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Effect of social networks on 10 year survival in very old Australians: The Australian longitudinal study of aging


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To examine if social networks with children, relatives, friends, and confidants predict survival in older Australians over 10 years after controlling for a range of demographic, health, and lifestyle variables. Prospective longitudinal cohort study (the Australian longitudinal study of aging) Adelaide, South Australia. 1477 persons aged 70 years or more living in the community and residential care facilities. After controlling for a range of demographic, health, and lifestyle variables, greater networks with friends were protective against mortality in the 10 year follow up period. The hazard ratio for participants in the highest tertile of friends networks compared with participants in the lowest group was 0.78 (95%CI 0.65 to 0.92). A smaller effect of greater networks with confidants (hazard ratio = 0.84; 95%CI = 0.71 to 0.98) was seen. The effects of social networks with children and relatives were not significant with respect to survival over the following decade. Survival time may be enhanced by strong social networks. Among older Australians, these may be important in lengthening survival.
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Effect of social networks on 10 year survival in very old
Australians: the Australian longitudinal study of aging
Lynne C Giles, Gary F V Glonek, Mary A Luszcz, Gary R Andrews
See end of article for
authors’ affiliations
Correspondence to:
Ms L C Giles, Department
of Rehabilitation and Aged
Care, Flinders University,
GPO Box 2100, Adelaide,
South Australia 5001,
Australia; Lynne.Giles@
Accepted for publication
23 November 2004
J Epidemiol Community Health 2005;59:574–579. doi: 10.1136/jech.2004.025429
Study objectives: To examine if social networks with children, relatives, friends, and confidants predict
survival in older Australians over 10 years after controlling for a range of demographic, health, and
lifestyle variables.
Design: Prospective longitudinal cohort study (the Australian longitudinal study of aging)
Setting: Adelaide, South Australia.
Participants: 1477 persons aged 70 years or more living in the community and residential care facilities.
Main results: After controlling for a range of demographic, health, and lifestyle variables, greater
networks with friends were protective against mortality in the 10 year follow up period. The hazard ratio
for participants in the highest tertile of friends networks compared with participants in the lowest group
was 0.78 (95%CI 0.65 to 0.92). A smaller effect of greater networks with confidants (hazard ratio = 0.84;
95%CI = 0.71 to 0.98) was seen. The effects of social networks with children and relatives were not
significant with respect to survival over the following decade.
Conclusions: Survival time may be enhanced by strong social networks. Among older Australians, these
may be important in lengthening survival.
ver the past quarter century, epidemiological studies
conducted in the USA,
and Asia
17 18
have generally, but not always,
shown that social
relationships have beneficial effects on survival in adults. The
convergence in findings is impressive given that the follow up
time in these studies has ranged from two
to 17 years,
sample sizes have ranged from several hundred
to more than
17 000 participants,
11 12
and the participants’ ages have varied
from 18 to 94 years. Despite the general consensus of positive
effects of social relationships upon survival, several questions
remain unanswered concerning the effects of social relation-
ships on mortality in older people.
Firstly, it is unclear if all social relationships are equally
beneficial to survival among older people or if specific types
of relationship are more advantageous. Research by Seeman
et al
suggested ties with close friends or relatives, or both,
may protect against mortality in older people. However, this
work did not distinguish between ties with friends compared
with relatives. Little other research has distinguished
between the effect of kin and non-kin, or discretionary,
social relationships on mortality.
Secondly, most research concerning social relationships
and mortality has been conducted in North America. Four
studies cited above that found no effects of social relation-
ships on survival used Australian data.
Some of these
studies were small
or used a narrow range of measures of
social relationships,
so it is possible that their findings were
attributable to methodological features rather than the true
absence of an effect of social relationships upon mortality.
For example, a comprehensive study by Korten et al
included variables concerning social integration and avail-
ability of attachments, but did not differentiate between
types of social relationships. Similarly, McCallum and
considered emotional social support and social
participation as potential predictors of survival over seven
years of follow up, but again did not consider different types
of social relationships.
Thirdly, some authors have reported a threshold of social
relationships above which little survival advantage is
We have found no research that has formally
tested the hypothesis of threshold effects of specific types of
social relationships upon mortality, and only one study that
considered threshold effects included older participants.
Finally, social relationships have been defined in many
Many studies have used single variables that purport
to measure social relationships, but do not capture the wider
social integration of an individual. Four composite measures
of social networks were recently developed by Glass et al
using data from a large US longitudinal study of aging. These
specific social network measures incorporated the structure
and specificity of network ties with children, other relatives,
friends, and confidants. The measures were designed to aid in
identifying the most ‘‘health-beneficial’’ social relationships
for older people,
and to overcome many of the problems
inherent in epidemiological studies that have examined the
effects of social relationships upon health.
We validated the measurement model developed by Glass
et al using data from the Australian longitudinal study of
aging (ALSA).
The resulting measures of specific social
networks are used in this study. The aims of this study were
to (1) assess the effects of specific social networks on 10 year
mortality in older Australians and (2) test for the existence of
a threshold effect of different types of social networks on 10
year mortality.
We drew data from the ALSA that began in 1992 in Adelaide,
South Australia. ALSA’s major objectives were to assess the
effects of social, biomedical, behavioural, economic, and
environmental factors upon age related changes in the health
and wellbeing of older persons.
