Effect of social networks on 10 year survival in very old Australians: the Australian longitudinal study of aging
- 1Department of Rehabilitation and Aged Care, Flinders University, Adelaide, Australia
- 2Department of Applied Mathematics, University of Adelaide, Adelaide, Australia
- 3School of Psychology and Centre for Ageing Studies, Flinders University
- 4Centre for Ageing Studies, Flinders University
- Correspondence to: MsL C Giles Department of Rehabilitation and Aged Care, Flinders University, GPO Box 2100, Adelaide, South Australia 5001, Australia;
- Accepted 23 November 2004
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.
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 Australia.