Diagnostic Transitions from Primary Psychiatric Disorders to Underlying Medical Conditions: A 5-Year Retrospective Survey from a University Hospital Sample.

Background: Undiagnosed underlying medical conditions can cause many patients to be followed, for years, by a diagnosis of a primary psychiatric disorder and to receive inappropriate treatment. The aim of this study was to determine the prevalence of patients initially diagnosed with a primary psychiatric disorder but whose symptoms were later attributed to medical conditions. These patients' initial and final diagnoses were also examined. Methods: The records of 1843 patients hospitalized in Gazi University Faculty of Medicine Psychiatric Inpatient Clinic between 2015 and 2020 were examined in this retrospective and descriptive study. Thirteen patients were excluded from the study due to insufficient data. Descriptive statistics were performed on the data of 30 patients diagnosed with an underlying medical condition. Results: In follow-up, 49 patients' diagnoses changed. 19 patients had a diagnosis unrelated to an underlying medical condition, and 30 had a diagnosis related to an underlying medical condition. Five (16.7%) of the patients, previously known to have psychiatric disorders, were found to have Alzheimer's disease. Brain space-occupying lesions, frontotemporal dementia, epilepsy, Parkinson's disease, and Arnold-Chiari malformation followed Alzheimer's disease at 6.7% (n = 2). The mean time until the diagnosis of the patients was revised was 4.95 years (standard deviation [SD] = 7.78). It was observed that psychotropic medications (90%) were used more than non-psychotropic drugs until the diagnosis was revised. Conclusion: During the diagnostic process, we believe that clinicians should be aware of potential underlying medical conditions and that the multidisciplinary work of psychiatry and neurology is also crucial.