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OFF-Period Purposeless Groaning in Parkinsonism
Vikash Agarwal1, Jeyalakshmi Rajan2, Norlisah Ramli3
1Division of Neurology and the Mah Pooi Soo and Tan Chin Nam Centre for Parkinson's and Related Disorders, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; Department of Neurology, Gleneagles Global Health City, Chennai, Tamil Nadu, India.
Background:
Purposeless groaning is primarily encountered in patients with progressive supranuclear palsy and has also been reported to occur in advanced Parkinson's disease (PD).
Objective:
We describe a case of pronounced purposeless groaning occurring as a medication OFF-period nonmotor phenomenon in PD. To our knowledge, this has not been previously reported in the literature.
Methods And Materials:
We describe and provide video documentation of a patient with moderately advanced PD and motor fluctuations, in whom OFF-period groaning was reported by the family and observed during clinic consultations to be a prominent feature, occupying approximately 40% of his OFF periods as calculated from his PD diary.
Conclusions:
Although rare, OFF-period purposeless groaning in PD can be very disruptive and add significantly to caregiver burden. It is postulated to be a disinhibitory and perseverative behavior related to overactivation of the cingulo-periaqueductal circuit; further study is needed to delineate the underlying pathophysiological mechanisms.
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