Archives of Gerontology and Geriatrics 91 (2020) 104237

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Change in the prevalence of social isolation among the older populationfrom 2010 to 2016: A repeated cross-sectional comparative study of Japanand England
Taishi Tsuji a, b, *, Masashige Saito c, Takaaki Ikeda d, e, Jun Aida f, g, Noriko Cable h,
Shihoko Koyama i, Taiji Noguchi j, k, Ken Osaka e, Katsunori Kondo b, kaFaculty of Health and Sport Sciences, University of Tsukuba, 3-29-1 Otsuka, Bunkyo City, Tokyo 112-0012 Japan
Center for Preventive Medical Sciences, Chiba University, 1-8-1 Inohana, Chuo Ward, Chiba City, Chiba 260-8670 Japanc
Department of Social Welfare, Nihon Fukushi University, Okuda, Mihama-cho, Chita-gun, Aichi 470-3295 Japand
Graduate School of Medical Science, Yamagata University, 2-2-2 Iida-Nishi, Yamagata City, Yamagata 990-9585 Japane
Department of International and Community Oral Health, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba Ward, Sendai City, Miyagi 9808574 Japanf
Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo City, Tokyo 113-8549 Japang
Liaison Center for Innovative Dentistry, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba Ward, Sendai City, Miyagi 980-8574 Japanh
Department of Epidemiology and Public Health, University College London, 1-19 Torrington Place, London WC1E 6BT United KingdomiCancer Control Center, Osaka International Cancer Institute, 3-1-69 Ohtemae, Chuo Ward, Osaka 541-8567 Japanj
Department of Public Health, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho Ward, Nagoya City, Aichi 467-8601 JapankCenter for Gerontology and Social Science, National Center for Geriatrics and Gerontology, 7-430 Morioka-cho, Obu City, Aichi 474-8511 Japanb

A R T I C L E I N F O

A B S T R A C T

Keywords:
National comparison
Social interaction
Social participation
Solitary death

Objective: To compare the change in the prevalence of social isolation from 2010 to 2016 between older pop­
ulations in Japan, the most aging and socially isolated country, and England, a country known for advancedsocial isolation measures.
Methods: Surveys from the Japan Gerontological Evaluation Study (JAGES) and the English Longitudinal Study ofAging (ELSA) included 70,751 and 4134 participants, respectively, aged 65 years or older in 2010 and 94,228
and 4295 participants in 2016. We assessed the social isolation of respondents on a scale from 0 to 5 points basedon lack of social interactions with a spouse or partner, children, relatives, or friends and nonparticipation in any
organization.
Results: Results of two-way analysis of variance confirmed significant interactions (nation × period) in men andwomen aged 65–74 years and women aged 75 years or older. In JAGES, all had higher scores in 2016 compared
to 2010 (1.64–1.76, 1.28–1.36, and 1.55–1.60 points, respectively). Furthermore, the proportions of those withlack of interaction with relatives increased (52.7%–58.9%, 31.5%–41.1%, and 25.2%39.2%, respectively). In
ELSA, women aged 75 years or older demonstrated a significantly lower mean score in 2016 than in 2010 (1.40
vs. 1.21). No significant changes were observed in other groups.
Conclusion: Social isolation among older adults is more severe in Japan than in England. The difference has
widened, especially for women and younger older adults. This is attributed to the weakening relationships withrelatives in Japan.

1. Backgroundstructural aspects such as social networks/participations and functional
aspects such as social support that is the resource social network brings(Antonucci & Akiyama, 1987). Enhancing structural aspects of social
relationships could enrich social support, in turn bringing various healthbenefits (Cohen, 2004; Holt-Lunstad, Smith, Baker, Harris, &Social isolation is generally defined as a state in which objectively
quantifiable social interactions, contacts, and networks are absent (deJong Gierveld & Havens, 2004). Social relationships are composite of* Corresponding author at: Faculty of Health and Sport Sciencesm, University of Tsukuba 3-29-1 Otsuka, Bunkyo City, Tokyo 112-0012 Japan.
E-mail address: tsuji.taishi.gn@u.tsukuba.ac.jp (T. Tsuji).
https://doi.org/10.1016/j.archger.2020.104237
Received 11 May 2020; Received in revised form 4 August 2020; Accepted 18 August 2020
Available online 22 August 20200167-4943/© 2020 The Author(s).
Published by Elsevier B.V. This is an(http://creativecommons.org/licenses/by-nc-nd/4.0/).

