Cardiovascular Disease Risk Factor Changes in Schoolchildren, :

Transcription

1 Sex and Rae Differenes in Cardiovasular Disease Risk Fator Changes in Shoolhildren, : The Prineton Shool Study John A. Morrison, PhD, Frederik W James, MD, Dennis L. Spreher MD, Philip R. Khoury, MS, and Stephen R. Daniels, MD, PhD The deline in ardiovasular disease (CVD) mortality in the United States sine the 195s has been well doumented.' Several studies of adult populations have shown redutions in risk fators suh as high holesterol levels, blood pressure (BP), and smoking over the period of deline in CVD mortality, suggesting that muh of the derease in CVD mortality an be explained by improvement in risk fator status.23 Beause the genesis of atheroslerosis ours in hildhood, it is of interest to determine whether and to what degree CVD risk profiles have hanged in hildren over the period of deline in CVD mortality. Webber et al. reported an inrease in ponderal index over 6 ross-setional surveys onduted from to in Bogalusa, Louisiana, but no trends in blood lipid levels.4 The purpose ofthe present study was to evaluate hanges in CVD risk fators in shoolhildren in the Prineton (Ohio) Shool Distrit from to and to assess whether there were sex or rae differenes in the observed trends. The Prineton Shool Distrit is a geographially well defined suburban shool distrit in southwest Ohio, with a broad representation by rae and soioeonomi status. Sine the original National Heart, Lung, and Blood Institute (NHLBI) Lipid Researh Clinis (LR Prineton ohort ( )5-7 attended the same shools and lived in the same ommunities as did the students tested in , the latter students provide a useful omparison group for the study of temporal hanges in CVD risk fators. Methods The Prineton City Shool Distrit inludes 6 independent, inorporated ommunities plus uninorporated areas ofhamilton and Butler Counties in Ohio. It is loated approximately 15 miles north of the Cininnati Children's Hospital Medial Center. In 1973 the student population was 7% White and 29% Blak, while in 199 it was 62% White and 37% Blak. Census data reveal that the median household inomes in the Prineton Shool Distrit were omparable to those in the metropolitan Cininnati area in 197 and 199, indiating that the distrit did not hange soiodemographially during the study period. From 1973 through 1975, Prineton students partiipated in the LRC Program Prevalene Study.5-7 After a first visit in whih 84% of all students partiipated, a 15% random sample of partiipants was reruited for further study at a seond visit, at whih a fasting lipid profile was reorded, and resting heart rate (HR), blood pressure (BP), height, and weight were measured, and a 24-hour diet reall was obtained. Students in the random sample of the LRC visit-2 population whose ages fell between that ofthe youngest and oldest students in the sample (see below) were seleted for this omparison. In 1989 and 199, a new study was undertaken in the Prineton City Shool Distrit, targeting students in grades 3 and 5. Students had their height and weight, resting HR, BP, and plasma lipid profiles (total and highdensity lipoprotein holesterol [HDL-C] and triglyerides) measured. In addition, a 3-day John A. Morrison, Philip R. Khoury, and Stephen R. Daniels are, and at the time of the study Frederik W James was, with the Division of Cardiology, Department of Pediatris, University of Cininnati College of Mediine and Children's Hospital Medial Center, Cininnati, Ohio. Dennis L. Spreher is with the Department of Cardiology, The Cleveland Clini Foundation, Cleveland, Ohio. Correspondene and reprint requests should be sent to John A. Morrison, PhD, Children's Hospital Medial Center, 3333 Burnet Avenue, Cininnati, OH This artile was aepted Marh 17, November 1999, Vol. 89, No. 11

2 dietary reord was obtained for a sample of third- and fifth-grade students. Overall, 8% of the hildren had BPs measured and 63% had lipid profiles measured. As a means of determining whether the partiipating students differed from nonpartiipating students with respet to body mass, data on height and weight were obtained for all students as part of the shools' physial-fitness assessment, with the same equipment and proedures used to obtain these data for both groups. These omparisons revealed no signifiant differenes between partiipants and nonpartiipants. Both studies were approved by the appropriate institutional review board, with doumented informed onsent obtained from the parent or guardian before partiipation of subjets. Measurement Methods Similar methods were used in both studies: students were tested by shool and by grade and lass within shool, with the testing done at the shool and