pregnancy, there was no increased risk of acute adverse events or adverse birth outcomes for those who had been previously vaccinated less than 2 years before or 2 to 5 years before compared with those who had been vaccinated more than 5 years before. These findings suggest that relatively recent receipt of a prior tetanus-containing vaccination does not increase risk after Tdap vaccination in pregnancy.
    JAMA The Journal of the American Medical Association 10/2015; 314(15):1581-1587. DOI:10.1001/jama.2015.12790 · 35.29 Impact Factor
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    ABSTRACT: Background: Anaphylaxis is a potentially life-threatening allergic reaction. The risk of anaphylaxis after vaccination has not been well described in adults or with newer vaccines in children. Objective: We sought to estimate the incidence of anaphylaxis after vaccines and describe the demographic and clinical characteristics of confirmed cases of anaphylaxis. Methods: Using health care data from the Vaccine Safety Datalink, we determined rates of anaphylaxis after vaccination in children and adults. We first identified all patients with a vaccination record from January 2009 through December 2011 and used diagnostic and procedure codes to identify potential anaphylaxis cases. Medical records of potential cases were reviewed. Confirmed cases met the Brighton Collaboration definition for anaphylaxis and had to be determined to be vaccine triggered. We calculated the incidence of anaphylaxis after all vaccines combined and for selected individual vaccines. Results: We identified 33 confirmed vaccine-triggered anaphylaxis cases that occurred after 25,173,965 vaccine doses. The rate of anaphylaxis was 1.31 (95% CI, 0.90-1.84) per million vaccine doses. The incidence did not vary significantly by age, and there was a nonsignificant female predominance. Vaccine-specific rates included 1.35 (95% CI, 0.65-2.47) per million doses for inactivated trivalent influenza vaccine (10 cases, 7,434,628 doses given alone) and 1.83 (95% CI, 0.22-6.63) per million doses for inactivated monovalent influenza vaccine (2 cases, 1,090,279 doses given alone). The onset of symptoms among cases was within 30 minutes (8 cases), 30 to less than 120 minutes (8 cases), 2 to less than 4 hours (10 cases), 4 to 8 hours (2 cases), the next day (1 case), and not documented (4 cases). Conclusion: Anaphylaxis after vaccination is rare in all age groups. Despite its rarity, anaphylaxis is a potentially life-threatening medical emergency that vaccine providers need to be prepared to treat.
    The Journal of allergy and clinical immunology 10/2015; DOI:10.1016/j.jaci.2015.07.048 · 11.48 Impact Factor
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    ABSTRACT: Objective: To evaluate the safety of coadministering tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) and influenza vaccines during pregnancy by comparing adverse events after concomitant and sequential vaccination. Methods: We conducted a retrospective cohort study of pregnant women aged 14-49 years in the Vaccine Safety Datalink from January 1, 2007, to November 15, 2013. We compared medically attended acute events (fever, any acute reaction) and adverse birth outcomes (preterm delivery, low birth weight, small for gestational age) in women receiving concomitant Tdap and influenza vaccination and women receiving sequential vaccination. Results: Among 36,844 pregnancies in which Tdap and influenza vaccines were administered, the vaccines were administered concomitantly in 8,464 (23%) pregnancies and sequentially in 28,380 (77%) pregnancies. Acute adverse events after vaccination were rare. We found no statistically significant increased risk of fever or any medically attended acute adverse event in pregnant women vaccinated concomitantly compared with sequentially. When analyzing women at 20 weeks of gestation or greater during periods of influenza vaccine administration, there were no differences in preterm delivery, low-birth-weight, or small-for-gestational-age neonates between women vaccinated concomitantly compared with sequentially in pregnancy. Conclusion: Concomitant administration of Tdap and influenza vaccines during pregnancy was not associated with a higher risk of medically attended adverse acute outcomes or birth outcomes compared with sequential vaccination. Level of evidence: II.