The study has been
described in detail elsewhere.
28 29
The primary sample was
randomly selected from the South Australian electoral roll,
and stratified by local government area, sex, and age group
(70–74, 75–79, 80–84, and >85 years). Older men were over-
sampled to ensure sufficient numbers of men for longitudinal
follow up. Persons were eligible for the study if they were
resident in the Adelaide Statistical Division and aged 70 years
or more on 31 December 1992.
Seven waves of data have been collected to date. Interviews
with participants were held annually for the first four years
and then roughly every three years. The relevant ethics
committee approved the study, and each participant gave
written informed consent.
Of the original sample of 3263 persons, 2703 were eligible
for inclusion in the study and 1477 (55%) of these persons
agreed to participate. Those who refused were slightly older
and more likely to be female than the participants.
We used
data from the 1477 participants who completed a wave 1
interview. The retention of participants over the decade after
wave 1 interview in the study was excellent, with more than
75% of surviving participants interviewed at wave 6.
Social networks
Social networks with children, other relatives, friends, and
confidants were hypothesised as predictors of survival. The
derivation of these variables has been described
validated previously.
The children network combined
information on the number of children, proximity of
children, and frequency of personal and phone contact with
children. The relatives network was calculated from the
number of relatives (apart from spouse and children) the
participant felt close to, and the frequency of personal and
phone contact with these relatives. The friends network
captured the number of close friends, personal contact, and
phone contact. The confidant network reflected the existence
of confidants and whether the confidant was a spouse. A
total social network score was calculated as the sum of the
children, relatives, friends, and confidant network scores. All
component variables were standardised before the derivation
of the social network variables.
We included the social networks variables as either
continuous or categorical in subsequent analyses, dependent
on the analyses being undertaken.
Demographic, health, and lifestyle variables
To control for confounding in the analyses, the effects of
demographic, health, and lifestyle variables upon mortality
were also considered. These covariates were derived from self
reported wave 1 data. Demographic variables included age
group, sex, and geographical area of residence. Place of
residence was classified as community or residential care.
Current marital status was classified as married/partnered or
not married. Annual household income was coded as less
than or equal to $A12 000, more than $A12 000, or missing.
This cut off point for income was similar to the single
persons’ aged pension rate in 1992. The age at which the
participant left full time education was categorised as less
than or equal to 14 years of age or more than 14 years of age.
This cut off point for education was chosen as about half of
the sample left school aged 14 years of less; there was no
legal minimum school leaving age for this cohort. Other
analyses of ALSA data have used these education and income
cut off points (for example, Andrews et al
Physical and mental health status were also incorporated
in the analyses. Self rated health was classified as excellent/
very good, good, and fair/poor. The number of chronic
conditions was derived from self reported information on
whether each participant had ever suffered from 10 common
Disability was assessed via mobility.
cipants were defined as having no mobility disability if they
reported they were able to walk up and down a flight of stairs
and walk half a mile without help. If either or both of these
activities could not be completed, they were classified as
having a mobility disability.
Self reported hearing and visual
difficulty were also included. Depressive symptomatology
Table 1 Summary statistics for 1477 participants in wave 1 of ALSA
Characteristic Number* Overall (n = 1477) Survivors (n = 570) Decedents (n = 907)
Social networks mean (95%CI)
Children 1477 0.00 (20.04 to 0.04) 0.08 (0.01 to 0.14) 20.04 (20.10 to 0.01)
Relatives 1477 0.00 (2 0.04 to 0.04) 0.11 (0.04 to 0.17) 20.06 (20.11 to 20.01)
Friends 1477 0.01 (20.03 to 0.05) 0.19 (0.13 to 0.25) 20.11 (20.16 to 20.06)
Confidants 1477 0.01 (2 0.03 to 0.05) 0.10 (0.04 to 0.16) 20.04 (20.09 to 0.00)
Total 1477 0.02 (20.06 to 0.11) 0.48 (0.34 to 0.61) 20.26 (20.37 to 0.15)
Social networks tertile cut off points
Children 0th, 33Mrd, 66 Ord, 100th 1477 21.67, 20.02, 0.48, 1.17 21.67, 20.02, 0.49, 1.17 21.67, 20.11, 0.47, 1.17
Relatives 0th, 33Mrd, 66Ord, 100th 1477 21.05,20.53, 0.37, 2.02 21.05,20.33, 0.47, 2.02 21.05,20.53, 0.23, 2.02
Friends 0th, 33Mrd, 66Ord, 100th 1477 21.54, 20.33, 0.46, 1.19 21.54, 20.06, 0.61, 1.19 21.54, 20.42, 0.32, 1.19
Confidants 0th, 33Mrd, 66Ord, 100th 1477 21.68, 0.07, 0.09, 0.77 21.68, 0.09, 0.77, 0.77 21.68, 0.07, 0.09, 0.77
Total 0th, 33Mrd, 66Ord, 100th 25.69, 20.63, 0.84, 4.97 25.41, 20.08, 1.22, 4.63 25.69, 20.99, 0.51, 4.97
Age mean (95%CI) 1477 79.8 (79.4 to 80.1) 76.2 (75.8 to 76.7) 82.0 (81.6 to 82.4)
