Increased substantia nigra echogenicity correlated with visual hallucinations in Parkinson's disease: a Chinese population-based study

Correlation Between Substantia Nigra Hyperechogenicity and Iron Metabolism in the Postural Instability Gait Difficulty Subtype of Parkinson's Disease

OBJECTIVE

The correlation between substantia nigra (SN) hyperechogenicity on transcranial sonography (TCS) and serum iron metabolism parameters in patients with the postural instability gait difficulty (PIGD) subtype of Parkinson's disease (PD) was investigated so as to explore the pathological mechanism of SN hyperechogenicity.

METHODS

The study enrolled 95 PIGD patients recruited by the Parkinson's Disease Specialty in the Second Affiliated Hospital of Soochow University during June 2019-2021. On the basis of the TCS results, the PIGD patients were assigned to the PD with SN hyperechogenicity (SN+) group (n = 60) and PD without SN hyperechogenicity (SN-) group (n = 35). Meanwhile, 49 sex- and age-matched healthy individuals were included in the control group. All participants underwent blood tests. Differences in the iron metabolism parameters among the three groups and the correlation between SN hyperechogenicity and serum iron metabolism parameters were analyzed.

RESULTS

Serum ferritin, ceruloplasmin and transferrin levels were lower in the SN+ and SN- groups than in the control group (all p values <0.001). The serum ceruloplasmin level was lower in the SN+ group (0.23 [0.20, 0.25] g/L) than in the SN- group (0.25 [0.22, 0.29] g/L) (p = 0.001), and the proportion of patients with an abnormal ceruloplasmin level was higher in the SN+ group than in the SN- group (43.3% [26/60] vs. 14.3% [5/35], χ2 = 8.484, p = 0.004). Moreover, the SN hyperechogenicity area was negatively correlated with the serum transferrin level (r = -0.428, p < 0.001).

CONCLUSION

Decreased serum ceruloplasmin levels may be associated with SN hyperechogenicity development in PIGD patients. The SN hyperechogenicity area is negatively correlated with the serum transferrin level.

Substantia Nigra Echogenicity Signal Correlated with Clinical Features in Patients with Parkinson's Disease in Xinjiang

Background

Transcranial sonography (TCS) is a noninvasive test that can reveal structural changes in the substantia nigra (SN) in Parkinson's disease (PD). The purpose of this study was to investigate the relationship between SN signatures and clinical features in PD patients in a multiethnic region of China.

Methods

A total of 147 patients with PD were included in the study, and all of whom had underwent a TCS examination. Clinical information was collected from PD patients, and motor and nonmotor symptoms were assessed using assessment scales.

Results

There were differences in the substantia nigra hyperechogenicity (SNH) area between age of onset, visual hallucinations (VH), and UPDRS3.0 II scores (P < 0.05), patients with late onset PD had a greater SNH area than early onset (0.326 ± 0.352 vs. 0.171 ± 0.194), and PD patients presenting with VH had a greater SNH area than those without hallucinations (0.508 ± 0.670 vs. 0.278 ± 0.659), and further multifactorial analysis showed that a high SNH area was an independent risk factor for development of VH. The area under the ROC curve for predicting VH from the SNH area in PD patients was 0.609 (95% CI: 0.444-0.774). There was a positive correlation between the SNH area and UPDRS3.0-II scores, but further multifactorial analysis showed that SNH was not an independent predictor of the UPDRS3.0-II score.

Conclusion

A high SNH area is an independent risk factor for development of VH, there is a positive correlation between the SNH area and UPDRS3.0 II score, and TCS has guiding significance in predicting clinical VH symptoms and activities of daily living in PD patients.

Quantitative Transcranial Sonography Evaluation of Substantia Nigra Hyperechogenicity Is Useful for Predicting Levodopa-Induced Dyskinesia in Parkinson Disease

Levodopa-induced dyskinesia (LID) is a common motor complication in Parkinson disease (PD). Abnormal substantia nigra hyperechogenicity (SN+), detected by transcranial sonography (TCS), plays an important role in the differential diagnosis of PD. The purpose of this study was to investigate the predictive performance of quantitative SN+ evaluations for LID. Five hundred sixty-two individuals were included in our analysis, and 198 individuals were followed up. These individuals were divided into two groups at baseline: the PD with LID (PD+LID) group and the PD without LID (PD-LID) group. The association between total hyperechogenic area of the SN on both sides (SN_T) and LID was analyzed by binary logistic analysis. A binary logistic regression model including SN_T was applied to establish a model for discriminating LID. At baseline, 105 (18.7%) individuals were diagnosed with LID. The PD+LID group had a longer disease duration, shorter education duration, higher levodopa equivalent doses, greater disease severity and larger SN_T. A model combining clinical features and SN_T was further established with better efficiency (area under the receiver operating characteristic curve = 0.839). One hundred ninety-eight individuals were followed up; individuals with a larger SN_T and a higher predicted probability were more likely to develop LID in our follow-up. Our study determined that quantitative TCS evaluation of SN echogenicity is useful in predicting LID in PD.

