Prevalence of Adolescents Meeting Criteria for Metabolic and Bariatric Surgery.

BACKGROUND AND OBJECTIVES: The American Academy of Pediatrics endorses metabolic and bariatric surgery (MBS) as a safe and effective treatment of severe obesity in children with class 3 obesity or with class 2 obesity and qualifying comorbidities. The study objective was to determine eligibility and characteristics of adolescents who qualify for MBS based on American Academy of Pediatrics guidelines. METHODS: This retrospective cohort study analyzed electronic health record data of 603 051 adolescents aged 13 to 17 years between January 1, 2018, and December 31, 2021. Centers for Disease Control and Prevention criteria were used to define obesity classes 2 and 3. Multivariable logistic regression was used to evaluate the factors associated with meeting MBS eligibility criteria. RESULTS: Of the 603 041 adolescents evaluated, 22.2% had obesity (12.9% class 1, 5.4% class 2, and 3.9% class 3). The most frequently diagnosed comorbid conditions were gastroesophageal reflux disease (3.2%), hypertension (0.5%), and nonalcoholic fatty liver disease (0.5%). Among adolescents with class 2 obesity, 9.1% had 1 or more comorbidities qualifying for MBS, and 4.4% of all adolescents met the eligibility criteria for MBS. In multivariable modeling, males, Black and Hispanic adolescents, and those living in more deprived neighborhoods were more likely to meet MBS eligibility criteria. CONCLUSIONS: Overall, 1 in 23 adolescents met the eligibility criteria for MBS. Demographic and social determinants were associated with a higher risk for meeting these criteria. The study suggests that the health care system may face challenges in accommodating the demand for MBS among eligible adolescents.

Characteristics of adults with overweight and obesity who have not attempted weight loss in the prior 12 months.

OBJECTIVE: To determine weight-related characteristics of adults with overweight or obesity who had not attempted weight loss in the prior 12 months. METHODS: Adults from the obesity cohort of the PORTAL clinical data research network were randomly selected to complete a survey in 2015. It included topics of experiences with health care providers, weight history, and health-promoting behaviors. RESULTS: A total of 2811 adults completed the survey, of whom 24% reported not attempting weight loss in the previous 12 months. Controlling for sociodemographic characteristics and body mass index, respondents who reported that their health care provider never talked about weight were more likely to not attempt weight loss in the previous 12 months compared with respondents who reported providers frequently brought up weight (OR: 0.45; 95% CI: 0.24, 0.66). Respondents who perceived themselves as normal weight or underweight were 4.22 times more likely (95% CI: 3.53, 5.05) to not attempt weight loss compared with respondents who perceived themselves as overweight. Respondents who reported that they never tried to lose at least 10 lbs, ate 0-2 servings of fruits and vegetables daily, or engaged in 0-29 min of physical activity weekly were less likely to attempt weight loss. CONCLUSIONS: Receiving advice on weight loss from health care providers to improve awareness of overweight and obesity status may be important factors for a person's weight management. Provider discussions about weight may be a strategy to motivate weight loss attempts.

Bariatric Surgery is Associated With Reduced Risk of Breast Cancer in Both Premenopausal and Postmenopausal Women.

