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Sugar-Sweetened Beverages, Serum Uric Acid, and Blood Pressurein Adolescents

STEPHANIE NGUYEN, MD, HYON K. CHOI, MD, DRPH, ROBERT H. LUSTIG, MD, AND CHI-YUAN HSU, MD, MSC

bjective To evaluate whether sugar-sweetened beverage consumption, a significant source of dietary fructose, is associatedith higher serum uric acid levels and blood pressure in adolescents.

tudy design We analyzed cross-sectional data from 4867 adolescents aged 12 to 18 years in the National Health andutrition Examination Survey, 1999-2004. Dietary data were assessed from 24-hour dietary recall interviews. Sugar-sweetenedeverages included fruit drinks, sports drinks, soda, and sweetened coffee or tea. We used multivariate linear regression tovaluate the association of sugar-sweetened beverage consumption with serum uric acid and with blood pressure.

esults Adolescents who drank more sugar-sweetened beverages tended to be older and male. In the adjusted model, serumric acid increased by 0.18 mg/dL and systolic blood pressure z-score increased by 0.17 from the lowest to the highest categoryf sugar-sweetened beverage consumption (P for trend, .01 and .03, respectively).

onclusions These results from a nationally representative sample of US adolescents indicate that higher sugar-sweetenedeverage consumption is associated with higher serum uric acid levels and systolic blood pressure, which may lead toownstream adverse health outcomes. (J Pediatr 2009;154:807-13)

ince its introduction into the US food supply in the 1970s, high fructose corn syrup has become the most popularsweetener used in processed foods, especially in beverages such as sodas and fruit drinks.1 Fructose, unlike glucose or othermonosaccharide sugars, is solely metabolized in the liver, where it induces nucleotide catabolism, thereby producing uric

cid.2,3 Human studies confirm that experimental fructose feeding or intravenous fructose administration raises serum uric acidevels.4-7 This may be important because serum uric acid has been suggested to be a

arker of cardiovascular disease risk8 and a potential intermediate step toward theevelopment of hypertension.9

Sugar-sweetened beverages are a significant source of calories for adolescents,ontributing 301 kilocalories per day or 13% of total daily energy.10 Two previouspidemiologic studies in adults have shown that sugar-sweetened beverage consumptions associated with higher serum uric acid levels.11,12 Although sugar-sweetened beverageonsumption has been associated with obesity in children and adolescents,13 it is unknownow sugar-sweetened beverage consumption is independently associated with serum uriccid levels in adolescents. In addition, even though uric acid has been positively associatedith blood pressure elevation and primary hypertension in children,14-17 it is unknown how

ugar-sweetened beverage consumption is associated with blood pressure level in adolescents.The goal of this study was to evaluate whether the consumption of sugar-sweetened

everages is associated with higher serum uric acid levels and with higher blood pressure,n a nationally representative sample of adolescents.

METHODSThis is a cross-sectional study using data from the National Health and Nutrition

xamination Survey (NHANES) 1999-2004, a complex sample survey designed to collectata on the health and nutrition from a representative household population in the Unitedtates.18 Certain populations, such as adolescents and racial/ethnic minorities, wereversampled to improve estimates in these groups.

MI Body mass index NHANES National Health and Nutrition Examination

See editorial, p 783

From the Department of Pediatrics (S.N.,R.L.), University of California San Francisco,San Francisco, CA, Arthritis Research Centreof Canada, Vancouver General Hospital andthe University of British Columbia, Vancou-ver, British Columbia, Canada; Brigham andWomen’s Hospital, Boston, MA (H.C.); andDepartment of Medicine (C.H.), University ofCalifornia, San Francisco, CA.

S.N. was supported by the American HeartAssociation (0725258Y) and the Depart-ment of Pediatrics, University of CaliforniaSan Francisco. C-y.H. was supported byNIH DK70939 and DK67126.

The authors disclose no conflicts of interest.

Submitted for publication Aug 29, 2008;last revision received Nov 25, 2008; ac-cepted Jan 9, 2009.

Reprint requests: Dr Stephanie Nguyen,UCSF Children’s Renal Center, 533 ParnassusAvenue, Box 0748, San Francisco, CA 94131-0748. E-mail: nguyens@peds.ucsf.edu.

0022-3476/$ - see front matter

Copyright © 2009 Mosby Inc. All rightsreserved.

