Research involving the D’Or Institute for Research and Education (IDOR) shows that the search for biomarkers still faces obstacles and may transform psychiatry in the future 

A study published in the journal Neuroscience and Biobehavioral Reviews, conducted by the University of Campinas (Unicamp) and the D’Or Institute for Research and Education (IDOR), shows that there is still no laboratory exam capable of diagnosing schizophrenia, despite important advances in the field. Currently, diagnosis is based on clinical interviews and observation of symptoms, with no biochemical tests or imaging exams available to support this process. 

The complexity of schizophrenia
Schizophrenia is a severe mental disorder that affects about 21 million people worldwide. Its most common symptoms include delusions, hallucinations, disorganized speech, behavioral changes, and cognitive difficulties that impact social and professional life. Unlike other areas of medicine, where laboratory tests help confirm diagnoses, psychiatry still relies on clinical criteria and subjective evaluations. 

This scenario has led scientists to search for biomarkers, meaning measurable biological indicators that could signal the presence, risk, or progression of psychiatric disorders. 

What the scientific review found
The study analyzed 49 investigations of proteins related to schizophrenia in body fluids such as blood and cerebrospinal fluid. These proteins were grouped into five main categories: diagnosis, prognosis, risk for psychosis, treatment response, and medication side effects. 

Some promising molecules emerged, such as brain-derived neurotrophic factor (BDNF), which is responsible for maintaining and supporting neuron survival; myelin basic protein (MBP), associated with the conduction of nerve impulses; and insulin-like growth factor (IGF), involved in the development of various tissues and metabolic processes. However, the results were highly heterogeneous, preventing any single biomarker from being clinically adopted. 

Another relevant point is that some proteins appear to be associated not only with schizophrenia, but with other psychiatric disorders as well. This supports the idea that the condition may not be a single entity, but rather a group of different conditions that share overlapping characteristics. 

Why there is still no reliable exam
According to the researchers, the difficulty in establishing biomarkers for schizophrenia is not due to a lack of strong studies, but to the instability of the current diagnostic framework itself. Because many patients receive different psychiatric diagnoses over the course of their lives, it becomes difficult to standardize results. In addition, the diversity of diagnostic criteria used internationally increases this variability even further. 

To move forward, experts argue for the need for longitudinal studies (which follow patients over time) and new ways of classifying mental disorders. Instead of viewing schizophrenia as a fixed disease, some scientists suggest understanding psychosis as a clinical state, which could open the door to identifying more consistent biological markers. 

Paths for the future of psychiatry
The review concludes that there is still no validated biomarker for diagnosing schizophrenia. However, it highlights proteomics (the field that studies the full set of proteins in an organism) as a promising area. The use of advanced technologies, such as mass spectrometry, may help identify more precise molecular patterns in the future. 

Thus, even without definitive answers, the study conveys a message of hope: gaining a deeper understanding of the biological basis of schizophrenia may transform psychiatric diagnosis and treatment, making them more objective, personalized, and effective.