Objective: To examine the impact of an interdisciplinary, collaborative practice intervention involving a primary care physician, a nurse, and a social worker for community-dwelling seniors with chronic illnesses.Methods: A concurrent, controlled cohort study of 543 patients in 18 private office practices of primary care physicians was conducted. The intervention group received care from their primary care physician working with a registered nurse and a social worker, while the control group received care as usual from their primary care physician. The outcome measures included changes in number of hospital admissions, readmissions, office visits, emergency department visits, skilled nursing facility admissions, home care visits, and changes in patient selfrated physical, emotional, and social functioning.Results: From 1992 (baseline year) to 1993, the two groups did not differ in service use or in self-reported health status. From 1993 to 1994, the hospitalization rate of the control group increased from 0.34 to 0.52, while the rate in the intervention group stayed at baseline (P=.03). The proportion of intervention patients with readmissions decreased from 6% to 4%, while the rate in the control group increased from 4% to 9% (P = .03). In the intervention group, mean office visits to all physicians fell by 1.5 visits compared with a 0.5-visit increase for the control group (P = .003). The patients in the intervention group reported an increase in social activities compared with the control group's decrease (P=.04). With fewer hospital admissions, average per-patient savings for 1994 were estimated at $90, inclusive of the intervention's cost but exclusive of savings from fewer office visits.
Conclusions:This model of primary care collaborative practice shows potential for reducing utilization and maintaining health status for seniors with chronic illnesses. Future work should explore the specific benefit accruing from physician involvement in the collaborative practice team.
