原著

West Kyushu Journal of Rehabilitation Sciences：− ，Relationship between instrumental activities of daily living andself-rated health rehabilitation users
Hiroya Miyabara）

Makoto Uchinoura

Moemi MatsuoAbstract））

Yuki Kishikawa

Seijiro Nishimura））

Yuji Yamaguchi

Shinichi Shibata））

Youhei Komatsu

Hajime Shibata））

In general, elderly persons with limitations in instrumental activities of daily liv-ing (IADL) are fragile, due to their various health problems such as disorders, poor cognitive functions. Physical and cognitive status could be predictors for the onset of IADL limitation in elderly persons. On the other hand, self-rated health (SRH), a valid generic healthmeasurement is used as a resource and as an outcome, also was reported as a reliablemeasurement because it was verified that results of SRH and mortality were correlated.
Thus, it can be deemed as a resource which affecting inclusive and dynamic health behavior, and reflecting measure of health status. Therefore, our main objective was to clarify relationships between limitation of IADL levels, SRH, and Mini-Mental State Examination(MMSE) among elderly persons who use ambulatory rehabilitation. As the result, IADL
limitation was related to the level of SRH, but not with MMSE scores.
Key words：Instrumental activities of daily living, Self-rated health, Rehabilitation users,
The long-term care insurance

Introduction

who were not given LTCI certification.

The long-term care insurance (LTCI) system in

One preventive service (service “C”) aims to gain

Japan provides one of seven services (support level 1-2

intensive improvement in participantsʼ activities ofand care levels 1-5) to elderly persons depending on re-daily living, instrumental activities of daily living

1)

cipientsʼ disease condition or functional ability . LTCI(IADL), and physical fitness over a short term of 3 to 6

care levels require more care than support levels, andmonths; the service program is reviewed each 3

the higher level require more severe cares.

month at least2).

LTCI certification levels are defined for example,

In general, elderly persons with limitations in

support level 1 “limited in instrumental activities of

IADL limitations are fragile, due to their various

daily living”. Preventive services are programs for in-health problems, such as disorders (e.g., histories ofdividuals who were not certified as having disabilities,

heart disease, stroke, depression, or diabetes), poor

neither need support level 1-2 of LTCI, thus for thosecognitive functions, and frequent falls3). Physical and

受付日：令和 年 月 日，採択日：令和 年 月 日）Faculty of Rehabilitation Sciences Nishikyushu University, 4490-9 Ozaki, Kanzaki, Saga, 842-8585, Japan. Tel+81-952-52-4191.
）Kabutoyama M S Limited Company R, 1939-1 Toyota Yamamoto Town, Kurume City, Fukuoka Prefecture, 839-0827, Japan. Tel+81942-48-0111.
）Faculty of Health and Social Welfare Sciences Nishikyushu University 4490-9 Ozaki, Kanzaki, Saga, 842-8585, Japan. Tel+81-952-524191.
）Kurume Rehabilitation Hospital 1887 Toyota Yamamoto Town, Kurume City, Fukuoka Prefecture, 839-0827, Japan. Te+81-942-438033.

Relationship between instrumental activities of daily living and self-rated health rehabilitation users

cognitive status could be predictors for the onset ofJapanese Ministry of Health, Labour and Welfare ）.

IADL limitation in elderly persons4). On the other hand,

The three sub-items are as follows: (1) using bus or

SRH which is a valid generic health measurement istrain by own self, (2) buying daily necessities by own-

used as a resource (e.g., as a restriction or prerequisite

self, (3) managing own deposits and savings at thefor social participation) and as an outcome (e.g., as anbank by ownself. Cognitive function was assessed us-index for health preservation or health improvement),ing 30-questions of MMSE; each correct answer wasalso was reported as a reliable measurement because

scored by one point, whereas incorrect or no answers

it was verified that results of SRH and mortality werewere scored as zero point. The total score ranged

correlated. Thus, it can be deemed as a resourcefrom 0 to 30 points.

which affecting inclusive and dynamic health behavior,and reflecting measure of health status. 5). However,few studies have examined about relationships be-

The statistical analysis software SPSS (Versiontween IADL items, cognitive functions, and SRH

26.0, SPSS Inc., Chicago, IL, USA) was used for statisti-amongst persons who use ambulatory rehabilitation.

cal analysis. In this study, all continuous variables

Previous studies, moderate participation in neigh-were presented as the mean

standard deviation (SD)borhood community associations were more favorable

and categorical data were presented as numbers (per-for the maintenance of IADL among female than male.

centages). Pair analyses were carried out using un-

Because female participants often participate in invol-

paired Studentʼs t-tests. Correlations were analyzed

6)

untary neighborhood community association .

by Pearsonʼs correlation coefficient among continuous

Therefore, our objective was to clarify relation-variables. Chi-square tests were used to compare dif-ships between limitation of IADL levels and SRH,

ferences in limitation of IADL level. Differences with aMMSE among elderly persons who use ambulatory re--value of <0.05 were considered statistically signifi-habilitation.

cant.

