Prevalence of Pseudobulbar Affect in Patients With Dementia

Elderly woman, wheelchair, old, patient
Elderly woman, wheelchair, old, patient
Symptoms of PBA were observed in nearly three-quarters of patients with dementia.

ATLANTA, Georgia – Pseudobulbar affect (PBA), also known as emotional lability, is a disinhibition syndrome characterized by sudden, unprovoked, and inappropriate outbursts of involuntary laughing or crying. This disorder of emotional expression affects an estimated 1.8 to 7.1 million individuals in the United States. Symptoms of PBA may occur in patients with varied neurologic diseases including amyotrophic lateral sclerosis, multiple sclerosis, Parkinson disease, and Alzheimer disease, and can coexist with psychiatric illness such as depression and anxiety.1

A team of clinicians affiliated with Brookdale University Hospital and Medical Center in Brooklyn, New York, screened 80 nursing home residents to determine the prevalence of PBA symptoms in patients diagnosed with dementia or HIV-dementia and to assess PBA comorbidity with depression in the same population. Screening for PBA was conducted using the previously validated Center for Neurologic Study – Lability Scale (CNS-LS) questionnaire.2,3 Milania Dela Cruz, MD, MPH, a resident in psychiatry, and colleagues hypothesized high prevalence of PBA symptoms and high depression comorbidity in patients diagnosed with HIV-dementia.

According to study findings presented at the 2016 Annual Meeting of the American Psychiatric Association (APA), in Atlanta, Georgia, symptoms of PBA were observed in nearly 45% and 70% of patients diagnosed with dementia or HIV-dementia, respectively.4 “Further studies are needed to corroborate the findings in patients with HIV-dementia, and more refined screening tools should be developed for patients who exhibit PBA symptoms”, the researchers noted in the study abstract.

When discussing potential limitations of the study, the researchers acknowledge small sample size, limited psychometric properties of the CNS-LS, recall bias (CNS-LS questionnaire is self-administered), and data (medications, Mini-Mental Status Exam, other diagnosis) obtained from medical records.

In 2010, the US Food and Drug Administration (FDA) approved dextromethorphan/quinidine for PBA based on findings of a large randomized, placebo-controlled clinical trial,5 and the authors of this study concede that this drug “might be effective in patients diagnosed with HIV-dementia who exhibit PBA symptoms.”

Click here for more research from the 2016 Annual Meeting of the American Psychiatric Association.


  1. Ahmed A, Simmons Z. Pseudobulbar affect: prevalence and management. Ther Clin Risk Manag. 2013;9:483-489.
  2. Moore SR, Gresham LS, Bromberg MB, Kasarkis EJ, Smith RA. A self report measure of affective lability. J Neurol Neurosurg Psychiatry. 1997;63:89-93.
  3. Smith RA, Berg JE, Pope LE, Callahan JD, Wynn D, Thisted RA. Validation of the CNS emotional lability scale for pseudobulbar affect (pathological laughing and crying) in multiple sclerosis patients. Mult Scler. 2004;10:679-685.
  4. Cruz MD, Predescu I, Ahmad M, Paramatmuni S, Springer C, Belzie L. Prevalence and correlates of pseudobulbar affect symptoms in urban setting nursing home residents with dementia. Poster presentation at: 2016 Annual Meeting of the American Psychiatric Association; May 14-18, 2016; Atlanta, GA. P2-039.
  5. Pioro EP, Brooks BR, Cummings J, et al. Dextromethorphan plus ultralow-dose quinidine reduces pseudobulbar affect. Ann Neurol. 2010; 68:693-702.