Sex male n (%) 1477 928 (62.8) 326 (57.2) 602 (66.4)
Place of residence community n (%) 1477 1340 (91.3) 554 (97.2) 786 (86.7)
Marital status married n (%) 1477 771 (52.2) 330 (57.9) 441 (48.6)
Age left school (14 years n (%) 1463 830 (56.7) 306 (53.8) 524 (58.6)
Household income ($12000 n (%)* 1369 590 (39.9) 212 (37.2) 378 (41.7)
Number of morbid conditions median
1477 1 (1 to 2) 1 (1 to 1) 1 (1–2)
Mobility disability 1455 506 (34.8) 113 (19.9) 393 (44.3)
Cognitive function poor n (%) 1440 219 (15.2) 36 (6.4) 183 (20.9)
Self rated health fair/poor n (%) 1472 469 (31.8) 116 (20.4) 353 (38.9)
Depressive symptoms n (%)* 1400 219 (14.8) 59 (10.4) 160 (18.6)
Hearing difficulty n (%) 1472 746 (50.7) 253 (44.4) 493 (54.7)
Vision difficulty n (%) 1410 375 (26.6) 92 (16.7) 283 (32.9)
Alcohol problem n (%) 1466 65 (4.4) 28 (4.9) 37 (4.1)
Current smoker n (%) 1461 123 (8.4) 31 (5.4) 92 (10.3)
Former smoker n (%) 1461 677 (46.3) 253 (44.5) 424 (47.5)
Pack years of smoking for current/former
smokers (median, 95%CI)
800 30.4 (27.7 to 32.4) 26.5 (21.5 to 30.4) 31.8 (29.2 to 35.4)
Sedentary n (%)* 1457 663 (45.5) 214 (37.6) 449 (50.6)
* Denominator in % is count of non-missing observations for each variable. If more than 74 (5%) observations were missing for a variable, then a category of
missing was added to ensure cases with missing observations were included in the analyses.
Social networks and 10 year survival in older Australians 575
was assessed using the 20 item CES-D scale,
32 33
with scores
of >17 out of a possible 60 suggesting symptoms of
depression. Cognitive function was measured using a subset
of items from the mini-mental state examination.
34 35
Health behaviours were also considered. Participants were
classed as current, former, or never smokers based on their
responses to questions concerning smoking. Participants
were classified as having a hazardous drinking problem if
their score on the 10 item AUDIT scale was eight or more.
Participants were classified as exercisers or sedentary based
on questions about the exercise undertaken in the previous
Statistical analyses and data linkage
Survival status was ascertained by searches of official death
certificates conducted by the Epidemiology Branch of the
Department of Health in South Australia, and deaths were
confirmed by the South Australian Births, Deaths and
Marriages bureau. Full name, date of birth, and last known
address of ALSA participants were used in the data linkage
with the deaths database. If no direct match was made, the
electoral roll was checked for errors in birth dates, changes or
errors in recorded name, and changes or errors in recorded
address. The few participants who died interstate or overseas
could not be identified through this method, as the deaths
database only includes deaths that occur in South Australia.
Informants nominated by ALSA participants at wave 1 were
contacted if participants could not be located at subsequent
interviews. The date of death supplied by informants was
used if a participant died outside of South Australia. These
methods of death ascertainment for ALSA participants have
been validated previously.
The response variable was the number of days to death
from wave 1 interview for decedents and 3653 days for
participants who survived 10 years after their initial inter-
The cumulative hazard of death over time was compared
graphically for the centile based classification of each social
network type using the Nelson-Aalen cumulative hazard
38 39
Broadly, a higher cumulative hazard curve
indicates a greater risk over time.
For each type of social network, a separate Cox propor-
tional hazards model was fitted to the data,
controlling for
the demographic, health, and lifestyle covariates. The Efron
method was used to correct for ties in the time to death.
The existence of threshold effects was investigated within
the framework of the proportional hazards model. For each of
the social network variables, we considered separately
thresholds corresponding to the tertiles. For example, to test
for a threshold at the 33Mrd centile, a dummy variable
showing whether the social network observation lay above
this centile point was included in the proportional hazards
model along with the original continuous variable. A
significant dummy variable indicated a threshold effect.
Backward elimination was used to remove non-significant
covariates from the regression equations. The fit of models
was assessed using graphical methods based on martingale
42 43
The assumption of proportional hazards was
assessed by regressing the scaled Schoenfeld residuals
against the log of time and testing for zero slope. A non-
zero slope provided evidence against proportional hazards.
Stata version 8.0 was used in all analyses (Stata Corporation,
College Station, TX).
Table 1 shows the characteristics of the 1477 participants at
wave 1 of ALSA. At the 10th anniversary of the wave 1
interview, 570 participants (326 male; 57%) were alive and
the remaining 907 participants (602 male; 66%) had died.
The mean specific and total network scores were higher for
the participants who survived 10 years after the wave 1
interview than for the participants who died in the
intervening decade. Tables detailing the relation between
each type of social network and the covariates are available
from the first author upon request.
