Relationship between cardiac 123I-metaiodobenzylguanidine scintigraphy and cardiovascular autonomic function test (standing test) in Parkinson's disease]

We investigated the correlation between results of 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy and those of cardiovascular autonomic function tests in patients with Parkinson's disease (PD). 123I-MIBG myocardial scintigraphy and a 5-minute standing test were performed in 50 patients with PD and in 19 control subjects. The value of the basal plasma noradrenaline (NA) level was used as an index of basal sympathetic nerve activity, and %NA was used to assess the response of sympathetic nerve activity. In addition, the parameters of DeltaBP and DeltaHR were evaluated to assess the autonomic response of the cardiovascular system. A mild, but significant correlation was observed between the myocardium to mediastinum (H/M) ratio and the values of the plasma NA baseline (r = 0.35, p < 0.05 in early image, r = 0.29, p < 0.05 in delay image). No significant correlation was observed between the H/M ratio and the other parameters (%NA, DeltaBP, DeltaHR). These results suggest that 123I-MIBG myocardial scintigraphy may be associated with the basal sympathetic nerve activity, but not with autonomic nervous response of the cardiovascular system in patients with PD.     

Cardiac 123I-MIBG scintigraphy can assess the disease severity and phenotype of PD

Objective: Cardiac ¹²³I-metaiodobenzylguanidine (MIBG) scintigraphy studies of patients with idiopathic Parkinson's disease (PD) found decreased uptake. Whether this decrease is associated with clinical severity as assessed by the Unified Parkinson's Disease Rating Scale (UPDRS) and the phenotypes of PD has not been determined. Methods: Cardiac MIBG scintigraphy was performed on 34 patients with PD, 7 with multiple system atrophy (MSA), 4 with dementia with Lewy bodies (DLB), and 11 normal controls (NCs). Early and delayed MIBG heart/mediastinum (H/M) ratios were evaluated. PD severity was assessed by the Hoehn and Yahr (H–Y) stage and UPDRS. Patients were grouped in two phenotypes, tremor and postural instability gait difficulty (PIGD)-dominant groups based on UPDRS components. Associations between MIBG uptake and age at onset, UPDRS, and disease phenotype were analyzed in each group. Results: The early H/M ratio was significantly lower in patients with PD (1.45±0.207) than in the NCs (2.08±0.231), and in those with MSA (1.99±0.284), but not in those with DLB (1.29±0.0435). The delayed H/M ratio for PD (1.33±0.276) also was significantly decreased as compared to the ratios for NCs (2.17±0.286) and MSA (2.16±0.414) but not DLB (1.16±0.0949). The early H/M ratio was significantly correlated with both UPDRS score and age at onset, whereas the delayed H/M ratio only was significantly correlated with age at onset. The PIGD-dominant group had significantly higher UPDRS scores and lower H/M ratios than the tremor-dominant group. Conclusion: Cardiac MIBG scintigraphy can be used to differentiate PD from MSA and NC, and to determine the disease severity and phenotypes of PD.     

Relation between autonomic dysfunction and progression of Parkinson's disease]

It has been claimed that cardiovascular dysfunction in patients with Parkinson's disease is less severe than multiple system atrophy. Autonomic dysfunction, however, increases with progression of Parkinson's disease. We studied the relation between autonomic dysfunction and disease severity by cardiovascular function testing with the Valsalva maneuver. The study group comprised 20 healthy controls (age, 52.7 +/- 13.6 years) and 31 patients with Parkinson's disease (59.0 +/- 7.2 years), including 13 who were previously untreated (55.0 +/- 6.2 years) and 18 who were receiving levodopa (61.8 +/- 7.1 years). The Valsalva maneuver was done having the subject exhale into a mouthpiece with an expiratory pressure of 40 mmHg for 15 seconds. Blood pressure and RR interval were measured during the Valsalva maneuver by tonometry, using a non-invasive blood pressure monitoring system (ANS 508, Nihon Colin Co., Ltd). Baroreceptor reflex sensitivities (BRS) of the second phase (BRS II) and fourth phase (BRS IV) of the Valsalva maneuver were calculated, and blood pressure elevations during the late second phase (IIp) and fourth phase (IVp) were measured. BRS II, BRS IV, and IVp in the patients of Parkinson's disease were significantly lower than those of healthy controls. BRS II, BRS IV, and IIp, however, did not significantly differ between the previously untreated patients and healthy controls. IVp of the previously untreated patients was significant lower than that of healthy controls. BRS II and BRS IV of patients with Parkinson's disease who were receiving levodopa for less than 5 years were significantly lower than those of the healthy controls. BRS II, BRS IV, and IIp decreased as disease duration increased, while IVp was unrelated to disease duration. These results suggest that patients with early Parkinson's disease have cardiac sympathetic autonomic dysfunction with maintained baroreceptor reflex sensitivity. Reduced baroreceptor reflex sensitivity was associated with levodopa treatment in patients with Parkinson's disease. Baroreceptor reflex sensitivity decreased and vasomotor sympathetic autonomic dysfunction developed as duration of disease increased.     