Survey

10.1016/j.jpeds.2009.01.015

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The NHANES protocol was reviewed and approved byhe National Center for Health Statistic’s Institutional Re-iew Board. Informed consent and assent were obtained,here appropriate, from all participants before any studyrocedure.

There were 4938 adolescents aged 12 to 18 years withietary intake data and serum uric acid levels measured inHANES 1999-2004. We excluded pregnant adolescents

n � 71). Thus, there were 4867 adolescents available for thisnalysis.

In NHANES 1999-2004, information on race/ethnic-ty (non-Hispanic white, non-Hispanic black, Hispanic, orther), medical history, and medication usage was collected byelf-report in a standardized in-home medical interview. In-ormation on age, weight, height, body mass index (BMI),nd blood pressure was determined at the time of the physicalxamination component of the survey. Blood pressure waseasured using a mercury sphygmomanometer, using themerican Heart Association guidelines.19 Up to 4 bloodressure measurements were taken. When more than 1 bloodressure measurement was available, the average systolic andiastolic blood pressure measurements were calculated. Theystolic or diastolic blood pressure z-score was calculatedased on the subject’s age, height, and sex. Smoking statusas determined by a self-reported history of smoking in therevious 5 days, or a serum cotinine level (a metabolite oficotine) �15 ng/mL.20

Twenty-four-hour dietary recall interviews were admin-stered at the time of the physical examination component ofhe survey using a computer-assisted dietary interview systemith multiple-pass format and standardized probes. Botheekdays and weekend days were sampled. Dietary informa-

ion was available from 3 data sets: the total nutrients file, thendividual food files, and the pyramid servings intake data for

HANES. The NHANES total nutrient intake files pro-ided dietary fiber intake, sodium intake, caffeine intake, andotal calories. The individual food files provided alcohol in-ake and individual food items, which were analyzed by theirSDA food code. Sugar-sweetened beverages included fruitrinks, soft drinks, sports drinks, reconstituted powders (eg,ool-aid, Tang), and sweetened coffee or tea. Juices includednsweetened fruit juice or nectar. Diet beverages includedoncaloric beverages such as diet sodas, coffee or tea withoutweeteners, and low-calorie drinks. Milk beverages includedows milk, buttermilk, goat’s milk, and reconstituted milk.he pyramid serving intake data provided information on theumber of servings per day of fruit, vegetables, dairy, meat,nd seafood.

Serum uric acid levels were measured by a colorimetricethod whereby uric acid is oxidized by uricase to allantoin

nd hydrogen peroxide. Details about quality-control proce-ures have been published elsewhere.21 Values are reported inilligrams per deciliter (to convert to micromoles per liter,ultiply by 59.48).

Beverage consumption was categorized on the basis of

eadily understood serving sizes (12 ounces is equivalent to 1 s

08 Nguyen et al

an of soda and 8 ounces is equivalent to 1 serving size of milkr juice), distribution of the data, and to ensure sufficientample size.18 Sugar-sweetened beverage consumption wasategorized by number of ounces consumed per day (0 oz/d,to 12 oz/d, 13 to 24 oz/d, 25 to 36 oz/d, or �36 oz/d).

uices were categorized by number of ounces consumed peray (0 oz/d, 1 to 8 oz/d, 9 to 16 oz/d, or �16 oz/d). Dieteverage consumption was categorized by number of ouncesonsumed per day (0 oz/d, 1 to 12 oz/d, or �12 oz/d). Milkeverage consumption was categorized by number of ouncesonsumed per day (0 oz/d, 1 to 8 oz/d, 9 to 16 oz/d, or �16z/d).

All statistical analyses were completed using STATAversion 9.0 StataCorp; College Station, Texas), taking intoccount samples’ weights, strata, and primary sampling unitsrom NHANES 1999-2004 to adjust for unequal probabili-ies of selection and the multistage stratified sample design.22

he weighted proportions were used to extrapolate to thedolescent US population using 2000 US Census counts.inear test for trend was reported for categories of beverageonsumption.

We used linear regression models to evaluate the asso-iation of sugar-sweetened beverage consumption categoriesith serum uric acid levels and with blood pressure.