Age group, sex, local government area, place of residence,
number of morbid conditions, cognitive function, self rated
health, and smoking status were significant predictors of
survival when the effects of the other covariates were
considered, and all subsequent analyses adjusted for these
variables. Table 2 presents the hazard ratios associated with
these variables. Non-proportional hazards were evident for
Table 2 Adjusted hazard ratios for effect of covariates on 10 year survival*
Variable HR 95% CI p Value
Sex, female 0.62 0.52 to 0.73 ,0.001
Age group 75–79 1.67 1.32 to 2.11 ,0.001
Age group 80–84 2.65 2.12 to 3.33 ,0.001
Age group 85+ 4.23 3.37 to 5.30 ,0.001
Dwelling residential aged care 1.36 1.09 to 1.71 0.008
Number of morbid conditions 1.09 1.03 to 1.16 0.006
Cognitive impairment yes 1.65 1.38 to 1.98 ,0.001
Self rated health good 1.26 1.06 to 1.50 0.009
Self rated health fair/poor 1.49 1.24 to 1.78 ,0.001
Smoking status former 1.14 0.97 to 1.34 0.117
Smoking status current 2.00 1.56 to 2.56 ,0.001
*Local government area (with 24 levels) not shown. Referent categories for adjusted hazard ratios are sex male,
age group 70–74, dwelling community, cognitive impairment no, self rated health excellent/very good, smoking
status never. Hazard ratios adjusted for other covariates.
HR (95% CI)
(p = 0.640)
(p = 0.990)
(p = 0.015)
(p = 0.077)
(p = 0.033)
Figure 1 Summary of adjusted hazard ratios (HR) and 95% confidence
intervals (95%CI) from Cox proportional hazards models for specific and
total social networks.
576 Giles, Glonek, Luszcz, et al
mobility disability, and therefore all analyses were stratified
by disability status.
The continuous social network variables were fitted and
the results are summarised in figure 1. Plots of martingale
residuals against the respective social network variables
confirmed that a linear functional form was appropriate for
these variables. There was a significant protective effect of
larger friends and total social networks against mortality. The
effect of networks with confidants was marginally signifi-
cant, and again showed a protective effect. The effects of
social networks with children and relatives were not
The existence of a threshold effect of social networks was
investigated using the dummy variables corresponding to the
tertiles, and were not significant in any analyses.
The hazard ratios corresponding to the tertile groupings are
shown in table 3 for friends, confidant, and total social
networks. The table shows a gradient in terms of the social
network variables. The effect of the friends network on
survival was greatest for those with the greatest networks of
friends (that is, in the upper tertile of the friends network
distribution). The effect of the confidant network was
beneficial to survival for those in both the middle and upper
tertiles of confidant networks.
Figure 2 shows the observed Nelson-Aalen cumulative
hazard estimates in days from the wave 1 interview for
friends and confidant networks and total social networks. In
each case, the groups defined by stronger networks have a
lower cumulative hazard and hence a lower risk of mortality
over time.
This study builds on previous work concerning social
relationships and mortality. Most other studies have used
ad hoc measures of social networks. Furthermore, there is a
paucity of research that has examined the effects of specific
social networks upon mortality. Through the use of objective
measures of specific social networks, developed originally for
a US sample and validated in ALSA, we have shown that
greater social networks with friends and confidants had
significant protective effects against mortality over a 10 year
follow up period. Networks with children and relatives were
not significant predictors of mortality over the same follow
up period. This highlights the importance of disaggregating
Table 3 Summary of adjusted hazard ratios for categorised social network variables
Network Tertile* HR 95% CI p Value
Friends 0–33Mrd 1.00
33M–66Ord 0.87 0.73 to 1.02 0.093
66O–100th 0.78 0.65 to 0.92 0.004
Confidants 0–33Mrd 1.00
33M–66Ord 0.85 0.72 to 1.00 0.049
66O–100th 0.83 0.70 to 1.00 0.044
Total 0–33Mrd 1.00
33M–66Ord 0.91 0.77 to 1.07 0.250
66O–100th 0.86 0.72 to 1.03 0.098
* Friends 0th, 33Mrd, 66Ord, 100th centile cut off points: 21.54, 20.33, 0.46, 1.19. Confidants 0th, 33Mrd,
66Ord, 100th centile cut off points: 21.68, 0.07, 0.09, 0.77. Total 0th, 33Mrd, 66Ord, 100th centile cut off
points: 25.69, 20.63, 0.84, 4.97. Hazard ratio adjusted for significant covariates.
Time (days)
0 300020001000
Time (days)
Nelson-Aalen cumulative hazard
Nelson-Aalen cumulative hazard
Nelson-Aalen cumulative hazard
0 300020001000
Time (days)
Lower tertile
0 300020001000
Mid tertile
Upper tertile
Figure 2 Nelson-Aalen cumulative
hazard estimates by type of social
Social networks and 10 year survival in older Australians 577
kin and non-kin networks, rather than relying on measures
of total social networks.
The finding that total social networks are protective against
mortality suggests overall social integration is important, and
reinforces findings from other studies of older people.
Previous Australian studies
have not shown an effect of
social networks on mortality. However, these studies were
generally smaller or did not consider the specific types of
social networks that were investigated in this study.
Differences in the definitions of social relationships and
different analyses may have contributed to the disparities in
previous reports.
Earlier research has shown social relationships with close
friends and/or relatives were protective against mortality in
older adults,
and subsequent research
also pointed to the
importance of a confidant in the perceived adequacy of social
support. By differentiating between friends, children, and
other relatives, we were able to show that it is friends, rather
than children or relatives, which confer most benefit to
survival in later life. Our finding of a marginally significant
effect of confidants upon survival suggests that discretionary
relationships, with friends and confidants, as compared with
relationships where there is less choice concerning interac-
tion, with children and relatives, have important positive
effects on survival. This is consistent with the socioemotional
selectivity theory proposed by Carstensen and colleagues,
showing that with age, one’s social choices may become more
selective as a means of regulating emotions.