Materials Methods

Results
Table 1 provides an overview of the participants

Thirty-six elderly persons (11 males and 25 females, aged 81.3

(n=36). Seventy-eight percentages of the participants

5.7 years) who use ambulatory re-needed support 1 and twenty-two percentages of thehabilitation participated in this study. The present in-participants needed support 2 Sixty-one percentages

vestigation was approved by Kurume Rehabilitationof the participants were with IADL limitation. Fe-

Hospital Ethical Review Board for Medical Researchmales had significantly higher age (p<0.05) and IADL

involving Human Subjects (ethical number: 21-001),(p<0.05) than males (Table 2). Pearsonʼs correlationand this work was supported by the Kabutoyama M S

analysis revealed that IADL scores was negatively as-

Limited Company R, Japan. Collected data included

sociated with age (r=-0.41, p<0.05) and positively asso-

the sociodemographic characteristics (e.g., gender, age,ciated with SRH (r=0.41, p<0.05) (Table 3). Table 4

educational background), anthropometric measure-shows the results of IADL limitation in participants

ments (e.g., height, weight), health status, personal hab-

who reported subsequent activity limitation. Rate ofits. Body mass index (BMI) was calculated by dividing

subsequent activity limitation significantly differed be-the weight (kilogram) by height (meter squared).

tween male and female in regard to buying daily necessities (p<0.05) and managing deposits and savings(p<0.05).

IADL limitation was assessed using three subitems of the Kihon-Checklist ） and a self-reported comprehensive health checklist that was developed by theRelationship between instrumental activities of daily living and self-rated health rehabilitation users

Table 1 Demographic characteristics of participantsDemographic
Characteristics(n=36)

Mean SD

Numbers (%)

Table 2 Comparison of characteristics between male and female
Variables

Male(n=11)

Female(n=25)

P-valueAge (years)

78.0 7.3

82.8 4.1

0.04*

Age (years)

81.3 5.7

36 (100)

BMI

24.6 3.4

23.5 4.1

0.43

Male (age, years)

78.0 7.3

11 (31)

Education (years)

10.9 1.5

10.4 1.5

0.40

Female (age, years)

82.8 4.1

25 (69)IADL (score)

1.1 1.1

2.2 0.8

0.02*

MMSE (score)

25.2 4.1

26.7 2.3

0.19

Junior school­17 (47)

Self-rated health (score)

2.3 0.92

2.7 0.96

0.28

High school­

19 (53)*p<0.05 by Pearsonʼs correlation

Needs support 1­

28 (78)

Table 3 Correlations between variables and IADL scores

Needs support 2­

8 (22)

Variables­8 (22)

Educational background

Level of care needed

Types of diseases
Cerebrovascular disorders
Bone and joint disorders

P-valuer

Age

0.02*

0.89

Gender

­0.41

0.02

­

5 (14)

education

0.01*

0.94

­

1 (3)

BMI

0.15

0.94

Hypertension­17 (47)

MMSE

0.37

0.05

Diabetes mellitus­4 (11)

Self-rated health

0.41

0.03

Hyperlipidemia

­

1 (3)

*p<0.05 by Pearsonʼs correlation

Heart disorders

IADLIndependent­

14 (39)Limitation­22 (61)high or low cognitive demand ）. An earlier study proposed that elderly persons experience greater diffi-MMSE(scores)≦26

20 (56)culty in performance of IADLs that involve higher27≧

16 (44)

cognitive demand ）. This study suggests that cogni-

Self-rated health (scores)

tive function including memory and processing speed≦3­

16 (47)may be an important factor in maintaining IADLs2≦­18 (53)such as using transportation, shopping, and managing
finances in later life. Moreover, being reluctant for eld-Discussion

erly persons who use ambulatory rehabilitation may

This study focused on the effect of IADL limita-

be a premonitory symptom of IADL limitations. Hence,tion and SRH, MMSE of elderly persons. Two main re-

we should take great care if generalizing our findings

sults were found. First, there was relationship be-in elderly persons with functional disabilities, espe-

tween IADL scores and SRH. Second, there was a sig-cially among people who living in rural areas or coun-nificant difference in rate of subsequent activity be-

try side with different cultural background.

tween male and female with regard to buying daily necessities and managing deposits and savings.

Our study has several limitations. First, we did
not achieve adequate response and follow-up rates.