OBJECTIVE: This retrospective cohort study examined whether bariatric surgery is associated with reduced risk of breast cancer among pre- and postmenopausal women. BACKGROUND: Obesity is associated with increased risk of breast cancer, but the impact of weight loss on breast cancer risk has been difficult to quantify. METHODS: The cohort included obese (body mass index ≥35 kg/m) patients enrolled in an integrated health care delivery system between 2005 and 2012 (with follow-up through 2014). Female bariatric surgery patients (N = 17,998) were matched on body mass index, age, study site, and comorbidity index to 53,889 women with no bariatric surgery. Kaplan-Meier curves and Cox proportional hazards models were used to examine incident breast cancer up to 10 years after bariatric surgery. Pre- and postmenopausal women were examined separately, and further classified by estrogen receptor (ER) status. RESULTS: The analysis included 301 premenopausal and 399 postmenopausal breast cancer cases. In multivariable adjusted models, bariatric surgery was associated with a reduced risk of both premenopausal (HR = 0.72, 95% CI, 0.54-0.94) and postmenopausal (HR = 0.55, 95% CI, 0.42-0.72) breast cancer. Among premenopausal women, the effect of bariatric surgery was more pronounced among ER-negative cases (HR = 0.36, 95% CI, 0.16-0.79). Among postmenopausal women, the effect was more pronounced in ER-positive cases (HR = 0.52, 95% CI, 0.39-0.70). CONCLUSIONS: Bariatric surgery was associated with a reduced risk of breast cancer among severely obese women. These findings have significant public health relevance because the prevalence of obesity continues to rise, and few modifiable breast cancer risk factors have been identified, especially for premenopausal women.

Bariatric Surgery and the Risk of Cancer in a Large Multisite Cohort.

OBJECTIVE: To determine whether bariatric surgery is associated with a lower risk of cancer. BACKGROUND: Obesity is strongly associated with many types of cancer. Few studies have examined the relationship between bariatric surgery and cancer risk. METHODS: We conducted a retrospective cohort study of patients undergoing bariatric surgery between 2005 and 2012 with follow-up through 2014 using data from a large integrated health insurance and care delivery systems with 5 study sites. The study included 22,198 subjects who had bariatric surgery and 66,427 nonsurgical subjects matched on sex, age, study site, body mass index, and Elixhauser comorbidity index. Multivariable Cox proportional-hazards models were used to examine incident cancer up to 10 years after bariatric surgery compared to the matched nonsurgical patients. RESULTS: After a mean follow-up of 3.5 years, we identified 2543 incident cancers. Patients undergoing bariatric surgery had a 33% lower hazard of developing any cancer during follow-up [hazard ratio (HR) 0.67, 95% confidence interval (CI) 0.60, 0.74, P < 0.001) compared with matched patients with severe obesity who did not undergo bariatric surgery, and results were even stronger when the outcome was restricted to obesity-associated cancers (HR 0.59, 95% CI 0.51, 0.69, P < 0.001). Among the obesity-associated cancers, the risk of postmenopausal breast cancer (HR 0.58, 95% CI 0.44, 0.77, P < 0.001), colon cancer (HR 0.59, 95% CI 0.36, 0.97, P = 0.04), endometrial cancer (HR 0.50, 95% CI 0.37, 0.67, P < 0.001), and pancreatic cancer (HR 0.46, 95% CI 0.22, 0.97, P = 0.04) was each statistically significantly lower among those who had undergone bariatric surgery compared with matched nonsurgical patients. CONCLUSIONS: In this large, multisite cohort of patients with severe obesity, bariatric surgery was associated with a lower risk of incident cancer, particularly obesity-associated cancers, such as postmenopausal breast cancer, endometrial cancer, and colon cancer. More research is needed to clarify the specific mechanisms through which bariatric surgery lowers cancer risk.

Longitudinal Increases in Adiposity Contribute to Worsening Adipokine Profile over Time in Mexican Americans.

