Brian K. Kit

Prevalence of Childhood and Adult Obesity in the United States, 2011-2012

IMPORTANCE More than one-third of adults and 17% of youth in the United States are obese, although the prevalence remained stable between 2003-2004 and 2009-2010. OBJECTIVE To provide the most recent national estimates of childhood obesity, analyze trends in childhood obesity between 2003 and 2012, and provide detailed obesity trend analyses among adults. DESIGN, SETTING, AND PARTICIPANTS Weight and height or recumbent length were measured in 9120 participants in the 2011-2012 nationally representative National Health and Nutrition Examination Survey. MAIN OUTCOMES AND MEASURES In infants and toddlers from birth to 2 years, high weight for recumbent length was defined as weight for length at or above the 95th percentile of the sex-specific Centers for Disease Control and Prevention (CDC) growth charts. In children and adolescents aged 2 to 19 years, obesity was defined as a body mass index (BMI) at or above the 95th percentile of the sex-specific CDC BMI-for-age growth charts. In adults, obesity was defined as a BMI greater than or equal to 30. Analyses of trends in high weight for recumbent length or obesity prevalence were conducted overall and separately by age across 5 periods (2003-2004, 2005-2006, 2007-2008, 2009-2010, and 2011-2012). RESULTS In 2011-2012, 8.1% (95% CI, 5.8%-11.1%) of infants and toddlers had high weight for recumbent length, and 16.9% (95% CI, 14.9%-19.2%) of 2- to 19-year-olds and 34.9% (95% CI, 32.0%-37.9%) of adults (age-adjusted) aged 20 years or older were obese. Overall, there was no significant change from 2003-2004 through 2011-2012 in high weight for recumbent length among infants and toddlers, obesity in 2- to 19-year-olds, or obesity in adults. Tests for an interaction between survey period and age found an interaction in children (P = .03) and women (P = .02). There was a significant decrease in obesity among 2- to 5-year-old children (from 13.9% to 8.4%; P = .03) and a significant increase in obesity among women aged 60 years and older (from 31.5% to 38.1%; P = .006). CONCLUSIONS AND RELEVANCE Overall, there have been no significant changes in obesity prevalence in youth or adults between 2003-2004 and 2011-2012. Obesity prevalence remains high and thus it is important to continue surveillance.

Prevalence of Obesity and Trends in the Distribution of Body Mass Index Among US Adults, 1999-2010

CONTEXT Between 1980 and 1999, the prevalence of adult obesity (body mass index [BMI] ≥30) increased in the United States and the distribution of BMI changed. More recent data suggested a slowing or leveling off of these trends. OBJECTIVE To estimate the prevalence of adult obesity from the 2009-2010 National Health and Nutrition Examination Survey (NHANES) and compare adult obesity and the distribution of BMI with data from 1999-2008. DESIGN, SETTING, AND PARTICIPANTS NHANES includes measured heights and weights for 5926 adult men and women from a nationally representative sample of the civilian noninstitutionalized US population in 2009-2010 and for 22,847 men and women in 1999-2008. MAIN OUTCOME MEASURES The prevalence of obesity and mean BMI. RESULTS In 2009-2010 the age-adjusted mean BMI was 28.7 (95% CI, 28.3-29.1) for men and also 28.7 (95% CI, 28.4-29.0) for women. Median BMI was 27.8 (interquartile range [IQR], 24.7-31.7) for men and 27.3 (IQR, 23.3-32.7) for women. The age-adjusted prevalence of obesity was 35.5% (95% CI, 31.9%-39.2%) among adult men and 35.8% (95% CI, 34.0%-37.7%) among adult women. Over the 12-year period from 1999 through 2010, obesity showed no significant increase among women overall (age- and race-adjusted annual change in odds ratio [AOR], 1.01; 95% CI, 1.00-1.03; P = .07), but increases were statistically significant for non-Hispanic black women (P = .04) and Mexican American women (P = .046). For men, there was a significant linear trend (AOR, 1.04; 95% CI, 1.02-1.06; P < .001) over the 12-year period. For both men and women, the most recent 2 years (2009-2010) did not differ significantly (P = .08 for men and P = .24 for women) from the previous 6 years (2003-2008). Trends in BMI were similar to obesity trends. CONCLUSION In 2009-2010, the prevalence of obesity was 35.5% among adult men and 35.8% among adult women, with no significant change compared with 2003-2008.

