When specialization creates exclusion: the dangers of a compartmentalized medical system

Over the years, medical care has become increasingly specialized, with each discipline focusing on narrower areas of expertise. While this specialization has led to major advances and improved the quality of care, it has also resulted in the compartmentalization of healthcare. Patients with multiple conditions are often required to consult several specialists, and care is delivered in fragments rather than as a whole.

In a recent study, Professor Kiyoto Kasai from the International Research Center for Neurointelligence (WPI-IRCN), along with Dr. Yousuke Kumakura from the Department of Neuropsychiatry, Graduate School of Medicine, and Dr. Shin-ichiro Kumagaya from the Research Center for Advanced Science and Technology, all at The University of Tokyo, Japan, examined the severe consequences of this fragmentation by analyzing the collective experiences of multiple patients with a genetic disorder that causes a wide range of medical, developmental, and psychiatric conditions. This analysis draws on patients seen at the 22q11 deletion syndrome Special Clinic at the University of Tokyo Hospital, as well as participants from related surveys and interviews. The study reveals how compartmentalization led to a patient being refused care, details the debilitating effects on her life, and demonstrates how interdisciplinary care ultimately led to positive outcomes. Their findings are published in Volume 406, Issue 10,517 of the journal The Lanceton November 15, 2025.

“Medical compartmentalization occurs when clinicians become so entrenched in their specialty—with its own set of rules, rationality, and obligations—that they do not operate beyond their area of expertise. Our study reveals the ‘invisible mismatch’ that occurs when individuals with multiple, co-occurring disabilities, such as congenital heart disease, intellectual and developmental disabilities, and psychiatric symptoms, encounter medical systems that are organized into narrowly defined specialties,” says Prof. Kasai.

To illustrate this systemic failure, the researchers consolidated these patient experiences into a single representative case study named Cocoro, presented as a 22-year-old woman with chromosome 22q11.2 deletion syndrome. Her medical history includes a surgically repaired tetralogy of Fallot (a congenital heart defect), mild heart failure, skeletal malformations, autism spectrum disorder, and significant learning and sensory challenges. Despite her needs, she was placed in a regular school, where she faced persistent misunderstanding, bullying, and harassment by a teacher. The healthcare system proved similarly ill-equipped. Because of her medical complexity, particularly her congenital heart disease, multiple psychiatric and adult-care clinics refused to treat her, citing difficulties in managing conditions outside their specialty.

A pivotal change occurred when she was finally referred to a psychiatric department that practiced interdisciplinary care. There, a team of psychiatrists, psychologists, social workers, and a medical liaison conducted a comprehensive assessment and developed a coordinated care plan. With their help, Cocoro began attending a workshop for people with mental disabilities, where she formed supportive peer relationships. Her parents also found support by connecting with other families and later began offering peer support themselves. With this integrated approach, the family’s overall well-being improved, and Cocoro was able to re-engage with her hobbies.

Nevertheless, concerns remain about her access to future cardiac surgery in hospitals without psychiatric services and about the long-term sustainability of Cocoro’s care as her parents age. Her case highlights three main problems caused by compartmentalized care: care was split across medical specialties with no single team taking overall responsibility; her treatment became disjointed when she moved from children to adult health services; and the healthcare system focused only on her as a patient, while overlooking her caregivers.

To dismantle these barriers, the researchers propose three key systemic reforms. First, they call for changes in medical education to help clinicians recognize and address compartmentalization. Second, they emphasize ensuring continuity of care as patients transition from childhood to adulthood, particularly for those with complex, long-term conditions. Third, they call for wider changes to the healthcare system to remove structural obstacles, particularly for people with multiple long-term conditions who are most harmed by fragmented care.

This article is based on a press release from the International Research Center for Neurointelligence (WPI-IRCN), The University of Tokyo.