PRISM Registry: A Novel Tool to Prospectively Estimate the Prevalence of Pseudobulbar Affect Symptoms

Background/Objectives: Pseudobulbar affect (PBA) is an under-recognized and undertreated neurological disorder of emotional expression occurring secondary to a variety of neurological disorders. PBA is characterized by frequent, involuntary outbursts of crying and/or laughing and estimated to affect 1.5-2 million people in the USA. The PBA Registry Series (PRISM) was initiated in 2011 to prospectively estimate the prevalence of PBA symptoms among patients with six neurological conditions. Methods: Following Institutional Review Board approval, investigators are asked to enroll at least 20 patients with Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), Parkinson’s disease (PD), stroke, or traumatic brain injury (TBI). Participants (or caregivers) complete the Center for Neurologic Study–Lability Scale (CNS-LS) and a quality of life (QOL) measure. Demographics and psychotropic medication use are recorded. Results: As of June 2012, 4349 patients have enrolled. Of these, 36.6% had PBA symptoms defined by CNS-LS≥13; 9.2% had PBA symptoms using a more conservative threshold of CNS-LS≥21 (AD 30.1%/6.6%, ALS 46.3%/26.8%, MS 45.3%/11.2%, Stroke 36.1%/9.0%, PD 25.4%/5.5%, TBI 52.9%/16.8%). Patients with CNS-LS≥13 reported greater impact of their neurological condition on QOL than patients with CNS-LS<13 (6.7/4.6; 0-10 point scale; P<0.0001, two-sample t-test) and greater use of antidepressants (SSRIs 39.7%/27.2%, P<0.0001; TCAs 20.0%/10.1% P<0.0001) or antipsychotics (5.3%/2.9%; P<0.0001, Chi-square). Higher CNS-LS was associated with greater QOL impact (Pearson correlation 0.347). Conclusions: Prevalence estimates of PBA symptoms across associated neurological conditions are comparable to similarly conducted literature estimates. Presence of PBA symptoms appears to be associated with worse QOL and higher psychotropic use.