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Archives of Gerontology and Geriatrics 91 (2020) 104237

Stephenson, 2015). In this sense, social isolation is broadly regarded as astate of poor social relationship that addresses both structural andfunctional aspects (Mehrabi & Beland, 2020).
Older adults are at a higher risk for social isolation (Iliffe et al.,2007); and globally, up to 50% of this population category are at risk ofsocial isolation (Landeiro, Barrows, Nuttall Musson, Gray, & Leal, 2017).
Recent empirical studies have reported that social isolation adversely
affects various health outcomes (Mehrabi & Beland, 2020; Petersen,
Konig, & Hajek, 2020), whereas the influence of adequate social re­lationships on risk for mortality is comparable with quitting smoking(Holt-Lunstad, Smith, & Layton, 2010). Studies examining relationships
between social isolation and health among older adults are accumulated
year by year, and the importance of prevention of social isolation andimprovement of social relationships is being emphasized in each report(Fakoya, McCorry, & Donnelly, 2020; Mehrabi & Beland, 2020). How­ever, most of those reports are based on localized analyses at the indi­vidual level, with few reports investigate how the prevalence of social
isolation among the older adults has changed in recent years at the
population level.
In Japan, where a super-aging society is advancing, social isolation
among older adults is among the most important issues in public health.
For instance, from 2000 to 2015, the never-married rate has rapidly
increased 2 times for men (from 12.6% to 23.4%) and 2.5 times for
women (from 5.8% to 14.1%) (National Institute of Population & Social
Security Research, 2017). In the same period, the number of older adults
living alone has almost doubled from 3 million to 6 million (Cabinet
Office, Government of Japan, 2019). Older adults who are at higher riskof social isolation, such as the unmarried or those living alone, are more
likely to experience solitary death (Gurley, Lum, Sande, Lo, & Katz,
1996; Kakiuchi, Nagao, Ochiai, Kakimoto, & Osawa, 2019). Actually, inthe urban area of Tokyo, the number of solitary death among older
adults has increased approximately 1.5 times during the past decade(Cabinet Office, Government of Japan, 2019). However, the detailed
picture and trends of this multifaceted social isolation from structur­
al/functional perspectives, including friendship and social participation
among older adults nationwide in Japan, are not fully understood.
In contrast, the United Kingdom (UK) is one of the country’s mostenthusiastically working on countermeasures regarding this topic. The
government of the UK published a policy paper, “A Connected Society: A
Strategy for Tackling Loneliness,” in 2018 examining the social issues
caused by loneliness and social isolation (HM Government, 2018). In ascoping review that systematically searched for reviews on interventions
for social isolation and loneliness in older adults, authors found threetimes more intervention studies from the UK than studies from Japan(Fakoya et al., 2020). However, in the UK, the trends of social isolation
among older adults in recent years are also not well understood. For
instance, the number of older adults living alone, which are classified as
high-risk households for social isolation, is increasing (Office for Na­
tional Statistics, 2019). Surprisingly, multiple-family households, which
are low-risk households are regarded as the fastest growing household
type in the UK (Office for National Statistics, 2019). Furthermore, wecannot find any reports that quantitatively evaluated changes in theprevalence of non-kin social relationships, such as social networks withfriends and participation in local organizations. Both Japan and the UK
are developed and advanced nations with considerable aging population
where preventing social isolation among older people is an urgent need.
However, their devotion to addressing the issue differs, and the change
in recent years in the prevalence is unclear.
This study aims to compare the change in prevalence of social
isolation from 2010 to 2016 between the older populations in Japan andEngland by age and sex groups and to verify which components
contribute to this difference. We hypothesized that, in Japan, social
isolation has been seen to worsen recently as family relationships have
weakened, especially for younger older adults, compared with England.