The results from this study raise important questions about
how social networks with friends in particular impact upon
mortality. The causal relationship between social networks
and health is not well understood.
A recent review
proposed culture, socioeconomic factors, politics, and social
change condition the extent, shape, and nature of social
networks. In turn, social networks provide opportunities for
‘‘psychosocial mechanisms’’ that include social support,
social influence, social engagement, interpersonal contact,
and access to financial and health care resources.
Psychosocial mechanisms may have an impact upon health
through behavioural, psychological, and physiological path-
If we consider social networks within this framework,
networks with friends may exert an influence upon health
behaviours such as smoking, alcohol consumption, and
exercise, variables that were controlled for in our analyses.
Friends possibly also encourage health seeking behaviour,
which in turn can affect survival. Friends can have effects on
depression, self efficacy, self esteem,
coping and morale,
a sense of personal control,
possibly through social
engagement by reinforcing social roles
or because interac-
tions with friends stem from choice
or selectivity.
The effects of specific social networks upon mortality in
our study were of a similar magnitude to those we have seen
for self rated health and number of morbid conditions.
Furthermore, social network variables exerted an effect on
mortality 10 years after they were measured. For the effects
to be sustained over this long period suggests social networks
are powerful factors in protecting against premature death.
These baseline effects persisted even though many other
changes may have occurred for participants in the decade
after the wave 1 interview, including widowhood, deaths of
friends, siblings, children, or geographical relocation of some
members of their overall social network. Future work is
planned to assess changes in social networks among ALSA
participants, and the impact of any changes upon mortality.
The findings from this study must be interpreted with
several caveats. A wide range of covariates were included in
the analyses, but complete data were unavailable for some
potentially important factors, such as diet. However, given
that diet contributes to overall health, our covariates
indirectly capture this potential effect. ALSA was not
explicitly designed to examine the effects of social networks
on mortality, and the analyses are based on self reported data
and adjust for covariates measured at baseline. However,
these same limitations are true of most studies that have
considered social relationships and mortality in older adults.
The non-respondents to ALSA may have been more socially
isolated than participants, although non-response bias has
generally been shown as minimal in other analyses of ALSA
29 53 54
We believe these restrictions are balanced by
ALSA’s strengths, which include the richness of the baseline
data, the Australian setting, and the inclusion of residents in
aged care facilities. ALSA included a more heterogeneous
population sample than many other longitudinal studies of
In summary, we have shown that better social networks
with friends and confidants predict survival over the
following decade in a large cohort of older Australian men
and women. Strong social networks of discretionary relation-
ships may be important in ensuring longer survival.
We thank the participants in the Australian longitudinal study of
aging, who have given their time over many years, and without
whom this study would not have been possible. Sabine Schreiber of
the Centre for Ageing Studies, Flinders University, and the
Epidemiology Branch of the Department of Health in South
Australia are also thanked for their assistance with tracing
participants and identifying deaths.
Authors’ affiliations
L C Giles, Department of Rehabilitation and Aged Care, Flinders
University, Adelaide, Australia
G F V Glonek, Department of Applied Mathematics, University of
Adelaide, Adelaide, Australia
M A Luszcz, School of Psychology and Centre for Ageing Studies,
Flinders University
G R Andrews, Centre for Ageing Studies, Flinders University
Funding: this study was supported in part by grants from the South
Australian Health Commission, the Australian Rotary Health Research
Fund, and the US National Institute on Aging (grant no AG 08523-02).
Competing interests: none declared.
Ethics approval: ethics approval for the study was granted by the
Committee on Clinical Investigation, Flinders Medical Centre, South
Key points
Better social networks with friends and confidants
predict survival over the following decade in older
No effect of social networks with children or relatives
upon survival was found.
We did not find a threshold effect of specific social
relationships upon survival.
Policy implications
Strong social networks of discretionary relationships are
important in ensuring longer survival. Strategies to promote
the establishment and maintenance of such relationships in
later life deserve further attention.
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Social networks and 10 year survival in older Australians 579
... However, strategies for providing effective support are lacking [15,44]. Previous studies have suggested that social interactions are protective against mortality [15,20,45], and there is a need to rethink the way we provide support for social isolation. ...
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This study aimed to investigate whether social isolation is associated with mortality, together with the effect of the Great East Japan Earthquake on mortality, due to the social isolation of community residents living in the affected areas, using data from the Tohoku Medical Megabank Project Community-Based Cohort Study. A total of 22,933 participants (8059 men and 14,874 women), who were free from cancer and cardiovascular disease, were followed up with death as an endpoint for five years. Social isolation was assessed using the Lubben Social Network Scale (cut-off, 11/12). Using Cox proportional hazards models, hazard ratios (HRs) of total mortality and 95% confidence intervals (CIs) associated with social isolation (no isolation as the reference) were estimated. The latter was significantly associated with an increased risk of total mortality (1.38 (1.04–1.83) in men and 1.49 (1.02–2.19) in women). Moreover, among those with social isolation, the risk of mortality was significantly higher, especially for women with house damage and men who had experienced a death in the family. The disaster may have raised the risk of mortality due to social isolation.
