The Dynamics of Health Disparities; U.S. Mortality Disparities by Education, Richard Miech, Fred Pampel, Jinyoung Kim, and Rick Rogers

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1 Th Dynamics of Halth Disparitis; U.S. Mortality Disparitis by Education, Richard Mich, Frd Pampl, Jinyoung Kim, and Rick Rogrs Inquality is a major caus of dath in th Unitd Stats. Around 13, fwr daths would hav occurrd in 25 among adults agd if th dath rat for popl with 12 or fwr yars of ducation had bn th sam as it was for popl with 13 or mor yars mor ducation (Kung, Hoyrt, Xu, and Murphy 28; National Cntr for Halth Statistics 29). This lvl of magnitud is about th sam as th third lading caus of dath in th U.S. (National Cntr for Halth Statistics 29). Inquality s lvl of impact on mortality has changd ovr tim and most likly continus to chang today. Howvr, almost all information on th trnds in ducation and mortality is dscriptiv and coms from rports in public halth or mdical journals (includd in th rviw blow). A sociological prspctiv holds th potntial to contribut uniqu and important insights into ths changs, but has yt to b xtnsivly applid to this topic (for an important xcption s Phlan, Link, Diz-Roux, Kawachi, and Lvan 24). This lack of attntion is surprising in light of th cntrality of inquality to th fild of sociology and th importanc of mortality disparitis as a social problm (cit xx; NIH xx). In this study w tak a uniqu approach and us th concpt of a balanc-scal for th analysis of trnds in mortality disparitis by ducation from 1989 to 25. By balanc-scal w rfr to a scal that maks us of a balanc bam to dtrmin which of two wights is havir.g. th typ of scal hld out by th blindfoldd Lady Justic. W focus on th approximatly 1 major causs of dath and xamin th xtnt to which causs of dath with incrass in disparitis hav outwighd thos with dcrass, or vic-vrsa. This approach is a dpartur from customary studis in this fild, which typically prsnt dtaild information for only a handful of spcific causs of dath, if any at all. W highlight th fact that forcs to incras and dcras mortality disparitis ar working simultanously and ar in comptition with on anothr, and th rsults from this study will indicat both thir rlativ influnc and also which of th two currntly prvails. Th analysis cntrs on thr spcific prdictions. Th first is that disparitis ar simultanously incrasing and dcrasing across diffrnt causs of dath during th study priod. Th scond is that th ovrall disparity is constant or incrasing. W dvlop this hypothsis on th basis of th fundamntal caus prspctiv, which lads us to xpct that mortality disparitis in th causs of dath that ar gaining influnc offst any dclining disparitis in othr causs of dath. Th third, altrnativ hypothsis is that th ovrall mortality disparity by ducation has bn dcrasing in rcnt yars. W dvlop this hypothsis on th basis of diffusion of innovation thory, which lads to th xpctation that th sum influnc of dcrasing disparitis outwighs that of

2 incrasing disparitis as mdical innovations that improv halth gradually diffus across all socioconomic lvls and as w rach th uppr limits of human lif xpctancy. Th Trnds Mortality disparitis by ducation hav bn stadily incrasing sinc at last th 196s, a finding robust across studis that us diffrnt data sts and diffrnt analytical mthods. Whil lif xpctancy has incrasd for all dmographic groups in rcnt dcads, its fastr incras among high ducation and incom groups has ld to a widning disparity, particularly among mn. Evidnc for incrasing mortality disparitis btwn th 196s and th 198s coms from multipl sourcs. From 196 to 1971 an incras in mortality disparitis for mn is notd by Fldman t al. (1989), who usd th National Halth and Nutrition Examination Survy (NHANES 1) and th Matchd Rcord Study. Concurring vidnc for an incras in mortality disparitis by socioconomic status from 196 to 1986 coms from Pappas t al. (1993), who xamind trnds in mortality disparitis using th National Mortality Followback Survy and th National Halth Intrviw Survy. Furthr vidnc for an incrasing mortality by ducation across th 196s and 198s for mn (but not womn) coms from Prston and Elo (1995), who usd th National Longitudinal Mortality Survy. Incrass in mortality disparitis by ducation hav continud through th 199s into at last th yar 21. Using dath crtificat information from 43 stats and Washington D.C., Ahmdin t al. (28) rport that from 1993 to 21 th all-caus mortality rat ratio of th last v. most ducatd incrasd from 2.9 to 4.4 among whit mn, from 2.1 to 3.4 for black mn, and from 2.6 to 3.8 for whit womn. Studis of halthy lif xpctancy (Crimmins and Saito 21) and cohort pattrns of survival (Laudrdal 21) confirm arlir studis by dmonstrating widning disparitis through 199 but do not xtnd thir analysis to th last dcads. Singh (24) and Singh and Siahpush (22; 26) find widning disparitis at th county lvl through 2 but do not study individual diffrncs in mortality by ducation. Stnland Hu, and Walkr (24) xamin occupational disparitis in all-caus mortality for mployd prsons in 27 stats btwn 1984 and Thy find that mortality diffrncs wr sustaind through th 199s and incrasd for mn, but th rsults ar limitd in gographic covrag, focus only on workrs, and do not compar trnds by caus. Stnland, Hnly, and Thun (22) compar a fw caus-spcific dath rats by ducation for two cohorts ovr th priod from Thy find incrasing disparitis for hart disas, diabts, and, for womn only, lung cancr, but th sampl, basd on Amrican Cancr Socity voluntrs, is not rprsntativ th population. A pattrn of widning mortality disparitis by ducation in rcnt dcads is not uniqu to th Unitd Stats it also documntd in Austria, Finland, Norway, Dnmark, and Nw Zaland (Schwarz 27). Thory and Prdictions

