Involuntary Emotional Expression Disorder
Involuntary Emotional Expression Disorder, or IEED, is a condition in which a person experiences uncontrollable episodes of emotional expression. That is, they have episodes of crying, laughter, or anger that are not in line with their present mood.
The condition is also known as labile affect, pseudobulbar affect, emotional lability, and pathological laughing and crying. It can have a severe impact on the lives of both patients and caregivers, as symptoms may leave sufferers feeling guilty, awkward, embarrassed and reluctant to take part in social interaction.
IEED is seen most often following brain injury or in people with dementia, motor neuron disease, and multiple sclerosis. It can appear at any stage of the associated diseases.
Its prevalence was estimated in 2007 by Walter Bradley, MD, of Miami University. His team surveyed 2,318 patients, or their caregivers, with the neurological diseases or injuries previously linked to IEED. They used two reliable tools for diagnosis: the Pathological Laughing and Crying Scale and the Center for Neurological Study Lability Scale.
Overall, the rate of IEED was approximately ten percent, suggesting that the condition affects between 1.8 and 1.9 million patients with neurological disorders in the U.S. It was most common alongside amyotrophic lateral sclerosis, at 33 percent, and least common in those with Parkinson’s disease, at four percent.
IEED is underdiagnosed, said Bradley, as the symptoms mimic other clinical emotional disorders, including depression, bipolar disorder, schizophrenia, generalized anxiety disorder, and even epilepsy. Of the 59 percent of patients who told a physician about their symptoms, less than half received a diagnosis or treatment, and the diagnosis was most often depression.
Bradley said, “This is unfortunate because IEED seriously hampers social interactions and can have a significant deleterious effect on patients’ and their families’ quality of life.”
IEED is often missed by physicians because they assume the crying outbursts are a manifestation of depression, points out Peter Rabins, MD, of Johns Hopkins University School of Medicine in Baltimore. He adds that many patients are unable to describe their emotions due to dementia. “So, what you see is someone who suddenly cries intermittently. It is hard to know whether he is depressed, has IEED, or is having what is called a catastrophic reaction.”