2. Methods
2.1. Study design and participants
In our comparative repeated cross-sectional study, we obtained two
ongoing prospective aging studies: the Japan Gerontological Evaluation
Study (JAGES) and the English Longitudinal Study of Aging (ELSA).
JAGES, which is panel study with more than 100,000 participants living
in Japan as of 2016, is focused on investigating social and behavioral
factors related to loss of independence with respect to functional
decline, or cognitive impairment, among individuals 65 years or older. A
detailed description of the study has been published elsewhere (Kondo,
2016; Kondo, Rosenberg, & World Health Organization, 2018). Mean­
while, ELSA is a panel study of a nationally representative sample of the
English population living in private households and aged 50 years orolder, which has also been described in detail elsewhere (Banks, Batty,
Nazroo, Oskala, & Steptoe, 2018; Steptoe, Breeze, Banks, & Nazroo,2013). We used the data from the JAGES (three waves: 2010/11, 2013,
and 2016) and ELSA (four waves: 2010/11, 2012/13, 2014/15, and2016/17). Hereinafter, the years that the survey started is indicated for
identifying each survey wave for convenience. From each dataset, in­dividuals with complete sex, age, and social isolation variables and those
aged 65 years or older were selected for this analysis. They were strat­
ified by sex and age (65–74 years and ≥75 years), and the numbers ofanalytic sample in each group were from 12,814 to 28,631 in JAGES andfrom 692 to 1403 in ELSA (Fig. 1). The JAGES protocols were approvedby the Ethics Committee at Chiba University, Japan (Approval number:
2493) and the National Center for Geriatrics and Gerontology, Japan(Approval number: 992). Meanwhile, the ELSA received ethicalapproval for all waves of the study from the National Health Service
Research Ethics Committees under the National Research and Ethics
Service, UK.
2.2. Measurements
The ELSA proposed a 5-point social isolation index consisting of thefollowing components: unmarried/not cohabiting; less than monthly
contact with each of the following: children, other family members,
friends, and nonparticipation in organizations (Shankar, McMunn,
Banks, & Steptoe, 2011; Steptoe, Shankar, Demakakos, & Wardle,
2013). Older adults with higher index scores were more likely to besmokers and physically inactive, have higher blood pressure, and have ahigher risk of all-cause mortality (Shankar et al., 2011; Steptoe, Shankar
et al., 2013). In the present study, a modified version of the index wasused in order to have comparability between JAGES and ELSA. Eachparticipant gets 1 point if (1) not married or cohabitating with a partner;(2) did not live with their children or had no one to provide emotional or
instrumental social support; (3) did not have immediate family members
providing emotional or instrumental social support; (4) had face-to-facecontact with friends less than once a month or did not have any friends
who could provide emotional or instrumental social support; and (5) did
not participate in any organizations, religious groups, or committees.
While the original version of the index did not include providing social
support, we used a modified version including social support that is afunctional aspect of social relationships to make it comparable to
JAGES. The total possible score could range from 0 to 5, with higherscores indicative of greater social isolation.
2.3. Statistical analysis
For each wave in each cohort, we described the mean and standard
deviation of social isolation scores for each sex and age group.
Furthermore, we performed a two-way analysis of variance (nation ×
period) using two-wave data from each cohort collected in approxi­
mately the same period (first wave collected in 2010 and last wave
collected in 2016) to determine the primary effects of nation and period2T. Tsuji et al.

Archives of Gerontology and Geriatrics 91 (2020) 104237

Fig. 1. Number of analytic participants in each cohort study for each survey wave.

Fig. 2. The transition of the mean social isolation score in each sex and age group for each survey wave.
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Archives of Gerontology and Geriatrics 91 (2020) 104237

as well as their interaction. This statistical approach allowed us to es­
timate the cross-sectional difference in the prevalence of social isolation
between Japan and England and how its transition differed in recent
years. If significant interactions (nation × period) were confirmed,
simple main effects were tested using the Bonferroni correction. In
addition, to determine which component caused the difference, we
described the proportions of the individuals assigned 1 point in each of
the five items constituting the social isolation score in each wave of 2010
and 2016 in each cohort. All tests were two-tailed, with differences re­ported as significant if the P-value was less than 0.05.
To explore potential cohort period effects, we conducted the same
analysis by tracing the birth cohort as a sensitivity analysis. For instance,
we compared the group of participants aged 65–74 years in 2010 withthe group aged 71–80 years in 2016. This comparison focuses on vari­ations resulting from the unique experience and exposure of a cohort asthey move across time. All analyses were performed using Stata/MP
14.2 (Stata Corp., College Station, TX).