    Obstetrics and Gynecology 10/2015; DOI:10.1097/AOG.0000000000001066 · 5.18 Impact Factor
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    ABSTRACT: The Vaccine Safety Datalink (VSD) is a collaboration between CDC and nine integrated health care systems that serve as a cornerstone of US post-licensure vaccine safety monitoring. Given concerns that potential differences between the insured VSD population and the US population could limit the generalizability of VSD study findings, we performed a comparison of the demographic characteristics between the two populations. We collected data from medical records and administrative files at VSD sites in 2010 to compare sex, age, race, ethnicity, income, and educational attainment to the 2010 US census population. We also compared data on the 2012 VSD Medicaid population to 2012 US Medicaid data. The VSD population included over eight million individuals in 2010, which represented 2.6% of the total US population. All major demographic groups were represented in the VSD. We found no major differences in comparing sex, race, ethnicity, and educational attainment between the VSD and the US population. Middle income populations were comparable between the VSD and the US. While the percentage of lower income populations was less in the VSD compared to the US, the VSD had over two million individuals in this group. Additionally, there were over 600,000 Medicaid members in the VSD in 2012, which represented 1.1% of the US Medicaid population. We found that the VSD population is representative of the general US population on several key demographic and socioeconomic variables. Despite a few specific groups being underrepresented in the VSD compared to the US, the absolute number of VSD members is large enough to ensure significant representation of these groups in vaccine safety studies that use VSD data. Copyright © 2015. Published by Elsevier Ltd.
    Vaccine 07/2015; 33(36). DOI:10.1016/j.vaccine.2015.07.037 · 3.62 Impact Factor
  • Richard E Boles · Lourdes Yun · Simon J Hambidge · Arthur Davidson ·

    Clinical Pediatrics 02/2015; DOI:10.1177/0009922815570614 · 1.15 Impact Factor
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    ABSTRACT: All measles-containing vaccines are associated with several types of adverse events, including seizure, fever, and immune thrombocytopenia purpura (ITP). Because the measles-mumps-rubella-varicella (MMRV) vaccine compared with the separate measles-mumps-rubella (MMR) and varicella (MMR + V) vaccine increases a toddler's risk for febrile seizures, we investigated whether MMRV is riskier than MMR + V and whether either vaccine elevates the risk for additional safety outcomes. Study children were aged 12 to 23 months in the Vaccine Safety Datalink from 2000 to 2012. Nine study outcomes were investigated: 7 main outcomes (anaphylaxis, ITP, ataxia, arthritis, meningitis/encephalitis, acute disseminated encephalomyelitis, and Kawasaki disease), seizure, and fever. Comparing MMRV with MMR + V, relative risk was estimated by using stratified exact binomial tests. Secondary analyses examined post-MMRV or MMR + V risk versus comparison intervals; risk and comparison intervals were then contrasted for MMRV versus MMR+V. We evaluated 123 200 MMRV and 584 987 MMR + V doses. Comparing MMRV with MMR + V, risks for the 7 main outcomes were not significantly different. Several outcomes had few or zero postvaccination events. Comparing risk versus comparison intervals, ITP risk was higher after MMRV (odds ratio [OR]: 11.3 [95% confidence interval (CI): 1.9 to 68.2]) and MMR + V (OR: 10 [95% CI: 4.5 to 22.5]) and ataxia risk was lower after both vaccines (MMRV OR: 0.8 [95% CI: 0.5 to 1]; MMR + V OR: 0.8 [95% CI: 0.7 to 0.9]). Compared with MMR + V, MMRV increased risk of seizure and fever 7 to 10 days after vaccination. This study did not identify any new safety concerns comparing MMRV with MMR + V or after either the MMRV or the MMR + V vaccine. This study provides reassurance that these outcomes are unlikely after either vaccine. Copyright © 2015 by the American Academy of Pediatrics.
