Patterns of Cholesterol Distribution in the Participants of a Screening Project

Transcription

1 Patterns f Chlesterl Distributin in the Participants f a Screening Prject Abdul Hamid Shaikh, S With guidelines similar t thse recmmended by the Natinal Chlesterl Educatin Prgram (NCEP), 3,3 individuals were tested fr bld chlesterl in a chlesterl screening and educatin prject. The median age f the participants was 54 years. The mean bld chlesterl level fr all races was 26 mg/dl (S.58 mmll L) (men, 2 mg/dl [5.46 mml/l], and wmen, 2 mg/dl [5.69 mmll L\). In bth sexes an increase in bld chlesterl levels was shwn with age. en reached peak chlesterl levels between and 49 years ld and wmen reached peak chlesterl levels between 50 and 59 years ld. Classificatin f participants int desirable, brderline high, and high bld chlesterl based n the NCEP guidelines shwed % f all participants had desirable, 32% had brderline high, and 24% had high bld chles- rm the Department f edical Technlgy, edical Cllege f Gergia, Augusta, Ga. Reprint requests t the Department f edical Technlgy, edical Cllege f Gergia, Augusta, GA 92 (r Shaikh). 258 terl levels. The study als revealed that belw age years, 66% f all the participants had desirable, 26% had brderline, and nly 9% had high (>2 mg/dl [>6.2 mml/l]) chlesterl levels, whereas in thse lder than years, nly % had desirable, % had brderline high, and 35% had high bld chlesterl levels. The bld chlesterl distributin patterns presented in this article cnfirm earlier studies finding that ageand sex-related differences exist in bld chlesterl levels. pidemilgical studies have demnstrated a strng crrelatin bel tween elevated levels f bld chlesterl and increased rate f crnary artery disease (CAD). The risk f CAD increases steadily as chlesterl levels rise abve 0 mg/dl (5.7 mml/l). The magnitude f the increased rate fr CAD is furfld higher fr peple in the tp 0%.2 Accrding t the Natinal Institutes f Health (NIH) cnsensus cnference3 n lwering bld chlesterl, there is n ppulatin in the wrld that has been re- Labratry edicine Vl. 22, N. 4 April 99 n April 8 prted t have a high rate f CAD with lw bld chlesterl levels. r the first time, the results f the crnary preventin trials f the lipid research clinics4 have prvided direct evidence that lwering bld chlesterl reduces the incidence f CAD. Accrding t the results f the study, a % reductin in ttal chlesterl reduces the risk f CAD by 2%. The recent decline in the United States mean chlesterl level may in part be respnsible fr the decline in CAD mrtality and mrbidity in the United States. Althugh these declining natinal trends are gd news, CAD still remains the number ne killer in the United States. re than millin heart attacks ccur each year; mre than half f them are fatal. Lst wages and prductivity frm CAD cst the United States $6 billin in direct health care csts.4 T reduce the lss f lives and natinal resurces, the Natinal Chlesterl Educatin Prgram (NCEP) has recmmended that health care prfessinals play an imprtant rle in increasing public awareness f chlesterl and ther risk factrs f CAD. It has als advised individuals

2 Table I: Summary f Bld Chlesterl Distributin in the Screening Participants Chlesterl, mg/dl (mml/l) Percentile Grup, y SD ean (4.2) 57(4.06) 5(2.97) 2(2.89) 62(4.8) 63(4.2) 9 (5.) 8 (5.) (4.8) 7 (4.42) (3.) (3.28) 59(4.) 64(4.24) 90(4.9) 26(5.58) (4.88) 88(4.86) 45 (3.74) 45(3.74) 83(4.73) 85(4.78) 224(5,79) 235 (6,07) (5.2) 94(5.0) 52(3.93) 50(3.87) 0(5.7) 92(4.96) 25 (6.49) 2(6.5) (5.87) (5.) 8 (4.68) 64(4.24) 224 (5.79) 6(5.32) 6(7.3) 257 (6.64) (5.8) 2 (6.05) 8 (4.68) 84(4.75) 22 (5.7) 2 (5.94) 9(7.2) 284 (7.) (5.68) 2(6.0) 70(4.39) 86(4.80) (5.6) 2 (6.05) 0 (6.98) 285 (7.) (5.) 239(6.8) 65(4.26) 85(4.78) 6(5.32) 2(6.5) 255 (6.59) 295 (7,62) (5.04) 23 (5.97) 2(3.2) 8 (4.68) 89(4.88) 2 (6.05) 7(7.6) 8(7.8) 90th Percentile Chleste rl (mg/dl) -...«".. " " t' j% edian. 0*4r TJ O Bi... ".» y '..- *' <* th Percentile m" m'"' ig, Bld chlesterl levels fr males. edian and percentile values fr 0-year age grups. t knw their chlesterl levels and eat a healthy "heart" diet, exercise, and quit smking t reduce the risk f CAD. T increase public awareness in the lcal cmmunity, the edical Cllege f Gergia's Wellness Cnsrtium alng with numerus spnsrs and vlunteers cnducted a chlesterl screening prject in Augusta. The chlesterl screening prject designed was similar t ne recently recmmended by the NCEP.5 The prject's design and rganizatinal details have been published in a separate publicatin.6 Our article presents bld chlesterl distributin patterns fund amng the screening participants and classifies the chlesterl levels f participants int desirable, brderline, and high, based n the NCEP bld chlesterl guidelines.7 n April 8 ethds Under the supervisin f clinii cal labratry scientists and ther health care prfessinals, bld chlesterl screening tk place in a shpping mall.6 The detailed methd f the prject has been published.6 After participants were registered and assigned an accessin number, 0 u,l f capillary bld frm the finger puncture was cllected regardless f the dietary status f the individuals. ur Kdak dry chemistry analyzers8 (Ektachem DT ) were used t analyze serum after the bld was centrifuged fr 4 minutes. Vlunteers wrking n these instruments had been trained in a -day wrkshp. The instruments were calibrated and quality cntrl perfrmed using the manufacturer's specificatins. Cmpleted test results were recrded n the registratin card, which was given t the participants. R esults The ttal number f participants tested fr serum chlesterl was 3,3;,4 were men and 2,089 were Labratry edicine Vl. 22, N. 4 April

