Cognitive impairments are common even in newly diagnosed Parkinson disease patients, with deficits being most prominent in the domains of memory and executive functions. Older age at disease onset is likely to be an important determinant of cognitive dysfunction in Parkinson disease.

No abstract

Subthalamic nucleus deep brain stimulation improves motor symptoms and quality of life in advanced Parkinson's disease. As after other life-altering surgeries, suicides have been reported following deep brain stimulation for movement disorders. We sought to determine the suicide rate following subthalamic nucleus deep brain stimulation for Parkinson's disease by conducting an international multicentre retrospective survey of movement disorder and surgical centres. We further sought to determine factors associated with suicide attempts through a nested case-control study. In the survey of suicide rate, 55/75 centres participated. The completed suicide percentage was 0.45% (24/5311) and attempted suicide percentage was 0.90% (48/5311). Observed suicide rates in the first postoperative year (263/100,000/year) (0.26%) were higher than the lowest and the highest expected age-, gender- and country-adjusted World Health Organization suicide rates (Standardized Mortality Ratio for suicide: SMR 12.63-15.64; P < 0.001) and remained elevated at the fourth postoperative year (38/100,000/year) (0.04%) (SMR 1.81-2.31; P < 0.05). The excess number of deaths was 13 for the first postoperative year and one for the fourth postoperative year. In the case-control study of associated factors, 10 centres participated. Twenty-seven attempted suicides and nine completed suicides were compared with 70 controls. Postoperative depression (P < 0.001), being single (P = 0.007) and a previous history of impulse control disorders or compulsive medication use (P = 0.005) were independent associated factors accounting for 51% of the variance for attempted suicide risk. Attempted suicides were also associated (P < 0.05) with being younger, younger Parkinson's disease onset and a previous suicide attempt. Completed suicides were associated with postoperative depression (P < 0.001). Postoperative depression remained a significant factor associated with attempted and completed suicides after correction for multiple comparisons using the stringent Bonferroni correction. Mortality in the first year following subthalamic nucleus deep brain stimulation has been reported at 0.4%. Suicide is thus one of the most important potentially preventable risks for mortality following subthalamic nucleus deep brain stimulation for Parkinson's disease. Postoperative depression should be carefully assessed and treated. A multidisciplinary assessment and follow-up is recommended.

Results-Compared with an age matched control group striatal ["23I]FP-CIT uptake in patients with Parkinson's disease was decreased, and this result was measurable three hours after injection of the radioligand. In the Parkinson's disease group the uptake in the putamen was reduced more than in the caudate nucleus. The contralateral striatal uptake of ["23I]FP-CIT was significantly lower than the ipsilateral striatal uptake in the Parkinson's disease group. Specific to non-specific striatal uptake ratios correlated with the Hoehn and Yahr stage. A subgroup of patients with early Parkinson's disease also showed significantly lower uptake in the putamen and lower putamen:caudate ratios than controls.

Axial impairment is strongly associated with disability in patients with mild to moderate Parkinson disease (PD). Self-report indices of mood status and axial impairment are identified as the main determinants of poor quality of life (QoL). The results of this study may help to identify patients with PD at risk for functional dependence and reduced QoL.

Approximately one-third of patients with newly diagnosed PD fulfill the consensus criteria for PD-MCI; after 5 years, this proportion is approximately 50% of patients without dementia. The criteria have good interrater and intrarater reliability.

(i Neurol Neurosurg Psychiatry 1996;61:70-74)

Bilateral subthalamic nucleus stimulation has an adverse effect on executive functions with implications for daily life of the patients and their relatives.