... Friendship has repeatedly been shown to be an important type of social relationship. Friends contribute to success in coping with stress and anxiety (Winstead et al., 2016), individual well-being, general life satisfaction (Demir, 2015;Demir & Weitekamp, 2007;Lewis et al., 2015), and longevity (Giles et al., 2005) and may even have been key to survival during human evolution (Lewis et al., 2012). According to previous research, different types of friendships can be discerned: for instance, on the basis of closeness (e.g., general, close, or best friends), purpose (e.g., friends with benefits), or similarity (e.g., concerning sex, age, or personality). ...
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A key differentiation in studies on friendship research is between the same-sex and cross-sex friendships of women and men. Although most women and men prefer same-sex over cross-sex friends, most people do commonly have cross-sex friendships, and there are large interindividual differences in the proportions of cross-sex friends in individual friendship networks. Recent studies have suggested that same-sex and cross-sex friendships fulfill different goals for women and men. Therefore, individuals’ personal values (as representations of their enduring goals) may be associated with the types of friendships they prefer. The present study explores associations between personal values and people’s preferences for cross-sex friendships (heterosociality). A sample of 1,333 participants completed the assessment. Results showed that the associations were partially moderated by sex. For men, the value of tradition, whereas for women, the values of security, self-direction, and tradition were found to be significantly associated with the individual proportions of cross-sex friends. These findings contribute to understanding friendship selection and underline the importance of differentiating between same-sex and cross-sex friendships in women and men.
... A szerzők azt állítják, hogy a kapcsolathálózat távolabbi, periférikusabb kötései révén elérhető társas támogatás is hozzájárulhat az egészség és az általános jóllét megőrzéséhez (Kauppi et al. 2018). Egy ausztrál longitudinális kutatás azt is bizonyította, hogy az idős emberek jóllétéhez az erős/szoros kapcsolatok közül a barátokkal való interakciók nagyobb mértékben járulnak hozzá, mint a rokoni interakciók (Giles et al. 2005). ...
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A koronavírus világjárvány súlyosan érintette a legidősebb korosztályt, bár a 2. hullám alatt az is kiderült, hogy a középkorúak is nagy arányban megbetegedtek. Magyarországon a 3. hullám gyengülésekor -a korlátozások feloldásának harmadik fázisában - a COVID-19 fertőzés miatt elhunytak 92,7%-a 60 éves vagy annál idősebb volt. Az elhunytak korösszetétele más országokban is ehhez nagyon hasonlóan alakult. Mivel a sérülékeny idősek egészsége a koronavírus okozta súlyosabb megbetegedéseknek erősen kiszolgáltatott, a járvány kitörésekor világszerte szigorú kormányzati korlátozásokat vezettek be a védelmük érdekében. Ez a társadalmi elszigeteltség azonban - a járványt követő bizonytalanság, életmódbeli változások és pénzügyi nehézségek mellett - komoly pszichés és érzelmi megterhelést okozhat. Ilyen helyzet(ek)ben kitüntetett szerepe van a megküzdést segítő, a személyes kapcsolatok hálózatán keresztül hozzáférhető társas támogatás minden formájának. A tanulmány egyfelől azt tárja fel, hogyan változott a járvány kitörése után az 50 év feletti korosztály mentális jólléte Magyarországon nemzetközi összehasonlításban, másfelől azt is vizsgálja, hogy a társadalmi kapcsolatok mintázatai hogyan függnek össze a mentális egészségi állapotváltozásokkal. Elemzésünkhöz a SHARE COVID-19 nemzetközi adatbázisát használtuk. Eredményeink alapján egyrészt adódik egy triviális következtetés: a kapcsolathiányos network növeli leginkább a depresszió, a szorongás, az alvászavar és a magányérzet súlyosbodását. Érdekes viszont, hogy az intenzív szűk körű kapcsolati hálóval rendelkezők csoportjában nagyobb volt a mentális tünetek romlásának kockázata a többféle kapcsolataktívakéhoz képest. Sőt, az elektronikus kapcsolattartás - telefon, Skype stb. - sem segített: kifejezetten magas volt ebben a körben a depresszió súlyosbodásának valószínűsége a kapcsolatintenzív csoportéhoz képest. További érdekes eredmény, hogy mind a családi kapcsolatok által dominált csoportban, mind a többféle kapcsolatot tartók között kisebb a mentális tünetek rosszabbodásának esélye, azaz a személyes kontaktus - akár családtagokkal, akár más ismerősökkel - valóban védelmet jelent.
... Pure manual analysis is unable to cope with the everincreasing volume of data, while pure automatic algorithms are unable to grasp the data's in-depth significance (Hrabowski & Suess, 2010). Traditionally, educational researchers have collected data about students' learning experiences using methods such as surveys, interviews, focus groups, and classroom activities (Campbell, Deblois & Oblinger, 2007), (Giles, Glonek, Luszcz & Andrews, 2005). Because these procedures are often time-consuming, they cannot be replicated or repeated frequently. ...