beginning about 1 minutes after the start of the shool day. Height and weight measurements were taken with students' shoes and outdoor lothing removed. In the LRC study, one measurement of height and weight was made aording to a standard proedure as previously desribed.8 In the seond study, 2 measurements ofheight and weight were made aording to a standard protool,9 and a third measurement was made if the first 2 differed by more than.5 m (height) or.3 kg (weight). In alulations and analyses, the mean of the reorded measurements was used. For eah ohort, the body mass index (BMI) (weight in kilograms divided by height in meters squared) was used as a measure of obesity. In the LRC study, 2 BP readings were reorded with a standard sphygmomanometer at the onset of the first and fifth Korotkoff phases, and a 15-seond measurement ofhr was reorded between these 2 readings, as previously desribed. 1 In , 3 readings of BP were made at the onset of the first, fourth, and fifth Korotkoff phases, following the NHLBI Growth and Health Study protool,9 and a 3-seond measurement of HR was reorded between the first and seond readings. The mean of the seond and third readings was used in analyses ofbp values. All omparisons of diastoli BP in the 2 ohorts were made with the onset of the fifth Korotkoff phase. In both studies, blood for omplete lipid profiles was drawn into Vautainer tubes (Beton Dikinson, In, Mountain View, Calif) ontaining ethylenediaminetetraaeti aid, and lipid profile measurements were made in the same laboratory, whih followed the standards of the Centers for Disease Control and Preven- November 1999, Vol. 89, No. I I tion (CD and NHLBI." In eah study, students were told in the reruitment letter to abstain from all food and drink, exept water, for 12 hours before blood sampling, and this message was repeated 1 day before the sampling. Compliane with the fasting requirement was asertained by interview. In the LRC study ( ), a 24-hour diet reall was used to evaluate nutrient intakes.2 In the urrent study, a 3-day diet reord was used beause it gives a measure of interdiurnal variability.?3 StatistialAnalyses Database management and statistial analyses were done with SAS software.'4 The distributions of variables investigated in our study were examined for normality, and variane-stabilizing transformations were applied when appropriate. Mean values and standard errors (SEs) for age are presented for the group and the group. Mean values for all other variables reflet adjustment for differenes in age between the 2 groups. Means are presented for the entire group and by sex-rae groups in eah study. Adjusted means and signifiane levels were alulated with the LSMEANS option in the GLM proedure. Standard utpoints used in linial pratie were employed to determine normal and high levels of anthropometri, lipid, and BP variables: For BP, the sex-age-height-speifi 95th perentiles were determined for eah hild from nomograms ompiled by Rosner et al.'5 For BMI, the rae-sex-age-speifi 85th perentiles were seleted from tables of ombined National Health and Nutrition Eduation Survey (NHANES) I and NHANES II data ompiled by Frisanho.'6 For total holesterol the utpoint was set at 2 mg/dl, as reommended by the National Cholesterol Eduation Program pediatri guidelines.'7 The proportions of subjets in eah group whose values fell above these utpoints were then ompared in the 2 ohorts via X2 analysis. To investigate whether hanges from the ohort to the ohort ourred aross the entire distribution or whether the hanges appeared in only a partiular part of the distribution of subjets, we plotted umulative perentages for risk fators for the 2 ohorts, to allow visual observation ofoverlaps and differenes. Results Age and Body Mass The mean age of the students in the original Prineton LRC study was.4 years greater (1.2 ±.6 vs 9.8 ±.3 years, P<.1) than Changes in Childhood CVD Risk Fators that of students in the study. The range of ages was similar for the 2 ohorts ( years in and years in ). The sex ratios of the study samples in and were similar (5% and 49% male, respetively) and the rae ratios were similar (72% and 69% White, respetively). Aross all partiipants, students in the study were taller (P <.1), were heavier (P <.1), and had greater BMI values (P <.1) than those in the LRC study; this was true whether raw data or data adjusted for age were used. Table 1 presents the age-adjusted means and SEs for all study variables. Differenes in weight and BMI for eah sex-rae group in the 2 studies were also signifiant, exept for Blak males, for whom the differene in BMI was marginally signifiant (Table 1). Cumulative frequeny distributions ofbmi for the total ohorts and