    Pediatrics 01/2015; 135(2). DOI:10.1542/peds.2014-1822 · 5.47 Impact Factor
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    ABSTRACT: To identify which English and Spanish terms Latino parents consider motivating, as well as culturally and linguistically appropriate, for provider use during weight counseling of overweight and obese Latino youth. Latino parent perceptions of common Spanish and English terms for overweight were discussed with 54 parents in 6 focus groups (3 English, 3 Spanish). Atlas.ti software was used for qualitative analysis. An initial codebook was used to code passages for English and Spanish terminology separately. Subsequent changes to the coded passages and creation of new codes were made by team consensus. "Demasiado peso para su salud" (too much weight for his/her health) was the only phrase for excess weight that was consistently identified as motivating and inoffensive by Spanish-speaking parents. "Sobrepeso" (overweight), a commonly used term among health care providers, was motivating to some parents but offensive to others. English-speaking parents had mixed reactions to "unhealthy weight," "weight problem," and "overweight," finding them motivating, confusing, or insulting. Parents found "fat" "gordo" and "obese" "obeso" consistently offensive. Most participants found growth charts and the term "BMI" confusing. Parents consistently reported that providers could enhance motivation and avoid offending families by linking a child's weight to health risks, particularly diabetes. "Demasiado peso para su salud" (too much weight for his/her health) was motivating to many Spanish-speaking Latino parents. Among English-speaking Latino parents, no single English term emerged as motivating, well-understood, and inoffensive. Linking a child's excess weight with increased health risks was motivating and valuable to many parents regardless of language spoken. Copyright © 2014 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.
    Academic Pediatrics 12/2014; 15(2). DOI:10.1016/j.acap.2014.11.003 · 2.01 Impact Factor
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    ABSTRACT: Importance In 2010, due to a pertussis outbreak and neonatal deaths, the California Department of Health recommended that the tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine (Tdap) be administered during pregnancy. Tdap is now recommended by the Advisory Committee on Immunization Practices for all pregnant women, preferably between 27 and 36 weeks’ gestation. Limited data exist on Tdap safety during pregnancy.Objective To evaluate whether maternal Tdap vaccination during pregnancy is associated with increased risks of adverse obstetric events or adverse birth outcomes.Design and Setting Retrospective, observational cohort study using administrative health care databases from 2 California Vaccine Safety Datalink sites.Participants and Exposures Of 123 494 women with singleton pregnancies ending in a live birth between January 1, 2010, and November 15, 2012, 26 229 (21%) received Tdap during pregnancy and 97 265 did not.Main Outcomes and Measures Risks of small-for-gestational-age (SGA) births (<10th percentile), chorioamnionitis, preterm birth (<37 weeks’ gestation), and hypertensive disorders of pregnancy were evaluated. Relative risk (RR) estimates were adjusted for site, receipt of another vaccine during pregnancy, and propensity to receive Tdap during pregnancy. Cox regression was used for preterm delivery, and Poisson regression for other outcomes.Results Vaccination was not associated with increased risks of adverse birth outcomes: crude estimates for preterm delivery were 6.3% of vaccinated and 7.8% of unvaccinated women (adjusted RR, 1.03; 95% CI, 0.97-1.09); 8.4% of vaccinated and 8.3% of unvaccinated had an SGA birth (adjusted RR, 1.00; 95% CI, 0.96-1.06). Receipt of Tdap before 20 weeks was not associated with hypertensive disorder of pregnancy (adjusted RR, 1.09; 95% CI, 0.99-1.20); chorioamnionitis was diagnosed in 6.1% of vaccinated and 5.5% of unvaccinated women (adjusted RR, 1.19; 95% CI, 1.13-1.26).Conclusions and Relevance In this cohort of women with singleton pregnancies that ended in live birth, receipt of Tdap during pregnancy was not associated with increased risk of hypertensive disorders of pregnancy or preterm or SGA birth, although a small but statistically significant increased risk of chorioamnionitis diagnosis was observed.
