Introduction: Parkinson's disease (PD) is a neurodegenerative disorder affecting a substantial proportion of the elderly Cypriot population. The objective of this study was to evaluate PD risk variants that have been identified previously in Genome Wide Association Studies (GWAS) and to find environmental factors that are predictors for PD onset in the Cypriot population.Methods: A case-control study was conducted with a total of 235 PD patients and 464 healthy controls of Greek-Cypriot ethnicity. Demographic and lifestyle characteristics, exposure to PD risk factors and clinical data were collected. Moreover, 13 previously GWAS-identified PD risk variants were genotyped. Univariate and multivariate regression analyses examined the association between a number of environmental and genetic factors and PD.Results: Multivariable regression analysis revealed that exposure to both pesticides and other toxic substances (P = 0.03), severe head injury accompanied with fainting (P = 0.001), nuts consumption (P = 0.004), red meat consumption (P = 0.02), and soft drinks consumption (P = 0.008) were increasing the risk for PD, whereas cumulative smoking (P = 0.02), and fish consumption (P = 0.02) were decreasing the risk for PD. Five out of the 13 tested SNPs (rs12185268, rs6599389, rs356220, rs13312, and rs17649553) were confirmed to be nominally significantly associated (P < 0.05) with PD risk in the Cypriot population.Conclusions: Collectively, this case-control study has shed some light on the nature of PD epidemiology in Cyprus, by demonstrating a number of genetic and environmental determinants of PD in the Cypriot population.

BackgroundDespite evidence supporting an involvement of mitochondrial dysfunction in the pathogenesis of some neurodegenerative disorders, there are inconsistent findings concerning mitochondrial haplogroups and their association to neurodegenerative disorders, including idiopathic Parkinson’s disease (PD).MethodsTo test this hypothesis for the Greek-Cypriot population, a cohort of 230 PD patients and 457 healthy matched controls were recruited. Mitochondrial haplogroup distributions for cases and controls were determined. Association tests were carried out between mitochondrial haplogroups and PD.ResultsMitochondrial haplogroup U was associated with a reduced PD risk in the Cypriot population. After pooling mitochondrial haplogroups together into haplogroup clusters and superclusters, association tests demonstrated a significantly protective effect of mitochondrial haplogroup cluster N (xR) and supercluster LMN for PD risk only in females. In addition, for female PD cases belonging to UKJT and R (xH, xUKJT) haplogroup, the odds of having a later age of onset of PD were 13 and 15 times respectively higher than the odds for female cases with an H haplogroup.ConclusionStatistically significant associations regarding PD risk and PD age of onset were mostly detected for females thus suggesting that gender is a risk modifier between mitochondrial haplogroups and PD status / PD age of onset. The biological mechanisms behind this gender specificity remain to be determined.

Abstract Background Crohn’s disease (CD) and ulcerative colitis (UC) are widely associated with smoking in epidemiological studies, whereas there are conflicting results for the association between CD and UC for both coffee and alcohol consumption. Herein, we aimed to investigate whether cigarette smoking and alcohol and coffee consumption are causally associated with either CD or UC. Methods We utilized 540 genome-wide significant single-nucleotide polymorphisms for 3 potentially addictive substances—nicotine, alcohol, and caffeine—to assess the association of smoking, coffee, and alcohol consumption with CD and UC (12,194 CD cases, 12,366 UC cases, and 25,042 controls of European ancestry), using Mendelian randomization analysis. Mendelian randomization estimates were used to evaluate the effect of the exposure factors on CD and UC risk. Sensitivity analysis was employed to test for any directional pleiotropy. Results We found evidence for a positive causal association between the age of smoking initiation and UC risk and between alcohol consumption and CD risk, which disappeared after sensitivity analysis for both associations (P &gt; 0.05). No evidence for a causal association between cigarettes per day, smoking initiation, smoking cessation, and coffee consumption variables and UC or CD was found. Conclusions We found no clear evidence that either genetically predicted smoking, coffee consumption, or alcohol consumption are causally associated with the risk for CD or UC, although our findings indicate a potential positive association between the age of smoking and UC and between alcohol consumption and CD.

Objectives: Recently a declining trend in dementia incidence rates has been reported in high-income countries. We investigated dementia incidence in a representative sample of the Greek population in the age group of 65 years and above. Methods: This research is part of the Hellenic Epidemiological Longitudinal Investigation of Aging and Diet (HELIAD). The incidence cohort consisted of 1072 participants who were reevaluated after a mean period of 3.09 years. Results: The incidence rate of dementia was 19.0 cases per 1000 person-years (age-standardized and sex-standardized incidence: 25.4/1000 person-years), of which 16.3 per 1000 person-years were attributable to Alzheimer disease. Each additional year of age increased dementia risk by 19.3% and each additional year of education decreased dementia risk by 12.1%. Apolipoprotein E (APOE)-ε4 homozygous participants were 18 times more likely to be diagnosed with dementia. A baseline diagnosis of mild cognitive decline (MCI) resulted in a risk for dementia increased by 3.7 times compared with the cognitively normal; in participants with MCI at baseline, APOE-ε4 carriage increased dementia risk by 4.5 times. Conclusions: The incidence rate of dementia in people 65 years and above in Greece is generally consistent with recently published rates in Europe and North America. Advancing age, baseline MCI, and APOE-ε4 homozygosity are risk factors, while higher educational attainment seems protective.