Objective
To examine the relationship between marital status, an important aspect of social support, and several hospital outcomes.

Methods
Patients included 40 820 adult medical and surgical patients discharged from a midwestern academic medical center during 1988 through 1991, of whom 21 291 were unmarried and 19 529 were married. Using multivariable regression analyses, we compared the following outcomes in married and unmarried patients: rate of in-hospital death, rate of nursing home discharge, length of stay, and hospital charges. Severity of illness was measured using a previously validated commercial method.

Results
Admission severity of illness was higher in unmarried than married patients; 40% of unmarried patients had moderate or high severity compared with 32% of married patients. In a series of multivariable analyses, controlling for severity of illness, age, gender, race, and diagnosis, the risk of nursing home discharge was more than 2.5 times greater for unmarried than for married patients (multivariable odds ratio, 2.67; 95% confidence interval, 2.33 to 3.06), while the risk of inhospital death for unmarried compared with married patients was higher among surgical patients (odds ratio, 1.30; 95% confidence interval, 1.06 to 1.58) but not among medical patients (odds ratio, 0.98; 95% confidence interval, 0.84 to 1.15). In additional analyses, multivariable models estimated that hospital charges and length of stay were 5% and 8% higher (P<.001), respectively, for unmarried than for married patients. In a series of stratified analyses, the above differences among unmarried patients tended to be greater for patients who were never married than for patients who were widowed, divorced, or separated.

Conclusions
The findings suggest that marital status was an independent risk factor for several important hospital outcomes. This adds to our understanding of the importance of social support and other nonbiological factors on outcomes in hospitalized patients. This also has implications for the design of hospital-based interventions to improve patient outcomes and for the development of equitable prospective and capitated hospital payment formulas.

(Arch Intern Med. 1995;155:2465-2471)