Risk of Cognitive Impairment in Patients With Parkinson's Disease With Visual Hallucinations and Subjective Cognitive Complaints

BACKGROUND AND PURPOSE

Visual hallucinations (VH) and subjective cognitive complaints (SCC) are associated with cognitive impairment (CI) in Parkinson's disease. Our aims were to determine the association between VH and SCC and the risk of CI development in a cohort of patients with Parkinson's disease and normal cognition (PD-NC).

METHODS

Patients with PD-NC (total score of >80 on the Parkinson's Disease Cognitive Rating Scale [PD-CRS]) recruited from the Spanish COPPADIS cohort from January 2016 to November 2017 were followed up after 2 years. Subjects with a score of ≥1 on domain 5 and item 13 of the Non-Motor Symptoms Scale at baseline (V0) were considered as "with SCC" and "with VH," respectively. CI at the 2-year follow-up (plus or minus 1 month) (V2) was defined as a PD-CRS total score of <81.

RESULTS

At V0 (n=376, 58.2% males, age 61.14±8.73 years [mean±SD]), the frequencies of VH and SCC were 13.6% and 62.2%, respectively. VH were more frequent in patients with SCC than in those without: 18.8% (44/234) vs 4.9% (7/142), p<0.0001. At V2, 15.2% (57/376) of the patients had developed CI. VH presenting at V0 was associated with a higher risk of CI at V2 (odds ratio [OR]=2.68, 95% confidence interval=1.05-6.83, p=0.0.039) after controlling for the effects of age, disease duration, education, medication, motor and nonmotor status, mood, and PD-CRS total score at V0. Although SCC were not associated with CI at V2, presenting both VH and SCC at V0 increased the probability of having CI at V2 (OR=3.71, 95% confidence interval=1.36-10.17, p=0.011).

CONCLUSIONS

VH were associated with the development of SCC and CI at the 2-year follow-up in patients with PD-NC.

Clinical Features in Parkinson's Disease Patients with Hyperechogenicity in Substantia Nigra: A Cross-Sectional Study

BACKGROUND

Transcranial ultrasound (TCS) can be used to reveal structural changes in the substantia nigra (SN) and is a potential tool for the early diagnosis of Parkinson's disease (PD). This study aimed to explore the relationship between substantia nigra hyperechogenicity (SNH) and the clinical features of PD patients.

METHODS

A total of 96 PD patients were included in our study. All patients were detected by TCS and divided into two groups: PD patients with SNH (PDSN+) and those with normal SN echogenicity (PDSN-). The Unified Parkinson's Disease Rating Scale (UPDRS) and the Hoehn & Yahr stage were used to assess the extent of disease-related disability of the PD patients. Non-motor symptoms were evaluated by using several scales. The instrumented stand and walk test was performed on all subjects, and gait data were gathered using a JiBuEn gait analysis system.

RESULTS

Seventy-five PD patients were successfully assessed by TCS. We found that SNH was associated with a higher UPDRS II scores (p = 0.028). In addition, compared with PDSN- group, the PDSN+ group exhibited more severe gait impairment, including increased variability in stride length (p = 0.042), decreased heel strike angle (p = 0.017), decreased range of motion of hip joints (p = 0.031), and a more asymmetrical walking pattern (p = 0.028).

CONCLUSION

Our study demonstrated that SNH significantly correlated with activities of daily living and gait impairment in Chinese patients with PD, suggesting the formation of SNH might be a dynamic biomarker reflecting disease severity.

Brainstem Pathologies Correlate With Depression and Psychosis in Parkinson's Disease

BACKGROUND

The pathological hallmarks of Parkinson's disease include intraneuronal Lewy bodies, neuronal loss, and gliosis. We aim to correlate Parkinson's disease neuropsychiatric symptoms, (e.g., depression, psychosis, and anxiety) with the severity of neuropathology in the substantia nigra and locus coeruleus.