separate sex-rae groups in the and studies revealed that differenes in BMI between the ohorts were minimal at the lower end ofthe BMI distributions, began at approximately the 4th perentile, and inreased with inreasing BMI, demonstrating that equivalent perentiles were indiative of a higher BMI in the ohort than in the ohort (Figure 1). These distributions also showed that the shift in BMI had an impat on all but the lower end of the distributions, but that the biggest shift in BMI ourred above the 75th perentile. In the ohort, the perentage of hildren with a BMI above the 85th perentile of the ombined NHANES I and II survey samples was 12.4%, ompared with 25.3% in the ohort (P<.1). The prevalene of obesity in the ohort was signifiantly greater in every sex-rae group exept Blak males than it was in the ohort (inrease for Blak males: 24.3% to 32.6%, P = not signifiant [NS]). Blak females had the greatest inrease in BMI. Plasma Lipids and Lipoproteins Plasma lipid profiles in the and study ohorts are summarized for all students and by sex-rae groups in Table 1. An examination oftotal holesterol levels by sex-rae group revealed that in both studies, Blak males and females had higher total holesterol levels than did White males and females. Sex differenes within eah rae group were, however, minimal and nonsignifiant. Mean total holesterol was higher in the than in the study ohorts for all students taken together (17.5 vs mg/dl, P<.1) (Table 1), but not for eah individual subgroup. Differenes in mean total holesterol were Amerian Journal of Publi Health 179

3 Morrison et al. L ) ) ) o (U la n ow._ ( C.) CU) LU m) I- o E Ci mi o FM E C. U) C1) Y o o J) 1 aj) OD 1 ) ) o 1 ) ) CJ) i) CLo$ CD CM N. 11 '1 q CD o o Cf) o C O,, t ai q 6 Cl) L oo o,, o o o ~o6 44 C\l t Co _f N.. Clf)_ C')oC- N..)N LMO O O 'It.iN C N ) CM ( O o\ CD9 - '1* o o n nt y-c C; C; _i )C() CM Ct oi Ci _ Uf) Cr C O L o CO ul 1 1 o.o_ Ct) r (C. s1-. rc N. 1 C (D CON ) O * 4-4- CY L m t' OON '-N C,, To o- t II o( ( ) l _Cm f) O CM C( ) ( CD o CO) ) Clf - O CM N.-- Ca ON o o ) _ ) Co r CD - VI C' C 1- N N C r_ LC (D O 1 o C It C r r44 CD o ) _q s~ _ II H C ) L _- CM _.- r- 6 o _4L1N_ u) ) oq. C") r. _o o o o C IT OCD - T- _ '-CO CO CD _- CY) _ ) L '-_OC'_ 1 o O)tt o N.-) o CO ) 1 CO tl rorn CM 11 Ch (N o Le) * *4- o C:5 N.'- C") CO'_ Ch _ P-r)r- * * -C- CO OO CO )1O r-co r- Cs -r CM T-: oi 4- Lo 1- CO UI)C\ CDC oi 6C? 4)i! _N( N 1 CO 4- * (D N CM r_ CD C C4 (D O U. oi CM N Ch _ Ṉ ) L 4 O. C,r) 4 O O CO mt r. -C i H O 't CO CM a) CJ. COCOd CD Clf _ O O CCD CO) *), _O C O N r-t CM Cf)'- ~Ct) Ch--4 II o O o 'd-4 O L t CO * *- C4 CMO t ) i - O 1H U') U- C13 11 '-CON. O C (ti-c D - 6Ch U CM _ -o r-oo3c C C O v-_o,. C,) O U- CClO Cr) lt o r- Cl) L C'3 11 M 4N CO C 8Cof;,Ue. o Co) a C 4 CM ( Cf)_ ( () M M w O CD~COr- j IDN N('- 3) MT- -N.O o- C( C C CM ) Ch- N. C') - EE E d * U) ] 2 a E E CD 75 oj n b 6 CO) Cu C,) 11 o CU U) ~ C t5 E Cu. Vo n O.)Q 2 ~ Cl) - a) Q QI C 9-J U). _ - I._ C - mi v Q. v 1 v 4 Q. V Q. Cii v Q. I highly signifiant for White females (P<.1) and marginally signifiant for Blak females (P =.11) but not for White males, despite an inrease of 4.5 mg/dl in mean total holesterol, or for Blak males, who had no inrease in this variable. The umulative frequeny distribution of total holesterol for both the and total ohorts and individual sex-rae groups within the 2 ohorts revealed similar shifts in Blak and White females and White males, although only that in White females ahieved signifiane (Figure 2). The figures also showed that the differenes in total holesterol were small at and below the 25th perentile and inreased as the perentile level inreased, in onordane with the shifts in BMI. For Blak males, total holesterol urves in the study were lower than in the study. The prevalene of elevated total holesterol (>2 mg/dl) inreased from 8.% in the ohort to 14.8% overall (P<.1) in the ohort. Blak females had the largest inrease (6.8% to 21.3%). In the study, as in the study, White students had higher triglyeride levels than did Blak students, and females had higher triglyeride levels than did males (Table 1). Aross all groups, the inrease in triglyeride levels from the to the study was 4.3 mg/dl (P <.5). Differenes in triglyerides between sex-rae groups in the 2 study ohorts were not signifiant, exept for White males (P<.5). In , as in , Blak students had higher HDL-C values than did White students. The overall mean HDL-C level was not signifiantly different in the ohort than in the ohort (55.7 vs 56.1 mg/dl, P = NS), nor were the mean HDL-C levels different for the individual sex-rae groups. Mean low-density lipoprotein holesterol (LDL- levels in the overall ohorts in the 2 studies were not signifiantly different, nor were LDL-C levels in the individual sex-rae groups signifiantly different between the 2 ohorts, exept for White females, for whom the LDL-C level was marginally (P =.6) higher in than in (Table 1). Blood Pressure and Heart Rate Among all students investigated, partiipants in the study had signifiantly higher systoli (11.7 vs 98.8 mm Hg, P<.1) and diastoli (59.6 vs 57.7 mm Hg, P<.1) BP levels than did Prineton students in the study (Table 1). Systoli BP levels were higher in eah sex-rae subgroup in the ohort than in the Amerian Journal of Publi Health November 1999, Vol. 89, No. II