3 Whthr ths incrass in mortality disparitis by ducation hav continud in rcnt yars is not known, and this study updats ths trnds from 1989 to 25. This analysis diffrs from customary studis in this fild bcaus w focus on th distribution of disparity trnds across approximatly 1 major causs of dath, a focus guidd by sociological thory, as dscribd blow, that lads us to mpirically tst thr prdictions. Htrognity in Disparity Trnds W first tst th prdiction that substantial htrognity is prsnt in disparity trnds across causs of dath, with som disparitis incrasing, som dcrasing, and som unchanging during th sam study priod. On rason to xpct htrognity is that many bhaviors and tratmnt hav consquncs that ar disas-spcific and thrfor diffrnt disass ar subjct to diffrnt forcs that may impact mortality disparitis by ducation ovr tim. Anothr rason to xpct htrognity is that diffrnt disass hav diffrnt lag tims btwn onst and dath, so that a common influnc -- such as a national dcras in smoking rats -- may hav a mor immdiat ffct for on disas, such as hart disas, as compard to anothr, such as lung cancr. Prsistnt or Growing Disparitis A scond prdiction w tst is that mortality disparitis by ducation hav continud at prvious lvls or incrasd bcaus th sum influnc of disparitis that hav incrasd ovr th study priod offst or vn outwigh th sum influnc of disparitis that dcrasd. This prdiction is supportd by th fundamntal caus prspctiv, which posits that halth disparitis ar ultimatly linkd to th unqual distribution across social strata of rsourcs such as mony, powr, and bnficial social connctions (Link and Phlan 1995). Importantly, ths rsourcs ar flxibl, which mans that thy continu to advantag th halth of popl in th uppr social strata vn as th halth profil of a population changs ovr historical tim. As long as ths flxibl rsourcs ar distributd unqually within socity, popl in th uppr social strata will us thm to thir halth advantag and substantial halth disparitis in mortality ar xpctd to prsist or grow in th U.S. Bcaus almost all masurs of inquality in th U.S. indicat constant or incrasing inquality in rcnt dcads (xx), mortality disparitis ar xpctd to hav rmaind constant or incrasd in rcnt yars. A ky lmnt of th fundamntal caus prspctiv is its prdiction that halth disparitis will prsist in th futur, vn though no on knows th disass and conditions that will b in forc at that tim. As background, Link and Phlan (1995) point out that 1 yars ago th top killrs in th U.S. wr tubrculosis, diarrha, and pnumonia, and ths disass disproportionatly affctd popl in th lowr social strata. A prson living 1 yars ago might rasonably hav thought that a substantial rduction in th influnc of ths top killrs would also lad to substantial rduction in mortality disparitis by socioconomic strata. As it turns out, in th subsqunt 1 yars th influnc of ths top killrs did indd substantially diminish, but mortality disparitis did not. Th old killrs wr rplacd by nw ons spcifically, cardiovascular disas, cancr, and strok (Hron, Hoyrt, Murphy, Xu, Kochank, and Tjada-Vra 29; Omran 25) (xx) which ach disproportionatly affct popl in th lowr socioconomic strata (cit xx). This prspctiv prdicts that whn th U.S.