3 C 0 90th Percentile 'ercentile edian D) E 0 0th 0th Percentile Percentile J -9 r ig 2. Bld chlesterl levels fr females. ediani and percentile values fr 0-year age grups. 0 emales - 0) w > D) sz r- 0 ales "O r I I I ig 3. Bld chlesterl levels fr males and femal es. edian values fr 0-year age grups. wmen. Their ages ranged frm t 92 years ld, with an average f 54 years. The mean chlesterl level was 26 mg/dl (5.58 mml/l) (men, 2 mg/dl [5.46 mml/l], and wmen, 2 mg/dl [5.69 mml/l]). A summary f the bld chlesterl distributin is presented in Table I. igures and 2 represent median, 0th, and 90th percentiles f chlesterl levels in 0-year age grups f men and wmen. igure 3 represents the cmparisn f bld chlesterl distributin patterns in bth sexes. The results shw that bth males and females have similar trends f increases in bld chlesterl with age, with men reaching peak levels between and 49 years ld and wmen reaching peak levels between 50 and years ld. Table II represents the results f classificatin f bth sexes fr 0-year age grups, based n the NCEP bld chlesterl guidelines. Table III summarizes participant classificatin by three age grups: t 89 years, t 39 years, and t 89 years. Classificatin f bld chlesterl levels indicated % f all participants had desirable levels (<0 mg/dl [<5.7 mml/l]), 32% were within brderline high levels (0 t 239 mg/dl [5.7 t 6.8 mml/l]), and 24% had high levels (>2 mg/dl [6.2 mml/l]). The results als shw that in participants yunger than years, 66% had desirable, 26% had brderline, and 9% had high bld chlesterl levels, whereas in participants lder than years, bld chlesterl levels fr bth sexes start shifting twards higher levels. Chlesterl levels in nly % f the participants lder than years were desirable, % were brderline high, and 35% were high. 2 Labratry edicine Vl. 22, N. 4 April 99 n April 8 mment r any public bld chlesterl screening results t be valid, chlesterl measurement shuld be dne under the supervisin f qualified labratry prfessinals, and the training, design, safety, and quality assurance guidelines f the Natinal Chlesterl Educatin Prgram shuld be fllwed. Althugh this study was cnducted befre the publicatin f the NCEP guidelines fr public screening and measuring bld chlesterl, ur screening design and prtcls were similar t NCEP recmmendatins. The precisin and reliability f chlesterl measurement in this study were calculated by duplicate analysis f apprximately % f the participant samples. Accrding t the precisin study results published,6 there was an excellent crrelatin between duplicate test results (r=.97), and there was n significant difference between the mean f duplicate testing as indicated by the paired Student's t test ( =.353 at P=.05). When the mean bld chlesterl levels f the participants (26 mg/dl [5.58 mml/l]) were cmpared with the published9 natinal mean (2 mg/ dl), a slight difference between means was nted (r=2.6 at P=.0), which may have been caused by differences in dietary status, patient preparatin, specimen cllectin techniques, as well as the assay methds used in the tw studies. Accrding t the natinal statistics, mean bld chlesterl levels in the United States have been decreasing amng white men, frm 28 t 2 mg/dl (5.64 mml/l), and amng white wmen, frm 224 t 25 mg/dl (5.56 mml/l). ean bld chlesterl levels have decreased frm 22 t 9 mg/dl (5.7 mml/l) amng black men, with n definite change in black wmen (26 t 24 mg/dl [5.58 t 5.53 mml/l]).9 The bld chlesterl distributin patterns presented in this article cnfirm findings f the early studies'0 that age- and sex-related differences exist in bld chlesterl levels. r example, it has been reprted that men yunger than 50 years have higher bld chlesterl levels than wmen, and wmen lder than 50 years have