OBJECTIVE: Limited studies have assessed the relationship between longitudinal changes in adiposity and changes in multiple adipokines over time. This study examined changes in BMI, total body fat, and trunk fat associated with changes in 16 circulating adipokines in Mexican Americans at risk for type 2 diabetes. METHODS: Participants included 1,213 individuals with cross-sectional data and a subset of 368 individuals with follow-up measures (mean 4.6 ± 1.5 years from baseline). Joint multivariate associations between 3 adiposity measures and 16 adipokines were assessed by canonical correlation analysis. RESULTS: Longitudinal increases in adiposity were most strongly associated with increasing leptin, C-reactive protein (CRP), and interleukin 1 receptor antagonist (IL-1Ra) and decreasing adiponectin and secreted frizzled protein 5 (SFRP5) over time. Participants with BMI ≥ 30 kg/m2 at baseline had greater increases in leptin, CRP, IL-1Ra, and interleukin 6 (IL-6) and greater decreases in adiponectin and SFRP5, associated with increasing adiposity over follow-up, than those with BMI < 30 kg/m2 . Associations between adiposity and adipokines were most accounted for by leptin; adjustment for leptin greatly reduced the magnitude of all associations between adiposity and remaining adipokines. CONCLUSIONS: Increasing adiposity contributes to a worsening imbalance of pro- and anti-inflammatory adipokines over time, in which leptin may have an important role as a key mediator of metabolic disease risk in Mexican Americans.

Association Between Weight Loss and the Risk of Cancer after Bariatric Surgery.

OBJECTIVE: The goal of this study was to determine whether the reduction in cancer risk after bariatric surgery is due to weight loss. METHODS: A retrospective matched cohort study of patients undergoing bariatric surgery was conducted using data from a large integrated health insurance and care delivery system with five sites in four states. The study included 18,355 bariatric surgery subjects and 40,524 nonsurgical subjects matched on age, sex, BMI, site, and Elixhauser comorbidity index. Multivariable Cox proportional hazards models examined the relationship between weight loss at 1 year and incident cancer during up to 10 years of follow-up. RESULTS: The study identified 1,196 cases of incident cancer. The average 1-year postsurgical weight loss was 27% among patients undergoing bariatric surgery versus 1% in matched nonsurgical patients. Percent weight loss at 1 year was significantly associated with a reduced risk of any cancer in adjusted models (HR 0.897, 95% CI: 0.832-0.968, P = 0.005 for every 10% weight loss) while bariatric surgery was not a significant independent predictor of cancer incidence. CONCLUSIONS: Weight loss after bariatric surgery was associated with a lower risk of incident cancer. There was no apparent independent effect of the bariatric surgery itself on cancer risk that was independent of weight loss.

Understanding the Capacity for Exercise in Post-Bariatric Patients.

PURPOSE: The aim of this study is to conduct a pilot randomized trial testing an exercise program specifically adapted for post-bariatric patients. METHODS: A total of 51 post-bariatric patients, 6-24 months post-surgery, were randomly assigned to usual care control (n = 25) or the exercise intervention (n = 26). The intervention included twice weekly 60-min group exercise classes with functional strength, flexibility, and aerobic activities; at least 3 days per week of self-directed exercise; daily pedometer; recording of steps and activities; and weekly telephone counseling. There was also a 6-month maintenance period. RESULTS: Patients were 49 ± 12 years old, 84 % female, 59 % non-Hispanic white, with a BMI of 32.9 ± 5.7 kg/m2 and percent excess BMI loss since surgery of 56 ± 35 %. Patients were 14 ± 5 months post-surgery. A total of 44 patients (86 %) completed both phases of the program and all assessments. The following measures improved significantly for intervention participants with no significant change in control participants: yards walked in 6 min, seconds for 8-foot up-and-go, number of arm curls, and distance in inches for chair sit-and-reach. Intervention changes remained after 6 months of maintenance. CONCLUSIONS: When compared to patients in usual care, a specially adapted exercise program for post-bariatric patients resulted in significant improvements in objectively monitored health outcomes. This program was delivered in a clinical setting and could be implemented in a variety of settings to improve health outcomes for post-bariatric patients.

Screening for High Blood Pressure in Adults During Ambulatory Nonprimary Care Visits: Opportunities to Improve Hypertension Recognition.

