Anhedonia Highlighted as a Frequently Misunderstood Symptom in Psychiatric Conditions at 2024 NEI Fall Congress
“Anhedonia is a lot of things aside from the lack of feeling enjoyment,” said Andrew J. Cutler, MD, meeting chairman, as he introduced his session “Something to Anticipate: Improving the Lives of Patients With Anhedonia” at the 2024 Neuroscience Education Institute (NEI) Fall Congress in Colorado Springs, Colorado.
Anhedonia is a common feature of depression and other psychiatric conditions, like attention-deficit/hyperactivity disorder (ADHD), schizophrenia, dementia, substance use disorders, and more. Distinct from emotional blunting or apathy, patients experiencing anhedonia, “have a reduced ability to experience pleasure or interest in things previously enjoyable.”
Other major risk factors for anhedonia include early life abuse, post-traumatic stress disorder (PTSD), chronic stress, and inflammatory illnesses like COVID-19 (in fact, as Dr Cutler shared, anhedonia is a consistent feature of “long COVID” syndrome). Untreated anhedonia can lead to a host of negative outcomes, ranging from treatment-resistant depression to increased suicidality to increased risk for cardiovascular diseases to impairment of cognitive function.
In terms of the underlying neurobiology and neurocircuitry, anhedonia occurs when the reward processing circuits in the brain are dysfunctional, with specific pathways “often either hyperactivated or compromised in anhedonia.” Anhedonia interferes with many neurotransmitters, including dopamine, gamma-aminobutyric acid (GABA), glutamate, serotonin, and opioids.
Dr. Cutler emphasized to the audience the importance of looking at the whole brain circuit rather than focusing on specific hormones or neurotransmitters in isolation: “We’ve been trying to teach at NEI in recent years that it’s not just one symptom in one diagnosis, but it’s also about modulation. There’s not always too much or too little of something.”
“I want you to think of some of these things as transdiagnostic, as a circuit, one that cuts across multiple diagnoses aside from depression,” Dr. Cutler said. This explains why traditional approaches singularly administered, like selective serotonin reuptake inhibitors (SSRIs), rarely alleviate anhedonia, even if they induce overall improvement in depression and/or anxiety.
At this time, there is not a strong body of evidence for which medications may best improve anhedonia. However, many agents are under investigation, with the strongest empirical evidence so far supporting ketamine, agomelatine, vortioxetine, esketamine, and transcranial magnetic stimulation. There are also some evidence-supported nonpharmacological interventions that show promise for alleviating anhedonia, including cognitive behavioral therapy and exercise.
Reference
Cutler AJ. Something to anticipate: Improving the lives of patients with anhedonia. Presented at: NEI Fall Congress; November 7-10, 2024; Colorado Springs, Colorado.