4 Table II: Participant Classificatin Int Chlesterl Levels Based n NCEP Guidelines Grup, y N % Desirable, <0 mg/dl (<5.7mml/L) % Brderline, mg/dl ( mml/l) % High Value >2 mg/dl (>6. mml/l) Table III: Participant Classificatin Int Chlesterl Levels fr All Participants and Thse Older and Yunger Than Years fr Bth es Grup, y N % Desirable, <0 mg/dl (<5.7 mml/l) Bth Bth Bth 3,,3,87 3, 8 3,,052, higher bld chlesterl levels than men.0 Similar resu Its have been fund in ur study (ig 3 and Table I). The bld chlesterl distributin patterns presented in this article did nt take int cnsideratin participant dietary and race status. In female participants hrmnal status was als nt taken int cnsideratin It has been reprted that hrmne use in wmen agec 5 t 49 years is assciated with increases in bld chlesterl levels, whereas in wmen aged 50 and lder, hrmne use lwe rs bld chlesterl levels." Classificatin f screening participants int desirable and nndesirable bld chlesterl levels, based n 0 mg/dl (5.7 mml/l) cutff levels, indicates that nly 35% f all the participants yunger than years had bld chlesterl levels abve 0 mg/dl (5.7 mml/l), whereas 72% f all the participants lder than years had bld chlesterl levels abve 0 mg/dl (5.7 mml/l). These results crrelate very well with the findings f the ramingham and ther studies,2-7'2 in which persns lder than years had the highest n April 8 % Brderline, mg/dl ( mml/l) % High Value >2 mg/dl (>6. mml/l) bld chlesterl levels and als the highest rates f mycardial infarctin. The bld chlesterl distributin patterns presente d herein prvide valuable infrmatin abut chlesterl levels. These chlesterl levels culd be used t detect any abnrmal bld chlesterl trend in the cmmunity as well as serve as a base level fr any future chlester screening in the cmmunity Acknwledgment Drs Warren Karp, Jula Crwley, and Harry Davis prvided valua >le review and suggestins n this manuscript. Labratry edicine Vl. 22, N. 4 April 99 26

5 References. Castelli WP, Garrisn RJ, Wilsn W, et al: Incidence f crnary heart disease and lipprtein chlesterl levels: The ramingham Study. JAA 986;256: artin J, Hulley SB, Brwner WS, et al: Serum chlesterl, bld pressure and mrtality: Implicatins frm a chrt f,662 men. Lancet 986;2: NIH Cnsensus Develpment Cnference: Lwering bld chlesterl t prevent heart disease. JAA 985;253: Lipid Research Clinics Prgram: The Lipid Research Clinics crnary primary preventin trial results: Reductin in incidence f crnary heart disease. JAA 984;25: Recmmendatins: Regarding Public Screening fr easuring Bld Chlesterl. Summary f a Natinal Heart, Lung and Bld Institute Wrkshp. US Dept f Health and Human Services. NIH Publicatin N , Shaikh AH: A mdel chlesterl screening and educatin prject. Clin Lab Sci 989;2: Natinal Chlesterl Educatin Prgram. Reprt f the Expert Panel n Detectin, Evaluatin and Treatment f High Bld Chlesterl in Adults. US Dept f Health and Human Services. NIH Publicatin N , Burke JJ, ischer P: A clinician's guide t the ffice measurement f chlesterl. JAA 988;259: Natinal Center f Health Statistics; Natinal Heart, Lung and Bld Institute Cllabrative Lipid Grup: Trends in serum chlesterl levels amng United States adults age -74 years: Data frm the Natinal Health and Nutritin Examinatin Survey 9 t 980. JAA 987; 257: The Lipid Research Clinics Prgram Epidemilgy Cmmittee: Plasma Lipid Distributin in Selected Nrth American Ppulatin: The Lipid Research Clinics Prgram Prevalence Study. Circulatin 979;:4-9.. Wallace RB, Hver J, Sandler D, et al: Altered plasma-lipid assciated with ral cntraceptives r estrgen cnsumptin. Lancet 977; 2: Lerner DJ, Kannel WB: Patterns f crnary heart disease mrbidity and mrtality in the sexes: A 26 year fllw up f the ramingham ppulatin. Am Heart J 986;: Labratry edicine Vl. 22, N. 4 April 99 n April 8