Cardiac sympathetic function in the patients with amyotrophic lateral sclerosis: analysis using cardiac [123I] MIBG scintigraphy

Amyotrophic lateral sclerosis (ALS), which is the most serious form of degenerative motor neuron disease in adults, is characterized by upper and lower motor neuron degeneration, skeletal muscle atrophy, paralysis, and death. Some patients with respiratory-dependent ALS die of sudden cardiac arrest or anoxic encephalopathy following circulatory collapse, which may be associated with sympathetic hyperactivity. Cardiac [¹²³I] MIBG scintigraphy is a diagnostic method of cardiac sympathetic function. However, few reports have addressed cardiac sympathetic function in ALS patients using this technique. We investigated cardiac sympathetic function in 63 ALS patients and 10 healthy volunteers using cardiac [¹²³I] metaiodobenzylguanidine (MIBG) scintigraphy [heart/mediastinum ratio (H/M ratio) in the early phase and washout ratio (WR)] at the time of diagnosis. The WR of cardiac [¹²³I] MIBG scintigraphy, which indicates cardiac sympathetic activity, was significantly increased in ALS patients compared with controls. ALS patients with an increased WR exhibited a significantly higher progression rate compared with those with normal WR. Moreover, the survival of ALS patients with increased WR was significantly decreased compared with those with normal WR. These results suggested that some patients with ALS have sympathetic hyperactivity at the time of diagnosis. ALS patients may suffer from chronic cardiac sympathetic hyperactivity, which is associated with sudden cardiac death and stress induced cardiomyopathy. Increased WR in cardiac [¹²³I] MIBG scintigraphy may be a predictive factor in ALS patients.     

帕金森病交感神经皮肤反应的临床研究

Objective To assess the value of detecting sympathetic skin response (SSR) in the diagnosis of autonomic dysfunction in patients with Parkinson disease (PD). Methods SSR measurement was performed in 47 PD patients and 20 healthy control subjects and the results were compared. The SSR was also comparatively analyzed between patients with and those without autonomic dysfimction. Results Compared with the healthy controls, the PD patients showed significantly lowered mean amplitude (2.56±1.47 vs 1.87±0.26, P<0.05) and prolonged latency (1.42±0.29 vs 1.55± 0.18, P<0.05) of the SSR in the upper limbs, with also lowered mean amplitude (0.76±0.39 vs 0.49±0.21, P<0.05) and prolonged latency (2.04±0.27 vs 2.13±0.16, P<0.05) in the lower limbs. Compared with the PD patients without autonomic dysfunction, those having autonomic dysfunction showed significantly lowered mean amplitude (1.89±0.33 vs 1.75±0.21, P<0.05) and prolonged latency (1.53±0.15 vs 1.56±0.17, P<0.05) of SSR in the upper limbs and lowered mean amplitude (0.51±0.17 vs 0.46±0.20,P<0.05) and prolonged latency (2.08±0.24 vs 2.17±0.18, P<0.05) in the lower limbs. Conclusion The results of SSR measurements are consistent with the clinical manifestations of the PD patients. SSR can be of value in the diagnosis of autonomic nerve dysfunction in PD.     