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Purpose: This paper presents a critical analysis of the current application of big data in higher education and how Learning Analytics (LA), and Educational Data Mining (EDM) are helping to shape learning in higher education institutions that have applied the concepts successfully. Design/Methodology/Approach: An extensive literature review of Learning Analytics, Educational Data Mining, Learning Management Systems, Informal Learning and Online Social Networks are presented to understand their usage and trends in higher education pedagogy taking advantage of 21st century educational technologies and platforms. The roles of and benefits of these technologies in teaching and learning are critically examined. Value/Originality: Imperatively, this study provides vital information for education stakeholders on the significance of establishing a teaching and learning agenda that takes advantage of today's educational relevant technologies to promote teaching and learning while also acknowledging the difficulties of 21st-century learning. Aside from the roles and benefits of these technologies, the review highlights major challenges and research needs apparent in the use and application of these technologies. It appears that there is lack of research understanding in the challenges and utilization of data effectively for learning analytics, despite the massive educational data generated by high institutions. Also due to the growing importance of LA, there appears to be a serious lack of academic research that explore the application and impact of LA in high institution, especially in the context of informal online social network learning. In addition, high institution managers seem not to understand the emerging trends of LA which could be useful in the running of higher education. Though LA is viewed as a complex and expensive technology that will culturally change the future of high institution, the question that comes to mind is whether the use of LA in relation to informal learning in online social network is really what is expected? A study to analyze and evaluate the elements that influence high usage of OSN is also needed in the African context. It is high time African Universities paid attention to the application and use of these technologies to create a simplified learning approach occasioned by the use of these technologies.
... There has been an increased risk of cognitive downfall among seniors with weak social ties, not participating in social activities (14). The study carried out by Giles et al. (15) reports that social networks with high number of members are protective against mortality. Faulkner (16) reveals that the number of falling among socially isolated seniors has increased. ...
Social participation has tremendous implications for the physical and mental health of older adults. A growing body of Canadian literature has examined social participation among older adults, including frequency of participation; gender, age, and regional differences in participation; and associations with self-perceived health, loneliness, and life dissatisfaction. The current study adds to this important body of research, using a large, nationally representative sample of adults 45–85 years of age (Canadian Longitudinal Study on Aging [CLSA] baseline data [ n = 51,338]), to examine nuanced characteristics associated with social participation (socio-demographics, social support, cognitive ability, mental health, physical conditions), frequency of participation, and the relationship between the aforementioned characteristics and frequency of participation. Findings indicated that compared with those who reported infrequent/no participation, more frequent participation was associated with greater social support, higher cognitive abilities, increased satisfaction with life, fewer depressive symptoms, reduced odds of self-reported mood and anxiety disorders, and fewer self-reported physical conditions. Findings highlight the importance of active social participation, and have important implications for the development and implementation of accessible community programs across Canada.
This paper explores the social connectedness experiences among older migrants from culturally and linguistically diverse (CALD) backgrounds in Australia. Data were collected via two rounds of semi-structured interviews and analysed using thematic and cluster analysis. Participants were 40 migrants aged 66-91 years, of German, Dutch, Romanian, Chinese, and Vietnamese origin. They identified a range of factors affecting their social connectedness experiences: personal preferences, individual efforts to connect with others, English language proficiency, driving ability, and length of residence. Data analysis also revealed four groupings of experience: the isolated, family, ethnic community, and multicultural cluster. These patterns of connectedness were experienced differently across the ethnic groups. The findings suggest the benefits of providing culture-specific social connection opportunities to help older migrants to stay socially connected.
Objective For older adults receiving long-term care (LTC) at home, little is known about the role of social function in the onset of adverse outcomes, such as death, institutionalization, and functional decline. We examined the association between social function and adverse outcome onset among community-dwelling older adults with mild care needs. Methods This two-year longitudinal study recruited non-institutionalized older adults, with mild care need levels, in 2003. Participants were followed regarding the onset of death, institutionalization, and functional decline, after two years. Social function was assessed using four items (friendships, emotional support, instrumental support, and intergenerational interactions) and scored from zero (low) to four (high). Multivariable logistic regression analysis estimated the odds ratios (ORs) and 95% confidence intervals (CIs) for the onset of adverse outcomes, composite of death, institutionalization, and functional decline. Results Ultimately, 281 older adults were analyzed. During the observation period, the onset of adverse outcomes was observed in 41.4% of the participants (death, 13.9%; institutionalization, 7.9%; functional decline, 19.5%). Higher social function was inversely associated with adverse outcome onset, even after adjusting for covariates including cognitive function (compared to zero point, ORs [95% CIs] were 0.85 [0.42–1.70] for one, 0.42 [0.19–0.94] for two, and 0.44 [0.20–0.99] for three or more; p = 0.018). Among the subitems, friendships were associated with lower adverse outcome onset. Conclusions Higher social functioning was associated with the low onset of adverse outcomes among older adults under LTC. Enhancing social functions, including friendships, may be crucial for prognosis in LTC.
COVID-19 has had significant negative consequences for well-being. As well as the primary effects of the virus itself, secondary effects have resulted from the social isolation caused by the lockdowns imposed to slow the spread of the virus. Recognising the toxic effects of isolation, researchers, practitioners and policy-makers are conscious of the need to mitigate the negative effects of social distancing. Drawing on insights from a large body of research on the Social Identity Approach to Health, we devised an online activity-GROUPS 2 CONNECT (G2C)-aimed at helping people to maintain social connectedness when face-to-face interaction was not possible. Across four studies (N = 1021), we found that after completing the G2C activity, participants reported an increase in perceived quality of social connection, perceived ability to stay connected and well-being, with results showing that for two of the three longitudinal studies these uplifts were stable over time, and for all studies, the uplifts remained consistently higher for those who reported completing their social connection goals. These findings provide initial evidence of the value of G2C as a tool to support social connection, thereby reducing the risk of social isolation.
