Original Research Article. Dement Geriatr Cogn Disord 2007;24: DOI: /

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1 Originl Reserch Article Dement Geritr Cogn Disord 2007;24: DOI: / Accepted: June 26, 2007 Published online: August 24, 2007 A Normtive Study of the Revised Hsegw Dementi Scle: Comprison of Demogrphic Influences between the Revised Hsegw Dementi Scle nd the Mini-Mentl Sttus Exmintion J.W. Jeong K.W. Kim, c D.Y. Lee b, c S.B. Lee J.H. Prk E.A. Choi J.Y. Choe Y.J. Do J.S. Ryng H.A. Roh Y.S. Prk Y. Choi d J.I. Woo b, c Deprtment of Neuropsychitry, Seoul Ntionl University Bundng Hospitl, Gyeonggi-do, b Deprtment of Neuropsychitry, Seoul Ntionl University Hospitl, nd c Deprtment of Psychitry nd d Medicl Reserch Collborting Center, Seoul Ntionl University College of Medicine, Seoul, Kore Key Words Revised Hsegw Dementi Scle Mini-Mentl Sttus Exmintion Norm Eduction Gender Age A b s t r c t B c kg r o u n d /A i m s : We investigted the demogrphic influence on the performnce of the Revised Hsegw Dementi Scle (HDS-R) nd provided normtive dt of the HDS-R in the elderly. Methods: The HDS-R ws dministered to 803 community-dwelling cognitively norml elderly subjects ged 55 yers or over. Cognitive disorders nd psychitric disorders were strictly excluded using the CERAD-K ssessment pcket nd the Mini-Interntionl Neuropsychitric Interview. The demogrphic influence on the performnce of the HDS-R ws exmined using multiple liner regression nlyses, nd compred with tht on the performnce of the Mini-Mentl Sttus Exmintion (MMSE) using the Chow test nd t sttistics. Overlpping strt were used in developing ge-, eduction- nd gender-specific normtive dt of the HDS-R. Results: Age, eduction, nd gender influenced significntly the performnce of the HDS-R, nd explined 22.5% of the totl score vrince. Older ge, lower eduction, nd mle gender were ssocited with lower performnce of the HDS-R. However, the demogrphic influence on the HDS-R ws much weker thn tht on the MMSE (t = 5.578, d.f. = 800, p! 0.001). The normtive dt of the HDS-R strtified by ge (60 69, 70 79, 6 80), eduction (0 6, 7 12, 6 13), nd gender were presented. Conclusions: The HDS-R ws more robust to demogrphic influences thn the MMSE, nd normtive dt my contribute to improving further its dignostic ccurcy for dementi. Introduction Copyright 2007 S. Krger AG, Bsel As the prevlence of dementi increses nd interventions for it become vilble, there is n incresing need for ccurte screening tests for the erly detection of dementi. First of ll, the tests for screening dementi should be cpble of being quickly nd esily dministered not only by physicins but lso by nurses or other trined helth personnel. In this sense, brief cognitive tests which tke less thn 15 min re more widely used in primrycre settings nd epidemiologicl studies thn the Alz - heimer s Disese Rting Scle [1] nd the Mttis Dementi Rting Scle [2]. Among these brief cognitive tests, the Mini-Mentl Sttus Exmintion (MMSE) [3] is the most widely used test for screening dementi nd ssessing cognitive chnges in dementi ptients [4]. Fx E-Mil krger@krger.ch S. Krger AG, Bsel /07/ $23.50/0 Accessible online t: Ki Woong Kim, MD, PhD Seoul Ntionl University Bundng Hospitl 300 Gumi-dong, Bundng-gu, Seongnm-si Gyeonggi-do (Kore) Tel , Fx , E-Mil kwkimmd@snu.c.kr

2 However, the MMSE ws originlly developed to evlute elderly psychitric ptients rther thn dementi ptients, nd thus ws criticized for its level of sensitivity nd specificity for dementi nd the insensitivity to frontl dysfunction [5, 6]. Furthermore, it ws significntly influenced by demogrphic fctors [4]. Compred to the MMSE, the Revised Hsegw Dementi Scle (HDS-R) [7], which ws originlly developed for screening dementi, hs severl dvntges. First, it hs the mesures for ssessing frontl function, nd higher reltive weight of memory mesures thn the MMSE. The dded or strengthened mesures exmine the cognitive domins tht re known to be impired erly in the development of