![Sample our Environment & Agriculture journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5934/TOC-Subject-Sample-2021-Environment-Agriculture.jpg"})
Abstract
The cardiovascular structure is temporally organized in both health and disease. The link between obesity and hypertension is elevated sympathetic nervous system activity and hormonal activity which present a clear rhythmicity, with the pineal, corticosteroid and leptin systems being those most implicated. Also, genetic mutations or deletions have implicated peripheral clock genes in the regulation of glucose homeostasis, lipid synthesis and adipogenesis, which are associated with obesity and type 2 diabetes mellitus. As hypertension and obesity are related, and the treatments of these disorders are well established but sometimes ineffective, this review focuses on chronobiological contributions to decrease the burden of hypertension and obesity in low- and middle-income groups of individuals. MEDLINE, Pubmed and SUMSearch sites (2001–2011) were used in the search strategy, together with the keywords: “antihypertensive drugs”; “arterial hypertension”; “circadian rhythms”; “obesity”; and “sleep quality”. Eighty-six articles were found and 50 articles from these were selected. A link between the circadian clock and hypertension has recently been described in animal models, using Clock-mutant mice that display metabolic syndrome. Experimental evidence clearly implicates circadian rhythms in the mechanisms that underlie the regulation of the blood pressure (BP) rhythm. Most clinical studies of BP focus on some pathological situation, such as hypertension, cardiovascular disease, sleep disorders, obesity, diabetes or pregnancy with blood biomarker alterations. However, epidemiological evidence for the role of circadian rhythms in hypertension has been lacking until recently. In Brazil, in an epidemiological, cross-sectional study, changed sleep quality and an earlier phase of mid-sleep were found in those using antihypertensive drugs. Moreover, some pharmacological studies support a circadian- and dose-dependent relationship in the use of antihypertensive drugs for the 24-h control of BP. In low- and middle-income areas, cost-effectiveness of any intervention is fundamental to the implementation of any kind of public-health policy. Therefore, improvements in diagnosis, effectiveness and implementing prevention measures to control the risk of disease are all necessary, and there is evidence that chronobiology has an important role to play. Consequently, it is important to provide guidelines to monitor BP to reduce cardiovascular risk that include chronobiological aspects of the problem.