    JAMA The Journal of the American Medical Association 11/2014; 312(18):1897-904. DOI:10.1001/jama.2014.14825 · 35.29 Impact Factor
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    ABSTRACT: Kawasaki disease is a childhood vascular disorder of unknown etiology. Concerns have been raised about vaccinations being a potential risk factor for Kawasaki disease. Data from the Vaccine Safety Datalink were collected on children aged 0-6 years at seven managed care organizations across the United States. Defining exposure as one of several time periods up to 42 days after vaccination, we conducted Poisson regressions controlling for age, sex, season, and managed care organization to determine if rates of physician-diagnosed and verified Kawasaki disease were elevated following vaccination compared to rates during all unexposed periods. We also performed case-crossover analyses to control for unmeasured confounding. A total of 1,721,186 children aged 0-6 years from seven managed care organizations were followed for a combined 4,417,766 person-years. The rate of verified Kawasaki disease was significantly lower during the 1-42 days after vaccination (rate ratio=0.50, 95% CL=0.27-0.92) and 8-42 days after vaccination (rate ratio=0.45, 95% CL=0.22-0.90) compared to rates during unexposed periods. Breaking down the analysis by vaccination category did not identify a subset of vaccines which was solely responsible for this association. The case-crossover analyses revealed that children with Kawasaki disease had lower rates of vaccination in the 42 days prior to symptom onset for both physician-diagnosed Kawasaki disease (rate ratio=0.79, 95% CL=0.64-0.97) and verified Kawasaki disease (rate ratio=0.38, 95% CL=0.20-0.75). Childhood vaccinations' studied did not increase the risk of Kawasaki disease; conversely, vaccination was associated with a transient decrease in Kawasaki disease incidence. Verifying and understanding this potential protective effect could yield clues to the underlying etiology of Kawasaki disease. Copyright © 2014. Published by Elsevier Ltd.
    Vaccine 11/2014; 33(2). DOI:10.1016/j.vaccine.2014.10.044 · 3.62 Impact Factor
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    ABSTRACT: To determine the utility of repeated patient-level body mass index (BMI) measurements among higher-risk patients seen at safety-net clinics as a community-level monitoring tool for overweight and obesity population trends. Data from a network of urban, federally qualified community health centers with computerized tracking of BMI at sequential outpatient visits were analyzed. We performed a longitudinal observational study over 8 years (2005-2012) with children stratified by weight status groups on the basis of BMI. Changes in BMI z-scores were used to estimate population trends among children 2 to 11 years old, with at least 2 visits (at least 1 year apart), for whom weight and height were measured. Among children (n = 33,542), the rate of overweight was 16% and rate of obesity was 18% at their last visit. Children were followed for an average of 3.24 ± 1.76 years to measure trends and change in weight status from earlier to later childhood. Children who were obese at first visit had increased odds (adjusted odds ratio 27.8, 95% confidence interval 25.6-30.2) of being obese by last visit. Mean change in BMI z-score per person-year of observation was 0.10 ± 0.38, with a differing rate of change based on weight status category at last visit (not overweight = 0.06 ± 0.39; overweight = 0.17 ± 0.34; obese = 0.19 ± 0.36). Change in BMI z-score per person-year decreased for 40% of obese children; however, their weight status group remained unchanged. Childhood obesity prevalence was high, with substantial progression to overweight and obesity from first to last visit. Clinically derived BMI z-score per person-year measures can effectively show population trends not observed using standard weight status categories. Copyright © 2014 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.
