1.105 Stressful life events and Parkinson\'s disease: A case-control study

Poster Presentations: Parkinsonism Method: A total of 102 case subjects and 69 family controls who self-reported environmental exposures. Associations between PD and environmental measures (history, status, dosage, duration, and intensity) of smoking, coffee, caffeine, nonsteroidal anti-inflammatory drugs, and non-aspirin nonsteroidal anti-inflammatory drugs were examined using generalized estimating equations with an independent correlation matrix while controlling for age and sex. Results: Individuals with PD were significantly less likely to report ever smoking (odds ratio = 0.49; 94% confidence interval, 0.33−0.64). Additional measures of smoking revealed significant inverse associations with PD (P < 0.04) and trends in odds ratios (P < 0.005). Increasing intensity of coffee drinking was inversely associated with PD (test for trend P = 0.04). Increasing dosage (trend P = 0.005) and intensity (trend P = 0.02) of total caffeine consumption were also inversely associated, with high dosage presenting a significant inverse association for PD (odds ratio = 0.61; 93% confidence interval, 0.33−0.87). There were no significant associations between nonsteroidal anti-inflammatory drugs and PD. Conclusion: Inverse associations of smoking and caffeine were corroborated using families with PD, thus emphasizing smoking and caffeine as important covariates to consider in genetic studies of PD.

S35

local network structure) and a weighted path length (L, an index of global network integration). All results were compared with reference data from ensembles of random networks. Results: Multivariate testing using the ratio of C to L (C/L) in the six frequency bands as within-subject factor, group as between-subject factor and age as covariate showed a main effect of C/L as well as a significant interaction with group. Post-hoc analyses revealed increases in the ratio in all but the gamma frequency band in the whole group of PD patients relative to the controls. Results of the comparison of subgroups of PD patients, which differ with regard to disease duration, to controls will be presented. Conclusion: The present study demonstrates that PD is characterised by changes in the large-scale structure of resting-state brain networks. The observed increases in the clustering coefficient relative to the path length are compatible with a change of brain networks towards a more ordered network configuration. In this respect, PD is different from other brain disorders, where a more random structure of resting state brain networks has been found (Stam and Reijneveld, Nonlinear Biomed Phys 2007;1(1):3).

1.107 Comparing computer-assisted 3D reconstructions of the human substantia nigra with disector stereology 1.105 Stressful life events and Parkinson’s disease: A case-control study S. Sipetic-Grujicic1° , H. Vlajinac, J. Maksimovic, J. Marinkovic, E. Dzoljic, I. Ratkov, V. Kostic 1 Belgrade, Serbia and Montenegro Objective: In order to investigate possible relationship between stressful life events and Parkinson’s disease a case-control study was conducted. Method: The group of 110 consecutive newly diagnosed Parkinson’s disease cases was compared with the control group comprising 220 subjects. Cases and controls were matched by sex, age and place of residence. Results: According to conditional multivariate logistic regression analysis, Parkinson’s disease was significantly related to retirement (Odds ratio – OR = 18.73, 95% confidence interval – 95% CI: 1.99, 175.4), birth of child (OR = 66.22, 95% CI: 8.30, 526.3) and bombardment (OR = 5.66, 95% CI: 2.38, 13.48). Association with death of close friend was at the borderline of statistical significance (OR = 11.30, 95% CI: 0.94, 135.1). The average number of stressful life events was significantly greater in cases than controls (p < 0.001), and the risk increased with the number of stressful events (p < 0.001). Conclusion: The results of the present study support the hypothesis that stress can play a role in the development of Parkinson’s disease.

1.106 Are brain networks changed in Parkinson’s disease? A graph theoretical analysis of resting-state magneto-encephalographic functional connectivity D. Stoffers1° , J.L. Bosboom, J.B. Deijen, E.Ch. Wolters, C. Stam, H.W. Berendse 1 Amsterdam, Netherlands Objective: To examine changes in the large-scale structure of restingstate brain networks in patients with Parkinson’s disease (PD) using concepts from graph theory. Method: Whole-head 151-channel magnetoencephalography (MEG) recordings were obtained in an eyes-closed resting-state condition in 70 PD patients with varying disease duration and severity (including 18 earlystage, untreated patients) as well as in 21 controls. Correlations between all pair-wise combinations of MEG channels were determined with the synchronization likelihood (SL, a general measure of linear and nonlinear temporal correlations between time series). Subsequently, graph theoretical analysis was applied to matrices of functional connectivity of MEG channels in six major frequency domains. Connectivity networks were characterised by a weighted clustering coefficient (C, an index of

L. Tenenholz Grinberg1° , H. Heinsen Paulo, Brazil

1 S˜ ao

Objective: Previously we succeeded in a computer-assisted 3D reconstruction of the substantiae nigrae of 3 control cases and one case of Parkinson’s disease. The individual cases exhibited a tremendous variability in size and shape. Method: To further elucidate the reasons for this variability the cases were subjected to an unbiased stereological analysis by applying the disector on serial 400 to 440 mm thick gallocyanin-stained sections through the rostro-caudal extent of the substantia nigra of the same cases. Results: The volumes of the substantiae nigrae varied from 26 to 64.8 mm3 with the lowest volume in the right side of a 68-year-old female PD patient and. the highest volume in the right substantia nigra of a 49-year-old male control case. The latter substantia nigra exhibited the most complex structure in the 3D reconstruction. Likewise, nerve cell density varied considerably with the lowest one in the right substantia nigra of the 49-yearold control case (3219 neurons/mm3 ) followed the left substantia nigra of the PD case (3477 neurons/mm3 ). The highest density was encountered a 50-year-old control female (5607 neurons/mm3 ). The total neuron number varied from 253414 neurons (left substantia nigra of the 50 year-old-female control case) to 115502 (right substantia nigra of the 68-year-old female PD case). Conclusion: Similar to size and shape volume, neurondensity and neuron number of substantiae nigrae in our cases so far investigated exhibit an enormous variability. Obviously there is no simple correlation between size and shape on one side and volume, neurodensity and neuron number on the other side. In order to elucidate function and integrity of the substantia nigra in aging and neurodegenerative diseases a high number of substantiae nigrae should be subjected to a comprehensive hierarchical study including a combination of different methodological approaches.

1.108 Depression presenting before motor manifestation of Parkinson’s disease: Impact on motor and cognitive features N. Klepac1° , M. Relja Croatia

1 Zagreb,

Background: Depression occurs more often in Parkinson’s disease (PD) than in other chronic disorders. There are also evidences that in some patients depressive symptoms may precede motor manifestation. Objectives: To assess the impact of depression manifesting before motor symptoms of PD on clinical and cognitive features of PD.