Visits with nonprimary care providers such as optometrists may be missed opportunities for the detection of high blood pressure (BP). For this study, normotensive adults with at least 12 months of health plan membership on January 1, 2009 (n=1,075,522) were followed-up for high BP through March 14, 2011. Of 111,996 patients with a BP measurement ≥140/90 mm Hg, 82.7% were measured during primary care visits and 17.3% during nonprimary care visits. Individuals with a BP ≥140/90 mm Hg measured during nonprimary care visits were older and more likely to be male and non-Hispanic white. The proportion of patients with follow-up and false-positives were comparable between primary and nonprimary care. The main nonprimary care specialty to identify a first BP ≥140/90 mm Hg was ophthalmology/optometry with 24.5% of all patients. Results suggest that expanding screening for hypertension to nonprimary care settings may improve the detection of hypertension.

Metabolic syndrome is less likely to resolve in Hispanics and non-Hispanic blacks after bariatric surgery.

OBJECTIVE: To determine predictors of metabolic syndrome and its resolution in a large, ethnically diverse adult population undergoing bariatric surgery. BACKGROUND: There is still limited knowledge about the impact of bariatric surgery on chronic health conditions such as metabolic syndrome. METHODS: Adults having had a laparoscopic Roux-en-Y gastric bypass or a laparoscopic vertical sleeve gastrectomy between 2007 and 2009 (n = 4088) without revision during the study period of January 1, 2007 through December 31, 2011 were eligible for the study. Diagnosis and resolution of metabolic syndrome were determined using standard criteria with electronic medical records of laboratory, diagnosis, and pharmacy information. RESULTS: Patients were primarily women (82%), non-Hispanic black (17%) or Hispanic (32%), 45 ± 11 years old, and had a body mass index (BMI) of 47.10 ± 7.73 kg/m at the time of surgery. After multivariate adjustment, metabolic syndrome was less likely to resolve in patients if they had a laparoscopic vertical sleeve gastrectomy procedure and a higher BMI at surgery, were older, were male or were either Hispanic or non-Hispanic black. The effects of age, race/ethnicity, and BMI at the time of surgery remained after accounting for weight loss. CONCLUSIONS: On the basis of our findings, bariatric surgery may be most effective for younger, less obese patients who are early in the course of their cardiometabolic disease. Future research should investigate the factors that lead to lower rates of disease resolution after bariatric surgery for racial/ethnic minority groups.

High blood pressure in overweight and obese youth: implications for screening.

In the absence of evidence-based guidelines for high blood pressure screening in asymptomatic youth, a reasonable strategy is to screen those who are at high risk. The present study aimed to identify optimal body mass index (BMI) thresholds as a marker for high-risk youth to predict hypertension prevalence. In a cross-sectional study, youth aged 6 to 17 years (n=237,248) enrolled in an integrated prepaid health plan in 2007 to 2009 were classified according to their BMI and hypertension status. In moderately and extremely obese youth, the prevalence of hypertension was 3.8% and 9.2%, respectively, compared with 0.9% in normal weight youth. The adjusted prevalence ratios (95% confidence intervals) of hypertension for normal weight, overweight, moderate obesity, and extreme obesity were 1.00 (Reference), 2.27 (2.08-2.47), 4.43 (4.10-4.79), and 10.76 (9.99-11.59), respectively. The prevalence of hypertension was best predicted by a BMI-for-age ≥94th percentile. These results suggest that all obese youth should be screened for hypertension.

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. PATIENT(S): Adolescents aged 15-19 years (n = 137,502). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): PCOS diagnosed or defined according to National Institutes of Health (NIH) criteria. RESULT(S): The prevalence of a confirmed diagnosis of PCOS was 0.56%, which increased to 1.14% when undiagnosed cases with documented symptoms qualifying for PCOS according to NIH criteria were included. Compared with normal/underweight girls, the odds ratios (OR and 95% confidence interval [CI]) for confirmed PCOS diagnosis were 3.85 (3.04-4.88), 10.25 (8.16-12.84), and 23.10 (18.66-28.61) for overweight, moderately obese, and extremely obese adolescents, respectively, after adjusting for potential confounders. When adolescents with two or more supportive diagnoses were included (diagnosed and undiagnosed PCOS-NIH), the ORs (95% CI) for PCOS-NIH by weight class were significantly attenuated to 2.95 (2.53-3.44), 6.73 (5.78-7.83), and 14.65 (12.73-16.86) for overweight, moderately obese, and extremely obese adolescents, respectively. CONCLUSION(S): Overweight and obesity were associated with higher odds of PCOS in adolescents. Studies based solely on diagnosis codes may underestimate the prevalence of PCOS and overestimate the magnitude of the association between obesity and PCOS.

