Correlates of generalized anxiety and panic attacks in dystonia and Parkinson disease.

OBJECTIVE: To determine prevalences of generalized anxiety, generalized anxiety disorder, panic attacks, and panic disorder in primary dystonia (n = 28) and Parkinson disease (n = 28) and to explore their clinical correlates.
BACKGROUND: We previously identified increases in Diagnostic and Statistical Manual of Mental Disorders, third edition generalized anxiety in dystonia and panic attacks in Parkinson disease.
METHOD: Structured Clinical Interview (SCID) ascertainment of Diagnostic and Statistical Manual of Mental Disorders, third edition, revised, disorders.
RESULTS: Generalized anxiety disorder was more common in dystonia while panic disorder was more common in Parkinson disease (P = 0.0018). Generalized anxiety developed more commonly after dystonia onset (i.e., secondary generalized anxiety) while panic attacks developed more commonly after Parkinson disease onset (P = 0.0132). Specific life prevalences were: generalized anxiety disorder, 7 subjects (25.0%) in dystonia versus 0 subjects (0.0%) in Parkinson disease; generalized anxiety, 11 (39.3%) versus 0 (0.0%); panic disorder, 2 (7.1%) versus 7 (25.0%); and panic attacks, 2 (7.1%) versus 9 (32.1%). Exploratory analysis in Parkinson disease indicated a relationship of panic disorder (P = 0.027) and secondary panic attacks (P = 0.0009) to motor block frequency. There were nonsignificant trends toward associations of secondary generalized anxiety with lower Mini Mental Status Examination scores (P = 0.058), and of secondary panic attacks with presence of a depressive disorder (P = 0.077). Depressive comorbidity rates are also presented.
CONCLUSIONS: These findings suggest relations of generalized anxiety with reduced pallidal inhibition of thalamofrontotemporal projections, and panic attacks with locus coeruleus dysfunction.