Trends in Obesity Prevalence Among Children and Adolescents in the United States, 1988-1994 Through 2013-2014

IMPORTANCE Previous analyses of obesity trends among children and adolescents showed an increase between 1988-1994 and 1999-2000, but no change between 2003-2004 and 2011-2012, except for a significant decline among children aged 2 to 5 years. OBJECTIVES To provide estimates of obesity and extreme obesity prevalence for children and adolescents for 2011-2014 and investigate trends by age between 1988-1994 and 2013-2014. DESIGN, SETTING, AND PARTICIPANTS Children and adolescents aged 2 to 19 years with measured weight and height in the 1988-1994 through 2013-2014 National Health and Nutrition Examination Surveys. EXPOSURES Survey period. MAIN OUTCOMES AND MEASURES Obesity was defined as a body mass index (BMI) at or above the sex-specific 95th percentile on the US Centers for Disease Control and Prevention (CDC) BMI-for-age growth charts. Extreme obesity was defined as a BMI at or above 120% of the sex-specific 95th percentile on the CDC BMI-for-age growth charts. Detailed estimates are presented for 2011-2014. The analyses of linear and quadratic trends in prevalence were conducted using 9 survey periods. Trend analyses between 2005-2006 and 2013-2014 also were conducted. RESULTS Measurements from 40,780 children and adolescents (mean age, 11.0 years; 48.8% female) between 1988-1994 and 2013-2014 were analyzed. Among children and adolescents aged 2 to 19 years, the prevalence of obesity in 2011-2014 was 17.0% (95% CI, 15.5%-18.6%) and extreme obesity was 5.8% (95% CI, 4.9%-6.8%). Among children aged 2 to 5 years, obesity increased from 7.2% (95% CI, 5.8%-8.8%) in 1988-1994 to 13.9% (95% CI, 10.7%-17.7%) (P < .001) in 2003-2004 and then decreased to 9.4% (95% CI, 6.8%-12.6%) (P = .03) in 2013-2014. Among children aged 6 to 11 years, obesity increased from 11.3% (95% CI, 9.4%-13.4%) in 1988-1994 to 19.6% (95% CI, 17.1%-22.4%) (P < .001) in 2007-2008, and then did not change (2013-2014: 17.4% [95% CI, 13.8%-21.4%]; P = .44). Obesity increased among adolescents aged 12 to 19 years between 1988-1994 (10.5% [95% CI, 8.8%-12.5%]) and 2013-2014 (20.6% [95% CI, 16.2%-25.6%]; P < .001) as did extreme obesity among children aged 6 to 11 years (3.6% [95% CI, 2.5%-5.0%] in 1988-1994 to 4.3% [95% CI, 3.0%-6.1%] in 2013-2014; P = .02) and adolescents aged 12 to 19 years (2.6% [95% CI, 1.7%-3.9%] in 1988-1994 to 9.1% [95% CI, 7.0%-11.5%] in 2013-2014; P < .001). No significant trends were observed between 2005-2006 and 2013-2014 (P value range, .09-.87). CONCLUSIONS AND RELEVANCE In this nationally representative study of US children and adolescents aged 2 to 19 years, the prevalence of obesity in 2011-2014 was 17.0% and extreme obesity was 5.8%. Between 1988-1994 and 2013-2014, the prevalence of obesity increased until 2003-2004 and then decreased in children aged 2 to 5 years, increased until 2007-2008 and then leveled off in children aged 6 to 11 years, and increased among adolescents aged 12 to 19 years.

Trends in sugar-sweetened beverage consumption among youth and adults in the United States: 1999–2010

BACKGROUND Reducing sugar-sweetened beverage (SSB) consumption is a recommended strategy to promote optimal health. OBJECTIVE The objective was to describe trends in SSB consumption among youth and adults in the United States. DESIGN We analyzed energy intake from SSBs among 22,367 youth aged 2-19 y and 29,133 adults aged ≥20 y who participated in a 24-h dietary recall as part of NHANES, a nationally representative sample of the US population with a cross-sectional design, between 1999 and 2010. SSBs included soda, fruit drinks, sports and energy drinks, sweetened coffee and tea, and other sweetened beverages. Patterns of SSB consumption, including location of consumption and meal occasion associated with consumption, were also examined. RESULTS In 2009-2010, youth consumed a mean (±SE) of 155 ± 7 kcal/d from SSBs, and adults consumed an age-adjusted mean (±SE) of 151 ± 5 kcal/d from SSBs--a decrease from 1999 to 2000 of 68 kcal/d and 45 kcal/d, respectively (P-trend < 0.001 for each). In 2009-2010, SSBs contributed 8.0% ± 0.4% and 6.9% ± 0.2% of daily energy intake among youth and adults, respectively, which reflected a decrease compared with 1999-2000 (P-trend < 0.001 for both). Decreases in SSB consumption, both in the home and away from home and also with both meals and snacks, occurred over the 12-y study duration (P-trend < 0.01 for each). CONCLUSION A decrease in SSB consumption among youth and adults in the United States was observed between 1999 and 2010.