METHODS

The brains of 175 participants with a primary pathologic diagnosis of Parkinson's disease were analyzed semi-quantitatively to ascertain the burden of neuronal loss and gliosis and Lewy body pathology within the locus coeruleus and substantia nigra. Participants' history of anxiety, depression, and psychosis were determined using a chart-extracted medical history or record of formal psychiatric evaluation.

RESULTS

Of the sample, 56% (n = 98), 50% (n = 88), and 31.25% (n = 55) of subjects had a diagnosis of psychosis, depression, and anxiety, respectively. Psychosis (χ² = 7.1, p = 0.008, df = 1) and depression (χ² = 7.2, p = 0.007, df = 1) were associated with severe neuronal loss and gliosis in the substantia nigra but not in the locus coeruleus. No association was observed between anxiety and neuronal loss and gliosis in either region. No neuropsychiatric symptoms were associated with Lewy body score. After controlling for disease duration and dementia, psychosis (odds ratio [OR]: 3.1, 95% confidence interval [CI]: 1.5-6.4, χ² = 9.4, p = 0.012, df = 1) and depression (OR: 2.6, 95% CI: 1.3-5.0, χ² = 7.9, p = 0.005, df = 1) remained associated with severe neuronal loss and gliosis in the substantia nigra.

CONCLUSION

These results suggest that psychosis and depression in Parkinson's disease are associated with the underlying neurodegenerative process and demonstrate that cell loss and gliosis may be a better marker of neuropsychiatric symptoms than Lewy body pathology.

Neurosonological Findings Related to Non-Motor Features of Parkinson's Disease: A Systematic Review

Non-motor symptoms (NMS) in Parkinson’s disease (PD), including neuropsychiatric or dysautonomic complaints, fatigue, or pain, are frequent and have a high impact on the patient’s quality of life. They are often poorly recognized and inadequately treated. In the recent years, the growing awareness of NMS has favored the development of techniques that complement the clinician’s diagnosis. This review provides an overview of the most important ultrasonographic findings related to the presence of various NMS. Literature research was conducted in PubMed, Scopus, and Web of Science from inception until January 2021, retrieving 23 prospective observational studies evaluating transcranial and cervical ultrasound in depression, dementia, dysautonomic symptoms, psychosis, and restless leg syndrome. Overall, the eligible articles showed good or fair quality according to the QUADAS-2 assessment. Brainstem raphe hypoechogenicity was related to the presence of depression in PD and also in depressed patients without PD, as well as to overactive bladder. Substantia nigra hyperechogenicity was frequent in patients with visual hallucinations, and larger intracranial ventricles correlated with dementia. Evaluation of the vagus nerve showed contradictory findings. The results of this systematic review demonstrated that transcranial ultrasound can be a useful complementary tool in the evaluation of NMS in PD.

The relationship between obstructive sleep apnea and Parkinson's disease: a systematic review and meta-analysis

BACKGROUND

Obstructive sleep apnea (OSA) is a common sleep disorder in Parkinson's disease (PD). However, the relationship between OSA and PD is still inconsistent. Our study was aimed to evaluate the relationship between PD and OSA.

METHODS

Studies on OSA and PD were searched using PubMed, Embase, Web of Science, Cochrane library, and Chinese National Knowledge Infrastructure databases. Review Manager 5.3 software was used to calculate the pooled estimate effect. The inverse variance model was used to pool the mean difference (MD) or hazard ratios (HRs); the Mantel-Haenszel method was used to pool the odds ratio (OR). Heterogeneity among the studies was assessed using I² statistic and Q test.

RESULTS

A total of 12 studies with 93,332 cases were deemed eligible and included in our meta-analysis. Overall, the occurrence of PD was more frequent in patients with OSA (HR 1.59, 95% CI, 1.36-1.85). The subgroup analysis demonstrated the risk similarly by sex. Male and female had HR of incident PD with OSA of 1.56 (95% CI, 1.30-1.87) and 1.60 (95% CI, 1.21-2.11), respectively. The incidence of OSA did not increase in PD patients (OR 0.89, 95% CI, 0.53-1.49). The MD of apnea-hypopnea index (AHI) in PD patients was also not statistically significant (P = 0.5).

CONCLUSIONS

The results indicate that OSA is one of independent risk factors of PD. However, OSA does not seem to be abnormally frequent in PD.