We explored the following potential confounding vari-bles: age (years), race/ethnicity, sex, BMI z-scores, height,-scores, total calories (kcal/d), smoking, alcohol (�50 g/d),ruit (servings/d), dairy (servings/d), meat and seafood (serv-ngs/d), dietary fiber intake (g/d), caffeine intake (mg/d),odium intake (mg/d), milk consumption, and diet beverageonsumption. Our initial linear regression models adjusted forasic clinical and demographic variables: age, race/ethnicity,ex, BMI z-score, and total calories simultaneously. Con-ounding variables chosen for our final linear regression modelet at least 1 of the following criteria: variables with P � .20

r those that changed the coefficient �10%. The final modelor serum uric acid and sugar-sweetened beverage consump-ion simultaneously adjusted for age, race/ethnicity, sex, BMI-score, total calories, smoking, alcohol, dietary fiber intake,ilk, and diet beverage consumption. The final model for

ystolic blood pressure Z-scores simultaneously adjusted forge, race/ethnicity, sex, BMI Z-score, height Z-score, totalalories, smoking, alcohol, caffeine, sodium, and milk con-umption. The final model for diastolic blood pressure Z-cores simultaneously adjusted for age, race/ethnicity, sex,MI Z-score, total calories, smoking, alcohol, and sodium

ntake.To evaluate for potential interactions by sex and obesity

BMI �95th percentile for sex and age) on the association ofeverage consumption with serum uric acid and blood pres-ure, we added interaction terms for sex and obesity to thenadjusted and fully adjusted models. Interaction terms with� .20 were designated a priori as significant.

We performed sensitivity analysis by excluding adoles-ents who reported taking antihypertensive medications, as

ome antihypertensive medications can affect serum uric acid

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evels. We performed sensitivity analysis by including un-weetened fruit juices in the category of sugar-sweetenedeverages, as fruit juices include naturally occurring fructose.

e also performed a sensitivity analysis by excluding sweet-ned coffee or tea in the category of sugar-sweetened bever-ges, as some sweetened coffee or tea may include drinksweetened with sucrose.

RESULTSDemographic and clinical characteristics of the study

opulation are shown in Table I. Drinking any amount ofugar-sweetened beverages in a day was reported by 82.5% ofdolescents. Adolescents who drank more sugar-sweetenedeverages tended to be older and male. Sugar-sweetenedeverage consumption did not differ according to race/eth-icity, BMI z-score, height z-score, or dietary fiber intake.ugar-sweetened beverage consumption was associated withigher intake of total calories, sodium, and caffeine. Sugar-weetened beverage consumption was associated with lessilk and diet beverage consumption. Adolescents in the

ighest category of sugar-sweetened beverage consumption

able I. Demographic and clinical characteristics byn adolescents 12 to 18 years of age in the NHANES

Categori

Overall 0

† 4867 774‡ 17.4%ge, median, y 15.5 15.4oys, % 52.1% 43.3%ace/ethnicity, %White 63.5% 67.5%Black 15.1% 12.3%Hispanic 16.6% 14.8%Other 4.8% 5.4%

MI z-score, median 0.48 0.42eight z-score, median 0.13 0.12otal calories, median, kcal/d 2172 1915.7ietary fiber, median. g/d 11.9 12.6

odium, median, mg/d 3150 2946affeine, median, mg/d 37 2.5ilk, oz/d�1 46.8% 42.8%1-8 10.8% 11.0%9-16 22.2% 19.1%�16 20.2% 27.1%iet beverages, oz/d�1 83.6% 67.8%1-12 5.8% 9.2%�12 10.6% 23.0%

moking, % 15.1% 10.9%lcohol, % 1.3% 1.0%

P for trend.Raw number of adolescents in study population not adjusted for sample survey designExcept where otherwise noted, data shown are adjusted for the complex sample surve

ere more likely to smoke and to drink alcohol than adoles- t

ugar-Sweetened Beverages, Serum Uric Acid, and Blood Pressure in Ad

ents in the lowest categories of sugar-sweetened beverageonsumption.

The association of sugar-sweetened beverage consump-ion with serum uric acid levels is shown in Table II. In thenadjusted model, serum uric acid levels increased by 0.50g/dL in adolescents in the highest category of sugar-sweet-

ned beverage consumption compared with adolescents in theowest category of sugar-sweetened beverage consumption. Inhe adjusted model (Table II, Model 1), increasing sugar-weetened beverage consumption was associated with highererum uric acid levels. However, in the model additionallydjusted for alcohol, smoking, dietary fiber, milk, and dieteverage consumption (Table II, Model 2), serum uric acidevels increased by only 0.18 mg/dL in adolescents in theighest category of sugar-sweetened beverage consumptionompared with adolescents in the lowest category of sugar-weetened beverage consumption (P for trend � .01) (Fig-re). We found that the correlation of sugar-sweetened bev-rage consumption with serum uric acid levels was notodified by sex or obesity (P for interaction �.2 each).