4 succssfully countrs th top killrs of today thn whatvr nw ons rplac thm will hav substantial mortality disparitis bcaus popl in th uppr social strata will hav mor rsourcs to avoid thm, whatvr thy may b. This insight of th fundamntal caus prspctiv allows us to furthr spcify this scond prdiction. Not only should incrasing disparitis outwigh dcrasing disparitis, but ths incrasing disparitis should b particularly acut among causs of dath that ar bcoming mor prominnt ovr tim. If disparitis wr not prsnt in th nw, prominnt causs of dath that rplac old ons, thn disparitis by socioconomic strata would hav disappard many dcads ago. Equalization A third prdiction, which is in contrast to th fundamntal caus prdiction, is that ovrall mortality disparitis by ducation hav dcrasd in rcnt yars bcaus th sum influnc of dcrasing mortality disparitis outwighs th influnc of any disparitis that ar incrasing or constant. This prdiction is basd on th diffusion of innovation prspctiv, which posits a catch-up procss in which mor advantagd groups first gain th bnfits of progrss in knowldg and tratmnt but lss advantagd groups vntually follow in changing halth bhavior and rciving th latst tratmnts. This pric-of-progrss argumnt ss incrass in disparitis as th short-trm rsult of advancs, but on that is slf-corrcting in th long run. From this prspctiv th incrass in mortality disparitis in rcnt dcads st th stag for dcrass in th futur. Th mchanism undrlying this argumnt focuss on th adoption and diffusion of innovations. In th classic modl dscribd by Rogrs (23), highly ducatd popl adopt innovations most quickly, whil lss ducatd prsons follow in adoption aftr a lag priod. In th ara of halth, th ducatd hav rsourcs that hlp thm idntify nw ways to improv thir halth, chang thir bhavior in accordanc with rcnt rsarch and rcommndations, and gain accss to th most up-to-dat halth car. With fwr rsourcs, th lss ducatd dpnd on widsprad publicity about halth bhaviors, th guidanc of halth profssionals, and imitation of mor ducatd groups. Th diffusion of halth innovations movs slowly but vntually rachs disadvantagd groups and thrby hlps modrat disparitis. Rising disparitis svral dcads ago likly rsultd from changs in pattrns of smoking and nw tratmnts for hart disas that hav had a major impact on longvity. With lowr ducation groups also coming in mor rcnt yars to njoy halth advantags from lowr smoking and tratmnt for hart disas, disparitis should dclin. A trnd toward qualization fostrd by diffusion of knowldg and mdical innovations may hav spcial forc th last fw dcads for anothr rason. As high ducation groups rach longr lif xpctancis, an outcom brought about by progrss in th 197s and 198s, furthr progrss coms mor slowly. Advancs in public halth and mdical tchnology during a priod of dlayd dgnrativ disass (Olshansky and Ault 1986) xtnd th ags at which dgnrativ disass tnd to kill mortality and bring som groups closr to a possibl ciling in longvity. Bcaus th high liklihood of

5 dath ovrwhlms othr influncs at oldr ags, th impact of socioconomic charactristics tnds to dclin (Hous, Lpkowski, Kinny, Mro, Ksslr, and Hrzog 1994). Continud progrss in lowring mortality, xtnding lif, and concntrating dath at oldr ags should particularly affct high ducation groups that hav alrady njoyd th most progrss. As thir progrss slows, lowr ducation groups with mor room to grow mov closr to th mortality of high ducation groups. METHODS Th analysis is basd on two main data sts to calculat dath rats for adults ag 4-64 by causs of dath. Th first is th U.S. Vital Statistics, which consists of yarly data from all dath crtificats issud in th Unitd Stats. Th data contain information on th rac, ag, and sx of dcdnts. Th data also contain information on th contributing causs of dath. In 1989 th first yar in which th ducational attainmnt of th dcdnt was includd on th dath crtificats th U.S. Vital statistics includd about 2.1 million rcords and by 25 th numbr of daths incrasd to about 2.5 million. Th analysis calculatd th numbr of daths for ach caus of dath as catgorizd in th ICD-113 cods (cit xx). For vry yar in th study th analysis countd how many tims ach caus of dath appard in th dath crtificats, ithr as an undrlying caus of dath or as a contributing caus of dath. Consquntly, dath crtificats with multipl, contributing causs of dath wr countd mor than onc in th analyss that tak into considration causs of dath. Th scond main sourc of data is th U.S. Cnsus. To calculat mortality rats th Cnsus data providd information for th dnominator. For th purposs of this analysis it was ncssary to driv from th Cnsus stimats of th total population of th Unitd Stats. Consquntly, w supplmntd information on th siz of th civilian population for which th Cnsus provids yarly information with information on th population that living in group quartrs. For this lattr information w imputd data from th dcnnial 199 and 2 cnsuss. All analyss ar ag-standardizd by fiv-yar ag groups to th yar 2 population. RESULTS Figur 1 shows th trnd in ovrall mortality disparity by ducation from 1989 to 25 for mals and fmals, rgardlss of caus of dath. Consistnt with past trnds, th mortality disparity incrasd ovr this tim priod. This incras is vidnt in Figur 1 by a widning distanc ovr tim btwn th mortality rats of popl with th lowst and highst ducation lvls. This widning is prsnt in both analyss of mn and womn. In analyss not shown w considrd whthr th widning was th rsult of a spcific ag group. W ran analyss paralll to thos that w ran for Figur 1, but for

