Hematopoietic stem and progenitor cell-restricted Cdx2 expression induces transformation to myelodysplasia and acute leukemia.

The caudal-related homeobox transcription factor CDX2 is expressed in leukemic cells but not during normal blood formation. Retroviral overexpression of Cdx2 induces AML in mice, however the developmental stage at which CDX2 exerts its effect is unknown. We developed a conditionally inducible Cdx2 mouse model to determine the effects of in vivo, inducible Cdx2 expression in hematopoietic stem and progenitor cells (HSPCs).

Failure to confirm high blood pressures in pediatric care-quantifying the risks of misclassification.

Pediatric practice guidelines call for repeating an elevated office blood pressure (BP) at the same visit, but there are few data available to support this recommendation. We compared the visit results in children aged 3 to 17 years with a BP reading ≥95th percentile (n = 186 732) based on the initial BP and the mean of two BP readings, using electronic medical records from 2012-2015. Failure to repeat an initial BP reading ≥95th percentile would lead to a false "hypertensive" visit result in 54.

Prevalence of polycystic ovary syndrome in adolescents.

Objective: To investigate the prevalence of polycystic ovary syndrome (PCOS) in adolescents and its association with obesity.

Design: Cross-sectional study using electronic medical records.

Setting: Not applicable.

Associations between childhood obesity and upper and lower extremity injuries.

Objectives: To estimate the overall and age-specific associations between obesity and extremity musculoskeletal injuries and pain in children.

Methods: This cross-sectional study used information from electronic medical records of 913178 patients aged 2-19 years enrolled in an integrated health plan in the period 2007-2009. Children were classified as underweight, normal weight, overweight, or moderately/extremely obese and, using multivariable logistic regression methods, the associations between weight class and diagnosis of upper or lower extremity fractures, sprains, dislocations and pain were calculated.

Pediatric idiopathic intracranial hypertension and extreme childhood obesity.

Objective: To estimate the magnitude of the association between overweight, moderate, and extreme childhood obesity and the risk of idiopathic intracranial hypertension (IIH).

Study Design: Risk estimates were obtained from the Kaiser Permanente Southern California Children's Health Study (n = 913 178). Weight classes were assigned by body mass index specific for age and sex.

Pediatric obesity and gallstone disease.

Objectives: The aim of the present study was to investigate the association between childhood and adolescent obesity, the risk of gallstones, and the potential effect modification by oral contraceptive use in girls.

Methods: For this population-based cross-sectional study, measured weight and height, oral contraceptive use, and diagnosis of cholelithiasis or choledocholithiasis were extracted from the electronic medical records of 510,816 patients ages 10 to 19 years enrolled in an integrated health plan, 2007-2009.

Results: We identified 766 patients with gallstones.

Higher prevalence of obesity among children with asthma.

The aim of this study is to investigate the association between childhood obesity and asthma, and whether this relationship varies by race/ethnicity. For this population-based, cross-sectional study, measured weight and height, and asthma diagnoses were extracted from electronic medical records of 681,122 patients aged 6-19 years who were enrolled in an integrated health plan 2007-2009. Weight class was assigned based on BMI-for-age.

Implementation of clinical practice guidelines for pediatric weight management.

Objective: To evaluate the effect of computer-assisted decision tools that standardize pediatric weight management in a large, integrated health care system for the diagnosis and management of child and adolescent obesity.

Study Design: This was a large scale implementation study to document the impact of the Kaiser Permanente Southern California Pediatric Weight Management Initiative. An average of 739, 816 outpatient visits per year in children and adolescents from 2007 to 2010 were analyzed.

The association of psoriasis and elevated blood lipids in overweight and obese children.

Objective: To investigate whether obesity and cardiovascular risk factors are associated with psoriasis in children and adolescents.

Study Design: For this population-based, cross-sectional study, measured weight and height, laboratory data, and psoriasis diagnoses were extracted from electronic medical records of 710,949 patients age 2 to 19 years enrolled in an integrated health plan. Weight class was assigned on the basis of body mass index-for-age.

Low prevalence of psoriasis among children and adolescents in a large multiethnic cohort in southern California.

Background: Little information is available on the prevalence of psoriasis in children and adolescents.

Objective: We sought to estimate the prevalence of pediatric psoriasis in southern California and to investigate the validity of psoriasis diagnosis by a dermatologist compared with a nondermatologist.

Methods: In a southern California population of 710,949 children who were enrolled in an integrated prepaid health plan in 2007 through 2008, cases of psoriasis were identified from electronic medical records and validated by medical chart review.

Extreme childhood obesity is associated with increased risk for gastroesophageal reflux disease in a large population-based study.

Objective: Gastroesophageal reflux disease (GERD) may link the obesity epidemic to an array of adverse health outcomes including chronic esophageal inflammation and, consequentially, to pathophysiological changes of the esophagus. Although obesity and GERD are associated in adults, data in children are scarce and inconclusive. The aim of this study is to investigate whether, similar to adults, obesity is associated with GERD in youth.

Prevalence of extreme obesity in a multiethnic cohort of children and adolescents.

Objective: To estimate the prevalence of extreme obesity in a large, multiethnic contemporary cohort of children and adolescents.

Study Design: In a cross-sectional study, measured weight and height were extracted from electronic medical records of 710,949 patients aged 2 to 19 years (87.8% of eligible patients) who were enrolled in an integrated prepaid health plan in 2007 and 2008.

Body weight and height data in electronic medical records of children.

Objective: Data entry errors may occur in body weights and heights assessed during routine medical care. These errors may affect data quality markedly and create a large number of biologically implausible values. To address this issue, we evaluated the quality of body weight and height measures for children based on sequential health care encounters.

Trends in nonalcoholic fatty liver disease-related hospitalizations in US children, adolescents, and young adults.

Objective: To investigate temporal trends of nonalcoholic fatty liver disease (NAFLD) and obesity among hospitalized US children, adolescents, and young adults over the past 2 decades and to examine potential sex disparities in NAFLD hospitalizations.

Methods: Hospitalization discharges with NAFLD or obesity were identified among children and young adults (6-25 years, weighted n = 91,687,413) from the 1986 to 2006 National Hospital Discharge Survey data. Age- and sex-specific rates and trends in hospitalizations with NAFLD and obesity were estimated.