帕金森病交感神经皮肤反应的临床研究

Objective To assess the value of detecting sympathetic skin response (SSR) in the diagnosis of autonomic dysfunction in patients with Parkinson disease (PD). Methods SSR measurement was performed in 47 PD patients and 20 healthy control subjects and the results were compared. The SSR was also comparatively analyzed between patients with and those without autonomic dysfimction. Results Compared with the healthy controls, the PD patients showed significantly lowered mean amplitude (2.56±1.47 vs 1.87±0.26, P<0.05) and prolonged latency (1.42±0.29 vs 1.55± 0.18, P<0.05) of the SSR in the upper limbs, with also lowered mean amplitude (0.76±0.39 vs 0.49±0.21, P<0.05) and prolonged latency (2.04±0.27 vs 2.13±0.16, P<0.05) in the lower limbs. Compared with the PD patients without autonomic dysfunction, those having autonomic dysfunction showed significantly lowered mean amplitude (1.89±0.33 vs 1.75±0.21, P<0.05) and prolonged latency (1.53±0.15 vs 1.56±0.17, P<0.05) of SSR in the upper limbs and lowered mean amplitude (0.51±0.17 vs 0.46±0.20,P<0.05) and prolonged latency (2.08±0.24 vs 2.17±0.18, P<0.05) in the lower limbs. Conclusion The results of SSR measurements are consistent with the clinical manifestations of the PD patients. SSR can be of value in the diagnosis of autonomic nerve dysfunction in PD.     

帕金森病交感神经皮肤反应的临床研究

Objective To assess the value of detecting sympathetic skin response (SSR) in the diagnosis of autonomic dysfunction in patients with Parkinson disease (PD). Methods SSR measurement was performed in 47 PD patients and 20 healthy control subjects and the results were compared. The SSR was also comparatively analyzed between patients with and those without autonomic dysfimction. Results Compared with the healthy controls, the PD patients showed significantly lowered mean amplitude (2.56±1.47 vs 1.87±0.26, P<0.05) and prolonged latency (1.42±0.29 vs 1.55± 0.18, P<0.05) of the SSR in the upper limbs, with also lowered mean amplitude (0.76±0.39 vs 0.49±0.21, P<0.05) and prolonged latency (2.04±0.27 vs 2.13±0.16, P<0.05) in the lower limbs. Compared with the PD patients without autonomic dysfunction, those having autonomic dysfunction showed significantly lowered mean amplitude (1.89±0.33 vs 1.75±0.21, P<0.05) and prolonged latency (1.53±0.15 vs 1.56±0.17, P<0.05) of SSR in the upper limbs and lowered mean amplitude (0.51±0.17 vs 0.46±0.20,P<0.05) and prolonged latency (2.08±0.24 vs 2.17±0.18, P<0.05) in the lower limbs. Conclusion The results of SSR measurements are consistent with the clinical manifestations of the PD patients. SSR can be of value in the diagnosis of autonomic nerve dysfunction in PD.     

帕金森病交感神经皮肤反应的临床研究

Objective To assess the value of detecting sympathetic skin response (SSR) in the diagnosis of autonomic dysfunction in patients with Parkinson disease (PD). Methods SSR measurement was performed in 47 PD patients and 20 healthy control subjects and the results were compared. The SSR was also comparatively analyzed between patients with and those without autonomic dysfimction. Results Compared with the healthy controls, the PD patients showed significantly lowered mean amplitude (2.56±1.47 vs 1.87±0.26, P<0.05) and prolonged latency (1.42±0.29 vs 1.55± 0.18, P<0.05) of the SSR in the upper limbs, with also lowered mean amplitude (0.76±0.39 vs 0.49±0.21, P<0.05) and prolonged latency (2.04±0.27 vs 2.13±0.16, P<0.05) in the lower limbs. Compared with the PD patients without autonomic dysfunction, those having autonomic dysfunction showed significantly lowered mean amplitude (1.89±0.33 vs 1.75±0.21, P<0.05) and prolonged latency (1.53±0.15 vs 1.56±0.17, P<0.05) of SSR in the upper limbs and lowered mean amplitude (0.51±0.17 vs 0.46±0.20,P<0.05) and prolonged latency (2.08±0.24 vs 2.17±0.18, P<0.05) in the lower limbs. Conclusion The results of SSR measurements are consistent with the clinical manifestations of the PD patients. SSR can be of value in the diagnosis of autonomic nerve dysfunction in PD.     