The accuracy and trends of smoking history documentation in electronic medical records in a large managed care organization.

The accuracy of smoking history documentation in the electronic medical records was examined at a large managed care organization among 36,494 male members who self-reported smoking history in mailed surveys. The sensitivity of electronic smoking history documentation for ever-smoking status was 0.19 in years 2003-2005 (using ICD-9/CPT code only), 0.80 in 2006-2008 and 0.84 in 2009-2010 (combination of ICD-9/CPT codes and risk factor module used after 2006). The positive predictive value was 0.96, 0.90, and 0.95 in these periods, respectively. Among self-reported ever-smokers, increased healthcare utilization and smoking intensity/duration were associated with higher likelihood of having electronic smoking history documentation, while Asian race and Spanish language preference were associated with lower likelihood. These data suggest that enhanced efforts may be needed to screen for and document smoking among racial/ethnic minorities.

OBAYA (obesity and adverse health outcomes in young adults): feasibility of a population-based multiethnic cohort study using electronic medical records.

BACKGROUND: Although obesity is a risk factor for many chronic diseases, we have only limited knowledge of the magnitude of these associations in young adults. A multiethnic cohort of young adults was established to close current knowledge gaps; cohort demographics, cohort retention, and the potential influence of migration bias were investigated. METHODS: For this population-based cross-sectional study, demographics, and measured weight and height were extracted from electronic medical records of 1,929,470 patients aged 20 to 39 years enrolled in two integrated health plans in California from 2007 to 2009. RESULTS: The cohort included about 84.4% of Kaiser Permanente California members in this age group who had a medical encounter during the study period and represented about 18.2% of the underlying population in the same age group in California. The age distribution of the cohort was relatively comparable to the underlying population in California Census 2010 population, but the proportion of women and ethnic/racial minorities was slightly higher. The three-year retention rate was 68.4%. CONCLUSION: These data suggest the feasibility of our study for medium-term follow-up based on sufficient membership retention rates. While nationwide 6% of young adults are extremely obese, we know little to adequately quantify the health burden attributable to obesity, especially extreme obesity, in this age group. This cohort of young adults provides a unique opportunity to investigate associations of obesity-related factors and risk of cancer in a large multiethnic population.

The prevalence of obesity and obesity-related health conditions in a large, multiethnic cohort of young adults in California.

PURPOSE: To identify population groups that are most susceptible to obesity-related health conditions at young age. METHODS: For this population-based cross-sectional study, measured weight and height, diagnosis, laboratory, and drug prescription information were extracted from electronic medical records of 1,819,205 patients aged 20 to 39 years enrolled in two integrated health plans in California in 2007 through 2009. RESULTS: Overall, 29.9% of young adults were obese. Extreme obesity (body mass index [BMI] ≥ 40 kg/m(2)) was observed in 6.1% of women and 4.5% of men. The adjusted relative risk (RR) for diabetes, hypertension, dyslipidemia, and the metabolic syndrome increased sharply for those individuals with a BMI of 40 or greater, with the sharpest increase in the adjusted RR for hypertension and the metabolic syndrome. The association between weight class and dyslipidemia, hypertension, and the metabolic syndrome but not diabetes was stronger among 20.0- to 29.9-year-olds compared with 30.0- to 39.9-year-olds (P for interaction < .05). For example, compared with their normal weight counterparts of the same age group, young adults with a BMI of 40.0 to 49.9, 50.0 to 59.9, and 60 or greater kg/m(2) had a RR for hypertension of 11.73, 19.88, and 30.47 (95% confidence interval [CI], 26.39-35.17) at 20 to 29 years old, and 9.31, 12.41, and 15.43 (95% CI, 14.32-16.63) at 30 to 39 years old. CONCLUSIONS: Although older individuals were more likely to be extremely obese, the association between obesity-related health conditions was stronger in younger individuals. Hispanics and Blacks are also more likely to be obese, including extremely obese, putting them at an elevated risk for premature cardiovascular disease and some cancers relative to non-Hispanic Whites.