dementi [8, 9]. We illustrted in our previous work tht the HDS-R hd the better dignostic ccurcy for Alzheimer s disese thn the MMSE [10]. Second, the HDS-R cn be dministered to disbled elderly who hve motor impirment, since it does not contin ny performnce tests such s visuosptil bility nd prxis tests. Third, the dignostic ccurcy of the HDS-R for dementi ws found to be less influenced by the level of eduction thn tht of the MMSE [10], which suggested tht the HDS-R my be robust to eductionl influences. However, the demogrphic influences on the performnce of the HDS-R hve not been directly studied, nd thus its normtive dt re not yet vilble. In ddition, these influences hve not been compred quntittively with those on the performnce of the MMSE. This might hve confined its use to Est Asin countries. Therefore, we investigted nd compred the demogrphic influences on the performnce of the HDS-R nd the MMSE, nd provided normtive dt of the HDS-R strtified by demogrphic fctors in Koren elderly popultion ged 60 yers or over, which my lso provide the bses of our previous observtion tht the HDS-R hd the better dignostic ccurcy for Alzheimer s Disese thn the MMSE. Mterils nd Methods All of the subjects were community-dwelling elderly, ged 55 or over, who enrolled in the Koren Longitudinl Study on Helth nd Aging nd the Seoul Study [11]. Ech subject ws exmined by psychitrist with dvnced trining in neuropsychitry nd dementi reserch ccording to the protocol of the Koren version of the Consortium to Estblish Registry for Alzheimer s Disese (CERAD) clinicl ssessment bttery (CERAD-K) [12] nd the Mini-Interntionl Neuropsychitric Interview (MINI) version 5.0 [13]. The CERAD-K consists of stndrdized clinicl interview on demogrphic informtion, cognitive nd functionl sttus, drug inventory, depression nd medicl history, generl physicl nd neurologicl exmintions nd the Clinicl Dementi Rting (CDR) [14]. The MINI is structured dignostic interview for DSM-IV [15] psychitric disorders. Along with the MINI, the 17-item Hmilton Depression Scle [16], the Koren version of the Geritric Depression Scle [17] nd the Koren version of the Center for Epidemiologic Studies Depression Scle [18] were lso dministered. After the clinicl exmintion, pnel consisting of 4 psychitrists reviewed ll of the vilble rw dt from the clinicl evlutions nd mde the clinicl dignoses. The subjects who were dignosed s hving mjor Axis I psychitric disorders including dementi nd mjor depressive disorder ccording to the DSM-IV criteri [15] were excluded. Those who hd serious medicl nd neurologicl disorders tht could ffect their mentl function were lso excluded. Individuls with minor physicl bnormlities (e.g. dibetes with no serious complictions, essentil hypertension, mild hering loss, etc.) were not excluded. All subjects hd dequte vision nd hering, lthough mny wore glsses nd some required hering id. Trined psychologists nd nurses who were blinded to the psychitrists clinicl evlution dministered the Koren version of the HDS-R [19] nd the MMSE. We mde n instruction mnul nd trined the rters to conform to it in order to stndrdize the dministrtion nd to ensure the uniformity of the dt gthered. A multiple liner regression nlysis with stepwise vrible selection ws performed to ssess the reltive contribution of ge, eduction, nd gender on the scores of the HDS-R nd MMSE. To compre the demogrphic effect on the HDS-R nd MMSE, we compred coefficients of determintion ( R 2 ) of their regression models using the t sttistic developed by Hotelling [20]. To compre the regression coefficients of ge, eduction, nd gender for the HDS-R with those for the MMSE, the Chow test [21] ws performed. A series of 3! 4! 