Trends in Lipids and Lipoproteins in US Adults, 1988-2010

CONTEXT Serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) contribute to atherosclerosis and its clinical consequences. Between the periods 1988-1994 and 1999-2002, mean TC and mean LDL-C declined in adults. During this time, there was an increase in the percentage of adults receiving lipid-lowering medications. Geometric mean triglyceride levels increased but mean high-density lipoprotein cholesterol (HDL-C) remained unchanged. OBJECTIVE To examine trends in serum lipids in adults between 1988 and 2010. DESIGN, SETTING, AND PARTICIPANTS Three distinct US cross-sectional National Health and Nutrition Examination Surveys, 1988-1994 (n = 16,573), 1999-2002 (n = 9471), and 2007-2010 (n = 11,766). MAIN OUTCOME MEASURES Mean TC, LDL-C, HDL-C, non-HDL-C, and geometric mean triglyceride levels and the prevalence of lipid-lowering medication use. RESULTS Mean TC declined from 206 (95% CI, 205-207) mg/dL in 1988-1994 to 196 (95% CI, 195-198) mg/dL in 2007-2010 (P <.001 for linear trend); mean LDL-C declined from 129 (95% CI, 127-130) mg/dL to 116 (95% CI, 114-117) mg/dL (P <.001 for linear trend). Mean non-HDL-C declined from 155 (95% CI, 153-157) mg/dL in 1988-1994 to 144 (95% CI, 143-145) mg/dL in 2007-2010 (P <.001 for linear trend). Mean HDL-C increased from 50.7 (95% CI, 50.0-51.0) mg/dL during 1988-1994 to 52.5 (95% CI, 51.8-53.2) mg/dL in 2007-2010 (P =.001 for linear trend). Geometric mean serum triglyceride levels increased from 118 (95% CI, 114-121) mg/dL in 1988-1994 to 123 (95% CI, 119-127) mg/dL in 1999-2002 and decreased to 110 (95% CI, 107-113) mg/dL in 2007-2010 (P <.001 for quadratic trend). The prevalence of lipid-lowering medication use increased from 3.4% (95% CI, 2.9%-3.9%) in 1988-1994 to 15.5% (95% CI, 14.7%-16.3%) in 2007-2010 (P <.001 for linear trend). Among adults not receiving lipid-lowering medications, trends in lipids were similar to those reported for adults overall. Among obese adults, mean TC, non-HDL-C, LDL-C, and geometric mean triglycerides declined between 1988 and 2010. CONCLUSION Between 1988 and 2010, favorable trends in lipid levels have occurred among adults in the United States.

Prevalence of and Trends in Dyslipidemia and Blood Pressure Among US Children and Adolescents, 1999-2012

IMPORTANCE Recent national data suggest there were improvements in serum lipid concentrations among US children and adolescents between 1988 and 2010 but an increase in or stable blood pressure (BP) during a similar period. OBJECTIVE To describe the prevalence of and trends in dyslipidemia and adverse BP among US children and adolescents. DESIGN The National Health and Nutrition Examination Survey, a cross-sectional survey. SETTING Noninstitutionalized US population. PARTICIPANTS Children and adolescents aged 8 to 17 years with measured lipid concentrations (n = 1482) and BP (n = 1665). MAIN OUTCOMES AND MEASURES Adverse concentrations of total cholesterol (TC) (≥ 200 mg/dL), high-density lipoprotein cholesterol (HDL-C) (<40 mg/dL), and non-HDL-C (≥ 145 mg/dL) (to convert TC, HDL-C, and non-HDL-C to millimoles per liter, multiply by 0.0259) and high or borderline BP were examined. Definitions of BP were informed by the Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents by the National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents. Analyses of linear trends in dyslipidemias and BP were conducted overall and separately by sex across 7 periods (1999-2000, 2001-2002, 2003-2004, 2005-2006, 2007-2008, 2009-2010, and 2011-2012). RESULTS In 2011-2012, 20.2% (95% CI, 16.3-24.6) of youths had an adverse concentration of TC, HDL-C, or non-HDL-C and 11.0% (95% CI, 8.8-13.4) had either high or borderline BP. The prevalences of adverse concentrations decreased between 1999-2000 and 2011-2012 for TC (10.6% [95% CI, 8.3-13.2] vs 7.8% [95% CI, 5.7-10.4]; P = .006), HDL-C (17.9% [95% CI, 15.0-21.0] vs 12.8% [95% CI, 9.8-16.2]; P = .003), and non-HDL-C (13.6% [95% CI, 11.3-16.2] vs 8.4% [95% CI, 5.9-11.5]; P < .001). There was a decrease in high BP between 1999-2000 (3.0% [95% CI, 2.0-4.3]) and 2011-2012 (1.6% [95% CI, 1.0-2.4]) (P = .003). There was no change from 1999-2000 to 2011-2012 in borderline high BP (7.6% [95% CI, 5.8-9.8] vs 9.4% [95% CI, 7.2-11.9]; P = .90) or either high or borderline high BP (10.6% [8.4-13.1] vs 11.0% [95% CI, 8.8-13.4]; P = .26). CONCLUSIONS AND RELEVANCE In 2011-2012, approximately 1 in 5 children and adolescents aged 8 to 17 years had an adverse lipid concentration of TC, HDL-C, or non-HDL-C and slightly more than 1 in 10 had either borderline high or high BP. The prevalence of dyslipidemia modestly decreased between 1999-2000 and 2011-2012, but either high or borderline high BP remained stable. The reasons for these trends require further study.