帕金森病交感神经皮肤反应的临床研究

Objective To assess the value of detecting sympathetic skin response (SSR) in the diagnosis of autonomic dysfunction in patients with Parkinson disease (PD). Methods SSR measurement was performed in 47 PD patients and 20 healthy control subjects and the results were compared. The SSR was also comparatively analyzed between patients with and those without autonomic dysfimction. Results Compared with the healthy controls, the PD patients showed significantly lowered mean amplitude (2.56±1.47 vs 1.87±0.26, P<0.05) and prolonged latency (1.42±0.29 vs 1.55± 0.18, P<0.05) of the SSR in the upper limbs, with also lowered mean amplitude (0.76±0.39 vs 0.49±0.21, P<0.05) and prolonged latency (2.04±0.27 vs 2.13±0.16, P<0.05) in the lower limbs. Compared with the PD patients without autonomic dysfunction, those having autonomic dysfunction showed significantly lowered mean amplitude (1.89±0.33 vs 1.75±0.21, P<0.05) and prolonged latency (1.53±0.15 vs 1.56±0.17, P<0.05) of SSR in the upper limbs and lowered mean amplitude (0.51±0.17 vs 0.46±0.20,P<0.05) and prolonged latency (2.08±0.24 vs 2.17±0.18, P<0.05) in the lower limbs. Conclusion The results of SSR measurements are consistent with the clinical manifestations of the PD patients. SSR can be of value in the diagnosis of autonomic nerve dysfunction in PD.     

帕金森病交感神经皮肤反应的临床研究

目的 探讨交感神经皮肤反应(SSR)对帕金森病自主神经功能障碍的诊断价值.方法 对解放军第一○二医院神经内科自2006年7月至2008年8月门诊或住院的47例帕金森病患者及与之相匹配的20例健康人进行SSR检测,并对其中有自主神经功能障碍患者与无自主神经功能障碍患者的结果进行对比分析. 结果帕金森病患者与健康人相比,上肢潜伏期明显延长(1.55±0.18 vs 1.42±0.29),波幅明显降低(1.87±0.26 vs 2.56±1.47);下肢潜伏期明显延长(2.13±0.16vs 2.04±0.27),波幅明显降低(0.49±0.21 vs 0.76±0.39),差异均有统计学意义(P<0.05).有自主神经功能障碍患者与无自主神经功能障碍患者相比,上肢潜伏期明显延长(1.56 ± 0.17 vs 1.53 ± 0.15),波幅明显降低(1.75±0.21 vs 1.89±0.33);下肢潜伏期明显延长(2.17 ± 0.18 vs 2.08±0.24),波幅明显降低(0.46±0.20 vs 0.51±0.17),差异均有统计学意义(P<0.05). 结论 SSR检测结果与患者临床表现相一致,其对帕金森病患者的自主神经功能障碍有诊断价值.     

帕金森病交感神经皮肤反应的临床研究

Objective To assess the value of detecting sympathetic skin response (SSR) in the diagnosis of autonomic dysfunction in patients with Parkinson disease (PD). Methods SSR measurement was performed in 47 PD patients and 20 healthy control subjects and the results were compared. The SSR was also comparatively analyzed between patients with and those without autonomic dysfimction. Results Compared with the healthy controls, the PD patients showed significantly lowered mean amplitude (2.56±1.47 vs 1.87±0.26, P<0.05) and prolonged latency (1.42±0.29 vs 1.55± 0.18, P<0.05) of the SSR in the upper limbs, with also lowered mean amplitude (0.76±0.39 vs 0.49±0.21, P<0.05) and prolonged latency (2.04±0.27 vs 2.13±0.16, P<0.05) in the lower limbs. Compared with the PD patients without autonomic dysfunction, those having autonomic dysfunction showed significantly lowered mean amplitude (1.89±0.33 vs 1.75±0.21, P<0.05) and prolonged latency (1.53±0.15 vs 1.56±0.17, P<0.05) of SSR in the upper limbs and lowered mean amplitude (0.51±0.17 vs 0.46±0.20,P<0.05) and prolonged latency (2.08±0.24 vs 2.17±0.18, P<0.05) in the lower limbs. Conclusion The results of SSR measurements are consistent with the clinical manifestations of the PD patients. SSR can be of value in the diagnosis of autonomic nerve dysfunction in PD.     