2 ANOVA were lso performed to determine ny min effects nd interctions of ge (55 69, 70 79, nd 80 94), eductionl level (0 6, 7 9, 10 12, nd 6 13 yers) or gender on the performnce of the HDS-R. There were 3 ge groups, corresponding to the ge strtifiction used in our previous normtive studies [22 24]. There were 4 eductionl level groups, corresponding to the ctegoricl distinctions in the Koren public eduction system. Post-hoc contrsts with Scheffé s method were conducted when ny min effect of eduction ws determined to be significnt by ANOVA t the p! 0.05 level. The norms of the HDS-R were strtified by the demogrphic fctors which hd the min effects on the performnce of the HDS-R. To mximize the quntity of informtion nd clinicl usefulness of the dt, overlpping strt were used in developing the normtive dt following the procedures described by Puker [25]. R e s u l t s A totl of 803 norml elderly subjects (363 mle nd 440 femle) were enrolled. Fifty-five percent of the subjects were women, nd the men ge nd eductionl lev- A Normtive Study of HDS-R Dement Geritr Cogn Disord 2007;24:

3 el of the mle group were significntly higher thn those of the femle group (t = 3.83, p! for ge; t = 14.56, p! for eduction). The demogrphic chrcteristics of the subjects re described in tble 1. The ge-, eduction-, nd gender-controlled Person correltion coefficient between the HDS-R nd MMSE ws (p! 0.001). Stepwise multiple regression nlyses reveled tht ge, eduction nd gender hd significnt effects on both HDS-R scores nd MMSE scores ( tble 2 ). These 3 demogrphic fctors ccounted for 22.5 nd 39.7% of the totl vrince of HDS-R scores nd MMSE scores, respectively. Although the demogrphic effect ws significnt in both tests, it ws significntly smller for the HDS-R thn for the MMSE, since the overll R 2 of demogrphic fctors in the regression model of the HDS-R ws significntly smller thn tht of the MMSE (t = 5.58, d.f. = 800, p! 0.001). The mjority of the difference in the overll R 2 between the 2 tests ws ttributed to the difference in the influence of eduction. The prtil R 2 of the eductionl level in the HDS-R (12.4%) ws bout one third of tht in the MMSE (34.9%) (t = 7.94, p! 0.001). The prtil R 2 of ge in the HDS-R ws slightly higher thn tht in the MMSE (t = 2.45, p! 0.05), nd the prtil R 2 of gender in the HDS-R ws comprble to tht in the MMSE (t = 1.24, p ). The regression coefficient of gender for the HDS-R ws lso significntly different from tht for the MMSE (F = 54.80, p! 0.001, Chow test). The performnce of the MMSE ws better in men thn in women, while tht of the HDS-R ws better in women thn in men ( tble 2 ). In the HDS-R, women showed the better performnce on immedite visul recll (t = 2.21, p! 0.5) nd ctegoricl verbl fluency (t = 6.83, p! 0.001). The Person correltion coefficients were between ge nd eduction (p 1 0.1), between ge nd gender (p! 0.001), nd between gender nd eduction (p! 0.001). However, the tolernces were much higher thn 0.2 (ge = 0.965, gender = 0.765, eduction = for the HDS-R; ge = 0.967, gender = 0.754, eduction = for the MMSE) nd VIPs were much lower thn 10 (ge = 1.036, gender = 1.307, eduction = for the HDS-R; ge = 1.304, gender = 1.326, eduction = for the MMSE), indicting tht multicollinerity ws not problemtic. Three-wy ANOVA ws performed in order to determine ny min effects or interctions between ge, eductionl level nd gender on HDS-R scores. The min effects of ge (F[2,778] = 11.36, p! 0.001), eductionl lev- T b l e 1. Chrcteristics of the subjects Vrible Mle Femle Totl Number Age, yers * (41.9) 209 (47.5) 361 (45.0) (38.0) 186 (42.3) 324 (40.3) (20.1) 45 (10.2) 118 (14.7) Eduction, yers * (7.4) 162 (36.8) 189 (23.5) (19.3) 133 (30.2) 203 (25.3) (13.8) 39 (8.9) 89 (11.1) (23.4) 67 (15.2) 152 (18.9) (36.1) 39 (8.9) 170 (21.2) Figures in prentheses re percentges. * p < 0.001, Student s t test. T b l e 2. Stepwise multiple liner regression of ge, eduction nd gender on HDS-R score HDS-R MMSE B SE(B) R 2 B SE(B) R 2 Eduction * 12.40b * Age * * 3.10 Gender *, c * 1.70 * p < 0.001, by stepwise multiple regression nlyses for the HDS-R nd MMSE. p < 0.05; b p < 0.001, by t sttistics compring R of HDS-R nd MMSE; c p < 0.001, Chow test compring of HDS-R nd MMSE. B = Regression coefficient; SE(B) = stndrd error of B; = stndrdized regression coefficient; R 2 = percent vrince explined by ech vrible. 290 Dement Geritr Cogn Disord 2007;24: Jeong /Kim /Lee /Lee /Prk /Choi /Choe / Do /Ryng /Roh /Prk /Choi /Woo