The association of sugar-sweetened beverage consump-

gories of sugar-sweetened beverage consumption9-2004 study

sugar-sweetened beverage intake (oz/d)

P*12 13-24 25-36 >36

9 1410 916 11989.6% 27.6% 18.1% 27.3%4.6 15.0 15.3 16.4 �.00016.9% 50.5% 54.3% 63.3% �.0001

3.6% 60.9% 63.3% 67.1% 0.421.3% 16.8% 15.6% 12.7%0.5% 18.0% 16.7% 15.0%4.6% 4.4% 4.5% 5.2%0.51 0.50 0.38 0.51 .550.11 0.22 0.07 0.20 .081.0 2049.5 2249.0 2673.0 �.00010.5 11.5 11.6 12.6 .152 2886 3080 3739 �.00018.0 34.9 56.2 105.0 �.0001

5.2% 41.7% 45.7% 55.6% .00023.2% 11.4% 10.0% 9.7%5.5% 24.9% 25.9% 18.0%6.1% 22.0% 18.4% 16.7%

3.4% 81.5% 91.1% 90.8% �.00017.7% 6.9% 3.5% 3.3%8.9% 11.6% 5.4% 5.9%9.6% 11.1% 16.4% 23.1% �.00010.1% 1.1% 0.9% 2.6% .003

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ion with systolic blood pressure z-score is shown in Table III.

olescents 809

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n the unadjusted model, higher sugar-sweetened beverageonsumption was not significantly associated with higher sys-olic blood pressure z-score. However, when adjusted for age,ace/ethnicity, sex, total calories, and BMI z-score, sugar-weetened beverage consumption was associated with higherystolic blood pressure, a z-score difference of 0.18 (Table III,

odel 1). Both age and total calories were positively associ-ted with sugar-sweetened beverage consumption but nega-ively associated with systolic blood pressure z-score (data nothown), and therefore masked the association in the unad-usted model. In the model additionally adjusted for height-score, sodium, caffeine, smoking, alcohol, and milk con-umption (Table III, Model 2), sugar-sweetened beverageonsumption was associated with higher systolic blood pres-ure, a z-score difference of 0.17 (P for trend � .03). Thereas no association between sugar-sweetened beverage con-

umption with diastolic blood pressure z-score in the unad-usted or adjusted models (Table III). We found that theorrelation of sugar-sweetened beverage consumption withlood pressure was not modified by sex or obesity (P for

able II. Difference in serum uric acid according to cric acid (mg/dL)

SSB (oz/d)Unadjusteddifference 95% CI Adjusted di

Reference Referen-12 �0.18 �0.38, 0.03 0.023-24 0.10 �0.06, 0.26 0.055-36 0.25 0.08, 0.41 0.1636 0.50 0.35, 0.65 0.22for trend �.00001 0.002

SB, Sugar-sweetened beverage.Model adjusted for age, race/ethnicity, sex, total calories, and BMI z-score.Model adjusted for age, race/ethnicity, sex, total calories, BMI z-score, alcohol, smok

igure. Sample mean of serum uric acid with 95% confidence intervals byategories of sugar-sweetened beverage consumption adjusted for age, race/thnicity, sex, total calories, BMI z-score, alcohol, smoking, dietary fiberntake, diet beverage consumption, and milk consumption. P for trend � .01.

nteraction �.2 each). t

10 Nguyen et al

There were 3458 (73.4%), 330 (5.4%), 622 (11.9%), and57 (9.3%) adolescents who reported drinking 0 oz/d, 1 to 8z/d, 9 to 16 oz/d, and �16 oz/d of fruit juice, respectively.ruit juice consumption was not independently associatedith serum uric acid or blood pressure. When fruit juices were

ncluded with sugar-sweetened beverages, we observed a sim-lar association between sugar-sweetened beverage consump-ion with serum uric acid and diastolic blood pressure. Whenruit juices were included with sugar-sweetened beverages, webserved a similar effect size between sugar-sweetened bev-rage consumption and systolic blood pressure; however, itid not reach conventional levels of statistical significance.

When sweetened coffee or tea was excluded from theugar-sweetened beverage category, there were 879 (19.7%),87 (10.1%), 1437 (28.8%), 886 (17.5%), and 1078 (23.9%)dolescents who reported drinking 0 oz/d, 1 to 12 oz/d, 13 to4 oz/d, 25 to 36 oz/d, or �36 oz/d of sugar-sweetenedeverages. After exclusion of sweetened coffee or teas, webserved a similar association between sugar-sweetened bev-rage consumption with serum uric acid, systolic blood pres-ure, and diastolic blood pressure.