the difference between Japan and England were the lack of social
interaction with children, relatives, and friends. Those were approxi­
mately twice or more frequent in JAGES compared to ELSA, except for
women aged 75 years or older. Focusing on the changes from 2010 to2016, a common feature seen only in JAGES was that the number ofindividuals who did not receive support from relatives except spouses
and children increased (6.2%–14.0%). The only other item confirmed toincrease by 5% or more was non-participation among men aged 65–74
years in JAGES (from 27.6%–34.2%). In contrast, ELSA did not havesuch an item. ELSA showed a flat or gradually declining trend for mostcomponents in all gender and age groups. If we dare mention the com­ponents that showed an increasing trend, it would be the lack of inter­action with relatives (from 21.4% to 25.9%) and spouse/partner (from26.5 to 29.3%) in men aged 75 years or older.
4. Discussion
The main findings of this study are as follows: (1) social isolation
among older adults is more common in Japan than in England, regard­
less of sex and age; (2) the difference has widened further, especially for
women and younger older adults in recent years; and (3) the main cause
for this widening gap is the weakening relationships with relatives inJapan.
Japan is one of the most socially isolated countries in the world, withapproximately three times more people than in the UK to rarely or neverspend time with friends, colleagues, or others in social groups (OECD,2005). In this study, which limited participants to older adults, JAGES
participants were two to three times more likely to have less interaction
with friends than ELSA participants in both 2010 and 2016, regardless ofsex and age. This could be attributed to the introverted personality thatis common among Japanese people and the context and culture that has
been rooted in Japan over time.
The notable result of this study is that the relationship with relatives(excluding spouses and children) is weaker in Japan than in the UK, and

3. Results
Fig. 2 shows the mean and standard deviation of each wave’s social
isolation score for each cohort for each sex and age group. In the main
analyses, we found significant nation × period interactions in all groups
except for men aged 75 years and older. In those three groups, JAGES
had higher mean scores than ELSA in both 2010 and 2016, and the 2016
JAGES scores were significantly higher than the 2010 JAGES scores. On
the other hand, women aged 75 years or older had a significantly lower
ELSA score in 2016 than in 2010. Overall, men aged 75 years or older
had a higher mean JAGES score than ELSA, and the 2016 score washigher than 2010. In sensitive analyses, we also found similar results,
except that the significant interaction was abolished in the men aged
65–74 years (as of 2010) group (Fig. A1).
Fig. 3 shows the proportions of the individual assigned 1 point ineach of the five items. As of 2010, the major components that induced

Fig. A1. The transition of the mean social isolation score in each sex and age group for each survey wave by tracing generations.
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Archives of Gerontology and Geriatrics 91 (2020) 104237

Fig. 3. The proportions of respondents assigned 1 point (i.e., lack of social interaction) for each of the five items in each sex and age group for the 2010 and2016 surveys.

the difference is further widening. According to Japanese government
statistics (Ministry of Health, Labour & Welfare, 2019), the number ofthree-generation households and those with siblings fell 6.4 percentage
points from 27.4% in 2010 to 21.0% in 2016. Thirty years ago (1986),
these households accounted for 57.5% of all households. This meansthat nuclear families (i.e., parents and children only) have now become
the most common household composition, and the numbers of suchhouseholds have grown rapidly (1% year) in Japan. On the other hand, asimilar phenomenon was not reported in the UK. In this study, there wasno noticeable change in ELSA as compared with JAGES for women andyounger older adults. However, men aged 75 years or older were re­ported to have weakened their relationships with relatives in ELSA. Thisis one of the reasons that no significant interaction was observed be­
tween JAGES and ELSA in this sex and age group. Furthermore, ELSA
shows an increasing trend in social isolation scores only in this group.
We propose that this group might be a priority target population in the
UK’s social isolation measures.
Among women, significant interactions were observed in all ana­lyses, including sensitivity analyses. Although social isolation has
become more severe in JAGES regardless of the age group, the meanscore has leveled off among those aged 65–74 years and has evendecreased among those 75 years and older in ELSA. In this older popu­
lation, all five items were reduced by a few percentage points. This
group might be a population likely to benefit from the multicomponent,
multilayered measures for social isolation, which have been imple­
mented in the UK, for instance, suggested by the Jo Cox Commission on
Loneliness (2017) and the previously mentioned policy paper (HMGovernment, 2018). Although the first annual report on tackling lone­
liness (HM Government, 2020) indicated 60 strategy commitments anda few case studies, it does not yet include a quantitative assessment. In
spite of loneliness was emphasized in the titles of these documents (HMGovernment, 2020; Jo Cox Commission on Loneliness, 2017), they also
described several measures against social isolation.
In considering measures to prevent social isolation, while improving
the quality of social interaction with family and relatives is helpful, thesize of such networks is likely to be exhaustive and increase of the

