Mortality in a Cohort of Homeless Adults in Philadelphia

BACKGROUND: Homeless people are at high risk for death from many causes, but age-adjusted death rates for well-defined homeless populations have not been determined. METHODS: We identified 6308 homeless persons 15 to 74 years of age who were served by one or both of two agencies for the homeless in Philadelphia between January 1, 1985, and December 31, 1988. Using a data base that contained all deaths in Philadelphia and listings of all Philadelphia residents during the same period, we compared the mortality rate for this homeless population with the rate in the general population of Philadelphia. RESULTS: The age-adjusted mortality rate among the homeless was 3.5 times that of Philadelphia's general population (95 percent confidence interval, 2.8 to 4.5). The age-adjusted number of years of potential life lost before the age of 75 years was 3.6 times higher for the homeless people than for the general population (345 vs. 97 years lost per 1000 person-years of observation). Fifty-one of the 96 deaths of homeless persons (53 percent) occurred during the summer months. Mortality rates were higher among the homeless than in the general population for nonwhites, whites, women, and men. Within the homeless cohort, white men and substance abusers had higher mortality rates than other subgroups, but even homeless people not known to be substance abusers had a threefold higher risk of death than members of the general population. Injuries, heart disease, liver disease, poisoning, and ill-defined conditions accounted for 73 percent of all the deaths among the homeless. CONCLUSIONS: Homeless adults in Philadelphia have an age-adjusted mortality rate nearly four times that of Philadelphia's general population. White men and substance abusers are at particularly high risk. Matching cohorts of homeless people to death records is a useful way to monitor mortality rates over time, evaluate interventions, and identify subgroups with an increased risk of death.