4 Changes in Childhood CVD Risk Fators 1975 ohort, but differenes were signifiant only for Blak males (13.2 vs 98.3 mm Hg, P<.1) and White males (11.5 vs 99.1 mm Hg, P<.1). Mean diastoli BP aross all students or in any subgroup was not signifiantly higher in one study than in the other. Mean HR was 2.7 beats per minute (bpm) higher in the ohort (P=.8). The within-subgroup differenes in mean HR ranged from 2. bpm higher in Blak males to 2.2 and 2.8 bpm higher in White males and females, respetively, and 4.9 bpm higher in Blak females in the study than in the orresponding groups in the study. Only in Blak females was the differene statistially signifiant (P =.7). BMI: 1975 vs All groups ~7 4- ( o White males W Blak males ( J 199 I E White females , Blak femalles : Body Mass Index (kg/mi2) FIGURE 1-Comparison of body mass index (BMI) distributions for 2 ohorts of students in the Prineton Shool Distrit overall and by sex-rae group. Points represent the perentage at or below a given BMI. November 1999, Vol. 89, No. I I Cumulative frequeny distributions of systoli BP showed a modest shift to the right aross the range of perentiles, with students in the study having higher BPs than students in the ohort (Figure 3). The prevalene ofelevated systoli BP did not hange signifiantly from the to the study (4.3% vs 2.8%, P = NS). The prevalene of elevated diastoli BP, however, dereased signifiantly from the earlier to the later study (2.7% vs.6%, P<.1). Although eah sex-rae group showed a deline in the prevalene of elevated diastoli BP, only White males (2.8% to.2%, P<.1) and Blak females (4.4% to.%, P<.5) showed signifiant dereases in the prevalene of inreased diastoli BR Nutrition Students reported onsuming slightly fewer alories in (1933 vs 1992 al/day), but this differene was not signifiant. However, differenes in alorie intake in the 2 study ohorts differed markedly by rae. White males and females reported onsuming signifiantly fewer alories, whereas Blak males and females reported onsuming more. Students overll and in eah sex-rae group in the ohort reported onsuming a lower perentage of alories from fat, a lower perentage of alories from saturated fat, and a higher rtio of polyunsaturated (P) to saturated (S) fat than those in the ohort, exept for the P/S ratio in Blak males. Disussion The results of this study of hanges in body mass and CVD risk fators in thirdand fifth-grade students over a 15-year period indiate inreases in BMI and in some risk fators. The inrease in BMI was seen aross all students olletively and in eah sex-rae group from the study to the study, although the inrease was only marginally signifiant in Blak males. The hange was even more striking when the upper range of BMI was examined. In the study, the proportion of students with a BMI exeeding the 85th perentile, on the basis of values in NHANES I and II, was more than twie as great as that in the study (25.3% vs 12.4%). This finding is onsistent with hanges reported by others.4"8 Although an inrease in BMI from the study to the study was seen in eah sex-rae group, the BMI hanges differed aross sex-rae groups, partly beause of small sample sizes in the subgroups. The inrease was smallest in White males (4.7%) and greatest in Blak females (13.1%), with intermediate inreases in Blak males (8.%) and White females (9.6%). Gidding et al. also found sex-rae group differenes in hanges in weight and body mass over an 8-year period in the Bogalusa study, but they reported that only the hanges in Blak females were signifiant.'9 One potential explanation for the different results in their study and ours is that the Bogalusa analysis overed the period from 1973 to National survey data suggest that the greatest hange in obesity in the United States ourred between NHANES I ( ) and NHANES Im ( ).18.2 Thus, the study of the seond Bogalusa ohort may have begun before the beginning of a national trend toward inreased hildhood obesity. A seond Amerian Journal of Publi Health 1711

