Review Article Integrated Models of Care for Medical Inpatients With Psychiatric Disorders: A Systematic Review Maria Hussain, M.D., FRCPC, Dallas Seitz, M.D., FRCPC Objective: Psychiatric disorders are common among medical inpatient settings and management of psychi- atric disorders can be challenging in this setting. Integrated models of care (IMCs) combining psychi- atric and medical specialties within a single service may improve psychiatric and medical outcomes, although evidence for IMCs in medical inpatient settings has not been well described. Method: We searched MEDLINE, Embase, and Google scholar for relevant articles. We included all randomized controlled trials or quasi- experimental studies in English that evaluated IMCs for medical inpatients with psychiatric disorders when compared with usual care. We defined IMCs as models of care where psychiatric and medical providers had joint responsibility for all patients within a given service. We extracted information on the characteristics of IMCs and on the effects of IMCs on psychiatric, medical, and health service outcomes. Results: Four studies met the inclusion criteria, thereby including 716 participants overall. All studies differed in the study design, models of IMCs, and outcomes reported. In 2 studies, IMCs improved psychiatric symptoms compared with those admitted to a general medical service. Two studies demonstrated reductions in length of stay with IMCs compared with usual care. One study reported an improvement in functional outcomes and a decreased likelihood of long-term care admission associated with IMCs when compared with usual care. Conclusions: There is preliminary evidence that IMCs may improve a number of outcomes for medical inpatients with psy- chiatric disorders. Additional well-designed studies of IMCs are required to further evaluate the effect of IMCs on patient outcomes and costs of care. (Psychosomatics 2014; ]:]]]–]]]) INTRODUCTION Medical conditions are common among adults with psychiatric disorders, which places the individuals at risk of medical complications due to poor health behaviors and inadequate preventative health care. The prevalence of psychiatric disorders in general medical inpatient settings has been estimated to be between 20% and 40%, 1–5 with certain medical con- ditions placing patients at higher risk. Up to 50% of patients with coronary artery disease have depressive symptoms, 6 and 42% of hospitalized patients with cancer are affected with major depression. 7 Data from older adults in medical settings demonstrate that the burden of psychiatric illness in this population is even higher, with up to 60% of hospitalized patients aged 65 years and older diagnosed with dementia, delirium, or depression. 8 Psychiatric disorders significantly increase both length of stay (LOS) and postdischarge health services utilization. Studies show that psychi- atric disorders are often unrecognized by non–mental health physicians. 9 Received July 25, 2013; revised July 25, 2013; accepted August 5, 2013. From Department of Psychiatry, Queen's University, Kingston, Ontario, Canada. Send correspondence and reprint requests to Maria Hussain, M.D., Kingston Geriatric Psychiatry Outreach Team, 640 Cataraqui Woods Drive, Unit 2, Kingston, Ontario, Canada K7P 2Y5; e-mail: hussainm@kgh.kari.net & 2014 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved. Psychosomatics 2014:]:]]]–]]] & 2014 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved. Psychosomatics ]:], ] 2014 www.psychosomaticsjournal.org 1