There were 17 adolescents in our sample who reportedaking antihypertensive medications. When they were ex-luded from our analysis, we observed similar associationsetween sugar-sweetened beverage consumption with serumric acid and blood pressure.

We did not exclude adolescents with chronic kidneyisease because only 61% of adolescents had a serum creati-ine level measured. However, in the subset of adolescentsho had a serum creatinine measured, there were 11 adoles-

ent with an estimated glomerular filtration rate �90 mL/miner 1.73m2 and none less than 60 mL/min per 1.73 m2.23 Weid not exclude adolescents who took medications (allopuri-ol and probenecid) that affect uric acid levels because pre-cription medications were not recorded for adolescents 16ears old or younger. However, in the subset of adolescentsetween 16 and 18 years old who had prescription medica-ions recorded, there were no adolescents who took medica-

gories of sugar-sweetened beverage consumption

del 1* Model 2‡

nce 95% CI Adjusted difference 95% CI

Reference�0.20, 0.23 0.03 �0.19, 0.24�0.09, 0.20 0.05 �0.10, 0.20

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DISCUSSIONAdult studies have shown serum uric acid levels to be

redictive of major outcomes even when values are within theormal range.8

It should be noted that the adjusted difference in serumric acid between the lowest and highest category of sugar-weetened beverage consumption was relatively small. In adulttudies, the risk associated with serum uric acid varies with theutcome. The observed serum uric acid difference betweenxtreme categories, 0.18 mg/dL, in the NHANES III, wasssociated with an 50% increased risk of incident gout in aarge prospective adult cohort study.11,24 On the other hand,or every 1 mg/dL increase in serum uric acid, there was a 7%ncrease in the development of incident kidney disease oreath after adjusting for multiple variables such as age, sex,ace, systolic blood pressure, alcohol, smoking, HDL-choles-erol, and baseline kidney function.25

The mean systolic blood pressure z-score increased by.17 for the highest sugar-sweetened beverage category. Thisepresents a difference of 2 mm Hg (95% CI, 1 to 2 mm Hg).n a general normotensive adult population, a 2 mm Hgeduction of systolic blood pressure would lower stroke mor-ality by 10% and ischemic heart disease by 7%.26

Sugar-sweetened beverages are primarily sweetenedith high fructose corn syrup, a mixture of fructose andlucose.1 Unlike glucose, fructose is solely metabolized in the

able III. Difference in blood pressure z-scores accoronsumption

Systolic blood

SSB (oz/d)Unadjusteddifference 95% CI

Adi

Reference R-12 0.11 �0.02, 0.233-24 0.17 0.03, 0.315-36 0.10 0.00, 0.2036 0.14 0.00, 0.27for trend 0.08

Diastolic blood

SSB (oz/d)Unadjusteddifference 95% CI

Adi

Reference R-12 �0.03 �0.17, 0.113-24 �0.04 �0.16, 0.095-36 0.04 �0.08, 0.1736 �0.07 �0.18, 0.04for trend .64

SB, Sugar-sweetened beverage.Model adjusted for age, race/ethnicity, sex, total calories, and BMI z-score.Model adjusted for age, race/ethnicity, sex, total calories, BMI z-score, height z-scorModel adjusted for age, race/ethnicity, sex, total calories, BMI z-score, sodium intake

iver, where phosphorylation of fructose by fructokinase de- t

ugar-Sweetened Beverages, Serum Uric Acid, and Blood Pressure in Ad

letes intracellular phosphate. Activation of the enzyme AMPeaminase-1 increases adenine nucleotide catabolism, pro-ucing uric acid.27 Serum uric acid levels, even within theormal range, are associated with other cardiovascular riskactors and predict cardiovascular events in adults.8 Serumric acid levels have been associated with cardiovascular riskactors such as hypertension and the metabolic syndrome indolescents.14-17

