The syndrome of inappropriate antidiuretic hormone secretion (SIADH) can be caused by a variety of drugs. Dopaminergic drugs might enhance the secretion of the antidiuretic hormone arginine vasopressin by reducing γ-amino butyric acid release through the dopaminergic receptor in supraoptic nucleus. A 75-year-old woman with Parkinson’s disease developed asthenia, delirium, aggravated parkinsonian symptoms, and hypotonic hyponatremia along with the diagnostic criteria for SIADH during dose escalation of pramipexole. After pramipexole withdrawal, these symptoms disappeared, and sodium levels returned to normal values. The serum sodium levels of patients receiving pramipexole should be monitored, especially during dose escalation.

The objective of this study is to investigate the clinical significance of a specific behavior of misplacing items in a refrigerator (i.e., placing extremely unusual things such as remote control and/or cellular phone in a refrigerator) as a symptom of cognitive dysfunction. Patients with memory complaints were asked whether they ever experienced misplacing items in a refrigerator, such as placing a remote control, a cellular phone, or other extremely unusual things inside a refrigerator (referred to as the ‘fridge sign’). Among the 2172 individuals with memory complaints, 55 (2.5%) experienced symptoms of the ‘fridge sign’. We investigated the cognitive profiles of ‘fridge sign’-positive patients and performed follow-up evaluations with neuropsychological tests or telephone interviews. The ‘fridge sign’ was mostly found in individuals diagnosed as subjective cognitive decline (n = 33, 60%) or mild cognitive impairment (MCI, n = 20, 36.4%) with depressive mood and was relatively rare in dementia states (n = 2, 3.5%). Moreover, none of the ‘fridge sign’-positive patients showed significant cognitive decline over the follow-up period. We compared the cognitive profiles and the clinical progression of 20 ‘fridge sign’-positive MCI patients and 40 ‘fridge sign’-negative MCI patients. ‘Fridge sign’-positive MCI patients had worse scores on the Stroop test color reading and had higher scores on the geriatric depression scale than ‘fridge sign’-negative MCI patients, which indicates that the ‘fridge sign’ could be indicative of selective attention deficit in patients with depression rather than indicative of cognitive decline related to dementia.

Background: Cerebral small vessel disease (SVD) induces vascular cognitive impairment (VCI) such as subcortical vascular dementia (SVaD) and subcortical vascular mild cognitive impairment (svMCI). We compared MRI parameters between SVaD and svMCI and determined which MRI parameters best correlated with cognitive function and disability on cross-sectional and longitudinal analyses within them. Methods: Twenty-four patients with SVaD and twelve with svMCI were recruited. They underwent multimodal MRIs including fluid-attenuated inversion recovery lesion load, lacunar infarct number, and fractional anisotropy (FA) and mean diffusivity (MD) from diffusion tensor imaging (DTI), neuropsychological testing, Sum of Boxes of Clinical Dementia Rating Scale (CDR-SB), Barthel Index, and the Korean version of a Geriatric Depression Scale (GDS-K). Seventeen patients were retested after 20 months for a brain MRI and clinical evaluation. Results: There were significant differences in average MD and peak height of MD histograms within normal-appearing brain tissue (NABT) between SVaD and svMCI patients. In the cross-sectional analysis, average MD within NABT significantly correlated with the composite neuropsychology score (r = -0.80, p < 0.001), the composite executive function score (r = -0.67, p < 0.001), and the CDR-SB (r = 0.54, p = 0.001), and the Barthel Index correlated with peak heights of the MD histograms (r = 0.37, p = 0.03) in NABT. Changes of CDR-SB was associated with changes of average MD within WMH (r = 0.57, p = 0.02), and changes of GDS-K was associated with changes of WMH volume (r = 0.51, p = 0.04) on a longitudinal scale. Conclusions: DTI parameters in NABT correlated with cognitive impairment and disability in VCI associated with SVD. Clinical progression of SVD was associated with some increment of WML volume and ultrastructural changes in WMH.

Background:Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by motor and nonmotor symptoms such as cognitive impairment and neuropsychiatric symptoms. The aim of this study was to investigate the spectrum of neuropsychiatric symptoms in PD according to cognitive function. Methods: One hundred twenty seven patients with PD were consecutively recruited. They had undergone an intensive interview with a neurologist and the Seoul Neuropsychological Screening Battery-dementia version, and were divided into three groups: 27 patients in PD with normal cognition (PDNC), 57 in PD with mild cognitive impairment (PDMCI), and 43 in PD with Dementia (PDD). Forty five healthy controls without memory complaints were also recruited. The caregivers of all participants administered the Caregiver-Administered Neuropsychiatric Inventory (CGA-NPI). Results: There were significant differences in the CGA-NPI score (22.8 ± 20.9 vs. 6.4 ± 10.1 vs. 1.7 ± 3.9 vs. 1.0 ± 1.6, p < 0.001), and the prevalence of neuropsychiatric symptoms (100% vs. 64.9% vs. 37.0% vs. 44.4%, p < 0.001) among PDD, PDMCI, PDNC and control groups. Depression was the most common symptom (43.3%), followed by anxiety (31.5%), apathy (26.8%), and night-time behavior (26.8%) in all PD patients. Delusion, hallucination, and aberrant motor behavior were observed frequently in PDD, but were rare in PDMCI. Conclusions: Depression was the most common neuropsychiatric symptom in PD. The presence of delusion, hallucination, or aberrant motor behavior may suggest PDD. The neuropsychiatric symptoms were not prevalent in PD with normal cognition.

Background: Atrial fi brillation (AF) and patent foramen ovale (PFO) are established sources of cardioembolism. We investigated differences in stroke outcome and patterns between PFO and AF. Methods: We performed a retrospective review of the medical records and brain MR images of patients with AF or PFO from the prospective acute stroke and transient ischemic attack registry. Infarct pattern and volume on diffusion-weighted imaging, and the national institutes of health stroke scale (NIHSS) on admission were compared between patients with AF and PFO. Results: From June 2005 to July 2008, a total of 289 subjects were enrolled (AF group, n=156; PFO group, n=133). Infarct pattern analyzed with MR images revealed that multiple vascular territorial infarction was more prevalent in AF group than in PFO group (26.9% vs. 8.3%, P<0.01). A probable cardiac embolism, radiologically defi ned as territorial infarction without symptomatic steno-occlusion of the corresponding artery, was more frequently documented in AF group than in PFO group (71.8% vs. 41.4%, P<0.01) The infarct volume of PFO was smaller than that of AF. Compared to AF, PFO was associated with the mild neurologic defi cit (NIHSS≤3) after adjusting age, sex and previous stroke history. Conclusion: These results suggested that AF and PFO had different characteristics such as infarct patterns and initial clinical severity although both are classifi ed as cardioembolism.