4 T b l e 3. Normtive dt of the HDS-R for men Eduction, yers Age, yers number men SD medin th percentile th percentile b number men SD medin th percentile th percentile c number men SD medin th percentile th percentile Normtive dt from ge group yers. b Normtive dt from ge group yers. c Normtive dt from ge group yers. T b l e 4. Normtive dt of the HDS-R for women Eduction, yers Age, yers number men SD medin th percentile th percentile b number men SD medin th percentile th percentile c number men SD medin th percentile th percentile Normtive dt from ge group yers. b Normtive dt from ge group yers. c Normtive dt from ge group yers. el (F[3,777] = 15.98, p! 0.001), nd gender (F[1,779] = 8.63, p! 0.05) were ll significnt. As expected, the men HDS-R scores were higher in the younger nd more educted nd in women. No interctions were found between the demogrphic vribles. Since the min effects of ge nd eduction were significnt, post-hoc contrsts with Scheffé s method were performed between the ge groups (55 69, 70 79, nd 80 94) nd the eductionl groups (0 6, 7 9, 10 12, nd 6 13 yers). The 3 ge strt were grouped into 3 subsets (55 69, 70 79, nd 80 94), nd the 4 eductionl levels were grouped into 3 subsets (0 6, 7 12, nd 6 13 yers) by the post-hoc tests. On the bsis of the nlysis for the effect of demogrphic vribles, we decided to strtify the norm of the HDS-R by ge, eduction nd gender. To mximize the quntity of informtion nd clinicl usefulness of the dt, the ge groups were divided into 3 overlpping strt (55 74, 64 84, yers) with midpoint ges occurring t 10-yer intervls (64, 74, 84 yers). As result, the normtive dt from the ge groups of 55 74, nd yers were used for persons with ges rnging from 60 69, nd yers, respectively. Considering the results of the post-hoc comprison between the 4 eductionl groups, these groups were divided into 3 strt (0 6, 7 12 nd 6 13 yers). The gender groups were divided into 2 strt (men, women). The HDS-R scores strtified by ge, eduction nd gender re presented s mens 8 stndrd devition, medins nd rnges from the 5th to the 95th percentile ( tbles 3 nd 4 ). Discussion It hs been consistently reported tht the performnce of the MMSE is significntly influenced by demogrphic fctors such s ge, eduction nd gender [4]. Prticulrly the influence of eduction on the performnce of the MMSE significntly limited the use of MMSE s dementi-screening test [4, 10]. In the present study, HDS-R scores were significntly correlted with MMSE scores, nd were lso influenced by demogrphic fctors including ge, gender nd eduction. However, the HDS-R ws much less influenced by demogrphic fctors thn the MMSE. The R 2 of the demogrphic fctors, which represent the proportion of the totl score vrince explined by demogrphic fctors, ws much smller in the regression model for the HDS-R (22.5%) thn in tht for the MMSE (39.7%). Prticulrly the HDS-R ws found to be A Normtive Study of HDS-R Dement Geritr Cogn Disord 2007;24:

5 much more robust to the influence of eduction thn the MMSE, which is in ccord with our previous observtion tht the dignostic ccurcy for dementi of the HDS-R vried much less thn tht of the MMSE with regrd to the eductionl level [10]. Summing up, the HDS-R my be better thn the MMSE for screening dementi, especilly in the lest developed nd developing countries where the rnge of the eductionl level of the popultion is very wide. Interestingly, the influence of gender on the HDS-R ws opposite to tht on the MMSE. Men performed better thn women in the MMSE, wheres women performed better in the HDS-R. In the HDS-R, the gender difference ws lrgest in the ctegory verbl fluency, in which the subjects re sked to sy s mny nmes of vegetbles s possible within 1 min. Considering tht the influence of gender ws differentil ccording to