6 ach sparat fiv yar ag group from 4 to 65, sparatly for mn and womn. A widning disparity in mortality rats by ducational attainmnt was prsnt for vry singl fiv-yar ag group, suggsting that th trnd is a historical priod ffct and cannot radily b xplaind as a cohort ffct. Figur 2 disaggrgats th trnds in Figur 1 by rac and thnicity. A widning mortality disparity by ducation is prsnt for all dmographic groups. Th incras in th disparity is smallst for Hispanic mn and womn. To xamin ths trnds in mor dtail w focusd on th approximatly 1 main causs of dath as codd in th U.S. Vital statistics. W focusd on th priod from 1999 to 25, which is whn all daths wr codd to th sam nosology of th ICD-1. In 1998 and bforhand daths wr codd to th substantially diffrnt systm of th ICD-9. Figurs 1 and 2 indicat that th trnd in widning disparity continud throughout 1999 and 25 and thrfor th tim priod is stratgic for invstigation of th widning of socioconomic disparitis in mortality. Figur 3 is a histogram of changs in mortality disparitis for mn and womn by causs of dath. Disparity chang is dfind as th siz of th morality disparity in 25 minus th siz of th mortality disparity in If th disparity incrasd thn th valu of th disparity chang was positiv, and if it dcrasd thn it was ngativ. Figur 3 shows that for mn th numbr of causs of dath with incrasing mortality disparitis by ducation from 1998 to 25 was about qual to th numbr of thos with dcrasing ons. Spcifically, 48 of 12 causs of dath has incrasing disparitis and 54 had dcrasing disparitis. Figur 3 shows that for womn th numbr of causs of dath with incrasing mortality disparitis by ducation was substantially gratr than thos with dcrasing ons. Spcifically, incrasing disparitis outnumbrd dcrasing disparitis by a factor of mor than two to on, with 74 incrasing and 32 dcrasing. DISCUSSION This study st out to updat trnds in mortality disparitis by ducation using th U.S. Vital Statistics and th U.S. Cnsus. Th analysis is uniqu bcaus to our knowldg it is on of th first to considr in dtail th rlativ influnc of incrasing and dcrasing mortality disparitis across major causs of dath. Consistnt with findings from prvious ras, w find that th mortality disparity by ducation has incrasd in rcnt dcads, for both mn and womn. Our analysis highlights that th incrasing mortality disparity is not uniform across causs of dath, and that substantial variability is prsnt, particularly among mn. For mals th numbr of causs of dath with incrasing mortality disparitis was about qual to th numbr with dcrasing mortality disparitis. This is an ncouraging finding for thos who sk to rduc mortality disparitis, bcaus it suggsts that such rduction can and is possibl. If th forcs that ar rducing mortality disparitis can b xtndd

7 to additional causs of dath thn it is possibl that ovrall mortality disparitis can start to b rvrsd a rvrsal that has bn dsird by not xprincd for at last fifty yars. For womn th numbr of causs of dath with incrasing mortality disparitis outnumbrd thos with dcrasing disparitis by mor than two to on. Ths rsults thrfor suggst that whatvr forcs ar incrasing mortality disparitis hav had a gratr influnc on womn than mn. Of particular intrst and an issu that will b considrd in latr vrsions of this papr ar causs of dath that had incrasing disparitis for mn by dcrasing disparitis for womn. This study has considrably furthr to go bfor it is finishd, but hopfully th rsults thus far ar sufficint to giv th PAA rviwrs an ida of whr w ar hadd and what w hop to accomplish.