We found that higher sugar-sweetened beverage con-umption was associated with higher systolic blood pressure indolescents. Our results are consistent with studies that sug-est that fructose consumption may contribute to the patho-enesis of hypertension through its action on serum uric acid.2

erum uric acid may raise systemic blood pressure by increas-ng renal inflammation, activating the renin-angiotensin sys-em, and decreasing nitric oxide production.28 Second, fruc-ose feeding can acutely decrease urinary sodium excretion,hereby potentially raising systemic blood pressure.29 Last,ugar-sweetened beverage consumption is associated with in-reased salt intake, which may contribute to higher bloodressure.30 In a referral based population, Feig et al15 foundhat children with primary hypertension had higher serumric acid than healthy control subjects. Using NHANES data,oldstein et al17 found that adolescents with higher serum

ric acid had higher blood pressure. In the Bogalusa Hearttudy,14 serum uric acid levels correlated with childhood sys-

to categories of sugar-sweetened beverage

ssure z-score

Model 1* Model 2†

ednce 95% CI

Adjusteddifference 95% CI

nce Reference�0.07, 0.19 0.02 �0.11, 0.15

0.01, 0.29 0.15 0.00, 0.290.00, 0.21 0.09 �0.03, 0.210.02, 0.34 0.17 0.02, 0.32

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Model 1* Model 2‡

ednce 95% CI

Adjusteddifference 95% CI

nce Reference5 �0.19, 0.09 �0.05 �0.18, 0.090 �0.13, 0.12 �0.01 �0.13, 0.120 �0.03, 0.22 0.10 �0.02, 0.235 �0.19, 0.09 0.04 �0.07, 0.169 0.09

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or age, sex, race, or BMI. Using the NHANES data, Ford etl16 found that adolescents in the highest tertile of serum uriccid levels were more likely to have high blood pressure andther components of the metabolic syndrome. In a cohort ofealthy adolescents, Savoca et al31 showed that those who hadore caffeinated soda consumption had higher systolic blood

ressure; however, these observations by were not adjusted forge, sex, BMI, caffeine intake, or smoking, thereby confound-ng their results.

The strength of this study is that it includes a nationallyepresentative population of adolescents, which increases gen-ralizability. The study population was also large and rigor-usly characterized, which allowed us to adjust for importantotential confounding factors, for which previous studies inhildren could not account, such as BMI, smoking, alcohol,affeine intake, and other dietary factors.

However, there are also limitations; 24-hour dietaryecall, although providing reliable population means for in-ake,32 is not the best tool to estimate the usual diet as it onlyssesses intake for 1 day. Food frequency questionnaires are aetter measure of long-term patterns of intake.33 We werenable to use the food frequency questionnaires for this studyecause the food frequency questionnaires in NHANES999-2002 did not include sugar-sweetened beverage con-umption.34 Random measurement errors from 24-hour di-tary recall would likely create a nondifferential form of mis-lassification bias, which will bias against finding anssociation between sugar-sweetened beverage consumptionnd uric acid. This misclassification bias may also diminishhe observed effect size of the sugar-sweetened beverage con-umption and systolic blood pressure association. At the sameime, the P value for trend in the sugar-sweetened beveragesnd systolic blood pressure association is very close to theonventional threshold for statistical significance so it is pos-ible that this is a false positive association due to chance.ata on family history of gout or hypertension were not

ollected in the NHANES surveys for participants youngerhan 20 years old. The effect of family history of gout andypertension could affect serum uric acid and systolic bloodressure through several potential pathways. Offspring ofypertensive parents have higher serum uric acid and lowerractional excretion of uric acid than offspring of normoten-ive parents.35,36 Second, offspring of hypertensive parentsave higher blood pressure.37,38 As families with gout orypertension may have shared environmental factors like di-tary patterns, family history may be a residual confoundingariable we were unable to account for in our analysis. Becausef the cross-sectional study design, we cannot demonstratehat it was the consumption of sugar-sweetened beverage thataised serum uric acid. However, it seems reasonable to as-ume that higher serum uric acid or systolic blood pressure didot cause adolescents to drink more sugar-sweetened bever-ges.

The current study provides new information on howugar-sweetened beverage consumption among adolescents

ay affect cardiovascular risk factors, namely serum uric acid

2s

12 Nguyen et al

nd blood pressure. Because this association does not appearo be modified by the presence or absence of obesity, our datauggest that reducing the sugar-sweetened beverage con-umption will have beneficial cardiovascular effects in adoles-ents, regardless of weight status.

he authors thank the following individuals for help with prep-ration and review of the manuscript: Eric Vittinghoff (NIH,mgen, Wyeth, and Berlex Labs), Michele Mietus-Snyder

American Heart Association), Paul Brakeman (NIH), and An-hony Portale (UCSF).

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