    Academic Pediatrics 11/2014; 14(6):632-8. DOI:10.1016/j.acap.2014.06.007 · 2.01 Impact Factor
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    ABSTRACT: Objective: To describe childhood weight gain using body mass index (BMI) z-score trajectories in a low-income urban safety-net population and identify among gender- and race/ethnicity-specific groups any trends for increased risk. Methods: A retrospective cohort study was conducted among 2- to 12-year-old patients (2006-2013) visiting a safety-net provider. BMI z-score trajectories were calculated overall, for gender- and race/ethnicity-specific groups, and for peak BMI percentile subgroups to describe weight gain longitudinally. Results: From 2006 to 2013, a total of 26,234 eligible children were followed for an average of 3.7 years. At baseline (mean age, 4.2 years), 74% of patients were at a normal weight compared to 65% at most recent observation (mean age, 7.8 years). All gender and race/ethnicity subgroups showed increasing average BMI z-scores during childhood. Children consistently under the 50th percentile and those of white race had the most stable BMI z-score trajectories. BMI z-score increased with increasing age in all subgroups. Hispanic boys and black girls had the most significant increase in BMI z-score during this observation period. Children observed in early childhood and whose BMI exceeded the 95th percentile at any time were often already overweight (20%) or obese (36%) by 3 years of age. Conclusions: The entire population demonstrated an upward trend in BMI z-score trajectory. This trend was most notable among black girls and Hispanic boys. Many obese children were already overweight by age 3, and persistence of obesity after 3 years of age was high, suggesting that intervention before age 3 may be essential to curbing unhealthy weight trajectories.
    Academic Pediatrics 08/2014; 14(6). DOI:10.1016/j.acap.2014.06.009 · 2.01 Impact Factor
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    ABSTRACT: Objective: In response to widespread pertussis outbreaks and infant deaths, in 2010, the California Department of Health (CDPH) and in 2011 the Advisory Committee on Immunization Practices (ACIP) advised that the tetanus toxoid, reduced diphtheria toxoid and acellular pertussis (Tdap) vaccine be administered during pregnancy. The goals of this study were to describe Tdap coverage among pregnant women following these recommendations. Methods: In this observational cohort study, we utilized electronic medical record and claims data from seven Vaccine Safety Datalink sites to identify pregnancies and Tdap administrations. All Tdap doses were classified as pre-pregnancy, during pregnancy or post-pregnancy/postpartum. For pregnancies ending in a live birth, we evaluated factors associated with Tdap vaccination. Results: Among 289,141 live births at the California VSD sites, receipt of Tdap during pregnancy increased substantially in the years 2010, 2011, and 2012, when coverage was 15.9, 30.0 and 19.5%, respectively. Among 82,398 women with live births at the Oregon, Washington, Colorado, Wisconsin and Minnesota VSD sites, receipt of Tdap during pregnancy first increased in 2012, at 16.0%. Women receiving early prenatal care and other vaccine(s) during pregnancy had higher Tdap coverage. Conclusion: We observed substantial increases in Tdap coverage during pregnancy following CDPH and ACIP recommendations.
    Preventive Medicine 06/2014; 67. DOI:10.1016/j.ypmed.2014.05.025 · 3.09 Impact Factor
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    ABSTRACT: Background: Little is known regarding the timing of childhood vaccination and postvaccination seizures. Methods: In a cohort of 323 247 US children from the Vaccine Safety Datalink born from 2004 to 2008, we analyzed the association between the timing of childhood vaccination and the first occurrence of seizure with a self-controlled case series analysis of the first doses of individual vaccines received in the first 2 years of life. Results: In infants, there was no association between the timing of infant vaccination and postvaccination seizures. In the second year of life, the incident rate ratio (IRR) for seizures after receipt of the first measles-mumps-rubella vaccine (MMR) dose at 12 to 15 months was 2.65 (95% confidence interval [CI] 1.99-3.55); the IRR after an MMR dose at 16 to 23 months was 6.53 (95% CI 3.15-13.53). The IRR for seizures after receipt of the first measles-mumps-rubella-varicella vaccine (MMRV) dose at 12 to 15 months was 4.95 (95% CI 3.68-6.66); the IRR after an MMRV dose at 16 to 23 months was 9.80 (95% CI 4.35 -22.06). Conclusions: There is no increased risk of postvaccination seizure in infants regardless of timing of vaccination. In year 2, delaying MMR vaccine past 15 months of age results in a higher risk of seizures. The strength of the association is doubled with MMRV vaccine. These findings suggest that on-time vaccination is as safe with regard to seizures as delayed vaccination in the first year of life, and that delayed vaccination in the second year of life is associated with more postvaccination seizures than on-time vaccination.