the ctegory used in the verbl fluency tests [26, 27], this gender difference in the verbl fluency of the HDS-R my be, t lest in prt, ttributed to the Est Asin culture. In the previous studies, men performed better in the profession ctegory [26], nd women performed better in the fruit ctegory [27]. In the niml ctegory, no gender difference ws found [27 29]. Since men rrely ttend to household ffirs in Est Asin countries including Kore, women tend to be more fmilir with the nmes of vegetbles thn men, which might hve contributed to the better performnce of women in semntic verbl fluency in the vegetble ctegory. Since the demogrphic influence on HDS-R performnce ws mild but sttisticlly significnt, we estblished normtive dt for the HDS-R. In estblishing the normtive dt, we dopted the overlpping ge strtifiction method to resolve the limited smple size of ech cell [25]. This procedure enbled us to present more strtified nd more ccurte normtive dt tbles with dequte numbers of subjects for most normtive cells. Although the normtive dt in ech ge-overlpping tble were estimted from broder ge rnge tht overlps with n djcent one, these dt cn be pplied to people within nrrow nonoverlpping ge rnge. The users of these normtive dt cn refer to the title of ech normtive tble showing the pplicble ge rnge [22]. Even fter dopting the overlpping strtifiction, the normtive cell for the women ged 80 yers or over nd educted 13 yers or over still hd limited smple size (n = 7). Since smll smple size increses the stndrd errors nd possibly reduces the stbility of the estimted results, users should be more cutious when interpreting the test scores of individuls within this cell. The lck of highly educted oldest-old women in our popultion cn lso be ttributed to Koren culture. Until the erly 1900s, it ws very hrd for most women to receive forml eduction in Kore. Our study hs couple of strengths in providing normtive informtion of the HDS-R. First, both cognitive disorders, including very mild dementi (CDR = 0.5), nd mjor psychitric disorders very prevlent in elderly popultions were strictly excluded through structured evlutions. Therefore, these normtive dt re not likely to be confounded by ptients misclssified s norml elderly. Second, the rnge of eductionl level of the subjects ws wide enough to rnge evenly from the noneducted to the post-grdute levels. Therefore, these normtive dt cn be used both in developing countries, where substntil proportion of the elderly popultion is still undereducted, nd in developed countries, where the mjority of the elderly popultion is well educted. In summry, we confirmed the demogrphic influence on the performnce of the HDS-R nd reported its ge-, gender- nd eduction-specific normtive informtion, which my ssist clinicins nd reserchers both in their selection of dementi screening tools pproprite for the trget popultion nd in their interprettion of the HDS-R. Acknowledgements This work ws supported by n Independent Reserch Grnt from Pfizer Globl Phrmceuticls (grnt No ) nd the Grnt for Developing Seongnm Helth Promotion Progrm for the Elderly from the Seongnm City Government, Kore (grnt No ). References 1 Rosen WG, Mohs RC, Dvis KL: A new rting scle for Alzheimer s disese. Am J Psychitry 1984; 141: Mttis S: Mentl sttus exmintion for orgnic mentl syndrome in the elderly ptient; in Bellck L, Krsu TB (eds): Geritric Psychitry. New York, Grune & Strtion, Folstein MF, Folstein SE, McHugh PR: Minimentl stte. A prcticl method for grding the cognitive stte of ptients for the clinicin. J Psychitr Res 1975; 12: Mlloy PF, Cummings JL, Coffey CE, Duffy J, Fink M, Luterbch EC, Lovell M, Royll D, Sllowy S: Cognitive screening instruments in neuropsychitry: report of the Committee on Reserch of the Americn Neuropsychitric Assocition. J Neuropsychitry Clin Neurosci 1997; 9: Dement Geritr Cogn Disord 2007;24: Jeong /Kim /Lee /Lee /Prk /Choi /Choe / Do /Ryng /Roh /Prk /Choi /Woo

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