帕金森病交感神经皮肤反应的临床研究

Objective To assess the value of detecting sympathetic skin response (SSR) in the diagnosis of autonomic dysfunction in patients with Parkinson disease (PD). Methods SSR measurement was performed in 47 PD patients and 20 healthy control subjects and the results were compared. The SSR was also comparatively analyzed between patients with and those without autonomic dysfimction. Results Compared with the healthy controls, the PD patients showed significantly lowered mean amplitude (2.56±1.47 vs 1.87±0.26, P<0.05) and prolonged latency (1.42±0.29 vs 1.55± 0.18, P<0.05) of the SSR in the upper limbs, with also lowered mean amplitude (0.76±0.39 vs 0.49±0.21, P<0.05) and prolonged latency (2.04±0.27 vs 2.13±0.16, P<0.05) in the lower limbs. Compared with the PD patients without autonomic dysfunction, those having autonomic dysfunction showed significantly lowered mean amplitude (1.89±0.33 vs 1.75±0.21, P<0.05) and prolonged latency (1.53±0.15 vs 1.56±0.17, P<0.05) of SSR in the upper limbs and lowered mean amplitude (0.51±0.17 vs 0.46±0.20,P<0.05) and prolonged latency (2.08±0.24 vs 2.17±0.18, P<0.05) in the lower limbs. Conclusion The results of SSR measurements are consistent with the clinical manifestations of the PD patients. SSR can be of value in the diagnosis of autonomic nerve dysfunction in PD.     

帕金森病交感神经皮肤反应的临床研究

Objective To assess the value of detecting sympathetic skin response (SSR) in the diagnosis of autonomic dysfunction in patients with Parkinson disease (PD). Methods SSR measurement was performed in 47 PD patients and 20 healthy control subjects and the results were compared. The SSR was also comparatively analyzed between patients with and those without autonomic dysfimction. Results Compared with the healthy controls, the PD patients showed significantly lowered mean amplitude (2.56±1.47 vs 1.87±0.26, P<0.05) and prolonged latency (1.42±0.29 vs 1.55± 0.18, P<0.05) of the SSR in the upper limbs, with also lowered mean amplitude (0.76±0.39 vs 0.49±0.21, P<0.05) and prolonged latency (2.04±0.27 vs 2.13±0.16, P<0.05) in the lower limbs. Compared with the PD patients without autonomic dysfunction, those having autonomic dysfunction showed significantly lowered mean amplitude (1.89±0.33 vs 1.75±0.21, P<0.05) and prolonged latency (1.53±0.15 vs 1.56±0.17, P<0.05) of SSR in the upper limbs and lowered mean amplitude (0.51±0.17 vs 0.46±0.20,P<0.05) and prolonged latency (2.08±0.24 vs 2.17±0.18, P<0.05) in the lower limbs. Conclusion The results of SSR measurements are consistent with the clinical manifestations of the PD patients. SSR can be of value in the diagnosis of autonomic nerve dysfunction in PD.     

Measures of cardiovascular autonomic regulation derived from spontaneous methods and the Valsalva maneuver

The response of heart rate to a given change of systolic blood pressure is a fundamental characteristic of the cardiovascular system. The assessment of baroreflex gain (BRS) as an index of baroreflex function is based on the quantification of RR interval changes related to blood pressure changes. The spontaneous sequence and cross spectral methods describe baroreflex gain derived from spontaneous fluctuations of these parameters, yielding the up sequence and down sequence BRS and the alfa index. Phase IV of the Valsalva maneuver is also used to calculate cardiac vagal baroreflex gain. In this study, we compared the two spontaneous methods and the Valsalva maneuver in assessing baroreflex gain in 56 healthy volunteers. The BRS values calculated from different methods were as follows: up sequence BRS 12 +/- 8.6 ms/mm Hg, down sequence BRS 10 +/- 6.1 ms/mm Hg, low frequency alfa index 12.1 +/- 8.2 ms/mm Hg, Valsalva BRS 9.7 +/- 7.2 ms/mm Hg. We found close relationship between baroreflex gain derived from up and down sequences (R = 0.91, p < 0.001), down sequence BRS and low frequency alfa index (R = 0.81, p < 0.001); significant correlation between up sequence BRS and low frequency alfa index (R = 0.65, p < 0.001), the Valsalva-derived BRS and down sequence BRS (R = 0.37, p = 0.043), but no correlation between the Valsalva BRS and up sequence BRS, the Valsalva BRS and low frequency alfa index. BRS values calculated by different methods decreased with increasing age. There was no influence of age on mean arterial blood pressure elevation in late phase II of the Valsalva maneuver, nor any indication that the Valsalva BRS was related to the MAP changes. We concluded that all of these methods are useful in calculating baroreflex gain, but owing to the differences in underlying physiological mechanisms, they are not necessarily in correlation with each other.     