This study analyzed determining whether elderly

Second, this study is a prospective cohort study, andpersons had onset experiences of declining three kind

there may be potential of reverse causation. Finally,of IADLs, including using transportation, shopping,

the study population of this study comprised only inand managing finances. In terms of the other IADLs

elderly persons who had independent IADL with base-such as cooking, housekeeping, and handling medica-line and were living in a commuter town in Japan.

tion, these activities are also necessary for the mainte-Thus, it is not certain if this results can be generaliz-nance of independence in elderly persons. In addition,

able in other population or persons who live in otherprevious studies have divided IADLs into two catego-areas.

ries based on differences between activities involving

In conclusion, our present findings demonstrated

Relationship between instrumental activities of daily living and self-rated health rehabilitation users

Table 4 Comparison of characteristics between participants with and without self-reported IADL limitation
No. of IADL limitation(n=36)

Male (n=11)

Female (n=25)

p-Value

Using bus or train by ownself

14 (38.8)

8 (72.7)

14 (56.0)

0.24

Going out and buying daily necessities
by ownself

28 (77.7)

6 (54.5)

2 (8.0)0.002*

Managing own deposits and savings atthe bank25 (69.4)

7 (63.6)

4 (16.0)

0.03*

IADL items
Subsequent activity limitation (number ofparticipants)*p<0.05 by Chi-square tests

relationships between IADL limitation and SRH.
These suggest may be an important factor in maintaining IADLs such as using transportation, shopping,2)

and managing finances in later life.
Acknowledgments
The authors would like to thank all of participants

3)of this study.
Conflicts of Interest
The authors have read the journalʼs policy and4)

have the following conflicts; Authors of the present
study, Makoto Uchinoura, Seijiro Nishimura andShinichi Shibata are employees of Kabutoyama M S
Limited Company R. However, the sponsor had no role5)in the study design, data collection and analysis, neither decision to publish, nor preparation of the manuscript. There are no patents, products in development

6)

or marketed products to declare. The authors declareno competing interests. Thus, there is no conflicts ofinterest relevant to this article.

7)

Author Contributions
HM conceptualized the study design and protocol.
HM, MU, YK, YY, SN, SS collected the data. HM andYK carried out the analysis and interpretation of data.
HM, HS and MM drafted the manuscript. All authors

8)

have critically reviewed, revised and approved themanuscript.
9)
References
1) Ministry of Health, Labour and Welfare. Long-Term Care
Insurance System of Japan: Ministry of Health, Labour andWelfare. 2016.
https : / / www. mhlw. go. jp / english / pollcy / care-welfareelderly/dl/ltcissj-e.pdf. Accessed 1 Sep 2021.
Ministry of Health, Labour and Welfare. Outline of Prevent
Long-Term Care Need and Daily Living Service Projects:
Ministry of Health, Labour and Welfare. 2016.
https : / / www. mhlw. go. jp / file / 06-Seisakujouhou-12300000Roukenkyoku/0000088276.pdf. Accessed 1 Sep 2021.
Nourhashemi F, Andrieu S, Gillette GS, Vellas B, Albarede
JL, Grandjean H. 2001. Instrumental activities of daily living
as a potential marker of frailty: A study of 7364 communty
dwelling elderly women (the epidos study). J Gerontol A Biol
Sci Med Sci 56: M 448-M 453. doi: 10.1093/gerona/56.7.m 448
Lee Y. 2000. The predictive value of self assessed general,physical, and mental health on functional decline and mortality in older adults. J Epidemiol Commnunity Health 54: 123129. doi: 10.1136/jech.54.2.123
Benyamini Y. 2011. Why does self-rated health predict mortality? An update on current knowledge and a research
agenda for psychologists. Psychol. Health. 56(11): 1407-1413.
doi: 10.1080/08870446.2011.621703
Iwasaki M, Otani T, Sunage R, Miyazaki H, Xiao L, Wang N,
Sasazawa Y, Suzuki S. 2002. Social networks and mortality
based on the Komo-ise cohort study in Japan. Int J Epidemiol 31:1208-1218. doi.org/10.1093/ije/31.6.1208
Fukutomi E, Okumiya K, Wada T, Sakamoto R, Ishimoto Y,
Kimura Y, Kasahara Y, Chen WL, Fujisawa M, Otuka K,
Matsubayashi K. 2013. Inportance ofcognitive assessment as
part of the “Kihon checklist” developed by the Japaneseministry of health,Labor and welfare for prediction of frailty
at a 2-year follow up. Geriatr Gerontol Int 13: 654-662. doi.org/10.1111/j.1447-0594.2012.00959.
Ministry of Health, Labour and Welfare. The Latest Information of Long-Term Care Insurance. 2010. https://jamcf.jp/instiution/2010/kaigohokeninfo 158.pdf. Accessed 15 Sep
2020.
Reppermund S, Brodaty H, Crawford JD, Kochan NA,Draper B, Slavin MJ, Trollor JN, Sachdev PS. 2013. Impairment instrumental activities of daily living with high cognitive demand is an early marker of mild cognitive impairment: The sydney memory and ageing study. Psychol Med

Relationship between instrumental activities of daily living and self-rated health rehabilitation users

43:2437-2445. doi: 10.1017/S 003329171200308 X10) Reppermund S, Sachdev PS , Crawford JD, Kochan NA,Slavin MJ, Kang K, Trollor JN, Draper B, Brodaty H. 2011.
The relationship of neuropsychological function to instrumental activities of daily living in mild cognitive impairment.
Int J Geriatr Psychiatry 26:843-852. doi: 10.1002/gps.2612