Social isolation, social activity and loneliness as survival indicators in old age; a nationwide survey with a 7-year follow-up

BackgroundSocial networks have been established as a powerful predictors of mortality. However, less is known in how its conceptual dimensions – social isolation, social activity and perceived loneliness are interrelated and to what extent they are independent risk indicators.ObjectiveTo investigate the value of social isolation, social inactivity and loneliness as survival predictors in old age.MethodA postal questionnaire responded by 3858 random older people (> 75 years) included detailed information on social contacts, social activities and loneliness. The vital status was followed for 7 years.ResultsSocial isolation (46.1%), social inactivity (39.4%), and suffering from loneliness (37.0%) represented population groups of almost equal size, while 23% of people were outside these groups. These groups only partly overlapped, and 8.7% were simultaneously socially isolated, socially inactive and lonely. The mortality rate was 29.9% in people, who were not lonely nor socially isolated nor inactive but 52.9% in the lonely, socially isolated and inactive. Both social inactivity and self-reported loneliness emerged as independent mortality risk indicators, whereas social isolation did not. The impact of social inactivity and self-reported loneliness was additive both in men and women and the survival curves diverged over time.ConclusionsSocial inactivity and self-reported loneliness and their combination, particularly, are significant risk indicators in a general aged population whereas social isolation is not.