5 Morrison et al. Total Cholesterol: 1975 vs All groups White males _ o 1 Blak males White females 6-; i Ba kf m ls... 8-Blfeas " Total Cholesterol (mg/dl) FIGURE 2-Comparison of total holesterol distributions for 2 ohorts of students in the Prineton City Shool Distrit overall and by sex-rae group. Points represent the perentage at or below a given level of total plasma holesterol. possible explanation for the different results in our study and that of Giddings et al. is the differene in geographi area in the 2 studies. Geographi differenes in CVD mortality and risk fator status have been desribed for adults' and may also exist for shool-aged hildren. In the present study, inreases in weight and body mass were greater in the top deiles than in the lower deiles. There was no hange in perentile levels at or below the 25th perentile, but the 75th perentile for BMI inreased from 18.5 in the study to 19.7 in the study; this finding is onsistent with that of Gortmaker et al.,2' who reported an inreased skewness of BMI distribution from 1963 through 1965 to 1976 through 198. These results suggest that the observed inrease in body size is not a general phenomenon but is restrited to a subgroup of the hildhood population at the upper end of the distribution of body mass who have beome even more overweight in reent years. This trend may result in an inreased frequeny of the sequelae of obesity, suh as type II diabetes. We have observed suh an inrease in this diagnosis in adolesents in the greater Cininnati area over the past 1 years.22 The mean total holesterol and triglyeride levels of Prineton shoolhildren were signifiantly higher in than in , a trend that runs ounter to those reported for adults.23 It is unlikely that the hanges in lipid levels observed in our study were due to laboratory differenes, beause all lipid profiles were measured in the same CDC-NHLBI-standarized laboratory. In 2 ohorts enrolled 11 years apart ( ), Gidding et al. found a signifiantly greater inrease in triglyeride levels in the later ohort over 8 years of follow-up'9 but found no ohort differenes in lipid values at baseline. In the present study, the omparisons were made of groups examined in and , and inreases in total holesterol were observed from the former to the latter period for both White (P<.1) and Blak (P =.11) females, in whih groups there were also signifiant inreases in the prevalene of elevated holesterol. It is diffiult to interpret the dietary data of our study in ontext. The derease in total alories in White males and females is not onsistent with observed hanges in BMI, but the greater inreases in BMI in Blak males and females, who did have greater reported alori intakes, are onsistent with suh hanges. Moreover, the dietary findings in our study are onsistent with reported dereases in alorie and fat onsumption and inreases in ponderosity seen in Bogalusa, where there was no hange in the method used for olletion of dietary data. The hanges in the proportion of dietary alories from fat and saturated fat and in P/S fat ratios from the study to the study were also most likely real. A omparison of results from the 24-hour diet reall and 3-day reord in the 2 studies showed similar results for the proportion of alories from fat and P/S ratios despite differenes in absolute quantities of dietary alories (i.e., total alories) and grams of fat in the 2 studies.24 As has been noted, overall fat intake in the United States has dereased from 4% of total alories in the 195s and 196s to about 33% in reent years.25 Further, the amount of polyunsaturated fat intake has risen in omparison with that of saturated fat. The derease in fat intake has resulted, however, in a dramati inrease in arbohydrate onsumption, espeially that of simple sugar. It has been suggested that these shifts are responsible for the inreased body weight observed both nationally in the United States26 and in the present study. Even though BMI does not profoundly inrease total holesterol onentrations, the 2 are positively assoiated. Moreover, these data are onsistent with the arguments of Connor and Connor and of Katan et al. in the reent linial debate regarding the benefits of a low-fat, high-arbohydrate diet.25'26 Both sides agree that the fat ontent 1712 Amerian Journal of Publi Health November 1999, Vol. 89, No. I I

