Pseudobulbar Affect Correlates With Mood Symptoms in Parkinsonian Disorders but Not Amyotrophic Lateral Sclerosis

Abstract

Pseudobulbar affect (PBA) is a syndrome of affective disturbance associated with inappropriate laughter and crying, independent of mood. PBA is common in amyotrophic lateral sclerosis (ALS) and increasingly recognized in Parkinson's disease (PD) and atypical parkinsonism (aP). Correlates of PBA have not been systematically studied. The purpose of this study was to determine whether cognitive and psychiatric comorbidities correlated with patient-reported symptoms of PBA by using the Center for Neurological Study-Lability Scale among patients with ALS, PD, and aP. A total of 108 patients (PD, N=53; aP, N=29; ALS, N=26) completed a cognitive screener and self-reported measures of lability, depression, anxiety, apathy, and quality of life. Statistical analyses included one- and two-way analyses of covariance to evaluate group differences, Pearson's correlations to determine relationships between PBA symptoms and comorbidities, multiple regression for predicting PBA symptom severity in clinical correlates, and chi-square t tests for predicting demographic variables. PBA symptom severity did not vary between the three groups. Younger age and worse anxiety correlated with PBA symptom severity in all three groups, whereas depression and poor mental health/quality of life only correlated with PBA symptom severity in the PD and aP groups. PD and aP patients may be more likely to benefit from treatment with antidepressants. Increased PBA symptoms were associated with declines in cognitive functioning in the aP group, but sufficient numbers of PD and ALS patients with cognitive dysfunction may not have been recruited. The results suggest the possibility of an alternate pathophysiologic mechanism for PBA, which may vary between neurological disorders and disease progression. Mood and cognition are of particular relevance and should be evaluated when symptoms of PBA are suspected.

Pseudobulbar Affect in Parkinsonian Disorders: A Review

“…In fact, one study found that using a CNS-LS cutoff score of greater than or equal to 11 for detecting the presence of PBA symptoms in PD patients only provided a specificity of 51% for diagnosing PBA [25]. In addition to uncertainty regarding the validity of the CNS-LS in parkinsonian disorders, there is also a lack of agreement regarding the appropriate cutoff score to define PBA symptoms, with different studies using cutoff scores ranging from 11 to 21 [1,25,28,29].…”

“…While PBA tends to be less prevalent in movement disorders as compared to conditions such as ALS and TBI, it remains a disabling condition in many patients with parkinsonian disorders. PBA prevalence rates in patients with PD have been shown to range from 3.6% to 43%, and this high variability is in part secondary to differences in indexing measures and thresholds used (Table 1) [1,7,20,25,28,29,31]. Furthermore, some studies have found that PBA prevalence increases with disease progression [20,31]; between-study differences in disease severity may therefore contribute to between-study variability in PBA prevalence.…”

“…None of the 9 patients in this study with aP, which included patients with PSP, CBD, MSA, DLB, and vascular parkinsonism, were found to have PBA. In contrast, another study found the prevalence of PBA in their cohort of patients with aP to be nearly double that seen in their PD population (37.9% vs. 20.8%) [28]. A retrospective chart review of patients with MSA-C ( n = 28) found that 35.7% experienced PBA, with 50% exhibiting pathological crying and 50% exhibiting both laughter and crying [5].…”

“…A number of demographic and clinical characteristics have been correlated with the increased prevalence and/or severity of PBA symptoms in patients with parkinsonian disorders. PD patients with more advanced disease have been demonstrated to exhibit an increased prevalence of PBA [20,31], while younger PD patients have been shown to exhibit greater PBA symptom severity [28]. These factors need to be accounted for when examining PBA prevalence given that they may contribute to between-study variability.…”

“…Another study including 719 patients with movement disorders, including 387 PD patients, similarly found significantly higher depression scores in patients with PBA, and a trend towards impaired social well-being in PD patients with PBA [20]. Another study found that greater PBA symptom severity correlated with greater anxiety, greater depression, and reduced overall QoL in PD patients [28]. PBA has also been associated with changes in living status, i.e., being moved to supervised living and to reduced caregiver work productivity [9].…”