    Pediatrics 05/2014; 133(6). DOI:10.1542/peds.2013-3429 · 5.47 Impact Factor
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    ABSTRACT: School-located influenza vaccination (SLIV) may be instrumental in achieving high vaccination rates among children. Sustainability of SLIV programs may require third-party billing. This study assessed, among parents of elementary school students, the attitudes about SLIV and billing at school, as well as factors associated with being supportive of SLIV. We conducted a survey (April 2010 to June 2010) of parents of 1000 randomly selected primarily low-income children at 20 elementary schools at which SLIV with billing had occurred. Response rate was 70% (n = 699). Eighty-one percent agreed (61% strongly) they "would be okay" with SLIV for their child. Many agreed it was better to get vaccinated at their child's doctor's office because they could take care of other health issues (72%) and the doctor knows the child's medical history (65%). However, an equal percentage (47%) thought the best place for influenza vaccination was the child's doctor's office and the child's school. Twenty-five percent did not want to give health insurance information necessary for billing at school. Factors independently associated with strongly supporting SLIV included parental education of high school or less (relative risk 1.30; 95% confidence interval 1.09-1.58), Hispanic ethnicity (1.25; 1.08-1.45); believing the vaccine is efficacious (1.49; 1.23-1.84); and finding school delivery more convenient (2.37; 1.82-3.45). Having concerns about the safety of influenza vaccine (0.80; 0.72-0.88) and not wanting their child to be vaccinated without a parent (0.74; 0.64-0.83) were negatively associated. The majority of parents were supportive of SLIV, although parental concerns about not being present for vaccination and about the safety and efficacy of the vaccine will need to be addressed.
    Academic pediatrics 05/2014; 14(3):241-8. DOI:10.1016/j.acap.2014.01.006 · 2.01 Impact Factor
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    ABSTRACT: To assess rates of immunization; costs of conducting clinics; and reimbursements for a school-located influenza vaccination (SLIV) program that billed third-party payers. SLIV clinics were conducted in 19 elementary schools in the Denver Public School district (September 2010 to February 2011). School personnel obtained parental consent, and a community vaccinator conducted clinics and performed billing. Vaccines For Children vaccine was available for eligible students. Parents were not billed for any fees. Data were collected regarding implementation costs and vaccine cost was calculated using published private sector prices. Reimbursement amounts were compared to costs. Overall, 30% of students (2784 of 9295) received ≥1 influenza vaccine; 39% (1079 of 2784) needed 2 doses and 80% received both. Excluding vaccine costs, implementation costs were $24.69 per vaccination. The percentage of vaccine costs reimbursed was 62% overall (82% from State Child Health Insurance Program (SCHIP), 50% from private insurance). The percentage of implementation costs reimbursed was 19% overall (23% from private, 27% from Medicaid, 29% from SCHIP and 0% among uninsured). Overall, 25% of total costs (implementation plus vaccine) were reimbursed. A SLIV program resulted in vaccination of nearly one third of elementary students. Reimbursement rates were limited by 1) school restrictions on charging parents fees, 2) low payments for vaccine administration from public payers and 3) high rates of denials from private insurers. Some of these problems might be reduced by provisions in the Affordable Care Act.