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. A combination of electronic database searches followed by complete medical records review was used to identify all children diagnosed with IIH between 2006 and 2009. RESULTS: We identified 78 children with IIH, the majority of whom were girls (n = 66, 84.5%), age 11-19 (n = 66, 84.5%), non-Hispanic Whites (n = 37, 47.4%), and overweight or obese (n = 57, 73.1%). The adjusted ORs and 95% CIs of IIH with increasing weight class were 1.00, 3.56 (1.72-7.39), 6.45 (3.10-13.44), and 16.14 (8.18-31.85) for underweight/normal weight (reference category), overweight, moderately obese and extremely obese 11-19 year olds, respectively (P for trend < .001). Other independent IIH risk factors included White non-Hispanic race/ethnicity for all age groups and female sex, but only in older children. Overweight/obese children also had more IIH symptoms at onset than normal weight children. CONCLUSIONS: We found that childhood obesity is strongly associated with an increased risk of pediatric IIH in adolescents. Our findings suggest that the childhood obesity epidemic is likely to lead to increased morbidity from IIH particularly among extremely obese, White non-Hispanic teenage girls. Our findings also suggest careful screening of these at risk individuals may lead to earlier detection and opportunity for treatment of IIH.

Bilateral oophorectomy is not associated with increased mortality: the California Teachers Study.

OBJECTIVE: To investigate the effect of surgical menopause due to bilateral oophorectomy on mortality, in light of evidence that bilateral oophorectomy among premenopausal women rapidly reduces endogenous hormone levels, thereby modifying risks of cardiovascular disease and breast cancer. DESIGN: The California Teachers Study (CTS) is a prospective cohort study of 133,479 women initiated in 1995-1996 through a mailed, self-administered questionnaire. Relative risks and 95% confidence intervals (CI) were estimated using Cox proportional hazards regression. SETTING: None. PATIENT(S): California Teachers Study participants who, at baseline, reported having surgical menopause due to bilateral oophorectomy (n = 9,785), were compared with participants with natural menopause (n = 32,219). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): We investigated whether bilateral oophorectomy was associated with all-cause, cardiovascular, or cancer mortality, overall and by menopausal hormone therapy use status. RESULT(S): Among participants aged <45 years at menopause, multivariable relative risks were 0.86 (95% CI, 0.74-1.00), 0.85 (95% CI, 0.66-1.11), and 0.91 (95% CI, 0.67-1.23) for all-cause mortality, cardiovascular mortality, and cancer mortality, respectively. Among participants with an age at menopause of ≥45 years, multivariable relative risks were 0.87 (95% CI, 0.80-0.94), 0.83 (95% CI, 0.71-0.96), and 0.84 (95% CI, 0.72-0.98) for all-cause, cardiovascular, and cancer mortality, respectively. The association between bilateral oophorectomy and mortality did not differ by baseline status of hormone therapy use. CONCLUSION(S): Surgical menopause due to bilateral oophorectomy vs. natural menopause does not increase all-cause, cardiovascular, or cancer mortality.

Trends in meat consumption in the USA.