6 Changes in Childhood CVD Risk Fators of Amerians' diets is being redued but is being replaed by simple sugars. The inrease in BMI among shool-aged subjets in Prineton from to , in the fae of observed hanges in total alories and fat (dereased in White students and inreased in Blak students), suggests that total energy expenditure dereased from the earlier to the later period. Energy expenditure was unfortunately not measured in either period. However, data from other soures indiate that aftershool ativity has diminished in the United States in reent years. Dietz and Gortmaker reported an inrease in television wathing that appears to be related to inreased obesity.27 Anderssen et al. reported a seular White males Systoli BP: 1975 vs All groups ~ (D41 81Whitek females 8- Blak fmalesf = FIGURE 3-Comparison of systoli blood pressure (BP) distributions for 2 ohorts of students in the Prineton Shool Distrit overall and by sex-rae group. Points represent the perentage at or below a given level of systoli BR November 1999, Vol. 89, No. 1 1 trend of dereasing physial ativity in young adults.28 It has been suggested that resting HR is a risk fator for CVD and may be a measure of physial fitness. Resting HRs were marginally higher in all sex-rae groups in the than in the Prineton ohorts and were markedly higher in Blak females, the group that also had the greatest hange in BMI. This result may indiate that hanges in physial ativity and fitness played an important role in the hanges observed in BMI, HR, and lipids from the first to the seond study. The systoli BP inreased to 11.7 mm Hg in the study ohort from 98.8 mm Hg in the ohort; the observed hanges were slightly greater in Blaks (3.6 mm Hg) than in Whites (2.8 mm Hg) (data not shown). Changes in mean diastoli BP were statistially signifiant aross all students, but not in the sex-rae groups. There was a signifiant deline in the prevalene of elevated diastoli blood pressure in White males and Blak females. It is well known that BP is diretly assoiated with body size. Therefore, the inreased systoli BP observed in students from to is onsistent with the observed inreases in weight and BMI during this same period. These findings in hildren appear to differ from the data for adults in NHANES III, whih suggest that the distributions of systoli and diastoli BP shifted downward during the 3-year period from 196 to The trend toward a dereasing prevalene of elevated diastoli blood pressure observed in the present study may, however, be more onsistent with BP trends seen in adults. The hanges in CVD risk fators assoiated with hanges in obesity observed in our study were not uniform for all groups. The inreased prevalene of hyperholesterolemia in White and Blak females, and the absene of a signifiant inrease in this risk fator in White and Blak males, are not fully onsistent with the observed inreases in BMI, whih were marginally signifiant in Blak males and signifiant in the other study subgroups. Of interest is that Blak males exhibited a marginally inreased BMI without a onomitant inrease in total holesterol. On the other hand, Blak males did exhibit a signifiant inrease in systoli BP, whereas other sex-rae groups did not. Blak males have been shown to have higher peripheral vasular resistane than other sex-rae groups.33' Thus, it is possible that the inrease in ardia output that has been shown to our with obesity may have a greater impat on BP in Blak males than in other sex-rae groups. This finding suggests that the effet of inreasing obesity may not be uniform in the 4 sex-rae groups examined in our study. The findings of this study suggest a disturbing seular trend toward inreased obesity and worsened CVD risk status in hildren in the United States. These temporal hanges may have important impliations for understanding potential sex-rae differenes in the pathophysiology of the sequelae of obesity. Furthermore, the trends toward inreased obesity and worsened CVD risk status among hildren in the United States suggest the development of a publi health problem, whih ould lead to a reversal ofthe reent deline in ardiovasular morbidity and mortality as these hildren beome adults. Amerian Journal of Publi Health 1713

7 Morrison et al. Contributors J. A. Morrison was the prinipal investigator for the study and oversaw the study design, data olletion and analyses, and writing of the paper. F. W James and D. L. Spreher joined J. A. Morrison in negotiating the projet with the shool. D. L. Spreher also performed the lipid profiles and ontributed to the interpretation of the lipid results; F. W James also provided physiian overage at the linis, helped with the blood pressure training, and ontributed to the disussion of indiators of fitness. P. R. Khoury partiipated in the data analyses. S. R. Daniels partiipated in the writing of the paper and interpretation of the blood pressure results. Aknowledgment This work was supported in part by grant SW-9-26 from the Amerian Heart Assoiation Ohio Affiliate. Referenes 1. Feinleib M. Trends in heart disease. Am J Med Si. 1995;31(suppl l):s8-s Sytkowski PA, D'Agostino RB, Belanger A, Kannel WB. 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