Trends in Serum Lipids Among US Youths Aged 6 to 19 Years, 1988-2010

CONTEXT For more than 20 years, primary prevention of coronary heart disease has included strategies intended to improve overall serum lipid concentrations among youths. OBJECTIVE To examine trends in lipid concentrations among youths from 1988-1994 through 2007-2010. DESIGN, SETTING, AND PARTICIPANTS Cross-sectional analysis of serum lipid concentrations among 16,116 youths aged 6 to 19 years who participated in the nationally representative National Health and Nutrition Examination Survey during 3 time periods: 1988-1994, 1999-2002, and 2007-2010. MAIN OUTCOME MEASURES Among all youths, mean serum total cholesterol (TC), non-high-density lipoprotein cholesterol (non-HDL-C), high-density lipoprotein cholesterol (HDL-C); and among adolescents only, low-density lipoprotein cholesterol (LDL-C) and geometric mean triglyceride levels. Trends in adverse lipid concentrations are reported for TC levels of 200 mg/dL and greater, non-HDL-C levels of 145 mg/dL and greater, HDL-C levels of less than 40 mg/dL, LDL-C levels of 130 mg/dL and greater, and triglyceride levels of 130 mg/dL and greater. RESULTS Among youths aged 6 to 19 years between 1988-1994 and 2007-2010, there was a decrease in mean TC (from 165 mg/dL [95% CI, 164-167] to 160 mg/dL [95% CI, 158-161]; P < .001) and a decrease in the prevalence of elevated TC (from 11.3% [95% CI, 9.8%-12.7%] to 8.1% [95% CI, 6.7%-9.5%]; P = .002). Mean HDL-C significantly increased between 1988-1994 and 2007-2010, but the prevalence of low HDL-C did not change. Mean non-HDL-C and prevalence of elevated non-HDL-C both significantly decreased over the study period. In 2007-2010, 22% (95% CI, 20.3%-23.6%) of youths had either a low HDL-C level or high non-HDL-C, which was lower than the 27.2% (95% CI, 24.6%-29.7%) in 1988-1994 (P = .001). Among adolescents (aged 12-19 years) between 1988-1994 and 2007-2010, there was a decrease in mean LDL-C (from 95 mg/dL [95% CI, 92-98] to 90 mg/dL [95% CI, 88-91]; P = .003) and a decrease in geometric mean triglycerides (from 82 mg/dL [95% CI, 78-86] to 73 mg/dL [95% CI, 70-76]; P < .001). Prevalence of elevated LDL-C and triglycerides between 1988-1994 and 2007-2010 also significantly decreased. CONCLUSIONS Between 1988-1994 and 2007-2010, a favorable trend in serum lipid concentrations was observed among youths in the United States but almost 1 in 10 had elevated TC in 2007-2010.

Impact of environmental tobacco smoke on children with asthma, United States, 2003-2010.