8 Rfrncs Ahmdin, Jmal, Elizabth Ward, Robrt N. Andrson, Taylor Murray, and Michal J. Thun. 28. "Widning of Socioconomic Inqualitis in U.S. Dath Rats, " PloS ONE 3:2181. Crimmins, E.M. and Y. Saito. 21. "Trnds in Halth Lif Expctancy in th Unitd Stats, : Gndr, Racial, and Educational Diffrncs." Journal of Social Scinc and Mdicin 52: Fldman, Jacob J., Dian M. Makuc, Jol C. Klinman, and Joan Cornoni-Huntly "National Trnds in Educational Diffrntials in Mortality." Amrican Journal of Epidmiology 129: Hron, Mloni, Donna Hoyrt, Shrry Murphy, Jiaquan Xu, Knnth D. Kochank, and Btzaida Tjada-Vra. 29. "Daths: Final Data for 26." National Vital Statistics Rports 57:1-12. Hous, Jams S, J M Lpkowski, A M Kinny, R P Mro, R C Ksslr, and A R Hrzog "Th Social Stratification of Ag and Halth." Journal of Halth and Social Bhavior 35: Kung, Hsiang-Ching, Donna L. Hoyrt, Jiaquan Xu, and Shrry L. Murphy. 28. "Daths: Final Data for 25." National Vital Statistics Rports 56: Laudrdal, D. S. 21. "Education and Survival: Birth Cohort, Priod, and Ag Effcts." Dmography 38: Link, Bruc G. and Jo Phlan "Social Conditions as Fundamntal Causs of Disas." Journal of Halth and Social Bhavior (Extra Issu):8-94. National Cntr for Halth Statistics. 29. Halth, Unitd Stats, 28 With Chartbook. Hyattsvill, MD. Olshansky, S. Jay and B. Ault "Th Fourth Stag of th Epidmiologic Transition: Th Ag of Dlayd Dgnrativ Disass." Th Milbank Quartrly 64: Omran, Abdl R. 25. "Th Epidmiological Transition: A Thory of th Epidmiology of Population Chang." Milbank Mmorial Fund Quartrly 83: Pappas, Grgory, Susan Qun, Wilbur Haddn, and Gail Fishr "Th Incrasing Disparity in Mortality btwn Socioconomic Groups in th Unitd Stats, 196 and 1986." Th Nw England Journal of Mdicin 329:13-9. Phlan, Jo C., Bruc G. Link, Ana V. Diz-Roux, Ichiro Kawachi, and Bruc Lvan. 24. ""Fundamntal Causs" of Social Inqualitis in Mortality: A Tst of th Thory." Journal of Halth and Social Bhavior 45: Prston, Samul H. and Irma T. Elo "Ar Educational Diffrntials in Adult Mortality Incrasing in th Unitd Stats?" Journal of Aging and Halth 7: Rogrs, Evrtt M. 23. Diffusion of Innovations. Nw York: Th Fr Prss. Schwarz, Franz. 27. "Widning Educational Disparitis in All-Caus Mortality: An Analysis of Austrian Data with Intrnational Comparisons." Vinna Yarbook of Population Rsarch: Singh, Gopal K. 24. "Ara Dprivation and Widning Inqualitis in U.S. Mortality, " Amrican Journal of Public Halth 93:

9 Singh, Gopal K. and Mohammad Siahpush. 22. "Incrasing Inqualitis in All-Caus and Cardiovascular Mortality among U.S. Adults Agd Yars by Ara Socioconomic Status." Intrnational Journal of Epidmiology 31:6-13. Singh, Gopal K. and Mohammad Siahpush. 26. "Widning Socioconomic Inqualitis in U.S. Lif Expctancy, " Intrnational Journal of Epidmiology 35: Stnland, Kyl, Jan Hnly, and Michal Thun. 22. "All-Caus and Caus-Spcific Dath Rats by Educational Status for Two Million Popl in Two Amrican Cancr Socity Cohorts, " Amrican Journal of Epidmiology 156: Stnland, Kyl, Shrry Hu, and Jams Walkr. 24. "All-Caus and Caus-Spcific Mortality by Socioconomic Status Among Employd Prsons in 27 U.S. Stats, " Amrican Journal of Public Halth 94:

10 Mn 139 D a t h s p r Yar Womn D a t h s p r Yar Figur 1: Trnds in Mortality Lvls by Education for Mn and Womn Ag 4-64 for th Yars Lgnd: Lss than High Som High sch. School Collg Collg+ Ovrall trnd Sourc: U.S. Vital Statistics and U.S. Cnsus Not: Ag standardizd to yar 2 U.S. Population

11 Whit Mn Black Mn D a h s p Whit Womn Black Womn D a h s p Yar Yar Lgnd: Lss than High Som High sch. School Collg Collg+ Ovrall trnd Hispanic Mn Hispanic Womn Yar t r t r

12 45% Mn 4% 35% D n s i t y 3% 25% 2% 15% 1% 5% % Chang in Absolut Disparity From 1989 to 25 6% Womn D n s i t y 5% 4% 3% 2% 1% % Chang in Absolut Disparity From 1989 to 25 Figur 3: Histograms of Chang in Mortality Disparitis from 1999 to 25. Changs Masurd in Daths pr 1,.

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