BACKGROUND: A subgroup of patients initially diagnosed with Parkinson's disease (PD) turn out to have normal dopamine transporter single-photon emission computed tomography imaging and have been labeled as subjects without evidence of dopaminergic deficit (SWEDDs). In this study, we sought to further characterize these patients and have analyzed the frequency of nonmotor symptoms (NMS) in SWEDDs, PD patients, and healthy controls. METHODS: We analyzed the baseline clinical data of 412 PD patients, 184 controls, and 62 SWEDDs included in the Parkinson's Progression Marker Initiative study on a variety of different NMS questionnaires. RESULTS: Both PD patients and SWEDDs had greater frequency of NMS than healthy controls. Furthermore, some NMS, such as orthostatic hypotension as well as cardiovascular and thermoregulatory dysfunction were even more commonly reported in SWEDDs than in PD patients, whereas hyposmia was more common in PD, compared to SWEDDs. CONCLUSION: NMS are more frequent in SWEDDs than in controls, and autonomic dysfunction and orthostatic hypotension were even more common than in PD patients. These findings support the notion that SWEDDS represent a group of patients with still poorly understood pathophysiology.
BACKGROUND: A subgroup of patients initially diagnosed with Parkinson's disease (PD) turn out to have normal dopamine transporter single-photon emission computed tomography imaging and have been labeled as subjects without evidence of dopaminergic deficit (SWEDDs). In this study, we sought to further characterize these patients and have analyzed the frequency of nonmotor symptoms (NMS) in SWEDDs, PDpatients, and healthy controls. METHODS: We analyzed the baseline clinical data of 412 PDpatients, 184 controls, and 62 SWEDDs included in the Parkinson's Progression Marker Initiative study on a variety of different NMS questionnaires. RESULTS: Both PDpatients and SWEDDs had greater frequency of NMS than healthy controls. Furthermore, some NMS, such as orthostatic hypotension as well as cardiovascular and thermoregulatory dysfunction were even more commonly reported in SWEDDs than in PDpatients, whereas hyposmia was more common in PD, compared to SWEDDs. CONCLUSION:NMS are more frequent in SWEDDs than in controls, and autonomic dysfunction and orthostatic hypotension were even more common than in PDpatients. These findings support the notion that SWEDDS represent a group of patients with still poorly understood pathophysiology.
Authors: Iris van der Lijn; Gera A de Haan; Famke Huizinga; Fleur E van der Feen; A Wijnand F Rutgers; Catherina Stellingwerf; Teus van Laar; Joost Heutink Journal: J Parkinsons Dis Date: 2022 Impact factor: 5.520
Authors: Diane M A Swallow; Michael A Lawton; Katherine A Grosset; Naveed Malek; Callum R Smith; Nin P Bajaj; Roger A Barker; Yoav Ben-Shlomo; David J Burn; Thomas Foltynie; John Hardy; Huw R Morris; Nigel Williams; Nicholas W Wood; Donald G Grosset Journal: J Parkinsons Dis Date: 2016-03-19 Impact factor: 5.568