OBJECTIVE Given widespread interventions to reduce environmental tobacco smoke (ETS) exposure and improve asthma control, we sought to assess the current impact of ETS exposure on children with asthma. METHODS We analyzed 2003-2010 data for nonsmoking children aged 6 to 19 years with asthma from the National Health and Nutrition Examination Survey. Outcomes (sleep disturbance, missed school days, health care visits, activity limitation, and wheezing with exercise) were compared between ETS exposed children (serum cotinine levels 0.05 to 10 ng/mL) and unexposed children (<0.05 ng/mL) using ordinal regression adjusted for demographic characteristics. We also assessed whether associations were observable with low ETS exposure levels (0.05 to 1.0 ng/mL). RESULTS Overall, 53.3% of children aged 6 to 19 years with asthma were ETS exposed. Age-stratified models showed associations between ETS exposure and most adverse outcomes among 6- to 11-year-olds, but not 12- to 19-year-olds. Even ETS exposure associated with low serum cotinine levels was associated with adverse outcomes for 6- to 11-year-olds. Race-stratified models for children aged 6 to 19 years showed an association between ETS exposure and missing school, health care visits, and activity limitation due to wheezing among non-Hispanic white children, and disturbed sleep among non-Hispanic white and Mexican children. Among non-Hispanic black children, there was no elevated risk between ETS exposure and the assessed outcomes: non-Hispanic black children had high rates of adverse outcomes regardless of ETS exposure. CONCLUSIONS Among children with asthma 6 to 11 years of age, ETS exposure was associated with most adverse outcomes. Even ETS exposure resulting in low serum cotinine levels was associated with risks for young children with asthma.

Prescription Medication Use Among Normal Weight, Overweight, and Obese Adults, United States, 2005–2008

PURPOSE We sought to describe differences between normal weight, overweight, and obese adults in use of specific prescription medication classes. METHODS Cross-sectional analysis of prescription medication use among 9789 adults in the National Health and Nutrition Examination Survey, a nationally representative sample of the United States. RESULTS In 2005-2008, 56.4% (95% confidence interval [CI], 54.6-58.3) of adults used 1+ prescription medication. Approximately one-quarter of adults used a hypertension medication (26.1%; 95% CI, 24.5%-27.8%). The use of hypertension medications increased with increasing weight status (normal weight: 17.2%; 95% CI, 15.6%-18.8%; overweight: 24.5%, 95% CI, 22.6%-26.4%; and obese: 35.1%, 95% CI, 32.8%-37.4%). Similarly, lipid-lowering, analgesic, antidepressant, proton pump inhibitors, thyroid, diabetes, and bronchodilator medication use was greater among obese compared with normal weight adults (each p < .01). Among adults 65+ years, 72% (95% CI, 68.2%-75.8%) of men and 67.7% (95% CI, 64.3%-71.2%) of women used a hypertension medication and a majority of men (51.2%, 95% CI, 48.4%-54%) and 40.3% (95% CI, 36.8%-43.8%) of women used lipid lowering medications; the use of both was greater among obese adults compared to normal weight adults (both p < .01). CONCLUSIONS Obese adults in the United States use several prescription medication classes more frequently, than normal weight adults, including hypertension, lipid-lowering, and diabetes medications.

Seafood consumption and blood mercury concentrations in adults aged ≥20 y, 2007–2010

BACKGROUND Seafood is part of a healthy diet, but seafood can also contain methyl mercury-a neurotoxin. OBJECTIVE The objective was to describe seafood consumption in US adults and to explore the relation between seafood consumption and blood mercury. DESIGN Seafood consumption, obtained from a food-frequency questionnaire, and blood mercury data were available for 10,673 adults who participated in the 2007-2010 NHANES-a cross-sectional nationally representative sample of the US population. Seafood consumption was categorized by type (fish or shellfish) and by frequency of consumption (0, 1-2, 3-4, or ≥5 times/mo). Linear trends in geometric mean blood mercury concentrations by frequency of seafood consumption were tested. Logistic regression analyses examined the odds of blood mercury concentrations ≥5.8 μg/L (as identified by the National Research Council) based on frequency of the specific type of seafood consumed (included in the model as continuous variables) adjusted for sex, age, and race/Hispanic origin. RESULTS In 2007-2010, 83.0% ± 0.7% (±SE) of adults consumed seafood in the preceding month. In adults consuming seafood, the blood mercury concentration increased as the frequency of seafood consumption increased (P < 0.001). In 2007-2010, 4.6% ± 0.39% of adults had blood mercury concentrations ≥5.8 μg/L. Results of the logistic regression on blood mercury concentrations ≥5.8 μg/L showed no association with shrimp (P = 0.21) or crab (P = 0.48) consumption and a highly significant positive association with consumption of high-mercury fish (adjusted OR per unit monthly consumption: 4.58; 95% CI: 2.44, 8.62; P < 0.001), tuna (adjusted OR: 1.14; 95% CI: 1.10, 1.17; P < 0.001), salmon (adjusted OR: 1.14; 95% CI: 1.09, 1.20; P < 0.001), and other seafood (adjusted OR: 1.12; 95% CI: 1.08, 1.15; P < 0.001). CONCLUSION Most US adults consume seafood, and the blood mercury concentration is associated with the consumption of tuna, salmon, high-mercury fish, and other seafood.