network size could be impractical at older age. On the other hand, it isexpected that the approach of increasing social participation, which
could be the best modifiable factor. According to a previous
municipality-level ecological study (Watanabe et al., 2019), participa­tion in sports groups and volunteer activities among older adults living
in Japan has increased by approximately 2%–6% between 2010 and2016. Furthermore, it was confirmed that the proportion of older adults
with depressive symptoms decreased in municipalities in which partic­
ipation in sports and hobby groups had increased (Watanabe et al.,2019). According to a report investigating the characteristics of older
sports group participants (Yamakita, Kanamori, Kondo, & Kondo, 2015),
there were many people who participated in socially organized groups
such as hobbies and volunteers, the number of friends and the frequencyof meeting them became larger, and social support also became
enriched. Therefore, further promotion of social participation could be arealistic measure for social isolation with high priority in Japan. As aresult, the exchange with friends and acquaintances will also be accel­
erated, which may bring an advance effect on preventing social isolation
among older adults. There is a movement to introduce the social pre­scribing framework, which is being institutionalized in the UK National
Health Service, in Japan (Nishioka & Kondo, 2020). Social prescribing isa way for local agencies to refer people to a link worker who connects
people to community groups and statutory services for practical andemotional support (NHS England, 2020).
The strength of this study was to compare the trends in social
isolation among older adults using data from a large cohort in Japan andfrom a nationally representative sample in England. This might allow us
to obtain results with highly internal validity. However, there wereseveral limitations. First, we cannot discuss external validity or gener­
alizability. Because social isolation is strongly influenced by the social
background and context of each country, it is not clear whether the
results of this study also apply to other Asian and European countries. In
the future, collecting data from several countries will reveal common ordifferent features in these regions. Second, there might be several biases
resulting from differences in survey design. ELSA mainly conductedinterviews on nationally representative samples, whereas JAGES
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Archives of Gerontology and Geriatrics 91 (2020) 104237

conducted mail surveys on non-nationally representative samples.
Third, the questions and options in the JAGES and ELSA were not exactly
the same, nor were they strictly authorized through procedures such as
reverse translation and confirming reliability and validity. Furthermore,
there is no denying that the meaning and definition of the term “friend”
may differ depending on the culture of the country. However, we believethese biases and limitations would not explain all of the differences inour results. It is meaningful to describe the trend of social isolation
among older adults with a cross-national comparison with the same
framework.

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5. Conclusion
Social isolation among the older population was originally more
serious in Japan than England, and the gap has widened in recent years,
especially for women and younger older adults. Its cause, although thetrend of maintenance and improvement was confirmed in England, wasmainly attributed to the weakening relationships with relatives inJapan. Therefore, England must continue with the strategy it started in2018 for addressing loneliness and social isolation. Likewise, Japan
should also proactively promote initiatives that foster social participa­tion and friendship.
Financial support
This study was supported by JSPS (Japan Society for the Promotionof Science) KAKENHI (Grant Number: JP15H01972, JP16K16595,
JP18KK0057, JP20K19534), Health and Labour Sciences Research
Grants (H28-Choju-Ippan-002, 19FA1012, 19FA2001), Japan Agency
for Medical Research and Development (AMED) (JP17dk0110017,
JP18dk0110027, JP18ls0110002, JP18le0110009, JP19dk0110034,
JP19dk0110037, JP20dk0110034), Open Innovation Platform withEnterprises, Research Institute and Academia (OPERA, JPMJOP1831)
from the Japan Science and Technology (JST), and a grant from Inno­
vative Research Program on Suicide Countermeasures (1–4). The fund­ing sources had no role in study design, data collection and analysis,
decision to publish, or preparation of the manuscript.
Author contributions
Conception and design: TT and MS; data collection: TT and KK;
analysis, interpretation of the data, and writing the article: TT; criticalrevision of the article: MS, TI, JA, NC, SK, TN, KO, and KK. All authors
read and approved the final manuscript.
Declaration of Competing Interest
The authors reported no declarations of interest.
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