Does social isolation predict hospitalization and mortality among HIV+ and uninfected older veterans?
OBJECTIVE
To compare levels of social isolation in aging veterans with and without the human immunodeficiency virus (HIV) and determine associations with hospital admission and mortality.


METHODS
Longitudinal data analysis.


METHODS
The Veterans Aging Cohort Study (VACS), at eight VA Medical Centers nationally.


METHODS
Veterans aged 55 and older enrolled in VACS from 2002 to 2008 (N = 1,836).


METHODS
A Social Isolation Score (SIS) was created using baseline survey responses about relationship status; number of friends and family and frequency of visits; and involvement in volunteer work, religious or self-help groups, and other community activities. Scores were compared according to age and HIV status, and multivariable regression was used to assess effects of SIS on hospital admission and all-cause mortality.


RESULTS
Mean SIS was higher for HIV-positive (HIV+) individuals, with increasing difference according to age (P = .01 for trend). Social isolation was also more prevalent for HIV+ (59%) than uninfected participants (51%, P < .001). In multivariable regression analysis of HIV+ and uninfected groups combined, adjusted for demographic and clinical features, isolation was independently associated with greater risk of incident hospitalization (hazard rate (HR) = 1.25, 95% confidence interval (CI) = 1.09-1.42) and risk of all-cause mortality (HR=1.28, 95% CI = 1.06-1.54). Risk estimates calculated for HIV+ and uninfected groups separately were not significantly different.


CONCLUSIONS
Social isolation is associated with greater risk of hospitalization and death in HIV+ and uninfected older veterans. Despite similar effects in both groups, the population-level effect of social isolation may be greater in those who are HIV+ because of the higher prevalence of social isolation, particularly in the oldest individuals.
Divisions of Hospital Medicine, University of California at San Francisco, San Francisco, California.
S Ryan
SR
Greysen
Leora I
LI
Horwitz
Kenneth E
KE
Covinsky
Kirsha
K
Gordon
Michael E
ME
Ohl
Amy C
AC
Justice
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000401:mortality*; D006679:HIV Seropositivity / Q000401:mortality*; D006760:Hospitalization / Q000639:trends*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D012934:Social Isolation; D015996:Survival Rate / Q000639:trends; D014481:United States / Q000453:epidemiology; D014728:Veterans / Q000523:psychology / Q000706:statistics & numerical data*
HIV/AIDS; aging; hospitalization; mortality; outcomes of care; social isolation