Purpose Loneliness in adults increases with age. Although loneliness has been found to be associated with psychiatric disorders and dementia, no information is available on prevalence of loneliness in older psychiatric patients. The aims of this study were to examine prevalence of loneliness in older psychiatric outpatients, including gender differences and associations with psychiatric disorders and social isolation. Methods Cross-sectional study in an outpatient clinic for geriatric psychiatry between September 2013 and February 2018. Interviews were done in 181 patients. Results 80% of participants were lonely. Loneliness was associated with having contacts in less social network domains, in women but not in men. There were no associations with DSM-IV-TR-classifications. However, loneliness was associated with higher scores on questionnaires for depression and cognitive function. Intensity of treatment did not differ significantly between lonely and non-lonely participants. Conclusion Loneliness is highly prevalent in older psychiatric outpatients, with men and women equally affected. Loneliness should be assessed in all older psychiatric patients, especially when they show high scores on symptom checklists or have a restricted social network.
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A total of 1,054 Hong Kong Chinese subjects aged 70 years or over were recruited into a cohort study to investigate the relation between social support and health outcomes. More than 30 social, health, and behavioral charactenstics were recorded as baseline information when the study began in 1985. Mortality data were obtained dunng a 2-year follow-up. Logistic regression analyses were used to determine the roles of these variables in predicting mortality. The mortality patterns of Hong Kong and of the studied cohort closely resemble that of Western developed countnes with cancer, heart disease, and cerebrovascular diseases as the leading causes of death. Besides sex and place of residence (whether living in the community or in homes for the elderly), the independent predictors of mortality included five baseline variables: being single or widowed, limited ability in activities of daily living, smoking habit, low body mass index, and poor self-evaluated health status. Subjects with at least three of these predictors had a relative risk of 3.9 (95% confidence interval 2 4–6.2) compared with those with zero to two of these characteristics Am J Epidemiol 1991; 133: 907–21
Incomplete failure data consisting of times to failure on failed units and differing running times on unfailed units are called multiply censored. Data on units operating in the field, for example, are usually multiply censored. Presented in this paper is a method of plotting multiply censored data on hazard paper to obtain engineering information on the distribution of time to failure. Step-by-step instructions on how to plot and interpret data on hazard paper are given with the aid of examples based on real and simulated data. Hazard paper is presented here for the exponential, Weibull, normal, log normal, and extreme value distributions. The theory underlying hazard paper and plotting is presented in an appendix.
The authors investigated associations between social integration and all-cause and cause-specific mortality among French employees of Electricity of France-Gas of France. A total of 12,347 men aged 40-50 years in 1989 and 4,352 women aged 35-50 years in 1989 comprised the sample. In age-adjusted survival analyses for all causes of death, men who were least socially integrated were 4.42 times as likely to die during follow-up (1993-1999) as those with the highest level of integration (p Language: en
This study examined the relationship between social network interaction and total and cardiovascular mortality in 17,433 Swedish men and women between the ages of 29 and 74 during a 6 year follow-up period. The study group was interviewed concerning their social network interactions and a total score was formed which summarized the availability of social contact. A number of sociodemographic and health related background variables known to be associated with mortality risk were also considered. Mortality was examined by linking the interview material with the Swedish National Mortality Registry. In the 6-year follow-up period 841 deaths occurred. The crude relative risk of dying during this period was 3.7 (95% CL 3.2; 4.3) when the lower social network tertile was compared to the upper two tertiles. When controlling for potential confounding effects, only age had a major influence on the association between social network interaction and mortality (RR age-adjusted = 1.46, 95% CL 1.25; 1.72). Controlling for age and sex, age and educational level, age and employment status, age and immigrant status, age and smoking, age and exercise habits and age and chronic disease at interview left the relative risk virtually unchanged. Controlling simultaneously for age, smoking, exercise and chronic illness yielded a risk estimate of 1.36 (95% CL 1.06; 1.69). Similar results were obtained when separately analyzing for cardiovascular disease mortality in an identical manner.
Half Title Title Copyright Dedication Preface Contents
Introduction.- Estimating the Survival and Hazard Functions.- The Cox Model.- Residuals.- Functional Form.- Testing Proportional Hazards.- Influence.- Multiple Events per Subject.- Frailty Models.- Expected Survival.
D.R. Cox has suggested a simple method for the regression analysis of censored data. We carry out an information calculation which shows that Cox's method has full asymptotic efficiency under conditions which are likely to be satisfied in many realistic situations. The connection of Cox's method with the Kaplan-Meier estimator of a survival curve is made explicit.
The CES-D scale is a short self-report scale designed to measure depressive symptomatology in the general population. The items of the scale are symptoms associated with depression which have been used in previously validated longer scales. The new scale was tested in household interview surveys and in psychiatric settings. It was found to have very high internal consistency and adequate test- retest repeatability. Validity was established by pat terns of correlations with other self-report measures, by correlations with clinical ratings of depression, and by relationships with other variables which support its construct validity. Reliability, validity, and factor structure were similar across a wide variety of demographic characteristics in the general population samples tested. The scale should be a useful tool for epidemiologic studies of de pression.