OBJECTIVE: To characterize the trends, distribution, potential determinants and public health implications of meat consumption within the USA. DESIGN: We examined temporal trends in meat consumption using food availability data from the FAO and US Department of Agriculture (USDA), and further evaluated the meat intake by type (red, white, processed) in the National Health and Nutrition Examination Surveys (NHANES) linked to the MyPyramid Equivalents Database (MPED). RESULTS: Overall meat consumption has continued to rise in the USA and the rest of the developed world. Despite a shift towards higher poultry consumption, red meat still represents the largest proportion of meat consumed in the USA (58 %). Twenty-two per cent of the meat consumed in the USA is processed. According to the NHANES 2003-2004, total meat intake averaged 128 g/d. The type and quantities of meat reported varied by education, race, age and gender. CONCLUSIONS: Given the plausible epidemiological evidence for red and processed meat intake in cancer and chronic disease risk, understanding the trends and determinants of meat consumption in the USA, where meat is consumed at more than three times the global average, should be particularly pertinent to researchers and other public health professionals aiming to reduce the global burden of chronic disease.

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. METHODS: For this population-based, cross-sectional study, measured weight and height and diagnosis of GERD were extracted from electronic medical records of 690 321 patients, aged 2-19 years, who were enrolled in an integrated prepaid health plan between 2007 and 2008. Weight class (normal weight, overweight, moderate and extreme obesity) was assigned based on body mass index-for-age. RESULTS: Overall, GERD was diagnosed in 1.5% of boys and 1.8% of girls (P<0.001). Moderately and extremely obese children, aged 6-11 years, were more likely to have a diagnosis of GERD compared with normal weight (OR 1.16, 95% CI: 1.02-1.32 and 1.32, 95% CI: 1.13-1.56, respectively). Children aged 12-19 years showed similar associations (OR 1.16, 95% CI: 1.07-1.25 and 1.40, 95% CI: 1.28-1.52, respectively). These associations remained with adjustment for sex and race/ethnicity. By contrast, obesity was not related to increased odds for GERD in children aged 2-5 years of age. CONCLUSIONS: The association between childhood obesity and GERD may have important implications for their future risk of GERD-associated diseases, such as esophageal adenocarcinoma.

Prospective study of body mass index, physical activity and thyroid cancer.

Increased body size and physical inactivity are positively related to risk of several cancers, but only few epidemiologic studies have investigated body-mass index (BMI) and physical activity in relation to thyroid cancer. We examined the relations of BMI and physical activity to thyroid cancer in a prospective cohort of 484,326 United States men and women, followed from 1995/1996 to 2003. During 3,490,300 person-years of follow-up, we documented 352 newly incident cases of thyroid cancer. The multivariate relative risks (RR) of thyroid cancer for BMI values of 18.5-24.9 (reference), 25.0-29.9 and >/=30 kg m(-2) were 1.0, 1.27 and 1.39 [95% confidence interval (CI) = 1.05-1.85]. Adiposity predicted papillary thyroid cancers (RR comparing extreme BMI categories = 1.47; 95% CI = 1.03-2.10) and, based on small numbers, suggestively predicted follicular thyroid cancers (RR = 1.49; 95% CI = 0.79-2.82) and anaplastic thyroid cancers (RR = 5.80; 95% CI = 0.99-34.19). No relation with BMI was noted for medullary thyroid cancers (RR = 0.97; 95% CI = 0.27-3.43). The positive relation of BMI to total thyroid cancer was evident for men but not for women. However, the test of interaction (p = 0.463) indicated no statistically significant gender difference. Physical activity was unassociated with thyroid cancer. The RRs of total thyroid cancer for low (reference), intermediate, and high level of physical activity were 1.0, 1.01 and 1.01 (95% CI = 0.76-1.34, p for trend = 0.931), respectively. Our results support an adverse effect of adiposity on risk for developing total and papillary, and possibly follicular thyroid cancers. Based on only 15 cases, adiposity was unrelated to medullary thyroid cancers. Physical activity was unrelated to total thyroid cancer.