Author Affiliations: Cardiovascular Division, Department of Medicine, Women's College Hospital, University of Toronto, Toronto, Ontario, Canada (Dr Udell); INSERM U-698, Universite Paris-Diderot, Sorbonne Paris Cite, and Department de Cardiologie, Hopital Bichat, Assistance Publique, Hopitaux de Paris, Paris, France (Dr Steg); and VA Boston Healthcare System, Brigham and Women's Hospital, and Harvard Medical School, Boston, Massachusetts (Dr Bhatt).
Simons et al suggest that social isolation is inconsistently associated with cardiovascular risk or survival. Although that may be the case, the association observed between living alone with cardiovascular risk and survival in the REduction of Atherothrombosis for Continued Health (REACH) data1 may be a result of a much larger sample size than previously studied, since some of the data from the study cited by Simons et al directionally support an association but may have been underpowered. In addition, there are several mechanisms by which living alone could be linked with adverse cardiovascular outcomes, some of which are potentially causative (eg, depression and mortality following myocardial infarction) and some of which are just associations.
Udell JA, Steg PG, Bhatt DL. Impact of Loneliness and Living Alone—Reply. JAMA Intern Med. 2013;173(4):322-323. doi:10.1001/jamainternmed.2013.2011