Correlation with sympathetic skin response, 123I-MIBG scintigraphy, and 123I-FP-CIT SPECT in Parkinson's disease

Background Parkinson's disease (PD), and other parkinsonian syndromes are known to cause striatonigral dopaminergic system dysfunction and autonomic disturbances, including the vasomotor and sudomotor nervous systems. The detection of 123I-FP-CIT SPECT (DaT scan) imaging and autonomic dysfunction helps differentiate PD from multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). The sympathetic skin response (SSR) is a simple, non-invasive electrophysiological test that assesses the sympathetic sudomotor nervous system. It is reported that the SSR is impaired in patients with PD, MSA, and PSP. Objective To study the relationship between SSR, 123I-metaiodobenzylguanidine (MIBG) cardiac scintigraphy and DaT scan imaging parameters in patients with PD, MSA, and PSP. Methods The study included 62, 25, and 19 patients with PD, MSA, and PSP, respectively. The SSR, MIBG cardiac scintigraphy, and DaT scan imaging were examined. The amplitude and latency of the SSR were measured in all limbs and were compared with the results of MIBG cardiac scintigraphy and DAT scan imaging. Results The SSR amplitudes were lower than reported normal subjects' reference values in PD, MSA, and PSP. The SSR amplitude only correlated with MIBG cardiac scintigraphy and DaT scan imaging parameters in PD. Multiple regression analyses also showed a significant relationship between the amplitudes of SSR and DaT scan imaging in PD. Conclusion Unlike MSA, and PSP, the sudomotor nervous system is parallelly involved with cardiac sympathetic and central dopaminergic dysfunction from the early stage of PD.