Negative Symptoms in Schizophrenia: A Review and Clinical Guide for Recognition, Assessment, and Treatment

Abstract

Schizophrenia is frequently a chronic and disabling disorder, characterized by heterogeneous positive and negative symptom constellations. The objective of this review was to provide information that may be useful for clinicians treating patients with negative symptoms of schizophrenia. Negative symptoms are a core component of schizophrenia that account for a large part of the long-term disability and poor functional outcomes in patients with the disorder. The term negative symptoms describes a lessening or absence of normal behaviors and functions related to motivation and interest, or verbal/emotional expression. The negative symptom domain consists of five key constructs: blunted affect, alogia (reduction in quantity of words spoken), avolition (reduced goal-directed activity due to decreased motivation), asociality, and anhedonia (reduced experience of pleasure). Negative symptoms are common in schizophrenia; up to 60% of patients may have prominent clinically relevant negative symptoms that require treatment. Negative symptoms can occur at any point in the course of illness, although they are reported as the most common first symptom of schizophrenia. Negative symptoms can be primary symptoms, which are intrinsic to the underlying pathophysiology of schizophrenia, or secondary symptoms that are related to psychiatric or medical comorbidities, adverse effects of treatment, or environmental factors. While secondary negative symptoms can improve as a consequence of treatment to improve symptoms in other domains (ie, positive symptoms, depressive symptoms or extrapyramidal symptoms), primary negative symptoms generally do not respond well to currently available antipsychotic treatment with dopamine D₂ antagonists or partial D₂ agonists. Since some patients may lack insight about the presence of negative symptoms, these are generally not the reason that patients seek clinical care, and clinicians should be especially vigilant for their presence. Negative symptoms clearly constitute an unmet medical need in schizophrenia, and new and effective treatments are urgently needed.

Keywords: clinical presentation; diagnosis; negative symptoms; prevalence; schizophrenia; treatment.

Figure 1

Actionable factors that cause or contribute to secondary negative symptoms. Notes: *Including Huntington’s disease, multiple sclerosis, Parkinson's disease, traumatic brain injury, chronic pain, sleep apnea, temporal lobe epilepsy.

Figure 2

Schematic course of negative symptoms in schizophrenia. Negative symptoms are present throughout the course of schizophrenia. They can occur early, persist over time, increase in severity, and remain between acute episodes of illness. Correll, C. The Prevalence of Negative Symptoms in Schizophrenia and Their Impact on Patient Functioning and Course of Illness. The Journal of Clinical Psychiatry. 74(2):e04, 2013. Copyright 2019, Physicians Postgraduate Press. Reprinted by permission.

Figure 3

Key negative symptom constructs. Blunted affect=decreased expression of emotion; alogia=reduction in quantity of words spoken; avolition=reduced initiation and persistence of goal-directed activity due to decreased motivation; asociality=reduced social interactions and initiative due to decreased interest in relationships with others; anhedonia=reduced experience of pleasure during an activity or in anticipation of an activity.

Figure 4

Clinical presentation of negative symptoms.