123I-MIBG cardiac uptake,smell identification and 123I-FP-CIT SPECT in the differential diagnosis between vascular parkinsonism and Parkinson's disease

Vascular parkinsonism (VP) may occur as a distinct clinicopathological entity but the comorbid presence of vascular damage in Parkinson's disease (PD) is very frequent too. This differential diagnosis has therapeutic and prognostic implications but remains challenging as the usefulness of a number of supporting tools is still controversial.ObjectiveTo ascertain the clinical value of cardiac ¹²³I-meta-iodobenzylguanidine (¹²³I-MIBG) SPECT, olfactory function and ¹²³I-FP-CIT SPECT as supporting tools in the differential diagnosis between VP and PD.MethodsCross-sectional study of 15 consecutive patients with suspected VP, 15 PD patients and 9 healthy subjects. Cardiac ¹²³I-MIBG SPECT (heart-to-mediastinum ratio) and olfactory testing (University of Pennsylvania Smell Identification Test-UPSIT) were performed in all of them. ¹²³I-FP-CIT SPECT was performed in VP-suspected patients.ResultsHeart-to-mediatinum ratio was significant lower in suspected VP (mean 1.45) and PD (mean 1.16) compared to control group (mean 1.69) (p = 0.017 and p < 0.0001). VP patients presented a higher ratio than PD patients (p = 0.001). Control group presented a significant higher UPSIT score (mean 30.71) when compared to both VP (mean 18.33) and PD (mean 15.29) (p = 0.001 for both groups). Those VP with a cardiac ¹²³I-MIBG non suggestive of PD were more likely to have a higher UPSIT score (p = 0.006). ¹²³I-FP-CIT SPECT imaging was heterogeneous (7/15 VP normal, 3/15 abnormal suggestive of PD and 5/15 abnormal but atypical for PD).ConclusionsThe use of cardiac ¹²³I-MIBG SPECT and to a lesser extent UPSIT could assist the differential diagnosis between VP and PD in subjects in which the diagnosis remains uncertain despite ¹²³I-FP-CIT SPECT imaging.     

Respiratory function impairment in patients with Parkinson's disease--a consideration on the possible pathogenetic relation to autonomic dysfunction]

To investigate the characteristics and clinical significance of respiratory function in patients with Parkinson's disease (PD), we studied 38 patients (male, 19; female, 19: mean age, 65.5 years: mean duration of disease, 6.7 years) who had no history of respiratory disease and smoking. Fifty three non-respiratory disease subjects (male, 26; female, 27: mean age, 67.6 years) were served as age-matched control. We measured spirometry and maximal expiratory flow-volume curve in all patients, and analyzed the relations between respiratory function variables and clinical profiles. The clinical disability of PD was indicated by Hoehn-Yahr (H-Y) scale. The number of PD patients was 15 in H-Y 2, 18 in H-Y 3 and 5 in H-Y 4, respectively. The values of % VC, %FEV 1, FEV 1/FVC, %PEFR, % V50 in H-Y 4 group were significantly smaller than those in H-Y 2 and 3 groups. Small airway dysfunction (SAD) was represented by abnormality of % V25, % V50/V25. The prevalence of impairment in % V25 and % V50/V25 was detected in 13 patients (34.2%) and 15 patients (39.5%), respectively, this was significantly higher than age-matched controls. However, the mean value and prevalence of impairment in % V25, % V50/V25 were not affected by H-Y scale and duration of disease or ideal body weight (%predicted value). Twenty seven patients showed normal ventilatory function based on % VC over 80% and FEV 1/FVC over 70%. The prevalence of impairment in % V25, % V50/V25 was detected in 8 patients (29.6%), 9 patients (33.3%), respectively, among 27 patients with normal ventilatory function. These results suggest that ventilatory dysfunction is concerned with clinical disability but SAD which is independent of clinical disability seen prevalently in patients with PD. It is widely accepted that patients with PD frequently have cardiac or bowel dysfunction based on the visceral autonomic dysfunction. We hypothesize that SAD may also be caused by possible autonomic dysfunction in patients with PD.     

Correlation between cardiac 123I-MIBG and odor identification in patients with Parkinson's disease and multiple system atrophy.

We investigated an association between olfaction and cardiac (123)I-metaiodobenzylguanidine (MIBG) uptake in patients with Parkinson's disease (PD) and multiple system atrophy (MSA). There was a significant positive correlation between cardiac MIBG uptake and the Cross-Cultural Smell Identification (CCSI) score in patients with PD (r = 0.56; P = 0.003) independent of the disease duration or clinical rating of motor status. However, patients with MSA did not show a significant correlation between cardiac MIBG uptake and the CCSI score. Our findings suggest that the functional losses of the olfactory and cardiac sympathetic systems are closely coupled in PD.