Transcript:
The clinical presentation of schizophrenia can include positive symptoms, negative symptoms, or both positive and negative symptoms. Most notably, hallucinations and delusions refer to excesses or distortions of perception and belief. Negative symptoms refer to deficits or reductions in normal, emotional, and/or functional capacities. Schizophrenia is most often recognized based on positive symptoms, whereas the negative symptoms may be less familiar to clinicians and therefore harder to detect.
In this video, we will review negative symptoms and the importance of accurately diagnosing them. Negative symptoms are present in nearly all patients with schizophrenia and include blunted affect, alogia, a reduction in verbal output or fluency of speech, anhedonia, avolition, and asociality. Negative symptoms usually appear before positive symptoms, often during the prodromal state, and can be severe and debilitating by the time an acute episode with positive symptoms occurs. In fact, negative symptoms such as anhedonia, a sociality, and avolition may cause greater disability and impairment of quality of life than do positive symptoms.
Negative symptoms of schizophrenia fall into 2 broad categories, primary negative symptoms and secondary negative symptoms. Primary negative symptoms are core aspects of schizophrenia. This is the category of negative symptoms that typically manifests before the positive symptoms and are present throughout the course of the disease. Primary negative symptoms of schizophrenia are particularly hard to recognize precisely because they often present before the positive symptoms that raise suspicion of schizophrenia in the first place.
As a result, anhedonia may be misinterpreted as lack of interest or engagement rather than a symptom of schizophrenia. A flat affect might be attributed to a person being emotionally distant. Avolition can be mistaken for any attribute that appears as a lack of motivation, even laziness. Asociality can be difficult to distinguish from natural introversion or social anxiety. Secondary negative symptoms emerge after the initial onset of schizophrenia and are not core features of the disease.
These symptoms may be caused by any number of factors, including comorbid mental illnesses such as depression, which is present in about 40% of patients with schizophrenia. Side effects of antipsychotics, which blunt effects of dopamine in the brain's reward center, substance use, and the burden of having schizophrenia. For example, social isolation during hospitalizations for acute episodes may contribute to ongoing asociality. Negative symptoms may even be caused by positive symptoms. This would be the case in delusional suspicion of others. A positive symptom led to social withdrawal, a secondary negative symptom. Rapid identification of secondary negative symptoms requires monitoring at frequent regular office visits with consideration of all potential causative factors. Several screening tools are available to assess negative symptoms of schizophrenia, including the Positive and Negative Syndrome Scale, or PANSS, the Scale for the Assessment of Negative Symptoms, or SANS, and the 16-item Negative Symptom Assessment, or NSA-16.
However, none of these scales differentiate between negative symptoms as primary or secondary, and their use may be limited by time constraints and the need for trained raters to administer them. The NSA-4, a condensed version of the NSA-16, is a short, easy-to-use instrument that evaluates 4 items, restricted speech quality, reduced emotion, reduced social drive, and reduced interest. The NSA-4 is convenient and easy to use in busy clinical settings. Nonetheless, even with these tools, diagnosing negative symptoms remains challenging. In addition to being harder to recognize, primary negative symptoms are more difficult to manage because they do not typically respond well to currently available antipsychotic therapies. This is not surprising, as the principal mechanism of antipsychotic agents is dopamine antagonism, which is effective against positive symptoms, but it can induce hypodopaminergic activity that may cause or aggravate negative symptoms. Secondary negative symptoms often improve when they're the root cause.
For example, comorbid depression, antipsychotic side effects, substance abuse, social isolation, or anhedonia, and even positive symptoms, are addressed with limited pharmacologic options. Treating negative symptoms generally focuses on nonpharmacologic interventions, including psychosocial interventions such as cognitive behavioral therapy or social skills training, supported employment or education, encouraging positive goals for living, learning, working and socializing, encouraging exercise and healthy lifestyle practices, and increased involvement of family and friends. For information on nonpharmacologic interventions for patients with schizophrenia, major depressive disorder, and bipolar disorder, the serious mental illness (SMI) advisor offers free evidence-based information on crisis services, patient and family engagement, peer support, psychiatric nursing, recovery support, social work, workplace issues, and much more. Given the challenges of recognizing negative symptoms of schizophrenia, let alone treating them, careful periodic assessment of patients with schizophrenia is of paramount importance. Moreover, because negative symptoms emerge before positive symptoms lead to a diagnosis of schizophrenia, the screening protocols to help identify patients at risk for schizophrenia or in the prodromal stages of the disease would be invaluable for ensuring prompt delivery of care.