    Academic pediatrics 05/2014; 14(3):234-40. DOI:10.1016/j.acap.2014.01.005 · 2.01 Impact Factor
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    Kelly B Flett · Kristin Breslin · Patricia A Braun · Simon J Hambidge ·
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    ABSTRACT: Home oxygen has been incorporated into the emergency department management of bronchiolitis in high-altitude settings. However, the outpatient course on oxygen therapy and factors associated with subsequent admission have not been fully defined. We conducted a retrospective cohort study in consecutive patients discharged on home oxygen from the pediatric emergency department at Denver Health Medical Center from 2003 to 2009. The integration of inpatient and outpatient care at our study institution allowed comprehensive assessment of follow-up rates, outpatient visits, time on oxygen, and subsequent admission. Admitted and nonadmitted patients were compared by using a χ(2) test and multivariable logistic regression. We identified 234 unique visits with adequate follow-up for inclusion. The median age was 10 months (interquartile range [IQR]: 7-14 months). Eighty-three percent of patients were followed up within 24 hours and 94% within 48 hours. The median length of oxygen use was 6 days (IQR: 4-9 days), and the median number of associated encounters was 3 (range: 0-9; IQR: 2-3). Ninety-three percent of patients were on room air at 14 days. Twenty-two patients (9.4%) required subsequent admission. Fever at the initial visit (>38.0°C) was associated with admission (P < .02) but had a positive predictive value of 15.4%. Age, prematurity, respiratory rate, oxygen saturation, and history of previous bronchiolitis or wheeze were not associated with admission. There is a significant outpatient burden associated with home oxygen use. Although fever was associated with admission, we were unable to identify predictors that could modify current protocols.
    PEDIATRICS 04/2014; 133(5). DOI:10.1542/peds.2013-1872 · 5.47 Impact Factor
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    ABSTRACT: In 2008, a diphtheria, tetanus, acellular pertussis, and inactivated poliovirus combined vaccine (DTaP-IPV) was licensed for use in children 4 through 6 years of age. While pre-licensure studies did not demonstrate significant safety concerns, the number vaccinated in these studies was not sufficient to examine the risk of uncommon but serious adverse events. To assess the risk of serious adverse events following DTaP-IPV vaccination. The study was conducted from January 2009 through September 2012 in the Vaccine Safety Datalink (VSD) project. In the VSD, electronic vaccination and encounter data are updated and aggregated weekly as part of ongoing surveillance activities. Based on previous reports and biologic plausibility, eight potential adverse events were monitored: meningitis/encephalitis; seizures; stroke; Guillain-Barré syndrome; Stevens-Johnson syndrome; anaphylaxis; serious allergic reactions other than anaphylaxis; and serious local reactions. Adverse event rates in DTaP-IPV recipients were compared to historical incidence rates in the VSD population prior to 2009. Sequential probability ratio testing was used to analyze the data on a weekly basis. During the study period, 201,116 children received DTaP-IPV vaccine. Ninety-seven percent of DTaP-IPV recipients also received other vaccines on the same day, typically measles-mumps-rubella and varicella vaccines. There was no statistically significant increased risk of any of the eight pre-specified adverse events among DTaP-IPV recipients when compared to historical incidence rates. In this safety surveillance study of more than 200,000 DTaP-IPV vaccine recipients, there was no evidence of increased risk for any of the pre-specified adverse events monitored. Continued surveillance of DTaP-IPV vaccine safety may be warranted to monitor for rare adverse events, such as Guillain-Barré syndrome.
    Vaccine 03/2014; 32(25). DOI:10.1016/j.vaccine.2014.03.063 · 3.62 Impact Factor

Publication Stats

1k Citations
442.15 Total Impact Points


  • 2008-2015
    • Kaiser Permanente
      • Center for Health Research (Oregon, Hawaii, and Georgia)
      Oakland, California, United States
  • 2006-2014
    • University of Colorado
      • • Department of Pediatrics
      • • Department of Family Medicine
      Denver, Colorado, United States
  • 2009
    • Community College of Denver
      Denver, Colorado, United States
  • 2002-2006
    • University of Colorado Hospital
      • Department of Pediatrics
      Denver, Colorado, United States
  • 2002-2004
    • Denver Health and Hospital Authority
      Denver, Colorado, United States