The Modern Environment: The New Secondary Cause of Hypertension?

The most important risk factor for cardiovascular disease, the leading cause of death worldwide, is hypertension. Although most cases of hypertension are thought to be essential, the multifactorial associations of the environmental influence on blood pressure seem to play an important role and should be more closely investigated. This review attempts to focus on the recent literature that examines the environmental effects on arterial blood pressure and its management. Seasonal variability and the role of ambient temperature, either occupational or recreational noise pollution, as well as obesity due to environment-caused dietary habits, are recognized as important risk factors, affecting the onset as well as the regulation of hypertension. Furthermore, the effects of seasonal fluctuations in blood pressure, noise pollution, and obesity seem to share a similar pathogenesis, and as such to all further react together, leading to increased blood pressure. The activation of the autonomous nervous system plays a key role and causes an increase in stress hormones that generates oxidative stress on the vascular system and, thus, vasoconstriction. In this review, by focusing on the association of the environmental impact with arterial blood pressure, we come to the question of whether most cases of hypertension-if not all-should, indeed, be considered primary or secondary.

Association Between rs2200733 Polymorphism on Chromosome 4q25 and Atrial Fibrillation in a Greek Population.

INTRODUCTION: Atrial fibrillation (AF) is a common arrhythmia with evidence of genetic susceptibility. The rs2200733 single-nucleotide polymorphism (SNP) in a non-coding region on chromosome 4q25 has been associated with AF. The purpose of this case-control study was to examine the possible association of the rs2200733 polymorphism with AF in the Greek population. METHODS: A total of 295 individuals, 167 AF patients and 128 controls, were genotyped for the presence of the rs2200733 polymorphism using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLPs) method. RESULTS: The T/T genotype and the T allele were detected more frequently in patients with AF compared to controls (13.2% vs. 2.3%, p=0.001, and 29.6% vs. 17.9%, p=0.001), suggesting that the rs2200733 polymorphism increases susceptibility to AF in the Greek population. In a multivariate stepwise analysis that included many conventional precipitating factors for AF, T/T genotype and left atrium (LA) diameter were the only independent predictors of AF (OR 1.74, 95% CI: 1.40-2.98, p=0.005, and OR 2.88, 95% CI: 1.835.62, p<0.001, respectively). A trend of association was observed between the T/T genotype and lone AF (p=0.08). CONCLUSIONS: Our results suggest that SNP rs2200733 confers a significant risk of AF in the Greek population, providing further support to the previously reported association between AF and rs2200733 polymorphism on chromosome 4q25.